hooks.c 167.6 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5
/*
 *  NSA Security-Enhanced Linux (SELinux) security module
 *
 *  This file contains the SELinux hook function implementations.
 *
6
 *  Authors:  Stephen Smalley, <sds@tycho.nsa.gov>
7 8 9
 *	      Chris Vance, <cvance@nai.com>
 *	      Wayne Salamon, <wsalamon@nai.com>
 *	      James Morris <jmorris@redhat.com>
L
Linus Torvalds 已提交
10 11
 *
 *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 13
 *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
 *					   Eric Paris <eparis@redhat.com>
L
Linus Torvalds 已提交
14
 *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15
 *			    <dgoeddel@trustedcs.com>
16
 *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17
 *	Paul Moore <paul@paul-moore.com>
18
 *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19
 *		       Yuichi Nakamura <ynakam@hitachisoft.jp>
20
 *  Copyright (C) 2016 Mellanox Technologies
L
Linus Torvalds 已提交
21 22 23
 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License version 2,
24
 *	as published by the Free Software Foundation.
L
Linus Torvalds 已提交
25 26 27
 */

#include <linux/init.h>
28
#include <linux/kd.h>
L
Linus Torvalds 已提交
29
#include <linux/kernel.h>
30
#include <linux/tracehook.h>
L
Linus Torvalds 已提交
31
#include <linux/errno.h>
32
#include <linux/sched/signal.h>
33
#include <linux/sched/task.h>
C
Casey Schaufler 已提交
34
#include <linux/lsm_hooks.h>
L
Linus Torvalds 已提交
35 36 37 38 39 40 41
#include <linux/xattr.h>
#include <linux/capability.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
42
#include <linux/proc_fs.h>
L
Linus Torvalds 已提交
43 44 45
#include <linux/swap.h>
#include <linux/spinlock.h>
#include <linux/syscalls.h>
46
#include <linux/dcache.h>
L
Linus Torvalds 已提交
47
#include <linux/file.h>
A
Al Viro 已提交
48
#include <linux/fdtable.h>
L
Linus Torvalds 已提交
49 50 51 52 53 54
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/tty.h>
#include <net/icmp.h>
55
#include <net/ip.h>		/* for local_port_range[] */
L
Linus Torvalds 已提交
56
#include <net/tcp.h>		/* struct or_callable used in sock_rcv_skb */
57
#include <net/inet_connection_sock.h>
58
#include <net/net_namespace.h>
59
#include <net/netlabel.h>
60
#include <linux/uaccess.h>
L
Linus Torvalds 已提交
61
#include <asm/ioctls.h>
A
Arun Sharma 已提交
62
#include <linux/atomic.h>
L
Linus Torvalds 已提交
63 64 65
#include <linux/bitops.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>	/* for network interface checks */
66
#include <net/netlink.h>
L
Linus Torvalds 已提交
67 68
#include <linux/tcp.h>
#include <linux/udp.h>
J
James Morris 已提交
69
#include <linux/dccp.h>
L
Linus Torvalds 已提交
70 71 72 73 74 75 76 77 78
#include <linux/quota.h>
#include <linux/un.h>		/* for Unix socket types */
#include <net/af_unix.h>	/* for Unix socket types */
#include <linux/parser.h>
#include <linux/nfs_mount.h>
#include <net/ipv6.h>
#include <linux/hugetlb.h>
#include <linux/personality.h>
#include <linux/audit.h>
79
#include <linux/string.h>
C
Catherine Zhang 已提交
80
#include <linux/selinux.h>
81
#include <linux/mutex.h>
82
#include <linux/posix-timers.h>
83
#include <linux/syslog.h>
84
#include <linux/user_namespace.h>
85
#include <linux/export.h>
A
Al Viro 已提交
86 87
#include <linux/msg.h>
#include <linux/shm.h>
L
Linus Torvalds 已提交
88 89 90 91

#include "avc.h"
#include "objsec.h"
#include "netif.h"
92
#include "netnode.h"
P
Paul Moore 已提交
93
#include "netport.h"
94
#include "ibpkey.h"
95
#include "xfrm.h"
96
#include "netlabel.h"
97
#include "audit.h"
98
#include "avc_ss.h"
L
Linus Torvalds 已提交
99

100
/* SECMARK reference count */
101
static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
102

L
Linus Torvalds 已提交
103
#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
104
int selinux_enforcing;
L
Linus Torvalds 已提交
105 106 107

static int __init enforcing_setup(char *str)
{
108
	unsigned long enforcing;
109
	if (!kstrtoul(str, 0, &enforcing))
110
		selinux_enforcing = enforcing ? 1 : 0;
L
Linus Torvalds 已提交
111 112 113 114 115 116 117 118 119 120
	return 1;
}
__setup("enforcing=", enforcing_setup);
#endif

#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;

static int __init selinux_enabled_setup(char *str)
{
121
	unsigned long enabled;
122
	if (!kstrtoul(str, 0, &enabled))
123
		selinux_enabled = enabled ? 1 : 0;
L
Linus Torvalds 已提交
124 125 126
	return 1;
}
__setup("selinux=", selinux_enabled_setup);
127 128
#else
int selinux_enabled = 1;
L
Linus Torvalds 已提交
129 130
#endif

131
static struct kmem_cache *sel_inode_cache;
132
static struct kmem_cache *file_security_cache;
133

134 135 136 137 138 139 140
/**
 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 *
 * Description:
 * This function checks the SECMARK reference counter to see if any SECMARK
 * targets are currently configured, if the reference counter is greater than
 * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
141 142
 * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 * policy capability is enabled, SECMARK is always considered enabled.
143 144 145 146
 *
 */
static int selinux_secmark_enabled(void)
{
147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162
	return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
}

/**
 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 *
 * Description:
 * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 * (1) if any are enabled or false (0) if neither are enabled.  If the
 * always_check_network policy capability is enabled, peer labeling
 * is always considered enabled.
 *
 */
static int selinux_peerlbl_enabled(void)
{
	return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
163 164
}

165 166 167 168 169 170 171 172 173 174 175
static int selinux_netcache_avc_callback(u32 event)
{
	if (event == AVC_CALLBACK_RESET) {
		sel_netif_flush();
		sel_netnode_flush();
		sel_netport_flush();
		synchronize_net();
	}
	return 0;
}

176 177
static int selinux_lsm_notifier_avc_callback(u32 event)
{
178 179
	if (event == AVC_CALLBACK_RESET) {
		sel_ib_pkey_flush();
180
		call_lsm_notifier(LSM_POLICY_CHANGE, NULL);
181
	}
182 183 184 185

	return 0;
}

D
David Howells 已提交
186 187 188 189
/*
 * initialise the security for the init task
 */
static void cred_init_security(void)
L
Linus Torvalds 已提交
190
{
191
	struct cred *cred = (struct cred *) current->real_cred;
L
Linus Torvalds 已提交
192 193
	struct task_security_struct *tsec;

J
James Morris 已提交
194
	tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
195
	if (!tsec)
D
David Howells 已提交
196
		panic("SELinux:  Failed to initialize initial task.\n");
L
Linus Torvalds 已提交
197

D
David Howells 已提交
198
	tsec->osid = tsec->sid = SECINITSID_KERNEL;
199
	cred->security = tsec;
L
Linus Torvalds 已提交
200 201
}

202 203 204 205 206 207 208 209 210 211 212
/*
 * get the security ID of a set of credentials
 */
static inline u32 cred_sid(const struct cred *cred)
{
	const struct task_security_struct *tsec;

	tsec = cred->security;
	return tsec->sid;
}

213
/*
214
 * get the objective security ID of a task
215 216 217 218 219 220
 */
static inline u32 task_sid(const struct task_struct *task)
{
	u32 sid;

	rcu_read_lock();
221
	sid = cred_sid(__task_cred(task));
222 223 224 225
	rcu_read_unlock();
	return sid;
}

226 227
/* Allocate and free functions for each kind of security blob. */

L
Linus Torvalds 已提交
228 229 230
static int inode_alloc_security(struct inode *inode)
{
	struct inode_security_struct *isec;
231
	u32 sid = current_sid();
L
Linus Torvalds 已提交
232

233
	isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
L
Linus Torvalds 已提交
234 235 236
	if (!isec)
		return -ENOMEM;

237
	spin_lock_init(&isec->lock);
L
Linus Torvalds 已提交
238 239 240 241
	INIT_LIST_HEAD(&isec->list);
	isec->inode = inode;
	isec->sid = SECINITSID_UNLABELED;
	isec->sclass = SECCLASS_FILE;
242
	isec->task_sid = sid;
A
Andreas Gruenbacher 已提交
243
	isec->initialized = LABEL_INVALID;
L
Linus Torvalds 已提交
244 245 246 247 248
	inode->i_security = isec;

	return 0;
}

249 250 251 252 253
static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);

/*
 * Try reloading inode security labels that have been marked as invalid.  The
 * @may_sleep parameter indicates when sleeping and thus reloading labels is
A
Andreas Gruenbacher 已提交
254
 * allowed; when set to false, returns -ECHILD when the label is
255 256 257 258 259 260 261 262 263 264 265
 * invalid.  The @opt_dentry parameter should be set to a dentry of the inode;
 * when no dentry is available, set it to NULL instead.
 */
static int __inode_security_revalidate(struct inode *inode,
				       struct dentry *opt_dentry,
				       bool may_sleep)
{
	struct inode_security_struct *isec = inode->i_security;

	might_sleep_if(may_sleep);

266
	if (ss_initialized && isec->initialized != LABEL_INITIALIZED) {
267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294
		if (!may_sleep)
			return -ECHILD;

		/*
		 * Try reloading the inode security label.  This will fail if
		 * @opt_dentry is NULL and no dentry for this inode can be
		 * found; in that case, continue using the old label.
		 */
		inode_doinit_with_dentry(inode, opt_dentry);
	}
	return 0;
}

static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
{
	return inode->i_security;
}

static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
{
	int error;

	error = __inode_security_revalidate(inode, NULL, !rcu);
	if (error)
		return ERR_PTR(error);
	return inode->i_security;
}

295 296 297 298 299
/*
 * Get the security label of an inode.
 */
static struct inode_security_struct *inode_security(struct inode *inode)
{
300
	__inode_security_revalidate(inode, NULL, true);
301 302 303
	return inode->i_security;
}

304 305 306 307 308 309 310
static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
{
	struct inode *inode = d_backing_inode(dentry);

	return inode->i_security;
}

311 312 313 314 315 316 317
/*
 * Get the security label of a dentry's backing inode.
 */
static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
{
	struct inode *inode = d_backing_inode(dentry);

318
	__inode_security_revalidate(inode, dentry, true);
319 320 321
	return inode->i_security;
}

322 323 324 325 326 327 328 329
static void inode_free_rcu(struct rcu_head *head)
{
	struct inode_security_struct *isec;

	isec = container_of(head, struct inode_security_struct, rcu);
	kmem_cache_free(sel_inode_cache, isec);
}

L
Linus Torvalds 已提交
330 331 332 333 334
static void inode_free_security(struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
	struct superblock_security_struct *sbsec = inode->i_sb->s_security;

335 336 337 338 339 340 341 342 343 344 345 346
	/*
	 * As not all inode security structures are in a list, we check for
	 * empty list outside of the lock to make sure that we won't waste
	 * time taking a lock doing nothing.
	 *
	 * The list_del_init() function can be safely called more than once.
	 * It should not be possible for this function to be called with
	 * concurrent list_add(), but for better safety against future changes
	 * in the code, we use list_empty_careful() here.
	 */
	if (!list_empty_careful(&isec->list)) {
		spin_lock(&sbsec->isec_lock);
L
Linus Torvalds 已提交
347
		list_del_init(&isec->list);
348 349
		spin_unlock(&sbsec->isec_lock);
	}
L
Linus Torvalds 已提交
350

351 352 353 354 355 356 357 358 359 360
	/*
	 * The inode may still be referenced in a path walk and
	 * a call to selinux_inode_permission() can be made
	 * after inode_free_security() is called. Ideally, the VFS
	 * wouldn't do this, but fixing that is a much harder
	 * job. For now, simply free the i_security via RCU, and
	 * leave the current inode->i_security pointer intact.
	 * The inode will be freed after the RCU grace period too.
	 */
	call_rcu(&isec->rcu, inode_free_rcu);
L
Linus Torvalds 已提交
361 362 363 364 365
}

static int file_alloc_security(struct file *file)
{
	struct file_security_struct *fsec;
366
	u32 sid = current_sid();
L
Linus Torvalds 已提交
367

368
	fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
L
Linus Torvalds 已提交
369 370 371
	if (!fsec)
		return -ENOMEM;

372 373
	fsec->sid = sid;
	fsec->fown_sid = sid;
L
Linus Torvalds 已提交
374 375 376 377 378 379 380 381 382
	file->f_security = fsec;

	return 0;
}

static void file_free_security(struct file *file)
{
	struct file_security_struct *fsec = file->f_security;
	file->f_security = NULL;
383
	kmem_cache_free(file_security_cache, fsec);
L
Linus Torvalds 已提交
384 385 386 387 388 389
}

static int superblock_alloc_security(struct super_block *sb)
{
	struct superblock_security_struct *sbsec;

J
James Morris 已提交
390
	sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
391 392 393
	if (!sbsec)
		return -ENOMEM;

394
	mutex_init(&sbsec->lock);
L
Linus Torvalds 已提交
395 396 397 398 399
	INIT_LIST_HEAD(&sbsec->isec_head);
	spin_lock_init(&sbsec->isec_lock);
	sbsec->sb = sb;
	sbsec->sid = SECINITSID_UNLABELED;
	sbsec->def_sid = SECINITSID_FILE;
400
	sbsec->mntpoint_sid = SECINITSID_UNLABELED;
L
Linus Torvalds 已提交
401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418
	sb->s_security = sbsec;

	return 0;
}

static void superblock_free_security(struct super_block *sb)
{
	struct superblock_security_struct *sbsec = sb->s_security;
	sb->s_security = NULL;
	kfree(sbsec);
}

static inline int inode_doinit(struct inode *inode)
{
	return inode_doinit_with_dentry(inode, NULL);
}

enum {
419
	Opt_error = -1,
L
Linus Torvalds 已提交
420 421
	Opt_context = 1,
	Opt_fscontext = 2,
422 423
	Opt_defcontext = 3,
	Opt_rootcontext = 4,
424
	Opt_labelsupport = 5,
425
	Opt_nextmntopt = 6,
L
Linus Torvalds 已提交
426 427
};

428 429
#define NUM_SEL_MNT_OPTS	(Opt_nextmntopt - 1)

430
static const match_table_t tokens = {
431 432 433 434
	{Opt_context, CONTEXT_STR "%s"},
	{Opt_fscontext, FSCONTEXT_STR "%s"},
	{Opt_defcontext, DEFCONTEXT_STR "%s"},
	{Opt_rootcontext, ROOTCONTEXT_STR "%s"},
435
	{Opt_labelsupport, LABELSUPP_STR},
436
	{Opt_error, NULL},
L
Linus Torvalds 已提交
437 438 439 440
};

#define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"

441 442
static int may_context_mount_sb_relabel(u32 sid,
			struct superblock_security_struct *sbsec,
443
			const struct cred *cred)
444
{
445
	const struct task_security_struct *tsec = cred->security;
446 447 448 449 450 451 452 453 454 455 456 457
	int rc;

	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELFROM, NULL);
	if (rc)
		return rc;

	rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELTO, NULL);
	return rc;
}

458 459
static int may_context_mount_inode_relabel(u32 sid,
			struct superblock_security_struct *sbsec,
460
			const struct cred *cred)
461
{
462
	const struct task_security_struct *tsec = cred->security;
463 464 465 466 467 468 469 470 471 472 473
	int rc;
	rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__RELABELFROM, NULL);
	if (rc)
		return rc;

	rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
			  FILESYSTEM__ASSOCIATE, NULL);
	return rc;
}

474 475 476 477
static int selinux_is_sblabel_mnt(struct super_block *sb)
{
	struct superblock_security_struct *sbsec = sb->s_security;

478 479 480
	return sbsec->behavior == SECURITY_FS_USE_XATTR ||
		sbsec->behavior == SECURITY_FS_USE_TRANS ||
		sbsec->behavior == SECURITY_FS_USE_TASK ||
481
		sbsec->behavior == SECURITY_FS_USE_NATIVE ||
482 483 484 485
		/* Special handling. Genfs but also in-core setxattr handler */
		!strcmp(sb->s_type->name, "sysfs") ||
		!strcmp(sb->s_type->name, "pstore") ||
		!strcmp(sb->s_type->name, "debugfs") ||
486
		!strcmp(sb->s_type->name, "tracefs") ||
487 488 489 490
		!strcmp(sb->s_type->name, "rootfs") ||
		(selinux_policycap_cgroupseclabel &&
		 (!strcmp(sb->s_type->name, "cgroup") ||
		  !strcmp(sb->s_type->name, "cgroup2")));
491 492
}

493
static int sb_finish_set_opts(struct super_block *sb)
L
Linus Torvalds 已提交
494 495
{
	struct superblock_security_struct *sbsec = sb->s_security;
496
	struct dentry *root = sb->s_root;
497
	struct inode *root_inode = d_backing_inode(root);
498
	int rc = 0;
L
Linus Torvalds 已提交
499

500 501 502 503 504 505
	if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
		/* Make sure that the xattr handler exists and that no
		   error other than -ENODATA is returned by getxattr on
		   the root directory.  -ENODATA is ok, as this may be
		   the first boot of the SELinux kernel before we have
		   assigned xattr values to the filesystem. */
506
		if (!(root_inode->i_opflags & IOP_XATTR)) {
507 508
			printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
			       "xattr support\n", sb->s_id, sb->s_type->name);
509 510 511
			rc = -EOPNOTSUPP;
			goto out;
		}
512 513

		rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
514 515 516
		if (rc < 0 && rc != -ENODATA) {
			if (rc == -EOPNOTSUPP)
				printk(KERN_WARNING "SELinux: (dev %s, type "
517 518
				       "%s) has no security xattr handler\n",
				       sb->s_id, sb->s_type->name);
519 520
			else
				printk(KERN_WARNING "SELinux: (dev %s, type "
521 522
				       "%s) getxattr errno %d\n", sb->s_id,
				       sb->s_type->name, -rc);
523 524 525
			goto out;
		}
	}
L
Linus Torvalds 已提交
526

527
	sbsec->flags |= SE_SBINITIALIZED;
528 529 530 531 532 533

	/*
	 * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
	 * leave the flag untouched because sb_clone_mnt_opts might be handing
	 * us a superblock that needs the flag to be cleared.
	 */
534
	if (selinux_is_sblabel_mnt(sb))
535
		sbsec->flags |= SBLABEL_MNT;
536 537
	else
		sbsec->flags &= ~SBLABEL_MNT;
538

539 540
	/* Initialize the root inode. */
	rc = inode_doinit_with_dentry(root_inode, root);
L
Linus Torvalds 已提交
541

542 543 544 545 546 547 548 549 550 551 552
	/* Initialize any other inodes associated with the superblock, e.g.
	   inodes created prior to initial policy load or inodes created
	   during get_sb by a pseudo filesystem that directly
	   populates itself. */
	spin_lock(&sbsec->isec_lock);
next_inode:
	if (!list_empty(&sbsec->isec_head)) {
		struct inode_security_struct *isec =
				list_entry(sbsec->isec_head.next,
					   struct inode_security_struct, list);
		struct inode *inode = isec->inode;
553
		list_del_init(&isec->list);
554 555 556 557 558 559 560 561 562 563 564 565 566 567
		spin_unlock(&sbsec->isec_lock);
		inode = igrab(inode);
		if (inode) {
			if (!IS_PRIVATE(inode))
				inode_doinit(inode);
			iput(inode);
		}
		spin_lock(&sbsec->isec_lock);
		goto next_inode;
	}
	spin_unlock(&sbsec->isec_lock);
out:
	return rc;
}
L
Linus Torvalds 已提交
568

569 570 571 572 573 574
/*
 * This function should allow an FS to ask what it's mount security
 * options were so it can use those later for submounts, displaying
 * mount options, or whatever.
 */
static int selinux_get_mnt_opts(const struct super_block *sb,
575
				struct security_mnt_opts *opts)
576 577 578 579 580 581
{
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
	char *context = NULL;
	u32 len;
	char tmp;
L
Linus Torvalds 已提交
582

583
	security_init_mnt_opts(opts);
L
Linus Torvalds 已提交
584

585
	if (!(sbsec->flags & SE_SBINITIALIZED))
586
		return -EINVAL;
L
Linus Torvalds 已提交
587

588 589
	if (!ss_initialized)
		return -EINVAL;
L
Linus Torvalds 已提交
590

591 592 593
	/* make sure we always check enough bits to cover the mask */
	BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));

594
	tmp = sbsec->flags & SE_MNTMASK;
595
	/* count the number of mount options for this sb */
596
	for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
597
		if (tmp & 0x01)
598
			opts->num_mnt_opts++;
599 600
		tmp >>= 1;
	}
601
	/* Check if the Label support flag is set */
602
	if (sbsec->flags & SBLABEL_MNT)
603
		opts->num_mnt_opts++;
L
Linus Torvalds 已提交
604

605 606
	opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
	if (!opts->mnt_opts) {
607 608 609
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
610

611 612
	opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
	if (!opts->mnt_opts_flags) {
613 614 615
		rc = -ENOMEM;
		goto out_free;
	}
L
Linus Torvalds 已提交
616

617 618 619 620 621
	i = 0;
	if (sbsec->flags & FSCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->sid, &context, &len);
		if (rc)
			goto out_free;
622 623
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
624 625 626 627 628
	}
	if (sbsec->flags & CONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
		if (rc)
			goto out_free;
629 630
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = CONTEXT_MNT;
631 632 633 634 635
	}
	if (sbsec->flags & DEFCONTEXT_MNT) {
		rc = security_sid_to_context(sbsec->def_sid, &context, &len);
		if (rc)
			goto out_free;
636 637
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
638 639
	}
	if (sbsec->flags & ROOTCONTEXT_MNT) {
640 641
		struct dentry *root = sbsec->sb->s_root;
		struct inode_security_struct *isec = backing_inode_security(root);
642

643 644 645
		rc = security_sid_to_context(isec->sid, &context, &len);
		if (rc)
			goto out_free;
646 647
		opts->mnt_opts[i] = context;
		opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
648
	}
649
	if (sbsec->flags & SBLABEL_MNT) {
650
		opts->mnt_opts[i] = NULL;
651
		opts->mnt_opts_flags[i++] = SBLABEL_MNT;
652
	}
L
Linus Torvalds 已提交
653

654
	BUG_ON(i != opts->num_mnt_opts);
L
Linus Torvalds 已提交
655

656 657 658
	return 0;

out_free:
659
	security_free_mnt_opts(opts);
660 661
	return rc;
}
L
Linus Torvalds 已提交
662

663 664 665
static int bad_option(struct superblock_security_struct *sbsec, char flag,
		      u32 old_sid, u32 new_sid)
{
666 667
	char mnt_flags = sbsec->flags & SE_MNTMASK;

668
	/* check if the old mount command had the same options */
669
	if (sbsec->flags & SE_SBINITIALIZED)
670 671 672 673 674 675 676
		if (!(sbsec->flags & flag) ||
		    (old_sid != new_sid))
			return 1;

	/* check if we were passed the same options twice,
	 * aka someone passed context=a,context=b
	 */
677 678
	if (!(sbsec->flags & SE_SBINITIALIZED))
		if (mnt_flags & flag)
679 680 681
			return 1;
	return 0;
}
682

683 684 685 686
/*
 * Allow filesystems with binary mount data to explicitly set mount point
 * labeling information.
 */
687
static int selinux_set_mnt_opts(struct super_block *sb,
688 689 690
				struct security_mnt_opts *opts,
				unsigned long kern_flags,
				unsigned long *set_kern_flags)
691
{
692
	const struct cred *cred = current_cred();
693 694
	int rc = 0, i;
	struct superblock_security_struct *sbsec = sb->s_security;
695
	const char *name = sb->s_type->name;
696
	struct dentry *root = sbsec->sb->s_root;
697
	struct inode_security_struct *root_isec;
698 699
	u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
	u32 defcontext_sid = 0;
700 701 702
	char **mount_options = opts->mnt_opts;
	int *flags = opts->mnt_opts_flags;
	int num_opts = opts->num_mnt_opts;
703 704 705 706 707 708 709 710 711 712 713

	mutex_lock(&sbsec->lock);

	if (!ss_initialized) {
		if (!num_opts) {
			/* Defer initialization until selinux_complete_init,
			   after the initial policy is loaded and the security
			   server is ready to handle calls. */
			goto out;
		}
		rc = -EINVAL;
E
Eric Paris 已提交
714 715
		printk(KERN_WARNING "SELinux: Unable to set superblock options "
			"before the security server is initialized\n");
L
Linus Torvalds 已提交
716
		goto out;
717
	}
718 719 720 721 722 723
	if (kern_flags && !set_kern_flags) {
		/* Specifying internal flags without providing a place to
		 * place the results is not allowed */
		rc = -EINVAL;
		goto out;
	}
L
Linus Torvalds 已提交
724

725 726 727 728 729 730 731 732 733 734 735
	/*
	 * Binary mount data FS will come through this function twice.  Once
	 * from an explicit call and once from the generic calls from the vfs.
	 * Since the generic VFS calls will not contain any security mount data
	 * we need to skip the double mount verification.
	 *
	 * This does open a hole in which we will not notice if the first
	 * mount using this sb set explict options and a second mount using
	 * this sb does not set any security options.  (The first options
	 * will be used for both mounts)
	 */
736
	if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
737
	    && (num_opts == 0))
738
		goto out;
739

740 741
	root_isec = backing_inode_security_novalidate(root);

742 743 744 745 746 747 748
	/*
	 * parse the mount options, check if they are valid sids.
	 * also check if someone is trying to mount the same sb more
	 * than once with different security options.
	 */
	for (i = 0; i < num_opts; i++) {
		u32 sid;
749

750
		if (flags[i] == SBLABEL_MNT)
751
			continue;
752
		rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
L
Linus Torvalds 已提交
753
		if (rc) {
754
			printk(KERN_WARNING "SELinux: security_context_str_to_sid"
755 756
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, name, rc);
757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800
			goto out;
		}
		switch (flags[i]) {
		case FSCONTEXT_MNT:
			fscontext_sid = sid;

			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
					fscontext_sid))
				goto out_double_mount;

			sbsec->flags |= FSCONTEXT_MNT;
			break;
		case CONTEXT_MNT:
			context_sid = sid;

			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
					context_sid))
				goto out_double_mount;

			sbsec->flags |= CONTEXT_MNT;
			break;
		case ROOTCONTEXT_MNT:
			rootcontext_sid = sid;

			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
					rootcontext_sid))
				goto out_double_mount;

			sbsec->flags |= ROOTCONTEXT_MNT;

			break;
		case DEFCONTEXT_MNT:
			defcontext_sid = sid;

			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
					defcontext_sid))
				goto out_double_mount;

			sbsec->flags |= DEFCONTEXT_MNT;

			break;
		default:
			rc = -EINVAL;
			goto out;
L
Linus Torvalds 已提交
801
		}
802 803
	}

804
	if (sbsec->flags & SE_SBINITIALIZED) {
805
		/* previously mounted with options, but not on this attempt? */
806
		if ((sbsec->flags & SE_MNTMASK) && !num_opts)
807 808 809 810 811
			goto out_double_mount;
		rc = 0;
		goto out;
	}

812
	if (strcmp(sb->s_type->name, "proc") == 0)
813 814
		sbsec->flags |= SE_SBPROC | SE_SBGENFS;

815
	if (!strcmp(sb->s_type->name, "debugfs") ||
816
	    !strcmp(sb->s_type->name, "tracefs") ||
817
	    !strcmp(sb->s_type->name, "sysfs") ||
818 819 820
	    !strcmp(sb->s_type->name, "pstore") ||
	    !strcmp(sb->s_type->name, "cgroup") ||
	    !strcmp(sb->s_type->name, "cgroup2"))
821
		sbsec->flags |= SE_SBGENFS;
822

823 824 825 826 827
	if (!sbsec->behavior) {
		/*
		 * Determine the labeling behavior to use for this
		 * filesystem type.
		 */
828
		rc = security_fs_use(sb);
829 830 831 832 833 834
		if (rc) {
			printk(KERN_WARNING
				"%s: security_fs_use(%s) returned %d\n",
					__func__, sb->s_type->name, rc);
			goto out;
		}
835
	}
836 837

	/*
838 839 840
	 * If this is a user namespace mount and the filesystem type is not
	 * explicitly whitelisted, then no contexts are allowed on the command
	 * line and security labels must be ignored.
841
	 */
842 843 844 845
	if (sb->s_user_ns != &init_user_ns &&
	    strcmp(sb->s_type->name, "tmpfs") &&
	    strcmp(sb->s_type->name, "ramfs") &&
	    strcmp(sb->s_type->name, "devpts")) {
846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861
		if (context_sid || fscontext_sid || rootcontext_sid ||
		    defcontext_sid) {
			rc = -EACCES;
			goto out;
		}
		if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
			sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
			rc = security_transition_sid(current_sid(), current_sid(),
						     SECCLASS_FILE, NULL,
						     &sbsec->mntpoint_sid);
			if (rc)
				goto out;
		}
		goto out_set_opts;
	}

862 863
	/* sets the context of the superblock for the fs being mounted. */
	if (fscontext_sid) {
864
		rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
L
Linus Torvalds 已提交
865
		if (rc)
866
			goto out;
L
Linus Torvalds 已提交
867

868
		sbsec->sid = fscontext_sid;
869 870 871 872 873 874 875
	}

	/*
	 * Switch to using mount point labeling behavior.
	 * sets the label used on all file below the mountpoint, and will set
	 * the superblock context if not already set.
	 */
876 877 878 879 880
	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
		sbsec->behavior = SECURITY_FS_USE_NATIVE;
		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
	}

881 882
	if (context_sid) {
		if (!fscontext_sid) {
883 884
			rc = may_context_mount_sb_relabel(context_sid, sbsec,
							  cred);
885
			if (rc)
886 887
				goto out;
			sbsec->sid = context_sid;
888
		} else {
889 890
			rc = may_context_mount_inode_relabel(context_sid, sbsec,
							     cred);
891
			if (rc)
892
				goto out;
893
		}
894 895
		if (!rootcontext_sid)
			rootcontext_sid = context_sid;
L
Linus Torvalds 已提交
896

897
		sbsec->mntpoint_sid = context_sid;
898
		sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
L
Linus Torvalds 已提交
899 900
	}

901
	if (rootcontext_sid) {
902 903
		rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
						     cred);
904
		if (rc)
905
			goto out;
906

907
		root_isec->sid = rootcontext_sid;
908
		root_isec->initialized = LABEL_INITIALIZED;
909 910
	}

911
	if (defcontext_sid) {
912 913
		if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
			sbsec->behavior != SECURITY_FS_USE_NATIVE) {
914 915 916 917
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux: defcontext option is "
			       "invalid for this filesystem type\n");
			goto out;
L
Linus Torvalds 已提交
918 919
		}

920 921
		if (defcontext_sid != sbsec->def_sid) {
			rc = may_context_mount_inode_relabel(defcontext_sid,
922
							     sbsec, cred);
923 924 925
			if (rc)
				goto out;
		}
L
Linus Torvalds 已提交
926

927
		sbsec->def_sid = defcontext_sid;
L
Linus Torvalds 已提交
928 929
	}

930
out_set_opts:
931
	rc = sb_finish_set_opts(sb);
L
Linus Torvalds 已提交
932
out:
933
	mutex_unlock(&sbsec->lock);
L
Linus Torvalds 已提交
934
	return rc;
935 936 937
out_double_mount:
	rc = -EINVAL;
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
938
	       "security settings for (dev %s, type %s)\n", sb->s_id, name);
939
	goto out;
L
Linus Torvalds 已提交
940 941
}

942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958
static int selinux_cmp_sb_context(const struct super_block *oldsb,
				    const struct super_block *newsb)
{
	struct superblock_security_struct *old = oldsb->s_security;
	struct superblock_security_struct *new = newsb->s_security;
	char oldflags = old->flags & SE_MNTMASK;
	char newflags = new->flags & SE_MNTMASK;

	if (oldflags != newflags)
		goto mismatch;
	if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
		goto mismatch;
	if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
		goto mismatch;
	if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
		goto mismatch;
	if (oldflags & ROOTCONTEXT_MNT) {
959 960
		struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
		struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
961 962 963 964 965 966 967 968 969 970 971 972
		if (oldroot->sid != newroot->sid)
			goto mismatch;
	}
	return 0;
mismatch:
	printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
			    "different security settings for (dev %s, "
			    "type %s)\n", newsb->s_id, newsb->s_type->name);
	return -EBUSY;
}

static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
973 974 975
					struct super_block *newsb,
					unsigned long kern_flags,
					unsigned long *set_kern_flags)
L
Linus Torvalds 已提交
976
{
977
	int rc = 0;
978 979
	const struct superblock_security_struct *oldsbsec = oldsb->s_security;
	struct superblock_security_struct *newsbsec = newsb->s_security;
L
Linus Torvalds 已提交
980

981 982 983
	int set_fscontext =	(oldsbsec->flags & FSCONTEXT_MNT);
	int set_context =	(oldsbsec->flags & CONTEXT_MNT);
	int set_rootcontext =	(oldsbsec->flags & ROOTCONTEXT_MNT);
L
Linus Torvalds 已提交
984

985 986
	/*
	 * if the parent was able to be mounted it clearly had no special lsm
987
	 * mount options.  thus we can safely deal with this superblock later
988
	 */
989
	if (!ss_initialized)
990
		return 0;
991

992 993 994 995 996 997 998
	/*
	 * Specifying internal flags without providing a place to
	 * place the results is not allowed.
	 */
	if (kern_flags && !set_kern_flags)
		return -EINVAL;

999
	/* how can we clone if the old one wasn't set up?? */
1000
	BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
1001

1002
	/* if fs is reusing a sb, make sure that the contexts match */
1003
	if (newsbsec->flags & SE_SBINITIALIZED)
1004
		return selinux_cmp_sb_context(oldsb, newsb);
1005

1006 1007 1008 1009 1010 1011 1012 1013
	mutex_lock(&newsbsec->lock);

	newsbsec->flags = oldsbsec->flags;

	newsbsec->sid = oldsbsec->sid;
	newsbsec->def_sid = oldsbsec->def_sid;
	newsbsec->behavior = oldsbsec->behavior;

1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025
	if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
		!(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
		rc = security_fs_use(newsb);
		if (rc)
			goto out;
	}

	if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
		newsbsec->behavior = SECURITY_FS_USE_NATIVE;
		*set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
	}

1026 1027 1028 1029 1030 1031
	if (set_context) {
		u32 sid = oldsbsec->mntpoint_sid;

		if (!set_fscontext)
			newsbsec->sid = sid;
		if (!set_rootcontext) {
1032
			struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1033 1034 1035
			newisec->sid = sid;
		}
		newsbsec->mntpoint_sid = sid;
L
Linus Torvalds 已提交
1036
	}
1037
	if (set_rootcontext) {
1038 1039
		const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
		struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
L
Linus Torvalds 已提交
1040

1041
		newisec->sid = oldisec->sid;
L
Linus Torvalds 已提交
1042 1043
	}

1044
	sb_finish_set_opts(newsb);
1045
out:
1046
	mutex_unlock(&newsbsec->lock);
1047
	return rc;
1048 1049
}

1050 1051
static int selinux_parse_opts_str(char *options,
				  struct security_mnt_opts *opts)
1052
{
1053
	char *p;
1054 1055
	char *context = NULL, *defcontext = NULL;
	char *fscontext = NULL, *rootcontext = NULL;
1056
	int rc, num_mnt_opts = 0;
L
Linus Torvalds 已提交
1057

1058
	opts->num_mnt_opts = 0;
L
Linus Torvalds 已提交
1059

1060 1061 1062 1063
	/* Standard string-based options. */
	while ((p = strsep(&options, "|")) != NULL) {
		int token;
		substring_t args[MAX_OPT_ARGS];
L
Linus Torvalds 已提交
1064

1065 1066
		if (!*p)
			continue;
L
Linus Torvalds 已提交
1067

1068
		token = match_token(p, tokens, args);
L
Linus Torvalds 已提交
1069

1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121
		switch (token) {
		case Opt_context:
			if (context || defcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			context = match_strdup(&args[0]);
			if (!context) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		case Opt_fscontext:
			if (fscontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			fscontext = match_strdup(&args[0]);
			if (!fscontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		case Opt_rootcontext:
			if (rootcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			rootcontext = match_strdup(&args[0]);
			if (!rootcontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;

		case Opt_defcontext:
			if (context || defcontext) {
				rc = -EINVAL;
				printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
				goto out_err;
			}
			defcontext = match_strdup(&args[0]);
			if (!defcontext) {
				rc = -ENOMEM;
				goto out_err;
			}
			break;
1122 1123
		case Opt_labelsupport:
			break;
1124 1125 1126 1127
		default:
			rc = -EINVAL;
			printk(KERN_WARNING "SELinux:  unknown mount option\n");
			goto out_err;
L
Linus Torvalds 已提交
1128 1129 1130

		}
	}
1131

1132
	rc = -ENOMEM;
1133
	opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
1134 1135 1136
	if (!opts->mnt_opts)
		goto out_err;

1137 1138
	opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
				       GFP_KERNEL);
1139
	if (!opts->mnt_opts_flags)
1140 1141
		goto out_err;

1142
	if (fscontext) {
1143 1144
		opts->mnt_opts[num_mnt_opts] = fscontext;
		opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1145 1146
	}
	if (context) {
1147 1148
		opts->mnt_opts[num_mnt_opts] = context;
		opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1149 1150
	}
	if (rootcontext) {
1151 1152
		opts->mnt_opts[num_mnt_opts] = rootcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1153 1154
	}
	if (defcontext) {
1155 1156
		opts->mnt_opts[num_mnt_opts] = defcontext;
		opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1157 1158
	}

1159 1160 1161
	opts->num_mnt_opts = num_mnt_opts;
	return 0;

1162
out_err:
1163
	security_free_mnt_opts(opts);
1164 1165 1166 1167
	kfree(context);
	kfree(defcontext);
	kfree(fscontext);
	kfree(rootcontext);
L
Linus Torvalds 已提交
1168 1169
	return rc;
}
1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190
/*
 * string mount options parsing and call set the sbsec
 */
static int superblock_doinit(struct super_block *sb, void *data)
{
	int rc = 0;
	char *options = data;
	struct security_mnt_opts opts;

	security_init_mnt_opts(&opts);

	if (!data)
		goto out;

	BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);

	rc = selinux_parse_opts_str(options, &opts);
	if (rc)
		goto out_err;

out:
1191
	rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1192 1193 1194 1195 1196

out_err:
	security_free_mnt_opts(&opts);
	return rc;
}
L
Linus Torvalds 已提交
1197

A
Adrian Bunk 已提交
1198 1199
static void selinux_write_opts(struct seq_file *m,
			       struct security_mnt_opts *opts)
1200 1201 1202 1203 1204
{
	int i;
	char *prefix;

	for (i = 0; i < opts->num_mnt_opts; i++) {
1205 1206 1207 1208 1209 1210
		char *has_comma;

		if (opts->mnt_opts[i])
			has_comma = strchr(opts->mnt_opts[i], ',');
		else
			has_comma = NULL;
1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224

		switch (opts->mnt_opts_flags[i]) {
		case CONTEXT_MNT:
			prefix = CONTEXT_STR;
			break;
		case FSCONTEXT_MNT:
			prefix = FSCONTEXT_STR;
			break;
		case ROOTCONTEXT_MNT:
			prefix = ROOTCONTEXT_STR;
			break;
		case DEFCONTEXT_MNT:
			prefix = DEFCONTEXT_STR;
			break;
1225
		case SBLABEL_MNT:
1226 1227 1228
			seq_putc(m, ',');
			seq_puts(m, LABELSUPP_STR);
			continue;
1229 1230
		default:
			BUG();
1231
			return;
1232 1233 1234 1235 1236 1237
		};
		/* we need a comma before each option */
		seq_putc(m, ',');
		seq_puts(m, prefix);
		if (has_comma)
			seq_putc(m, '\"');
1238
		seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249
		if (has_comma)
			seq_putc(m, '\"');
	}
}

static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
{
	struct security_mnt_opts opts;
	int rc;

	rc = selinux_get_mnt_opts(sb, &opts);
1250 1251 1252 1253
	if (rc) {
		/* before policy load we may get EINVAL, don't show anything */
		if (rc == -EINVAL)
			rc = 0;
1254
		return rc;
1255
	}
1256 1257 1258 1259 1260 1261 1262 1263

	selinux_write_opts(m, &opts);

	security_free_mnt_opts(&opts);

	return rc;
}

L
Linus Torvalds 已提交
1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286
static inline u16 inode_mode_to_security_class(umode_t mode)
{
	switch (mode & S_IFMT) {
	case S_IFSOCK:
		return SECCLASS_SOCK_FILE;
	case S_IFLNK:
		return SECCLASS_LNK_FILE;
	case S_IFREG:
		return SECCLASS_FILE;
	case S_IFBLK:
		return SECCLASS_BLK_FILE;
	case S_IFDIR:
		return SECCLASS_DIR;
	case S_IFCHR:
		return SECCLASS_CHR_FILE;
	case S_IFIFO:
		return SECCLASS_FIFO_FILE;

	}

	return SECCLASS_FILE;
}

1287 1288 1289 1290 1291 1292 1293 1294 1295 1296
static inline int default_protocol_stream(int protocol)
{
	return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
}

static inline int default_protocol_dgram(int protocol)
{
	return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
}

L
Linus Torvalds 已提交
1297 1298
static inline u16 socket_type_to_security_class(int family, int type, int protocol)
{
1299 1300
	int extsockclass = selinux_policycap_extsockclass;

L
Linus Torvalds 已提交
1301 1302 1303 1304 1305 1306 1307
	switch (family) {
	case PF_UNIX:
		switch (type) {
		case SOCK_STREAM:
		case SOCK_SEQPACKET:
			return SECCLASS_UNIX_STREAM_SOCKET;
		case SOCK_DGRAM:
1308
		case SOCK_RAW:
L
Linus Torvalds 已提交
1309 1310 1311 1312 1313 1314 1315
			return SECCLASS_UNIX_DGRAM_SOCKET;
		}
		break;
	case PF_INET:
	case PF_INET6:
		switch (type) {
		case SOCK_STREAM:
1316
		case SOCK_SEQPACKET:
1317 1318
			if (default_protocol_stream(protocol))
				return SECCLASS_TCP_SOCKET;
1319 1320
			else if (extsockclass && protocol == IPPROTO_SCTP)
				return SECCLASS_SCTP_SOCKET;
1321 1322
			else
				return SECCLASS_RAWIP_SOCKET;
L
Linus Torvalds 已提交
1323
		case SOCK_DGRAM:
1324 1325
			if (default_protocol_dgram(protocol))
				return SECCLASS_UDP_SOCKET;
1326 1327
			else if (extsockclass && (protocol == IPPROTO_ICMP ||
						  protocol == IPPROTO_ICMPV6))
1328
				return SECCLASS_ICMP_SOCKET;
1329 1330
			else
				return SECCLASS_RAWIP_SOCKET;
J
James Morris 已提交
1331 1332
		case SOCK_DCCP:
			return SECCLASS_DCCP_SOCKET;
1333
		default:
L
Linus Torvalds 已提交
1334 1335 1336 1337 1338 1339 1340
			return SECCLASS_RAWIP_SOCKET;
		}
		break;
	case PF_NETLINK:
		switch (protocol) {
		case NETLINK_ROUTE:
			return SECCLASS_NETLINK_ROUTE_SOCKET;
1341
		case NETLINK_SOCK_DIAG:
L
Linus Torvalds 已提交
1342 1343 1344 1345 1346 1347 1348
			return SECCLASS_NETLINK_TCPDIAG_SOCKET;
		case NETLINK_NFLOG:
			return SECCLASS_NETLINK_NFLOG_SOCKET;
		case NETLINK_XFRM:
			return SECCLASS_NETLINK_XFRM_SOCKET;
		case NETLINK_SELINUX:
			return SECCLASS_NETLINK_SELINUX_SOCKET;
1349 1350
		case NETLINK_ISCSI:
			return SECCLASS_NETLINK_ISCSI_SOCKET;
L
Linus Torvalds 已提交
1351 1352
		case NETLINK_AUDIT:
			return SECCLASS_NETLINK_AUDIT_SOCKET;
1353 1354 1355 1356 1357 1358
		case NETLINK_FIB_LOOKUP:
			return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
		case NETLINK_CONNECTOR:
			return SECCLASS_NETLINK_CONNECTOR_SOCKET;
		case NETLINK_NETFILTER:
			return SECCLASS_NETLINK_NETFILTER_SOCKET;
L
Linus Torvalds 已提交
1359 1360
		case NETLINK_DNRTMSG:
			return SECCLASS_NETLINK_DNRT_SOCKET;
1361 1362
		case NETLINK_KOBJECT_UEVENT:
			return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1363 1364 1365 1366 1367 1368 1369 1370
		case NETLINK_GENERIC:
			return SECCLASS_NETLINK_GENERIC_SOCKET;
		case NETLINK_SCSITRANSPORT:
			return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
		case NETLINK_RDMA:
			return SECCLASS_NETLINK_RDMA_SOCKET;
		case NETLINK_CRYPTO:
			return SECCLASS_NETLINK_CRYPTO_SOCKET;
L
Linus Torvalds 已提交
1371 1372 1373 1374 1375 1376 1377
		default:
			return SECCLASS_NETLINK_SOCKET;
		}
	case PF_PACKET:
		return SECCLASS_PACKET_SOCKET;
	case PF_KEY:
		return SECCLASS_KEY_SOCKET;
1378 1379
	case PF_APPLETALK:
		return SECCLASS_APPLETALK_SOCKET;
L
Linus Torvalds 已提交
1380 1381
	}

1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435
	if (extsockclass) {
		switch (family) {
		case PF_AX25:
			return SECCLASS_AX25_SOCKET;
		case PF_IPX:
			return SECCLASS_IPX_SOCKET;
		case PF_NETROM:
			return SECCLASS_NETROM_SOCKET;
		case PF_ATMPVC:
			return SECCLASS_ATMPVC_SOCKET;
		case PF_X25:
			return SECCLASS_X25_SOCKET;
		case PF_ROSE:
			return SECCLASS_ROSE_SOCKET;
		case PF_DECnet:
			return SECCLASS_DECNET_SOCKET;
		case PF_ATMSVC:
			return SECCLASS_ATMSVC_SOCKET;
		case PF_RDS:
			return SECCLASS_RDS_SOCKET;
		case PF_IRDA:
			return SECCLASS_IRDA_SOCKET;
		case PF_PPPOX:
			return SECCLASS_PPPOX_SOCKET;
		case PF_LLC:
			return SECCLASS_LLC_SOCKET;
		case PF_CAN:
			return SECCLASS_CAN_SOCKET;
		case PF_TIPC:
			return SECCLASS_TIPC_SOCKET;
		case PF_BLUETOOTH:
			return SECCLASS_BLUETOOTH_SOCKET;
		case PF_IUCV:
			return SECCLASS_IUCV_SOCKET;
		case PF_RXRPC:
			return SECCLASS_RXRPC_SOCKET;
		case PF_ISDN:
			return SECCLASS_ISDN_SOCKET;
		case PF_PHONET:
			return SECCLASS_PHONET_SOCKET;
		case PF_IEEE802154:
			return SECCLASS_IEEE802154_SOCKET;
		case PF_CAIF:
			return SECCLASS_CAIF_SOCKET;
		case PF_ALG:
			return SECCLASS_ALG_SOCKET;
		case PF_NFC:
			return SECCLASS_NFC_SOCKET;
		case PF_VSOCK:
			return SECCLASS_VSOCK_SOCKET;
		case PF_KCM:
			return SECCLASS_KCM_SOCKET;
		case PF_QIPCRTR:
			return SECCLASS_QIPCRTR_SOCKET;
1436 1437 1438
		case PF_SMC:
			return SECCLASS_SMC_SOCKET;
#if PF_MAX > 44
1439 1440 1441 1442 1443
#error New address family defined, please update this function.
#endif
		}
	}

L
Linus Torvalds 已提交
1444 1445 1446
	return SECCLASS_SOCKET;
}

1447 1448 1449 1450
static int selinux_genfs_get_sid(struct dentry *dentry,
				 u16 tclass,
				 u16 flags,
				 u32 *sid)
L
Linus Torvalds 已提交
1451
{
1452
	int rc;
1453
	struct super_block *sb = dentry->d_sb;
1454
	char *buffer, *path;
L
Linus Torvalds 已提交
1455

1456
	buffer = (char *)__get_free_page(GFP_KERNEL);
L
Linus Torvalds 已提交
1457 1458 1459
	if (!buffer)
		return -ENOMEM;

1460 1461 1462 1463
	path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
	if (IS_ERR(path))
		rc = PTR_ERR(path);
	else {
1464 1465 1466 1467 1468 1469 1470 1471
		if (flags & SE_SBPROC) {
			/* each process gets a /proc/PID/ entry. Strip off the
			 * PID part to get a valid selinux labeling.
			 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
			while (path[1] >= '0' && path[1] <= '9') {
				path[1] = '/';
				path++;
			}
1472
		}
1473
		rc = security_genfs_sid(sb->s_type->name, path, tclass, sid);
L
Linus Torvalds 已提交
1474 1475 1476 1477 1478 1479 1480 1481 1482 1483
	}
	free_page((unsigned long)buffer);
	return rc;
}

/* The inode's security attributes must be initialized before first use. */
static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
{
	struct superblock_security_struct *sbsec = NULL;
	struct inode_security_struct *isec = inode->i_security;
1484 1485
	u32 task_sid, sid = 0;
	u16 sclass;
L
Linus Torvalds 已提交
1486 1487 1488 1489 1490 1491
	struct dentry *dentry;
#define INITCONTEXTLEN 255
	char *context = NULL;
	unsigned len = 0;
	int rc = 0;

1492
	if (isec->initialized == LABEL_INITIALIZED)
1493
		return 0;
L
Linus Torvalds 已提交
1494

1495
	spin_lock(&isec->lock);
1496
	if (isec->initialized == LABEL_INITIALIZED)
1497
		goto out_unlock;
L
Linus Torvalds 已提交
1498

1499 1500 1501
	if (isec->sclass == SECCLASS_FILE)
		isec->sclass = inode_mode_to_security_class(inode->i_mode);

L
Linus Torvalds 已提交
1502
	sbsec = inode->i_sb->s_security;
1503
	if (!(sbsec->flags & SE_SBINITIALIZED)) {
L
Linus Torvalds 已提交
1504 1505 1506 1507 1508 1509 1510
		/* Defer initialization until selinux_complete_init,
		   after the initial policy is loaded and the security
		   server is ready to handle calls. */
		spin_lock(&sbsec->isec_lock);
		if (list_empty(&isec->list))
			list_add(&isec->list, &sbsec->isec_head);
		spin_unlock(&sbsec->isec_lock);
1511
		goto out_unlock;
L
Linus Torvalds 已提交
1512 1513
	}

1514 1515 1516 1517 1518 1519
	sclass = isec->sclass;
	task_sid = isec->task_sid;
	sid = isec->sid;
	isec->initialized = LABEL_PENDING;
	spin_unlock(&isec->lock);

L
Linus Torvalds 已提交
1520
	switch (sbsec->behavior) {
1521 1522
	case SECURITY_FS_USE_NATIVE:
		break;
L
Linus Torvalds 已提交
1523
	case SECURITY_FS_USE_XATTR:
1524
		if (!(inode->i_opflags & IOP_XATTR)) {
1525
			sid = sbsec->def_sid;
L
Linus Torvalds 已提交
1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537
			break;
		}
		/* Need a dentry, since the xattr API requires one.
		   Life would be simpler if we could just pass the inode. */
		if (opt_dentry) {
			/* Called from d_instantiate or d_splice_alias. */
			dentry = dget(opt_dentry);
		} else {
			/* Called from selinux_complete_init, try to find a dentry. */
			dentry = d_find_alias(inode);
		}
		if (!dentry) {
1538 1539 1540 1541 1542 1543 1544 1545 1546
			/*
			 * this is can be hit on boot when a file is accessed
			 * before the policy is loaded.  When we load policy we
			 * may find inodes that have no dentry on the
			 * sbsec->isec_head list.  No reason to complain as these
			 * will get fixed up the next time we go through
			 * inode_doinit with a dentry, before these inodes could
			 * be used again by userspace.
			 */
1547
			goto out;
L
Linus Torvalds 已提交
1548 1549 1550
		}

		len = INITCONTEXTLEN;
1551
		context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1552 1553 1554
		if (!context) {
			rc = -ENOMEM;
			dput(dentry);
1555
			goto out;
L
Linus Torvalds 已提交
1556
		}
1557
		context[len] = '\0';
1558
		rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
L
Linus Torvalds 已提交
1559
		if (rc == -ERANGE) {
1560 1561
			kfree(context);

L
Linus Torvalds 已提交
1562
			/* Need a larger buffer.  Query for the right size. */
1563
			rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
L
Linus Torvalds 已提交
1564 1565
			if (rc < 0) {
				dput(dentry);
1566
				goto out;
L
Linus Torvalds 已提交
1567 1568
			}
			len = rc;
1569
			context = kmalloc(len+1, GFP_NOFS);
L
Linus Torvalds 已提交
1570 1571 1572
			if (!context) {
				rc = -ENOMEM;
				dput(dentry);
1573
				goto out;
L
Linus Torvalds 已提交
1574
			}
1575
			context[len] = '\0';
1576
			rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
L
Linus Torvalds 已提交
1577 1578 1579 1580
		}
		dput(dentry);
		if (rc < 0) {
			if (rc != -ENODATA) {
E
Eric Paris 已提交
1581
				printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1582
				       "%d for dev=%s ino=%ld\n", __func__,
L
Linus Torvalds 已提交
1583 1584
				       -rc, inode->i_sb->s_id, inode->i_ino);
				kfree(context);
1585
				goto out;
L
Linus Torvalds 已提交
1586 1587 1588 1589 1590
			}
			/* Map ENODATA to the default file SID */
			sid = sbsec->def_sid;
			rc = 0;
		} else {
1591
			rc = security_context_to_sid_default(context, rc, &sid,
1592 1593
							     sbsec->def_sid,
							     GFP_NOFS);
L
Linus Torvalds 已提交
1594
			if (rc) {
1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607
				char *dev = inode->i_sb->s_id;
				unsigned long ino = inode->i_ino;

				if (rc == -EINVAL) {
					if (printk_ratelimit())
						printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
							"context=%s.  This indicates you may need to relabel the inode or the "
							"filesystem in question.\n", ino, dev, context);
				} else {
					printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
					       "returned %d for dev=%s ino=%ld\n",
					       __func__, context, -rc, dev, ino);
				}
L
Linus Torvalds 已提交
1608 1609 1610 1611 1612 1613 1614 1615 1616
				kfree(context);
				/* Leave with the unlabeled SID */
				rc = 0;
				break;
			}
		}
		kfree(context);
		break;
	case SECURITY_FS_USE_TASK:
1617
		sid = task_sid;
L
Linus Torvalds 已提交
1618 1619 1620
		break;
	case SECURITY_FS_USE_TRANS:
		/* Default to the fs SID. */
1621
		sid = sbsec->sid;
L
Linus Torvalds 已提交
1622 1623

		/* Try to obtain a transition SID. */
1624
		rc = security_transition_sid(task_sid, sid, sclass, NULL, &sid);
L
Linus Torvalds 已提交
1625
		if (rc)
1626
			goto out;
L
Linus Torvalds 已提交
1627
		break;
1628
	case SECURITY_FS_USE_MNTPOINT:
1629
		sid = sbsec->mntpoint_sid;
1630
		break;
L
Linus Torvalds 已提交
1631
	default:
1632
		/* Default to the fs superblock SID. */
1633
		sid = sbsec->sid;
L
Linus Torvalds 已提交
1634

1635
		if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655
			/* We must have a dentry to determine the label on
			 * procfs inodes */
			if (opt_dentry)
				/* Called from d_instantiate or
				 * d_splice_alias. */
				dentry = dget(opt_dentry);
			else
				/* Called from selinux_complete_init, try to
				 * find a dentry. */
				dentry = d_find_alias(inode);
			/*
			 * This can be hit on boot when a file is accessed
			 * before the policy is loaded.  When we load policy we
			 * may find inodes that have no dentry on the
			 * sbsec->isec_head list.  No reason to complain as
			 * these will get fixed up the next time we go through
			 * inode_doinit() with a dentry, before these inodes
			 * could be used again by userspace.
			 */
			if (!dentry)
1656 1657
				goto out;
			rc = selinux_genfs_get_sid(dentry, sclass,
1658
						   sbsec->flags, &sid);
1659 1660
			dput(dentry);
			if (rc)
1661
				goto out;
L
Linus Torvalds 已提交
1662 1663 1664 1665
		}
		break;
	}

1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676
out:
	spin_lock(&isec->lock);
	if (isec->initialized == LABEL_PENDING) {
		if (!sid || rc) {
			isec->initialized = LABEL_INVALID;
			goto out_unlock;
		}

		isec->initialized = LABEL_INITIALIZED;
		isec->sid = sid;
	}
L
Linus Torvalds 已提交
1677

1678
out_unlock:
1679
	spin_unlock(&isec->lock);
L
Linus Torvalds 已提交
1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709
	return rc;
}

/* Convert a Linux signal to an access vector. */
static inline u32 signal_to_av(int sig)
{
	u32 perm = 0;

	switch (sig) {
	case SIGCHLD:
		/* Commonly granted from child to parent. */
		perm = PROCESS__SIGCHLD;
		break;
	case SIGKILL:
		/* Cannot be caught or ignored */
		perm = PROCESS__SIGKILL;
		break;
	case SIGSTOP:
		/* Cannot be caught or ignored */
		perm = PROCESS__SIGSTOP;
		break;
	default:
		/* All other signals. */
		perm = PROCESS__SIGNAL;
		break;
	}

	return perm;
}

1710 1711 1712 1713
#if CAP_LAST_CAP > 63
#error Fix SELinux to handle capabilities > 63.
#endif

L
Linus Torvalds 已提交
1714
/* Check whether a task is allowed to use a capability. */
1715
static int cred_has_capability(const struct cred *cred,
1716
			       int cap, int audit, bool initns)
L
Linus Torvalds 已提交
1717
{
1718
	struct common_audit_data ad;
1719
	struct av_decision avd;
1720
	u16 sclass;
1721
	u32 sid = cred_sid(cred);
1722
	u32 av = CAP_TO_MASK(cap);
1723
	int rc;
L
Linus Torvalds 已提交
1724

1725
	ad.type = LSM_AUDIT_DATA_CAP;
L
Linus Torvalds 已提交
1726 1727
	ad.u.cap = cap;

1728 1729
	switch (CAP_TO_INDEX(cap)) {
	case 0:
1730
		sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1731 1732
		break;
	case 1:
1733
		sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1734 1735 1736 1737 1738
		break;
	default:
		printk(KERN_ERR
		       "SELinux:  out of range capability %d\n", cap);
		BUG();
1739
		return -EINVAL;
1740
	}
1741

1742
	rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1743
	if (audit == SECURITY_CAP_AUDIT) {
1744
		int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1745 1746 1747
		if (rc2)
			return rc2;
	}
1748
	return rc;
L
Linus Torvalds 已提交
1749 1750 1751 1752 1753
}

/* Check whether a task has a particular permission to an inode.
   The 'adp' parameter is optional and allows other audit
   data to be passed (e.g. the dentry). */
1754
static int inode_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1755 1756
			  struct inode *inode,
			  u32 perms,
1757
			  struct common_audit_data *adp)
L
Linus Torvalds 已提交
1758 1759
{
	struct inode_security_struct *isec;
1760
	u32 sid;
L
Linus Torvalds 已提交
1761

1762 1763
	validate_creds(cred);

1764
	if (unlikely(IS_PRIVATE(inode)))
1765 1766
		return 0;

1767
	sid = cred_sid(cred);
L
Linus Torvalds 已提交
1768 1769
	isec = inode->i_security;

1770
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
L
Linus Torvalds 已提交
1771 1772 1773 1774 1775
}

/* Same as inode_has_perm, but pass explicit audit data containing
   the dentry to help the auditing code to more easily generate the
   pathname if needed. */
1776
static inline int dentry_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
1777 1778 1779
				  struct dentry *dentry,
				  u32 av)
{
1780
	struct inode *inode = d_backing_inode(dentry);
1781
	struct common_audit_data ad;
1782

1783
	ad.type = LSM_AUDIT_DATA_DENTRY;
E
Eric Paris 已提交
1784
	ad.u.dentry = dentry;
1785
	__inode_security_revalidate(inode, dentry, true);
1786
	return inode_has_perm(cred, inode, av, &ad);
E
Eric Paris 已提交
1787 1788 1789 1790 1791 1792
}

/* Same as inode_has_perm, but pass explicit audit data containing
   the path to help the auditing code to more easily generate the
   pathname if needed. */
static inline int path_has_perm(const struct cred *cred,
1793
				const struct path *path,
E
Eric Paris 已提交
1794 1795
				u32 av)
{
1796
	struct inode *inode = d_backing_inode(path->dentry);
E
Eric Paris 已提交
1797 1798
	struct common_audit_data ad;

1799
	ad.type = LSM_AUDIT_DATA_PATH;
E
Eric Paris 已提交
1800
	ad.u.path = *path;
1801
	__inode_security_revalidate(inode, path->dentry, true);
1802
	return inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1803 1804
}

1805 1806 1807 1808 1809 1810 1811
/* Same as path_has_perm, but uses the inode from the file struct. */
static inline int file_path_has_perm(const struct cred *cred,
				     struct file *file,
				     u32 av)
{
	struct common_audit_data ad;

1812 1813
	ad.type = LSM_AUDIT_DATA_FILE;
	ad.u.file = file;
1814
	return inode_has_perm(cred, file_inode(file), av, &ad);
1815 1816
}

L
Linus Torvalds 已提交
1817 1818 1819 1820 1821 1822 1823 1824
/* Check whether a task can use an open file descriptor to
   access an inode in a given way.  Check access to the
   descriptor itself, and then use dentry_has_perm to
   check a particular permission to the file.
   Access to the descriptor is implicitly granted if it
   has the same SID as the process.  If av is zero, then
   access to the file is not checked, e.g. for cases
   where only the descriptor is affected like seek. */
1825 1826 1827
static int file_has_perm(const struct cred *cred,
			 struct file *file,
			 u32 av)
L
Linus Torvalds 已提交
1828 1829
{
	struct file_security_struct *fsec = file->f_security;
A
Al Viro 已提交
1830
	struct inode *inode = file_inode(file);
1831
	struct common_audit_data ad;
1832
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
1833 1834
	int rc;

1835 1836
	ad.type = LSM_AUDIT_DATA_FILE;
	ad.u.file = file;
L
Linus Torvalds 已提交
1837

1838 1839
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
L
Linus Torvalds 已提交
1840 1841 1842 1843
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
1844
			goto out;
L
Linus Torvalds 已提交
1845 1846 1847
	}

	/* av is zero if only checking access to the descriptor. */
1848
	rc = 0;
L
Linus Torvalds 已提交
1849
	if (av)
1850
		rc = inode_has_perm(cred, inode, av, &ad);
L
Linus Torvalds 已提交
1851

1852 1853
out:
	return rc;
L
Linus Torvalds 已提交
1854 1855
}

1856 1857 1858
/*
 * Determine the label for an inode that might be unioned.
 */
1859 1860 1861 1862 1863
static int
selinux_determine_inode_label(const struct task_security_struct *tsec,
				 struct inode *dir,
				 const struct qstr *name, u16 tclass,
				 u32 *_new_isid)
1864 1865 1866 1867 1868 1869 1870 1871 1872 1873
{
	const struct superblock_security_struct *sbsec = dir->i_sb->s_security;

	if ((sbsec->flags & SE_SBINITIALIZED) &&
	    (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
		*_new_isid = sbsec->mntpoint_sid;
	} else if ((sbsec->flags & SBLABEL_MNT) &&
		   tsec->create_sid) {
		*_new_isid = tsec->create_sid;
	} else {
1874
		const struct inode_security_struct *dsec = inode_security(dir);
1875 1876 1877 1878 1879 1880 1881
		return security_transition_sid(tsec->sid, dsec->sid, tclass,
					       name, _new_isid);
	}

	return 0;
}

L
Linus Torvalds 已提交
1882 1883 1884 1885 1886
/* Check whether a task can create a file. */
static int may_create(struct inode *dir,
		      struct dentry *dentry,
		      u16 tclass)
{
1887
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
1888 1889
	struct inode_security_struct *dsec;
	struct superblock_security_struct *sbsec;
1890
	u32 sid, newsid;
1891
	struct common_audit_data ad;
L
Linus Torvalds 已提交
1892 1893
	int rc;

1894
	dsec = inode_security(dir);
L
Linus Torvalds 已提交
1895 1896
	sbsec = dir->i_sb->s_security;

1897 1898
	sid = tsec->sid;

1899
	ad.type = LSM_AUDIT_DATA_DENTRY;
1900
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1901

1902
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1903 1904 1905 1906 1907
			  DIR__ADD_NAME | DIR__SEARCH,
			  &ad);
	if (rc)
		return rc;

1908 1909
	rc = selinux_determine_inode_label(current_security(), dir,
					   &dentry->d_name, tclass, &newsid);
1910 1911
	if (rc)
		return rc;
L
Linus Torvalds 已提交
1912

1913
	rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
L
Linus Torvalds 已提交
1914 1915 1916 1917 1918 1919 1920 1921
	if (rc)
		return rc;

	return avc_has_perm(newsid, sbsec->sid,
			    SECCLASS_FILESYSTEM,
			    FILESYSTEM__ASSOCIATE, &ad);
}

1922 1923 1924
#define MAY_LINK	0
#define MAY_UNLINK	1
#define MAY_RMDIR	2
L
Linus Torvalds 已提交
1925 1926 1927 1928 1929 1930 1931 1932

/* Check whether a task can link, unlink, or rmdir a file/directory. */
static int may_link(struct inode *dir,
		    struct dentry *dentry,
		    int kind)

{
	struct inode_security_struct *dsec, *isec;
1933
	struct common_audit_data ad;
1934
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1935 1936 1937
	u32 av;
	int rc;

1938 1939
	dsec = inode_security(dir);
	isec = backing_inode_security(dentry);
L
Linus Torvalds 已提交
1940

1941
	ad.type = LSM_AUDIT_DATA_DENTRY;
1942
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
1943 1944 1945

	av = DIR__SEARCH;
	av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1946
	rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960
	if (rc)
		return rc;

	switch (kind) {
	case MAY_LINK:
		av = FILE__LINK;
		break;
	case MAY_UNLINK:
		av = FILE__UNLINK;
		break;
	case MAY_RMDIR:
		av = DIR__RMDIR;
		break;
	default:
E
Eric Paris 已提交
1961 1962
		printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
			__func__, kind);
L
Linus Torvalds 已提交
1963 1964 1965
		return 0;
	}

1966
	rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
L
Linus Torvalds 已提交
1967 1968 1969 1970 1971 1972 1973 1974 1975
	return rc;
}

static inline int may_rename(struct inode *old_dir,
			     struct dentry *old_dentry,
			     struct inode *new_dir,
			     struct dentry *new_dentry)
{
	struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1976
	struct common_audit_data ad;
1977
	u32 sid = current_sid();
L
Linus Torvalds 已提交
1978 1979 1980 1981
	u32 av;
	int old_is_dir, new_is_dir;
	int rc;

1982 1983
	old_dsec = inode_security(old_dir);
	old_isec = backing_inode_security(old_dentry);
1984
	old_is_dir = d_is_dir(old_dentry);
1985
	new_dsec = inode_security(new_dir);
L
Linus Torvalds 已提交
1986

1987
	ad.type = LSM_AUDIT_DATA_DENTRY;
L
Linus Torvalds 已提交
1988

1989
	ad.u.dentry = old_dentry;
1990
	rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
L
Linus Torvalds 已提交
1991 1992 1993
			  DIR__REMOVE_NAME | DIR__SEARCH, &ad);
	if (rc)
		return rc;
1994
	rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
1995 1996 1997 1998
			  old_isec->sclass, FILE__RENAME, &ad);
	if (rc)
		return rc;
	if (old_is_dir && new_dir != old_dir) {
1999
		rc = avc_has_perm(sid, old_isec->sid,
L
Linus Torvalds 已提交
2000 2001 2002 2003 2004
				  old_isec->sclass, DIR__REPARENT, &ad);
		if (rc)
			return rc;
	}

2005
	ad.u.dentry = new_dentry;
L
Linus Torvalds 已提交
2006
	av = DIR__ADD_NAME | DIR__SEARCH;
2007
	if (d_is_positive(new_dentry))
L
Linus Torvalds 已提交
2008
		av |= DIR__REMOVE_NAME;
2009
	rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
L
Linus Torvalds 已提交
2010 2011
	if (rc)
		return rc;
2012
	if (d_is_positive(new_dentry)) {
2013
		new_isec = backing_inode_security(new_dentry);
2014
		new_is_dir = d_is_dir(new_dentry);
2015
		rc = avc_has_perm(sid, new_isec->sid,
L
Linus Torvalds 已提交
2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
				  new_isec->sclass,
				  (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
		if (rc)
			return rc;
	}

	return 0;
}

/* Check whether a task can perform a filesystem operation. */
2026
static int superblock_has_perm(const struct cred *cred,
L
Linus Torvalds 已提交
2027 2028
			       struct super_block *sb,
			       u32 perms,
2029
			       struct common_audit_data *ad)
L
Linus Torvalds 已提交
2030 2031
{
	struct superblock_security_struct *sbsec;
2032
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
2033 2034

	sbsec = sb->s_security;
2035
	return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
L
Linus Torvalds 已提交
2036 2037 2038 2039 2040 2041 2042
}

/* Convert a Linux mode and permission mask to an access vector. */
static inline u32 file_mask_to_av(int mode, int mask)
{
	u32 av = 0;

A
Al Viro 已提交
2043
	if (!S_ISDIR(mode)) {
L
Linus Torvalds 已提交
2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065
		if (mask & MAY_EXEC)
			av |= FILE__EXECUTE;
		if (mask & MAY_READ)
			av |= FILE__READ;

		if (mask & MAY_APPEND)
			av |= FILE__APPEND;
		else if (mask & MAY_WRITE)
			av |= FILE__WRITE;

	} else {
		if (mask & MAY_EXEC)
			av |= DIR__SEARCH;
		if (mask & MAY_WRITE)
			av |= DIR__WRITE;
		if (mask & MAY_READ)
			av |= DIR__READ;
	}

	return av;
}

2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088
/* Convert a Linux file to an access vector. */
static inline u32 file_to_av(struct file *file)
{
	u32 av = 0;

	if (file->f_mode & FMODE_READ)
		av |= FILE__READ;
	if (file->f_mode & FMODE_WRITE) {
		if (file->f_flags & O_APPEND)
			av |= FILE__APPEND;
		else
			av |= FILE__WRITE;
	}
	if (!av) {
		/*
		 * Special file opened with flags 3 for ioctl-only use.
		 */
		av = FILE__IOCTL;
	}

	return av;
}

E
Eric Paris 已提交
2089
/*
2090
 * Convert a file to an access vector and include the correct open
E
Eric Paris 已提交
2091 2092
 * open permission.
 */
2093
static inline u32 open_file_to_av(struct file *file)
E
Eric Paris 已提交
2094
{
2095
	u32 av = file_to_av(file);
2096
	struct inode *inode = file_inode(file);
E
Eric Paris 已提交
2097

2098
	if (selinux_policycap_openperm && inode->i_sb->s_magic != SOCKFS_MAGIC)
2099 2100
		av |= FILE__OPEN;

E
Eric Paris 已提交
2101 2102 2103
	return av;
}

L
Linus Torvalds 已提交
2104 2105
/* Hook functions begin here. */

2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149
static int selinux_binder_set_context_mgr(struct task_struct *mgr)
{
	u32 mysid = current_sid();
	u32 mgrsid = task_sid(mgr);

	return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER,
			    BINDER__SET_CONTEXT_MGR, NULL);
}

static int selinux_binder_transaction(struct task_struct *from,
				      struct task_struct *to)
{
	u32 mysid = current_sid();
	u32 fromsid = task_sid(from);
	u32 tosid = task_sid(to);
	int rc;

	if (mysid != fromsid) {
		rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
				  BINDER__IMPERSONATE, NULL);
		if (rc)
			return rc;
	}

	return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
			    NULL);
}

static int selinux_binder_transfer_binder(struct task_struct *from,
					  struct task_struct *to)
{
	u32 fromsid = task_sid(from);
	u32 tosid = task_sid(to);

	return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
			    NULL);
}

static int selinux_binder_transfer_file(struct task_struct *from,
					struct task_struct *to,
					struct file *file)
{
	u32 sid = task_sid(to);
	struct file_security_struct *fsec = file->f_security;
2150
	struct dentry *dentry = file->f_path.dentry;
2151
	struct inode_security_struct *isec;
2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166
	struct common_audit_data ad;
	int rc;

	ad.type = LSM_AUDIT_DATA_PATH;
	ad.u.path = file->f_path;

	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid,
				  SECCLASS_FD,
				  FD__USE,
				  &ad);
		if (rc)
			return rc;
	}

2167
	if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2168 2169
		return 0;

2170
	isec = backing_inode_security(dentry);
2171 2172 2173 2174
	return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
			    &ad);
}

2175
static int selinux_ptrace_access_check(struct task_struct *child,
2176
				     unsigned int mode)
L
Linus Torvalds 已提交
2177
{
2178 2179 2180 2181
	u32 sid = current_sid();
	u32 csid = task_sid(child);

	if (mode & PTRACE_MODE_READ)
2182
		return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2183

2184
	return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2185 2186 2187 2188
}

static int selinux_ptrace_traceme(struct task_struct *parent)
{
2189 2190
	return avc_has_perm(task_sid(parent), current_sid(), SECCLASS_PROCESS,
			    PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
2191 2192 2193
}

static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2194
			  kernel_cap_t *inheritable, kernel_cap_t *permitted)
L
Linus Torvalds 已提交
2195
{
2196 2197
	return avc_has_perm(current_sid(), task_sid(target), SECCLASS_PROCESS,
			    PROCESS__GETCAP, NULL);
L
Linus Torvalds 已提交
2198 2199
}

D
David Howells 已提交
2200 2201 2202 2203
static int selinux_capset(struct cred *new, const struct cred *old,
			  const kernel_cap_t *effective,
			  const kernel_cap_t *inheritable,
			  const kernel_cap_t *permitted)
L
Linus Torvalds 已提交
2204
{
2205 2206
	return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
			    PROCESS__SETCAP, NULL);
L
Linus Torvalds 已提交
2207 2208
}

2209 2210 2211 2212 2213 2214 2215 2216 2217 2218
/*
 * (This comment used to live with the selinux_task_setuid hook,
 * which was removed).
 *
 * Since setuid only affects the current process, and since the SELinux
 * controls are not based on the Linux identity attributes, SELinux does not
 * need to control this operation.  However, SELinux does control the use of
 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
 */

2219 2220
static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
			   int cap, int audit)
L
Linus Torvalds 已提交
2221
{
2222
	return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
L
Linus Torvalds 已提交
2223 2224 2225 2226
}

static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
{
2227
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2228 2229 2230 2231 2232 2233
	int rc = 0;

	if (!sb)
		return 0;

	switch (cmds) {
2234 2235 2236 2237 2238
	case Q_SYNC:
	case Q_QUOTAON:
	case Q_QUOTAOFF:
	case Q_SETINFO:
	case Q_SETQUOTA:
2239
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2240 2241 2242 2243
		break;
	case Q_GETFMT:
	case Q_GETINFO:
	case Q_GETQUOTA:
2244
		rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2245 2246 2247 2248
		break;
	default:
		rc = 0;  /* let the kernel handle invalid cmds */
		break;
L
Linus Torvalds 已提交
2249 2250 2251 2252 2253 2254
	}
	return rc;
}

static int selinux_quota_on(struct dentry *dentry)
{
2255 2256
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
2257
	return dentry_has_perm(cred, dentry, FILE__QUOTAON);
L
Linus Torvalds 已提交
2258 2259
}

2260
static int selinux_syslog(int type)
L
Linus Torvalds 已提交
2261 2262
{
	switch (type) {
2263 2264
	case SYSLOG_ACTION_READ_ALL:	/* Read last kernel messages */
	case SYSLOG_ACTION_SIZE_BUFFER:	/* Return size of the log buffer */
2265 2266
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2267 2268 2269 2270
	case SYSLOG_ACTION_CONSOLE_OFF:	/* Disable logging to console */
	case SYSLOG_ACTION_CONSOLE_ON:	/* Enable logging to console */
	/* Set level of messages printed to console */
	case SYSLOG_ACTION_CONSOLE_LEVEL:
2271 2272 2273
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
				    NULL);
L
Linus Torvalds 已提交
2274
	}
2275 2276 2277
	/* All other syslog types */
	return avc_has_perm(current_sid(), SECINITSID_KERNEL,
			    SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
L
Linus Torvalds 已提交
2278 2279 2280 2281 2282 2283 2284 2285 2286 2287
}

/*
 * Check that a process has enough memory to allocate a new virtual
 * mapping. 0 means there is enough memory for the allocation to
 * succeed and -ENOMEM implies there is not.
 *
 * Do not audit the selinux permission check, as this is applied to all
 * processes that allocate mappings.
 */
2288
static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
L
Linus Torvalds 已提交
2289 2290 2291
{
	int rc, cap_sys_admin = 0;

C
Casey Schaufler 已提交
2292
	rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2293
				 SECURITY_CAP_NOAUDIT, true);
L
Linus Torvalds 已提交
2294 2295 2296
	if (rc == 0)
		cap_sys_admin = 1;

C
Casey Schaufler 已提交
2297
	return cap_sys_admin;
L
Linus Torvalds 已提交
2298 2299 2300 2301
}

/* binprm security operations */

2302
static u32 ptrace_parent_sid(void)
2303 2304 2305 2306 2307
{
	u32 sid = 0;
	struct task_struct *tracer;

	rcu_read_lock();
2308
	tracer = ptrace_parent(current);
2309 2310 2311 2312 2313 2314 2315
	if (tracer)
		sid = task_sid(tracer);
	rcu_read_unlock();

	return sid;
}

2316 2317 2318 2319 2320
static int check_nnp_nosuid(const struct linux_binprm *bprm,
			    const struct task_security_struct *old_tsec,
			    const struct task_security_struct *new_tsec)
{
	int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2321
	int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2322
	int rc;
2323
	u32 av;
2324 2325 2326 2327 2328 2329 2330 2331

	if (!nnp && !nosuid)
		return 0; /* neither NNP nor nosuid */

	if (new_tsec->sid == old_tsec->sid)
		return 0; /* No change in credentials */

	/*
2332 2333 2334 2335
	 * If the policy enables the nnp_nosuid_transition policy capability,
	 * then we permit transitions under NNP or nosuid if the
	 * policy allows the corresponding permission between
	 * the old and new contexts.
2336
	 */
2337 2338
	if (selinux_policycap_nnp_nosuid_transition) {
		av = 0;
2339
		if (nnp)
2340 2341 2342 2343 2344 2345 2346
			av |= PROCESS2__NNP_TRANSITION;
		if (nosuid)
			av |= PROCESS2__NOSUID_TRANSITION;
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
				  SECCLASS_PROCESS2, av, NULL);
		if (!rc)
			return 0;
2347
	}
2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365

	/*
	 * We also permit NNP or nosuid transitions to bounded SIDs,
	 * i.e. SIDs that are guaranteed to only be allowed a subset
	 * of the permissions of the current SID.
	 */
	rc = security_bounded_transition(old_tsec->sid, new_tsec->sid);
	if (!rc)
		return 0;

	/*
	 * On failure, preserve the errno values for NNP vs nosuid.
	 * NNP:  Operation not permitted for caller.
	 * nosuid:  Permission denied to file.
	 */
	if (nnp)
		return -EPERM;
	return -EACCES;
2366 2367
}

2368
static int selinux_bprm_set_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2369
{
2370 2371
	const struct task_security_struct *old_tsec;
	struct task_security_struct *new_tsec;
L
Linus Torvalds 已提交
2372
	struct inode_security_struct *isec;
2373
	struct common_audit_data ad;
A
Al Viro 已提交
2374
	struct inode *inode = file_inode(bprm->file);
L
Linus Torvalds 已提交
2375 2376
	int rc;

2377 2378
	/* SELinux context only depends on initial program or script and not
	 * the script interpreter */
2379
	if (bprm->called_set_creds)
L
Linus Torvalds 已提交
2380 2381
		return 0;

2382 2383
	old_tsec = current_security();
	new_tsec = bprm->cred->security;
2384
	isec = inode_security(inode);
L
Linus Torvalds 已提交
2385 2386

	/* Default to the current task SID. */
2387 2388
	new_tsec->sid = old_tsec->sid;
	new_tsec->osid = old_tsec->sid;
L
Linus Torvalds 已提交
2389

2390
	/* Reset fs, key, and sock SIDs on execve. */
2391 2392 2393
	new_tsec->create_sid = 0;
	new_tsec->keycreate_sid = 0;
	new_tsec->sockcreate_sid = 0;
L
Linus Torvalds 已提交
2394

2395 2396
	if (old_tsec->exec_sid) {
		new_tsec->sid = old_tsec->exec_sid;
L
Linus Torvalds 已提交
2397
		/* Reset exec SID on execve. */
2398
		new_tsec->exec_sid = 0;
2399

2400 2401 2402 2403
		/* Fail on NNP or nosuid if not an allowed transition. */
		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
		if (rc)
			return rc;
L
Linus Torvalds 已提交
2404 2405
	} else {
		/* Check for a default transition on this program. */
2406
		rc = security_transition_sid(old_tsec->sid, isec->sid,
2407 2408
					     SECCLASS_PROCESS, NULL,
					     &new_tsec->sid);
L
Linus Torvalds 已提交
2409 2410
		if (rc)
			return rc;
2411 2412 2413 2414 2415 2416 2417 2418

		/*
		 * Fallback to old SID on NNP or nosuid if not an allowed
		 * transition.
		 */
		rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
		if (rc)
			new_tsec->sid = old_tsec->sid;
L
Linus Torvalds 已提交
2419 2420
	}

2421 2422
	ad.type = LSM_AUDIT_DATA_FILE;
	ad.u.file = bprm->file;
L
Linus Torvalds 已提交
2423

2424 2425
	if (new_tsec->sid == old_tsec->sid) {
		rc = avc_has_perm(old_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2426 2427 2428 2429 2430
				  SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
		if (rc)
			return rc;
	} else {
		/* Check permissions for the transition. */
2431
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
L
Linus Torvalds 已提交
2432 2433 2434 2435
				  SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
		if (rc)
			return rc;

2436
		rc = avc_has_perm(new_tsec->sid, isec->sid,
L
Linus Torvalds 已提交
2437 2438 2439 2440
				  SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
		if (rc)
			return rc;

2441 2442 2443 2444 2445 2446 2447 2448 2449 2450 2451
		/* Check for shared state */
		if (bprm->unsafe & LSM_UNSAFE_SHARE) {
			rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
					  SECCLASS_PROCESS, PROCESS__SHARE,
					  NULL);
			if (rc)
				return -EPERM;
		}

		/* Make sure that anyone attempting to ptrace over a task that
		 * changes its SID has the appropriate permit */
2452
		if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2453
			u32 ptsid = ptrace_parent_sid();
2454 2455 2456 2457 2458 2459 2460 2461
			if (ptsid != 0) {
				rc = avc_has_perm(ptsid, new_tsec->sid,
						  SECCLASS_PROCESS,
						  PROCESS__PTRACE, NULL);
				if (rc)
					return -EPERM;
			}
		}
L
Linus Torvalds 已提交
2462

2463 2464
		/* Clear any possibly unsafe personality bits on exec: */
		bprm->per_clear |= PER_CLEAR_ON_SETID;
2465

L
Linus Torvalds 已提交
2466 2467 2468
		/* Enable secure mode for SIDs transitions unless
		   the noatsecure permission is granted between
		   the two SIDs, i.e. ahp returns 0. */
2469 2470 2471 2472
		rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
				  SECCLASS_PROCESS, PROCESS__NOATSECURE,
				  NULL);
		bprm->secureexec |= !!rc;
L
Linus Torvalds 已提交
2473 2474
	}

2475
	return 0;
L
Linus Torvalds 已提交
2476 2477
}

A
Al Viro 已提交
2478 2479 2480 2481 2482
static int match_file(const void *p, struct file *file, unsigned fd)
{
	return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
}

L
Linus Torvalds 已提交
2483
/* Derived from fs/exec.c:flush_old_files. */
2484 2485
static inline void flush_unauthorized_files(const struct cred *cred,
					    struct files_struct *files)
L
Linus Torvalds 已提交
2486 2487
{
	struct file *file, *devnull = NULL;
2488
	struct tty_struct *tty;
2489
	int drop_tty = 0;
A
Al Viro 已提交
2490
	unsigned n;
L
Linus Torvalds 已提交
2491

2492
	tty = get_current_tty();
L
Linus Torvalds 已提交
2493
	if (tty) {
P
Peter Hurley 已提交
2494
		spin_lock(&tty->files_lock);
2495
		if (!list_empty(&tty->tty_files)) {
N
Nick Piggin 已提交
2496
			struct tty_file_private *file_priv;
2497

L
Linus Torvalds 已提交
2498
			/* Revalidate access to controlling tty.
2499 2500 2501 2502
			   Use file_path_has_perm on the tty path directly
			   rather than using file_has_perm, as this particular
			   open file may belong to another process and we are
			   only interested in the inode-based check here. */
N
Nick Piggin 已提交
2503 2504 2505
			file_priv = list_first_entry(&tty->tty_files,
						struct tty_file_private, list);
			file = file_priv->file;
2506
			if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2507
				drop_tty = 1;
L
Linus Torvalds 已提交
2508
		}
P
Peter Hurley 已提交
2509
		spin_unlock(&tty->files_lock);
A
Alan Cox 已提交
2510
		tty_kref_put(tty);
L
Linus Torvalds 已提交
2511
	}
2512 2513 2514
	/* Reset controlling tty. */
	if (drop_tty)
		no_tty();
L
Linus Torvalds 已提交
2515 2516

	/* Revalidate access to inherited open files. */
A
Al Viro 已提交
2517 2518 2519
	n = iterate_fd(files, 0, match_file, cred);
	if (!n) /* none found? */
		return;
L
Linus Torvalds 已提交
2520

A
Al Viro 已提交
2521
	devnull = dentry_open(&selinux_null, O_RDWR, cred);
A
Al Viro 已提交
2522 2523 2524 2525 2526 2527 2528
	if (IS_ERR(devnull))
		devnull = NULL;
	/* replace all the matching ones with this */
	do {
		replace_fd(n - 1, devnull, 0);
	} while ((n = iterate_fd(files, n, match_file, cred)) != 0);
	if (devnull)
A
Al Viro 已提交
2529
		fput(devnull);
L
Linus Torvalds 已提交
2530 2531
}

2532 2533 2534 2535
/*
 * Prepare a process for imminent new credential changes due to exec
 */
static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2536
{
2537 2538 2539
	struct task_security_struct *new_tsec;
	struct rlimit *rlim, *initrlim;
	int rc, i;
D
David Howells 已提交
2540

2541 2542 2543
	new_tsec = bprm->cred->security;
	if (new_tsec->sid == new_tsec->osid)
		return;
L
Linus Torvalds 已提交
2544

2545 2546
	/* Close files for which the new task SID is not authorized. */
	flush_unauthorized_files(bprm->cred, current->files);
R
Roland McGrath 已提交
2547

2548 2549
	/* Always clear parent death signal on SID transitions. */
	current->pdeath_signal = 0;
R
Roland McGrath 已提交
2550

2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563
	/* Check whether the new SID can inherit resource limits from the old
	 * SID.  If not, reset all soft limits to the lower of the current
	 * task's hard limit and the init task's soft limit.
	 *
	 * Note that the setting of hard limits (even to lower them) can be
	 * controlled by the setrlimit check.  The inclusion of the init task's
	 * soft limit into the computation is to avoid resetting soft limits
	 * higher than the default soft limit for cases where the default is
	 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
	 */
	rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
			  PROCESS__RLIMITINH, NULL);
	if (rc) {
2564 2565
		/* protect against do_prlimit() */
		task_lock(current);
2566 2567 2568 2569
		for (i = 0; i < RLIM_NLIMITS; i++) {
			rlim = current->signal->rlim + i;
			initrlim = init_task.signal->rlim + i;
			rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
L
Linus Torvalds 已提交
2570
		}
2571
		task_unlock(current);
2572 2573
		if (IS_ENABLED(CONFIG_POSIX_TIMERS))
			update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
L
Linus Torvalds 已提交
2574 2575 2576 2577
	}
}

/*
2578 2579
 * Clean up the process immediately after the installation of new credentials
 * due to exec
L
Linus Torvalds 已提交
2580
 */
2581
static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
L
Linus Torvalds 已提交
2582
{
2583
	const struct task_security_struct *tsec = current_security();
L
Linus Torvalds 已提交
2584
	struct itimerval itimer;
2585
	u32 osid, sid;
L
Linus Torvalds 已提交
2586 2587
	int rc, i;

2588 2589 2590 2591
	osid = tsec->osid;
	sid = tsec->sid;

	if (sid == osid)
L
Linus Torvalds 已提交
2592 2593
		return;

2594 2595 2596 2597 2598 2599 2600 2601
	/* Check whether the new SID can inherit signal state from the old SID.
	 * If not, clear itimers to avoid subsequent signal generation and
	 * flush and unblock signals.
	 *
	 * This must occur _after_ the task SID has been updated so that any
	 * kill done after the flush will be checked against the new SID.
	 */
	rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
L
Linus Torvalds 已提交
2602
	if (rc) {
2603 2604 2605 2606 2607
		if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
			memset(&itimer, 0, sizeof itimer);
			for (i = 0; i < 3; i++)
				do_setitimer(i, &itimer, NULL);
		}
L
Linus Torvalds 已提交
2608
		spin_lock_irq(&current->sighand->siglock);
2609 2610 2611
		if (!fatal_signal_pending(current)) {
			flush_sigqueue(&current->pending);
			flush_sigqueue(&current->signal->shared_pending);
2612 2613
			flush_signal_handlers(current, 1);
			sigemptyset(&current->blocked);
2614
			recalc_sigpending();
2615
		}
L
Linus Torvalds 已提交
2616 2617 2618
		spin_unlock_irq(&current->sighand->siglock);
	}

2619 2620
	/* Wake up the parent if it is waiting so that it can recheck
	 * wait permission to the new task SID. */
2621
	read_lock(&tasklist_lock);
2622
	__wake_up_parent(current, current->real_parent);
2623
	read_unlock(&tasklist_lock);
L
Linus Torvalds 已提交
2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647
}

/* superblock security operations */

static int selinux_sb_alloc_security(struct super_block *sb)
{
	return superblock_alloc_security(sb);
}

static void selinux_sb_free_security(struct super_block *sb)
{
	superblock_free_security(sb);
}

static inline int match_prefix(char *prefix, int plen, char *option, int olen)
{
	if (plen > olen)
		return 0;

	return !memcmp(prefix, option, plen);
}

static inline int selinux_option(char *option, int len)
{
2648 2649 2650
	return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
		match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
		match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2651 2652
		match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
		match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
L
Linus Torvalds 已提交
2653 2654 2655 2656 2657 2658 2659
}

static inline void take_option(char **to, char *from, int *first, int len)
{
	if (!*first) {
		**to = ',';
		*to += 1;
2660
	} else
L
Linus Torvalds 已提交
2661 2662 2663 2664 2665
		*first = 0;
	memcpy(*to, from, len);
	*to += len;
}

2666 2667
static inline void take_selinux_option(char **to, char *from, int *first,
				       int len)
2668 2669 2670 2671 2672 2673
{
	int current_size = 0;

	if (!*first) {
		**to = '|';
		*to += 1;
2674
	} else
2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686
		*first = 0;

	while (current_size < len) {
		if (*from != '"') {
			**to = *from;
			*to += 1;
		}
		from += 1;
		current_size += 1;
	}
}

2687
static int selinux_sb_copy_data(char *orig, char *copy)
L
Linus Torvalds 已提交
2688 2689 2690 2691
{
	int fnosec, fsec, rc = 0;
	char *in_save, *in_curr, *in_end;
	char *sec_curr, *nosec_save, *nosec;
2692
	int open_quote = 0;
L
Linus Torvalds 已提交
2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707

	in_curr = orig;
	sec_curr = copy;

	nosec = (char *)get_zeroed_page(GFP_KERNEL);
	if (!nosec) {
		rc = -ENOMEM;
		goto out;
	}

	nosec_save = nosec;
	fnosec = fsec = 1;
	in_save = in_end = orig;

	do {
2708 2709 2710 2711
		if (*in_end == '"')
			open_quote = !open_quote;
		if ((*in_end == ',' && open_quote == 0) ||
				*in_end == '\0') {
L
Linus Torvalds 已提交
2712 2713 2714
			int len = in_end - in_curr;

			if (selinux_option(in_curr, len))
2715
				take_selinux_option(&sec_curr, in_curr, &fsec, len);
L
Linus Torvalds 已提交
2716 2717 2718 2719 2720 2721 2722
			else
				take_option(&nosec, in_curr, &fnosec, len);

			in_curr = in_end + 1;
		}
	} while (*in_end++);

2723
	strcpy(in_save, nosec_save);
2724
	free_page((unsigned long)nosec_save);
L
Linus Torvalds 已提交
2725 2726 2727 2728
out:
	return rc;
}

2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762
static int selinux_sb_remount(struct super_block *sb, void *data)
{
	int rc, i, *flags;
	struct security_mnt_opts opts;
	char *secdata, **mount_options;
	struct superblock_security_struct *sbsec = sb->s_security;

	if (!(sbsec->flags & SE_SBINITIALIZED))
		return 0;

	if (!data)
		return 0;

	if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
		return 0;

	security_init_mnt_opts(&opts);
	secdata = alloc_secdata();
	if (!secdata)
		return -ENOMEM;
	rc = selinux_sb_copy_data(data, secdata);
	if (rc)
		goto out_free_secdata;

	rc = selinux_parse_opts_str(secdata, &opts);
	if (rc)
		goto out_free_secdata;

	mount_options = opts.mnt_opts;
	flags = opts.mnt_opts_flags;

	for (i = 0; i < opts.num_mnt_opts; i++) {
		u32 sid;

2763
		if (flags[i] == SBLABEL_MNT)
2764
			continue;
2765
		rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
2766
		if (rc) {
2767
			printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2768 2769
			       "(%s) failed for (dev %s, type %s) errno=%d\n",
			       mount_options[i], sb->s_id, sb->s_type->name, rc);
2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783
			goto out_free_opts;
		}
		rc = -EINVAL;
		switch (flags[i]) {
		case FSCONTEXT_MNT:
			if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
				goto out_bad_option;
			break;
		case CONTEXT_MNT:
			if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
				goto out_bad_option;
			break;
		case ROOTCONTEXT_MNT: {
			struct inode_security_struct *root_isec;
2784
			root_isec = backing_inode_security(sb->s_root);
2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806

			if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
				goto out_bad_option;
			break;
		}
		case DEFCONTEXT_MNT:
			if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
				goto out_bad_option;
			break;
		default:
			goto out_free_opts;
		}
	}

	rc = 0;
out_free_opts:
	security_free_mnt_opts(&opts);
out_free_secdata:
	free_secdata(secdata);
	return rc;
out_bad_option:
	printk(KERN_WARNING "SELinux: unable to change security options "
2807 2808
	       "during remount (dev %s, type=%s)\n", sb->s_id,
	       sb->s_type->name);
2809 2810 2811
	goto out_free_opts;
}

2812
static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
L
Linus Torvalds 已提交
2813
{
2814
	const struct cred *cred = current_cred();
2815
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2816 2817 2818 2819 2820 2821
	int rc;

	rc = superblock_doinit(sb, data);
	if (rc)
		return rc;

2822 2823 2824 2825
	/* Allow all mounts performed by the kernel */
	if (flags & MS_KERNMOUNT)
		return 0;

2826
	ad.type = LSM_AUDIT_DATA_DENTRY;
2827
	ad.u.dentry = sb->s_root;
2828
	return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
L
Linus Torvalds 已提交
2829 2830
}

2831
static int selinux_sb_statfs(struct dentry *dentry)
L
Linus Torvalds 已提交
2832
{
2833
	const struct cred *cred = current_cred();
2834
	struct common_audit_data ad;
L
Linus Torvalds 已提交
2835

2836
	ad.type = LSM_AUDIT_DATA_DENTRY;
2837
	ad.u.dentry = dentry->d_sb->s_root;
2838
	return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
L
Linus Torvalds 已提交
2839 2840
}

A
Al Viro 已提交
2841
static int selinux_mount(const char *dev_name,
A
Al Viro 已提交
2842
			 const struct path *path,
A
Al Viro 已提交
2843
			 const char *type,
2844 2845
			 unsigned long flags,
			 void *data)
L
Linus Torvalds 已提交
2846
{
2847
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2848 2849

	if (flags & MS_REMOUNT)
2850
		return superblock_has_perm(cred, path->dentry->d_sb,
2851
					   FILESYSTEM__REMOUNT, NULL);
L
Linus Torvalds 已提交
2852
	else
E
Eric Paris 已提交
2853
		return path_has_perm(cred, path, FILE__MOUNTON);
L
Linus Torvalds 已提交
2854 2855 2856 2857
}

static int selinux_umount(struct vfsmount *mnt, int flags)
{
2858
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
2859

2860
	return superblock_has_perm(cred, mnt->mnt_sb,
2861
				   FILESYSTEM__UNMOUNT, NULL);
L
Linus Torvalds 已提交
2862 2863 2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875
}

/* inode security operations */

static int selinux_inode_alloc_security(struct inode *inode)
{
	return inode_alloc_security(inode);
}

static void selinux_inode_free_security(struct inode *inode)
{
	inode_free_security(inode);
}

2876
static int selinux_dentry_init_security(struct dentry *dentry, int mode,
A
Al Viro 已提交
2877
					const struct qstr *name, void **ctx,
2878 2879 2880 2881 2882
					u32 *ctxlen)
{
	u32 newsid;
	int rc;

2883 2884
	rc = selinux_determine_inode_label(current_security(),
					   d_inode(dentry->d_parent), name,
2885 2886 2887 2888
					   inode_mode_to_security_class(mode),
					   &newsid);
	if (rc)
		return rc;
2889 2890 2891 2892

	return security_sid_to_context(newsid, (char **)ctx, ctxlen);
}

2893 2894 2895 2896 2897 2898 2899 2900 2901 2902 2903 2904 2905 2906 2907 2908 2909 2910 2911 2912 2913
static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
					  struct qstr *name,
					  const struct cred *old,
					  struct cred *new)
{
	u32 newsid;
	int rc;
	struct task_security_struct *tsec;

	rc = selinux_determine_inode_label(old->security,
					   d_inode(dentry->d_parent), name,
					   inode_mode_to_security_class(mode),
					   &newsid);
	if (rc)
		return rc;

	tsec = new->security;
	tsec->create_sid = newsid;
	return 0;
}

2914
static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2915 2916
				       const struct qstr *qstr,
				       const char **name,
2917
				       void **value, size_t *len)
2918
{
2919
	const struct task_security_struct *tsec = current_security();
2920
	struct superblock_security_struct *sbsec;
2921
	u32 newsid, clen;
2922
	int rc;
2923
	char *context;
2924 2925 2926

	sbsec = dir->i_sb->s_security;

2927 2928
	newsid = tsec->create_sid;

2929
	rc = selinux_determine_inode_label(current_security(),
2930 2931 2932 2933 2934
		dir, qstr,
		inode_mode_to_security_class(inode->i_mode),
		&newsid);
	if (rc)
		return rc;
2935

2936
	/* Possibly defer initialization to selinux_complete_init. */
2937
	if (sbsec->flags & SE_SBINITIALIZED) {
2938 2939 2940
		struct inode_security_struct *isec = inode->i_security;
		isec->sclass = inode_mode_to_security_class(inode->i_mode);
		isec->sid = newsid;
2941
		isec->initialized = LABEL_INITIALIZED;
2942
	}
2943

2944
	if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2945 2946
		return -EOPNOTSUPP;

2947 2948
	if (name)
		*name = XATTR_SELINUX_SUFFIX;
2949

2950
	if (value && len) {
2951
		rc = security_sid_to_context_force(newsid, &context, &clen);
2952
		if (rc)
2953 2954 2955
			return rc;
		*value = context;
		*len = clen;
2956 2957 2958 2959 2960
	}

	return 0;
}

A
Al Viro 已提交
2961
static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
L
Linus Torvalds 已提交
2962 2963 2964 2965 2966 2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978 2979 2980
{
	return may_create(dir, dentry, SECCLASS_FILE);
}

static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
{
	return may_link(dir, old_dentry, MAY_LINK);
}

static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
{
	return may_link(dir, dentry, MAY_UNLINK);
}

static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
{
	return may_create(dir, dentry, SECCLASS_LNK_FILE);
}

2981
static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
L
Linus Torvalds 已提交
2982 2983 2984 2985 2986 2987 2988 2989 2990
{
	return may_create(dir, dentry, SECCLASS_DIR);
}

static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
{
	return may_link(dir, dentry, MAY_RMDIR);
}

A
Al Viro 已提交
2991
static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
L
Linus Torvalds 已提交
2992 2993 2994 2995 2996
{
	return may_create(dir, dentry, inode_mode_to_security_class(mode));
}

static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2997
				struct inode *new_inode, struct dentry *new_dentry)
L
Linus Torvalds 已提交
2998 2999 3000 3001 3002 3003
{
	return may_rename(old_inode, old_dentry, new_inode, new_dentry);
}

static int selinux_inode_readlink(struct dentry *dentry)
{
3004 3005
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3006
	return dentry_has_perm(cred, dentry, FILE__READ);
L
Linus Torvalds 已提交
3007 3008
}

3009 3010
static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
				     bool rcu)
L
Linus Torvalds 已提交
3011
{
3012
	const struct cred *cred = current_cred();
3013 3014 3015
	struct common_audit_data ad;
	struct inode_security_struct *isec;
	u32 sid;
L
Linus Torvalds 已提交
3016

3017 3018 3019 3020 3021
	validate_creds(cred);

	ad.type = LSM_AUDIT_DATA_DENTRY;
	ad.u.dentry = dentry;
	sid = cred_sid(cred);
3022 3023 3024
	isec = inode_security_rcu(inode, rcu);
	if (IS_ERR(isec))
		return PTR_ERR(isec);
3025 3026 3027

	return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad,
				  rcu ? MAY_NOT_BLOCK : 0);
L
Linus Torvalds 已提交
3028 3029
}

3030 3031
static noinline int audit_inode_permission(struct inode *inode,
					   u32 perms, u32 audited, u32 denied,
3032
					   int result,
3033
					   unsigned flags)
L
Linus Torvalds 已提交
3034
{
3035
	struct common_audit_data ad;
3036 3037 3038
	struct inode_security_struct *isec = inode->i_security;
	int rc;

3039
	ad.type = LSM_AUDIT_DATA_INODE;
3040 3041 3042
	ad.u.inode = inode;

	rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3043
			    audited, denied, result, &ad, flags);
3044 3045 3046 3047 3048
	if (rc)
		return rc;
	return 0;
}

3049
static int selinux_inode_permission(struct inode *inode, int mask)
L
Linus Torvalds 已提交
3050
{
3051
	const struct cred *cred = current_cred();
3052 3053
	u32 perms;
	bool from_access;
3054
	unsigned flags = mask & MAY_NOT_BLOCK;
3055 3056 3057 3058 3059
	struct inode_security_struct *isec;
	u32 sid;
	struct av_decision avd;
	int rc, rc2;
	u32 audited, denied;
L
Linus Torvalds 已提交
3060

3061
	from_access = mask & MAY_ACCESS;
3062 3063
	mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);

3064 3065
	/* No permission to check.  Existence test. */
	if (!mask)
L
Linus Torvalds 已提交
3066 3067
		return 0;

3068
	validate_creds(cred);
3069

3070 3071
	if (unlikely(IS_PRIVATE(inode)))
		return 0;
3072 3073 3074

	perms = file_mask_to_av(inode->i_mode, mask);

3075
	sid = cred_sid(cred);
3076 3077 3078
	isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
	if (IS_ERR(isec))
		return PTR_ERR(isec);
3079 3080 3081 3082 3083 3084 3085 3086

	rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
	audited = avc_audit_required(perms, &avd, rc,
				     from_access ? FILE__AUDIT_ACCESS : 0,
				     &denied);
	if (likely(!audited))
		return rc;

3087
	rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3088 3089 3090
	if (rc2)
		return rc2;
	return rc;
L
Linus Torvalds 已提交
3091 3092 3093 3094
}

static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
{
3095
	const struct cred *cred = current_cred();
3096
	struct inode *inode = d_backing_inode(dentry);
3097
	unsigned int ia_valid = iattr->ia_valid;
3098
	__u32 av = FILE__WRITE;
L
Linus Torvalds 已提交
3099

3100 3101 3102 3103 3104 3105 3106
	/* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
	if (ia_valid & ATTR_FORCE) {
		ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
			      ATTR_FORCE);
		if (!ia_valid)
			return 0;
	}
L
Linus Torvalds 已提交
3107

3108 3109
	if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
			ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
E
Eric Paris 已提交
3110
		return dentry_has_perm(cred, dentry, FILE__SETATTR);
L
Linus Torvalds 已提交
3111

3112 3113 3114 3115
	if (selinux_policycap_openperm &&
	    inode->i_sb->s_magic != SOCKFS_MAGIC &&
	    (ia_valid & ATTR_SIZE) &&
	    !(ia_valid & ATTR_FILE))
3116 3117 3118
		av |= FILE__OPEN;

	return dentry_has_perm(cred, dentry, av);
L
Linus Torvalds 已提交
3119 3120
}

3121
static int selinux_inode_getattr(const struct path *path)
L
Linus Torvalds 已提交
3122
{
3123
	return path_has_perm(current_cred(), path, FILE__GETATTR);
L
Linus Torvalds 已提交
3124 3125
}

3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137
static bool has_cap_mac_admin(bool audit)
{
	const struct cred *cred = current_cred();
	int cap_audit = audit ? SECURITY_CAP_AUDIT : SECURITY_CAP_NOAUDIT;

	if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, cap_audit))
		return false;
	if (cred_has_capability(cred, CAP_MAC_ADMIN, cap_audit, true))
		return false;
	return true;
}

3138 3139
static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
				  const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
3140
{
3141
	struct inode *inode = d_backing_inode(dentry);
3142
	struct inode_security_struct *isec;
L
Linus Torvalds 已提交
3143
	struct superblock_security_struct *sbsec;
3144
	struct common_audit_data ad;
3145
	u32 newsid, sid = current_sid();
L
Linus Torvalds 已提交
3146 3147
	int rc = 0;

3148 3149 3150 3151 3152 3153 3154 3155 3156
	if (strcmp(name, XATTR_NAME_SELINUX)) {
		rc = cap_inode_setxattr(dentry, name, value, size, flags);
		if (rc)
			return rc;

		/* Not an attribute we recognize, so just check the
		   ordinary setattr permission. */
		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
	}
L
Linus Torvalds 已提交
3157 3158

	sbsec = inode->i_sb->s_security;
3159
	if (!(sbsec->flags & SBLABEL_MNT))
L
Linus Torvalds 已提交
3160 3161
		return -EOPNOTSUPP;

3162
	if (!inode_owner_or_capable(inode))
L
Linus Torvalds 已提交
3163 3164
		return -EPERM;

3165
	ad.type = LSM_AUDIT_DATA_DENTRY;
3166
	ad.u.dentry = dentry;
L
Linus Torvalds 已提交
3167

3168
	isec = backing_inode_security(dentry);
3169
	rc = avc_has_perm(sid, isec->sid, isec->sclass,
L
Linus Torvalds 已提交
3170 3171 3172 3173
			  FILE__RELABELFROM, &ad);
	if (rc)
		return rc;

3174
	rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3175
	if (rc == -EINVAL) {
3176
		if (!has_cap_mac_admin(true)) {
3177 3178 3179 3180 3181 3182
			struct audit_buffer *ab;
			size_t audit_size;
			const char *str;

			/* We strip a nul only if it is at the end, otherwise the
			 * context contains a nul and we should audit that */
3183 3184 3185 3186 3187 3188 3189 3190 3191 3192
			if (value) {
				str = value;
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
			} else {
				str = "";
				audit_size = 0;
			}
3193 3194 3195 3196 3197
			ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
			audit_log_format(ab, "op=setxattr invalid_context=");
			audit_log_n_untrustedstring(ab, value, audit_size);
			audit_log_end(ab);

3198
			return rc;
3199
		}
3200 3201
		rc = security_context_to_sid_force(value, size, &newsid);
	}
L
Linus Torvalds 已提交
3202 3203 3204
	if (rc)
		return rc;

3205
	rc = avc_has_perm(sid, newsid, isec->sclass,
L
Linus Torvalds 已提交
3206 3207 3208 3209
			  FILE__RELABELTO, &ad);
	if (rc)
		return rc;

3210
	rc = security_validate_transition(isec->sid, newsid, sid,
3211
					  isec->sclass);
L
Linus Torvalds 已提交
3212 3213 3214 3215 3216 3217 3218 3219 3220 3221
	if (rc)
		return rc;

	return avc_has_perm(newsid,
			    sbsec->sid,
			    SECCLASS_FILESYSTEM,
			    FILESYSTEM__ASSOCIATE,
			    &ad);
}

3222
static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3223
					const void *value, size_t size,
3224
					int flags)
L
Linus Torvalds 已提交
3225
{
3226
	struct inode *inode = d_backing_inode(dentry);
3227
	struct inode_security_struct *isec;
L
Linus Torvalds 已提交
3228 3229 3230 3231 3232 3233 3234 3235
	u32 newsid;
	int rc;

	if (strcmp(name, XATTR_NAME_SELINUX)) {
		/* Not an attribute we recognize, so nothing to do. */
		return;
	}

3236
	rc = security_context_to_sid_force(value, size, &newsid);
L
Linus Torvalds 已提交
3237
	if (rc) {
3238 3239 3240
		printk(KERN_ERR "SELinux:  unable to map context to SID"
		       "for (%s, %lu), rc=%d\n",
		       inode->i_sb->s_id, inode->i_ino, -rc);
L
Linus Torvalds 已提交
3241 3242 3243
		return;
	}

3244
	isec = backing_inode_security(dentry);
3245
	spin_lock(&isec->lock);
3246
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3247
	isec->sid = newsid;
3248
	isec->initialized = LABEL_INITIALIZED;
3249
	spin_unlock(&isec->lock);
3250

L
Linus Torvalds 已提交
3251 3252 3253
	return;
}

3254
static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
3255
{
3256 3257
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3258
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3259 3260
}

3261
static int selinux_inode_listxattr(struct dentry *dentry)
L
Linus Torvalds 已提交
3262
{
3263 3264
	const struct cred *cred = current_cred();

E
Eric Paris 已提交
3265
	return dentry_has_perm(cred, dentry, FILE__GETATTR);
L
Linus Torvalds 已提交
3266 3267
}

3268
static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
L
Linus Torvalds 已提交
3269
{
3270 3271 3272 3273 3274 3275 3276 3277 3278
	if (strcmp(name, XATTR_NAME_SELINUX)) {
		int rc = cap_inode_removexattr(dentry, name);
		if (rc)
			return rc;

		/* Not an attribute we recognize, so just check the
		   ordinary setattr permission. */
		return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
	}
L
Linus Torvalds 已提交
3279 3280 3281 3282 3283 3284

	/* No one is allowed to remove a SELinux security label.
	   You can change the label, but all data must be labeled. */
	return -EACCES;
}

3285
/*
3286
 * Copy the inode security context value to the user.
3287 3288 3289
 *
 * Permission check is handled by selinux_inode_getxattr hook.
 */
3290
static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
L
Linus Torvalds 已提交
3291
{
3292 3293 3294
	u32 size;
	int error;
	char *context = NULL;
3295
	struct inode_security_struct *isec;
3296

3297 3298
	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;
3299

3300 3301 3302 3303 3304 3305 3306 3307 3308
	/*
	 * If the caller has CAP_MAC_ADMIN, then get the raw context
	 * value even if it is not defined by current policy; otherwise,
	 * use the in-core value under current policy.
	 * Use the non-auditing forms of the permission checks since
	 * getxattr may be called by unprivileged processes commonly
	 * and lack of permission just means that we fall back to the
	 * in-core context value, not a denial.
	 */
3309
	isec = inode_security(inode);
3310
	if (has_cap_mac_admin(false))
3311 3312 3313 3314
		error = security_sid_to_context_force(isec->sid, &context,
						      &size);
	else
		error = security_sid_to_context(isec->sid, &context, &size);
3315 3316 3317 3318 3319 3320 3321 3322 3323 3324
	if (error)
		return error;
	error = size;
	if (alloc) {
		*buffer = context;
		goto out_nofree;
	}
	kfree(context);
out_nofree:
	return error;
L
Linus Torvalds 已提交
3325 3326 3327
}

static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3328
				     const void *value, size_t size, int flags)
L
Linus Torvalds 已提交
3329
{
3330
	struct inode_security_struct *isec = inode_security_novalidate(inode);
L
Linus Torvalds 已提交
3331 3332 3333 3334 3335 3336 3337 3338 3339
	u32 newsid;
	int rc;

	if (strcmp(name, XATTR_SELINUX_SUFFIX))
		return -EOPNOTSUPP;

	if (!value || !size)
		return -EACCES;

3340
	rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
L
Linus Torvalds 已提交
3341 3342 3343
	if (rc)
		return rc;

3344
	spin_lock(&isec->lock);
3345
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
L
Linus Torvalds 已提交
3346
	isec->sid = newsid;
3347
	isec->initialized = LABEL_INITIALIZED;
3348
	spin_unlock(&isec->lock);
L
Linus Torvalds 已提交
3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359
	return 0;
}

static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
{
	const int len = sizeof(XATTR_NAME_SELINUX);
	if (buffer && len <= buffer_size)
		memcpy(buffer, XATTR_NAME_SELINUX, len);
	return len;
}

3360
static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3361
{
3362
	struct inode_security_struct *isec = inode_security_novalidate(inode);
3363 3364 3365
	*secid = isec->sid;
}

3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385
static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
{
	u32 sid;
	struct task_security_struct *tsec;
	struct cred *new_creds = *new;

	if (new_creds == NULL) {
		new_creds = prepare_creds();
		if (!new_creds)
			return -ENOMEM;
	}

	tsec = new_creds->security;
	/* Get label from overlay inode and set it in create_sid */
	selinux_inode_getsecid(d_inode(src), &sid);
	tsec->create_sid = sid;
	*new = new_creds;
	return 0;
}

3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400
static int selinux_inode_copy_up_xattr(const char *name)
{
	/* The copy_up hook above sets the initial context on an inode, but we
	 * don't then want to overwrite it by blindly copying all the lower
	 * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
	 */
	if (strcmp(name, XATTR_NAME_SELINUX) == 0)
		return 1; /* Discard */
	/*
	 * Any other attribute apart from SELINUX is not claimed, supported
	 * by selinux.
	 */
	return -EOPNOTSUPP;
}

L
Linus Torvalds 已提交
3401 3402
/* file security operations */

3403
static int selinux_revalidate_file_permission(struct file *file, int mask)
L
Linus Torvalds 已提交
3404
{
3405
	const struct cred *cred = current_cred();
A
Al Viro 已提交
3406
	struct inode *inode = file_inode(file);
L
Linus Torvalds 已提交
3407 3408 3409 3410 3411

	/* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
	if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
		mask |= MAY_APPEND;

3412 3413
	return file_has_perm(cred, file,
			     file_mask_to_av(inode->i_mode, mask));
L
Linus Torvalds 已提交
3414 3415
}

3416 3417
static int selinux_file_permission(struct file *file, int mask)
{
A
Al Viro 已提交
3418
	struct inode *inode = file_inode(file);
3419
	struct file_security_struct *fsec = file->f_security;
3420
	struct inode_security_struct *isec;
3421 3422
	u32 sid = current_sid();

3423
	if (!mask)
3424 3425 3426
		/* No permission to check.  Existence test. */
		return 0;

3427
	isec = inode_security(inode);
3428 3429
	if (sid == fsec->sid && fsec->isid == isec->sid &&
	    fsec->pseqno == avc_policy_seqno())
3430
		/* No change since file_open check. */
3431 3432
		return 0;

3433 3434 3435
	return selinux_revalidate_file_permission(file, mask);
}

L
Linus Torvalds 已提交
3436 3437 3438 3439 3440 3441 3442 3443 3444 3445
static int selinux_file_alloc_security(struct file *file)
{
	return file_alloc_security(file);
}

static void selinux_file_free_security(struct file *file)
{
	file_free_security(file);
}

3446 3447 3448 3449
/*
 * Check whether a task has the ioctl permission and cmd
 * operation to an inode.
 */
3450
static int ioctl_has_perm(const struct cred *cred, struct file *file,
3451 3452 3453 3454 3455
		u32 requested, u16 cmd)
{
	struct common_audit_data ad;
	struct file_security_struct *fsec = file->f_security;
	struct inode *inode = file_inode(file);
3456
	struct inode_security_struct *isec;
3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472 3473 3474 3475 3476 3477 3478 3479
	struct lsm_ioctlop_audit ioctl;
	u32 ssid = cred_sid(cred);
	int rc;
	u8 driver = cmd >> 8;
	u8 xperm = cmd & 0xff;

	ad.type = LSM_AUDIT_DATA_IOCTL_OP;
	ad.u.op = &ioctl;
	ad.u.op->cmd = cmd;
	ad.u.op->path = file->f_path;

	if (ssid != fsec->sid) {
		rc = avc_has_perm(ssid, fsec->sid,
				SECCLASS_FD,
				FD__USE,
				&ad);
		if (rc)
			goto out;
	}

	if (unlikely(IS_PRIVATE(inode)))
		return 0;

3480
	isec = inode_security(inode);
3481 3482 3483 3484 3485 3486
	rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
			requested, driver, xperm, &ad);
out:
	return rc;
}

L
Linus Torvalds 已提交
3487 3488 3489
static int selinux_file_ioctl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3490
	const struct cred *cred = current_cred();
3491
	int error = 0;
L
Linus Torvalds 已提交
3492

3493 3494 3495 3496 3497 3498 3499
	switch (cmd) {
	case FIONREAD:
	/* fall through */
	case FIBMAP:
	/* fall through */
	case FIGETBSZ:
	/* fall through */
3500
	case FS_IOC_GETFLAGS:
3501
	/* fall through */
3502
	case FS_IOC_GETVERSION:
3503 3504
		error = file_has_perm(cred, file, FILE__GETATTR);
		break;
L
Linus Torvalds 已提交
3505

3506
	case FS_IOC_SETFLAGS:
3507
	/* fall through */
3508
	case FS_IOC_SETVERSION:
3509 3510 3511 3512 3513 3514 3515 3516 3517
		error = file_has_perm(cred, file, FILE__SETATTR);
		break;

	/* sys_ioctl() checks */
	case FIONBIO:
	/* fall through */
	case FIOASYNC:
		error = file_has_perm(cred, file, 0);
		break;
L
Linus Torvalds 已提交
3518

3519 3520
	case KDSKBENT:
	case KDSKBSENT:
3521
		error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3522
					    SECURITY_CAP_AUDIT, true);
3523 3524 3525 3526 3527 3528
		break;

	/* default case assumes that the command will go
	 * to the file's ioctl() function.
	 */
	default:
3529
		error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3530 3531
	}
	return error;
L
Linus Torvalds 已提交
3532 3533
}

3534 3535
static int default_noexec;

L
Linus Torvalds 已提交
3536 3537
static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
{
3538
	const struct cred *cred = current_cred();
3539
	u32 sid = cred_sid(cred);
D
David Howells 已提交
3540
	int rc = 0;
3541

3542
	if (default_noexec &&
3543 3544
	    (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
				   (!shared && (prot & PROT_WRITE)))) {
L
Linus Torvalds 已提交
3545 3546 3547 3548 3549
		/*
		 * We are making executable an anonymous mapping or a
		 * private file mapping that will also be writable.
		 * This has an additional check.
		 */
3550 3551
		rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
				  PROCESS__EXECMEM, NULL);
L
Linus Torvalds 已提交
3552
		if (rc)
D
David Howells 已提交
3553
			goto error;
L
Linus Torvalds 已提交
3554 3555 3556 3557 3558 3559 3560 3561 3562 3563 3564 3565 3566
	}

	if (file) {
		/* read access is always possible with a mapping */
		u32 av = FILE__READ;

		/* write access only matters if the mapping is shared */
		if (shared && (prot & PROT_WRITE))
			av |= FILE__WRITE;

		if (prot & PROT_EXEC)
			av |= FILE__EXECUTE;

3567
		return file_has_perm(cred, file, av);
L
Linus Torvalds 已提交
3568
	}
D
David Howells 已提交
3569 3570 3571

error:
	return rc;
L
Linus Torvalds 已提交
3572 3573
}

3574
static int selinux_mmap_addr(unsigned long addr)
L
Linus Torvalds 已提交
3575
{
C
Casey Schaufler 已提交
3576
	int rc = 0;
L
Linus Torvalds 已提交
3577

3578
	if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3579
		u32 sid = current_sid();
3580 3581
		rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
				  MEMPROTECT__MMAP_ZERO, NULL);
3582 3583
	}

3584
	return rc;
3585
}
L
Linus Torvalds 已提交
3586

3587 3588 3589
static int selinux_mmap_file(struct file *file, unsigned long reqprot,
			     unsigned long prot, unsigned long flags)
{
3590 3591 3592 3593 3594 3595 3596 3597 3598 3599 3600 3601
	struct common_audit_data ad;
	int rc;

	if (file) {
		ad.type = LSM_AUDIT_DATA_FILE;
		ad.u.file = file;
		rc = inode_has_perm(current_cred(), file_inode(file),
				    FILE__MAP, &ad);
		if (rc)
			return rc;
	}

L
Linus Torvalds 已提交
3602 3603 3604 3605 3606 3607 3608 3609 3610 3611 3612
	if (selinux_checkreqprot)
		prot = reqprot;

	return file_map_prot_check(file, prot,
				   (flags & MAP_TYPE) == MAP_SHARED);
}

static int selinux_file_mprotect(struct vm_area_struct *vma,
				 unsigned long reqprot,
				 unsigned long prot)
{
3613
	const struct cred *cred = current_cred();
3614
	u32 sid = cred_sid(cred);
L
Linus Torvalds 已提交
3615 3616 3617 3618

	if (selinux_checkreqprot)
		prot = reqprot;

3619 3620
	if (default_noexec &&
	    (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3621
		int rc = 0;
3622 3623
		if (vma->vm_start >= vma->vm_mm->start_brk &&
		    vma->vm_end <= vma->vm_mm->brk) {
3624 3625
			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
					  PROCESS__EXECHEAP, NULL);
3626
		} else if (!vma->vm_file &&
3627 3628
			   ((vma->vm_start <= vma->vm_mm->start_stack &&
			     vma->vm_end >= vma->vm_mm->start_stack) ||
3629
			    vma_is_stack_for_current(vma))) {
3630 3631
			rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
					  PROCESS__EXECSTACK, NULL);
3632 3633 3634 3635 3636 3637 3638 3639
		} else if (vma->vm_file && vma->anon_vma) {
			/*
			 * We are making executable a file mapping that has
			 * had some COW done. Since pages might have been
			 * written, check ability to execute the possibly
			 * modified content.  This typically should only
			 * occur for text relocations.
			 */
D
David Howells 已提交
3640
			rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3641
		}
3642 3643 3644
		if (rc)
			return rc;
	}
L
Linus Torvalds 已提交
3645 3646 3647 3648 3649 3650

	return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
}

static int selinux_file_lock(struct file *file, unsigned int cmd)
{
3651 3652 3653
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, FILE__LOCK);
L
Linus Torvalds 已提交
3654 3655 3656 3657 3658
}

static int selinux_file_fcntl(struct file *file, unsigned int cmd,
			      unsigned long arg)
{
3659
	const struct cred *cred = current_cred();
L
Linus Torvalds 已提交
3660 3661 3662
	int err = 0;

	switch (cmd) {
3663 3664
	case F_SETFL:
		if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3665
			err = file_has_perm(cred, file, FILE__WRITE);
L
Linus Torvalds 已提交
3666
			break;
3667 3668 3669 3670 3671 3672 3673
		}
		/* fall through */
	case F_SETOWN:
	case F_SETSIG:
	case F_GETFL:
	case F_GETOWN:
	case F_GETSIG:
3674
	case F_GETOWNER_UIDS:
3675
		/* Just check FD__USE permission */
3676
		err = file_has_perm(cred, file, 0);
3677 3678 3679 3680
		break;
	case F_GETLK:
	case F_SETLK:
	case F_SETLKW:
3681 3682 3683
	case F_OFD_GETLK:
	case F_OFD_SETLK:
	case F_OFD_SETLKW:
L
Linus Torvalds 已提交
3684
#if BITS_PER_LONG == 32
3685 3686 3687
	case F_GETLK64:
	case F_SETLK64:
	case F_SETLKW64:
L
Linus Torvalds 已提交
3688
#endif
3689
		err = file_has_perm(cred, file, FILE__LOCK);
3690
		break;
L
Linus Torvalds 已提交
3691 3692 3693 3694 3695
	}

	return err;
}

3696
static void selinux_file_set_fowner(struct file *file)
L
Linus Torvalds 已提交
3697 3698 3699 3700
{
	struct file_security_struct *fsec;

	fsec = file->f_security;
3701
	fsec->fown_sid = current_sid();
L
Linus Torvalds 已提交
3702 3703 3704 3705 3706
}

static int selinux_file_send_sigiotask(struct task_struct *tsk,
				       struct fown_struct *fown, int signum)
{
3707
	struct file *file;
3708
	u32 sid = task_sid(tsk);
L
Linus Torvalds 已提交
3709 3710 3711 3712
	u32 perm;
	struct file_security_struct *fsec;

	/* struct fown_struct is never outside the context of a struct file */
3713
	file = container_of(fown, struct file, f_owner);
L
Linus Torvalds 已提交
3714 3715 3716 3717 3718 3719 3720 3721

	fsec = file->f_security;

	if (!signum)
		perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
	else
		perm = signal_to_av(signum);

3722
	return avc_has_perm(fsec->fown_sid, sid,
L
Linus Torvalds 已提交
3723 3724 3725 3726 3727
			    SECCLASS_PROCESS, perm, NULL);
}

static int selinux_file_receive(struct file *file)
{
3728 3729 3730
	const struct cred *cred = current_cred();

	return file_has_perm(cred, file, file_to_av(file));
L
Linus Torvalds 已提交
3731 3732
}

3733
static int selinux_file_open(struct file *file, const struct cred *cred)
3734 3735 3736
{
	struct file_security_struct *fsec;
	struct inode_security_struct *isec;
D
David Howells 已提交
3737

3738
	fsec = file->f_security;
3739
	isec = inode_security(file_inode(file));
3740 3741 3742 3743 3744 3745 3746 3747 3748 3749 3750 3751 3752 3753 3754 3755 3756
	/*
	 * Save inode label and policy sequence number
	 * at open-time so that selinux_file_permission
	 * can determine whether revalidation is necessary.
	 * Task label is already saved in the file security
	 * struct as its SID.
	 */
	fsec->isid = isec->sid;
	fsec->pseqno = avc_policy_seqno();
	/*
	 * Since the inode label or policy seqno may have changed
	 * between the selinux_inode_permission check and the saving
	 * of state above, recheck that access is still permitted.
	 * Otherwise, access might never be revalidated against the
	 * new inode label or new policy.
	 * This check is not redundant - do not remove.
	 */
3757
	return file_path_has_perm(cred, file, open_file_to_av(file));
3758 3759
}

L
Linus Torvalds 已提交
3760 3761
/* task security operations */

3762 3763
static int selinux_task_alloc(struct task_struct *task,
			      unsigned long clone_flags)
L
Linus Torvalds 已提交
3764
{
3765 3766 3767
	u32 sid = current_sid();

	return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
L
Linus Torvalds 已提交
3768 3769
}

3770 3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781 3782 3783 3784
/*
 * allocate the SELinux part of blank credentials
 */
static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
{
	struct task_security_struct *tsec;

	tsec = kzalloc(sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;

	cred->security = tsec;
	return 0;
}

D
David Howells 已提交
3785 3786 3787 3788
/*
 * detach and free the LSM part of a set of credentials
 */
static void selinux_cred_free(struct cred *cred)
L
Linus Torvalds 已提交
3789
{
D
David Howells 已提交
3790
	struct task_security_struct *tsec = cred->security;
3791

3792 3793 3794 3795 3796
	/*
	 * cred->security == NULL if security_cred_alloc_blank() or
	 * security_prepare_creds() returned an error.
	 */
	BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3797
	cred->security = (void *) 0x7UL;
D
David Howells 已提交
3798 3799
	kfree(tsec);
}
L
Linus Torvalds 已提交
3800

D
David Howells 已提交
3801 3802 3803 3804 3805 3806 3807 3808
/*
 * prepare a new set of credentials for modification
 */
static int selinux_cred_prepare(struct cred *new, const struct cred *old,
				gfp_t gfp)
{
	const struct task_security_struct *old_tsec;
	struct task_security_struct *tsec;
L
Linus Torvalds 已提交
3809

D
David Howells 已提交
3810
	old_tsec = old->security;
L
Linus Torvalds 已提交
3811

D
David Howells 已提交
3812 3813 3814
	tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
	if (!tsec)
		return -ENOMEM;
L
Linus Torvalds 已提交
3815

D
David Howells 已提交
3816
	new->security = tsec;
L
Linus Torvalds 已提交
3817 3818 3819
	return 0;
}

3820 3821 3822 3823 3824 3825 3826 3827 3828 3829 3830
/*
 * transfer the SELinux data to a blank set of creds
 */
static void selinux_cred_transfer(struct cred *new, const struct cred *old)
{
	const struct task_security_struct *old_tsec = old->security;
	struct task_security_struct *tsec = new->security;

	*tsec = *old_tsec;
}

3831 3832 3833 3834 3835 3836 3837 3838 3839 3840 3841 3842 3843 3844 3845 3846 3847 3848 3849 3850 3851 3852 3853 3854 3855 3856 3857 3858 3859
/*
 * set the security data for a kernel service
 * - all the creation contexts are set to unlabelled
 */
static int selinux_kernel_act_as(struct cred *new, u32 secid)
{
	struct task_security_struct *tsec = new->security;
	u32 sid = current_sid();
	int ret;

	ret = avc_has_perm(sid, secid,
			   SECCLASS_KERNEL_SERVICE,
			   KERNEL_SERVICE__USE_AS_OVERRIDE,
			   NULL);
	if (ret == 0) {
		tsec->sid = secid;
		tsec->create_sid = 0;
		tsec->keycreate_sid = 0;
		tsec->sockcreate_sid = 0;
	}
	return ret;
}

/*
 * set the file creation context in a security record to the same as the
 * objective context of the specified inode
 */
static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
{
3860
	struct inode_security_struct *isec = inode_security(inode);
3861 3862 3863 3864 3865 3866 3867 3868 3869 3870 3871
	struct task_security_struct *tsec = new->security;
	u32 sid = current_sid();
	int ret;

	ret = avc_has_perm(sid, isec->sid,
			   SECCLASS_KERNEL_SERVICE,
			   KERNEL_SERVICE__CREATE_FILES_AS,
			   NULL);

	if (ret == 0)
		tsec->create_sid = isec->sid;
3872
	return ret;
3873 3874
}

3875
static int selinux_kernel_module_request(char *kmod_name)
3876
{
3877 3878
	struct common_audit_data ad;

3879
	ad.type = LSM_AUDIT_DATA_KMOD;
3880 3881
	ad.u.kmod_name = kmod_name;

3882
	return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
3883
			    SYSTEM__MODULE_REQUEST, &ad);
3884 3885
}

3886 3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899
static int selinux_kernel_module_from_file(struct file *file)
{
	struct common_audit_data ad;
	struct inode_security_struct *isec;
	struct file_security_struct *fsec;
	u32 sid = current_sid();
	int rc;

	/* init_module */
	if (file == NULL)
		return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
					SYSTEM__MODULE_LOAD, NULL);

	/* finit_module */
3900

3901 3902
	ad.type = LSM_AUDIT_DATA_FILE;
	ad.u.file = file;
3903 3904 3905 3906 3907 3908 3909 3910

	fsec = file->f_security;
	if (sid != fsec->sid) {
		rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
		if (rc)
			return rc;
	}

3911
	isec = inode_security(file_inode(file));
3912 3913 3914 3915 3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927 3928 3929 3930 3931
	return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
				SYSTEM__MODULE_LOAD, &ad);
}

static int selinux_kernel_read_file(struct file *file,
				    enum kernel_read_file_id id)
{
	int rc = 0;

	switch (id) {
	case READING_MODULE:
		rc = selinux_kernel_module_from_file(file);
		break;
	default:
		break;
	}

	return rc;
}

L
Linus Torvalds 已提交
3932 3933
static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
{
3934 3935
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETPGID, NULL);
L
Linus Torvalds 已提交
3936 3937 3938 3939
}

static int selinux_task_getpgid(struct task_struct *p)
{
3940 3941
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__GETPGID, NULL);
L
Linus Torvalds 已提交
3942 3943 3944 3945
}

static int selinux_task_getsid(struct task_struct *p)
{
3946 3947
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__GETSESSION, NULL);
L
Linus Torvalds 已提交
3948 3949
}

3950 3951
static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
{
3952
	*secid = task_sid(p);
3953 3954
}

L
Linus Torvalds 已提交
3955 3956
static int selinux_task_setnice(struct task_struct *p, int nice)
{
3957 3958
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETSCHED, NULL);
L
Linus Torvalds 已提交
3959 3960
}

3961 3962
static int selinux_task_setioprio(struct task_struct *p, int ioprio)
{
3963 3964
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETSCHED, NULL);
3965 3966
}

3967 3968
static int selinux_task_getioprio(struct task_struct *p)
{
3969 3970
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__GETSCHED, NULL);
3971 3972
}

C
Corentin LABBE 已提交
3973 3974
static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
				unsigned int flags)
3975 3976 3977
{
	u32 av = 0;

3978 3979
	if (!flags)
		return 0;
3980 3981 3982 3983 3984 3985 3986 3987
	if (flags & LSM_PRLIMIT_WRITE)
		av |= PROCESS__SETRLIMIT;
	if (flags & LSM_PRLIMIT_READ)
		av |= PROCESS__GETRLIMIT;
	return avc_has_perm(cred_sid(cred), cred_sid(tcred),
			    SECCLASS_PROCESS, av, NULL);
}

3988 3989
static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
		struct rlimit *new_rlim)
L
Linus Torvalds 已提交
3990
{
3991
	struct rlimit *old_rlim = p->signal->rlim + resource;
L
Linus Torvalds 已提交
3992 3993 3994 3995

	/* Control the ability to change the hard limit (whether
	   lowering or raising it), so that the hard limit can
	   later be used as a safe reset point for the soft limit
D
David Howells 已提交
3996
	   upon context transitions.  See selinux_bprm_committing_creds. */
L
Linus Torvalds 已提交
3997
	if (old_rlim->rlim_max != new_rlim->rlim_max)
3998 3999
		return avc_has_perm(current_sid(), task_sid(p),
				    SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
L
Linus Torvalds 已提交
4000 4001 4002 4003

	return 0;
}

4004
static int selinux_task_setscheduler(struct task_struct *p)
L
Linus Torvalds 已提交
4005
{
4006 4007
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETSCHED, NULL);
L
Linus Torvalds 已提交
4008 4009 4010 4011
}

static int selinux_task_getscheduler(struct task_struct *p)
{
4012 4013
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__GETSCHED, NULL);
L
Linus Torvalds 已提交
4014 4015
}

4016 4017
static int selinux_task_movememory(struct task_struct *p)
{
4018 4019
	return avc_has_perm(current_sid(), task_sid(p), SECCLASS_PROCESS,
			    PROCESS__SETSCHED, NULL);
4020 4021
}

4022 4023
static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
				int sig, u32 secid)
L
Linus Torvalds 已提交
4024 4025 4026 4027 4028 4029 4030
{
	u32 perm;

	if (!sig)
		perm = PROCESS__SIGNULL; /* null signal; existence test */
	else
		perm = signal_to_av(sig);
4031 4032 4033
	if (!secid)
		secid = current_sid();
	return avc_has_perm(secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
L
Linus Torvalds 已提交
4034 4035 4036 4037 4038 4039
}

static void selinux_task_to_inode(struct task_struct *p,
				  struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;
4040
	u32 sid = task_sid(p);
L
Linus Torvalds 已提交
4041

4042
	spin_lock(&isec->lock);
4043
	isec->sclass = inode_mode_to_security_class(inode->i_mode);
4044
	isec->sid = sid;
4045
	isec->initialized = LABEL_INITIALIZED;
4046
	spin_unlock(&isec->lock);
L
Linus Torvalds 已提交
4047 4048 4049
}

/* Returns error only if unable to parse addresses */
4050
static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4051
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
4052 4053 4054 4055
{
	int offset, ihlen, ret = -EINVAL;
	struct iphdr _iph, *ih;

4056
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
4057 4058 4059 4060 4061 4062 4063 4064
	ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
	if (ih == NULL)
		goto out;

	ihlen = ih->ihl * 4;
	if (ihlen < sizeof(_iph))
		goto out;

4065 4066
	ad->u.net->v4info.saddr = ih->saddr;
	ad->u.net->v4info.daddr = ih->daddr;
L
Linus Torvalds 已提交
4067 4068
	ret = 0;

4069 4070 4071
	if (proto)
		*proto = ih->protocol;

L
Linus Torvalds 已提交
4072
	switch (ih->protocol) {
4073 4074
	case IPPROTO_TCP: {
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
4075

4076 4077
		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;
L
Linus Torvalds 已提交
4078 4079 4080 4081 4082 4083

		offset += ihlen;
		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
		if (th == NULL)
			break;

4084 4085
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
4086
		break;
4087 4088 4089 4090 4091 4092 4093 4094
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;

L
Linus Torvalds 已提交
4095
		offset += ihlen;
4096
		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
L
Linus Torvalds 已提交
4097
		if (uh == NULL)
4098
			break;
L
Linus Torvalds 已提交
4099

4100 4101
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
4102 4103
		break;
	}
L
Linus Torvalds 已提交
4104

J
James Morris 已提交
4105 4106 4107 4108 4109 4110 4111 4112 4113 4114 4115
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

		if (ntohs(ih->frag_off) & IP_OFFSET)
			break;

		offset += ihlen;
		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
		if (dh == NULL)
			break;

4116 4117
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
4118
		break;
4119
	}
J
James Morris 已提交
4120

4121 4122 4123
	default:
		break;
	}
L
Linus Torvalds 已提交
4124 4125 4126 4127
out:
	return ret;
}

4128
#if IS_ENABLED(CONFIG_IPV6)
L
Linus Torvalds 已提交
4129 4130

/* Returns error only if unable to parse addresses */
4131
static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4132
			struct common_audit_data *ad, u8 *proto)
L
Linus Torvalds 已提交
4133 4134 4135 4136
{
	u8 nexthdr;
	int ret = -EINVAL, offset;
	struct ipv6hdr _ipv6h, *ip6;
4137
	__be16 frag_off;
L
Linus Torvalds 已提交
4138

4139
	offset = skb_network_offset(skb);
L
Linus Torvalds 已提交
4140 4141 4142 4143
	ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
	if (ip6 == NULL)
		goto out;

4144 4145
	ad->u.net->v6info.saddr = ip6->saddr;
	ad->u.net->v6info.daddr = ip6->daddr;
L
Linus Torvalds 已提交
4146 4147 4148 4149
	ret = 0;

	nexthdr = ip6->nexthdr;
	offset += sizeof(_ipv6h);
4150
	offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
L
Linus Torvalds 已提交
4151 4152 4153
	if (offset < 0)
		goto out;

4154 4155 4156
	if (proto)
		*proto = nexthdr;

L
Linus Torvalds 已提交
4157 4158
	switch (nexthdr) {
	case IPPROTO_TCP: {
4159
		struct tcphdr _tcph, *th;
L
Linus Torvalds 已提交
4160 4161 4162 4163 4164

		th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
		if (th == NULL)
			break;

4165 4166
		ad->u.net->sport = th->source;
		ad->u.net->dport = th->dest;
L
Linus Torvalds 已提交
4167 4168 4169 4170 4171 4172 4173 4174 4175 4176
		break;
	}

	case IPPROTO_UDP: {
		struct udphdr _udph, *uh;

		uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
		if (uh == NULL)
			break;

4177 4178
		ad->u.net->sport = uh->source;
		ad->u.net->dport = uh->dest;
L
Linus Torvalds 已提交
4179 4180 4181
		break;
	}

J
James Morris 已提交
4182 4183 4184 4185 4186 4187 4188
	case IPPROTO_DCCP: {
		struct dccp_hdr _dccph, *dh;

		dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
		if (dh == NULL)
			break;

4189 4190
		ad->u.net->sport = dh->dccph_sport;
		ad->u.net->dport = dh->dccph_dport;
J
James Morris 已提交
4191
		break;
4192
	}
J
James Morris 已提交
4193

L
Linus Torvalds 已提交
4194 4195 4196 4197 4198 4199 4200 4201 4202 4203
	/* includes fragments */
	default:
		break;
	}
out:
	return ret;
}

#endif /* IPV6 */

4204
static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4205
			     char **_addrp, int src, u8 *proto)
L
Linus Torvalds 已提交
4206
{
4207 4208
	char *addrp;
	int ret;
L
Linus Torvalds 已提交
4209

4210
	switch (ad->u.net->family) {
L
Linus Torvalds 已提交
4211
	case PF_INET:
4212
		ret = selinux_parse_skb_ipv4(skb, ad, proto);
4213 4214
		if (ret)
			goto parse_error;
4215 4216
		addrp = (char *)(src ? &ad->u.net->v4info.saddr :
				       &ad->u.net->v4info.daddr);
4217
		goto okay;
L
Linus Torvalds 已提交
4218

4219
#if IS_ENABLED(CONFIG_IPV6)
L
Linus Torvalds 已提交
4220
	case PF_INET6:
4221
		ret = selinux_parse_skb_ipv6(skb, ad, proto);
4222 4223
		if (ret)
			goto parse_error;
4224 4225
		addrp = (char *)(src ? &ad->u.net->v6info.saddr :
				       &ad->u.net->v6info.daddr);
4226
		goto okay;
L
Linus Torvalds 已提交
4227 4228
#endif	/* IPV6 */
	default:
4229 4230
		addrp = NULL;
		goto okay;
L
Linus Torvalds 已提交
4231 4232
	}

4233 4234 4235 4236
parse_error:
	printk(KERN_WARNING
	       "SELinux: failure in selinux_parse_skb(),"
	       " unable to parse packet\n");
L
Linus Torvalds 已提交
4237
	return ret;
4238 4239 4240 4241 4242

okay:
	if (_addrp)
		*_addrp = addrp;
	return 0;
L
Linus Torvalds 已提交
4243 4244
}

4245
/**
4246
 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4247
 * @skb: the packet
4248
 * @family: protocol family
4249
 * @sid: the packet's peer label SID
4250 4251
 *
 * Description:
4252 4253 4254 4255 4256 4257
 * Check the various different forms of network peer labeling and determine
 * the peer label/SID for the packet; most of the magic actually occurs in
 * the security server function security_net_peersid_cmp().  The function
 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
 * or -EACCES if @sid is invalid due to inconsistencies with the different
 * peer labels.
4258 4259
 *
 */
4260
static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4261
{
4262
	int err;
4263 4264
	u32 xfrm_sid;
	u32 nlbl_sid;
4265
	u32 nlbl_type;
4266

4267
	err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4268 4269 4270 4271 4272
	if (unlikely(err))
		return -EACCES;
	err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
	if (unlikely(err))
		return -EACCES;
4273

4274 4275 4276 4277 4278
	err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
	if (unlikely(err)) {
		printk(KERN_WARNING
		       "SELinux: failure in selinux_skb_peerlbl_sid(),"
		       " unable to determine packet's peer label\n");
4279
		return -EACCES;
4280
	}
4281 4282

	return 0;
4283 4284
}

4285 4286 4287 4288 4289 4290 4291 4292 4293 4294 4295 4296 4297 4298 4299 4300 4301 4302 4303 4304 4305 4306 4307 4308
/**
 * selinux_conn_sid - Determine the child socket label for a connection
 * @sk_sid: the parent socket's SID
 * @skb_sid: the packet's SID
 * @conn_sid: the resulting connection SID
 *
 * If @skb_sid is valid then the user:role:type information from @sk_sid is
 * combined with the MLS information from @skb_sid in order to create
 * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
 * of @sk_sid.  Returns zero on success, negative values on failure.
 *
 */
static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
{
	int err = 0;

	if (skb_sid != SECSID_NULL)
		err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
	else
		*conn_sid = sk_sid;

	return err;
}

L
Linus Torvalds 已提交
4309
/* socket security operations */
4310

4311 4312
static int socket_sockcreate_sid(const struct task_security_struct *tsec,
				 u16 secclass, u32 *socksid)
4313
{
4314 4315 4316 4317 4318 4319 4320
	if (tsec->sockcreate_sid > SECSID_NULL) {
		*socksid = tsec->sockcreate_sid;
		return 0;
	}

	return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
				       socksid);
4321 4322
}

4323
static int sock_has_perm(struct sock *sk, u32 perms)
L
Linus Torvalds 已提交
4324
{
4325
	struct sk_security_struct *sksec = sk->sk_security;
4326
	struct common_audit_data ad;
4327
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4328

4329 4330
	if (sksec->sid == SECINITSID_KERNEL)
		return 0;
L
Linus Torvalds 已提交
4331

4332
	ad.type = LSM_AUDIT_DATA_NET;
4333 4334
	ad.u.net = &net;
	ad.u.net->sk = sk;
L
Linus Torvalds 已提交
4335

4336 4337
	return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
			    &ad);
L
Linus Torvalds 已提交
4338 4339 4340 4341 4342
}

static int selinux_socket_create(int family, int type,
				 int protocol, int kern)
{
4343
	const struct task_security_struct *tsec = current_security();
4344
	u32 newsid;
4345
	u16 secclass;
4346
	int rc;
L
Linus Torvalds 已提交
4347 4348

	if (kern)
4349
		return 0;
4350 4351

	secclass = socket_type_to_security_class(family, type, protocol);
4352 4353 4354 4355
	rc = socket_sockcreate_sid(tsec, secclass, &newsid);
	if (rc)
		return rc;

4356
	return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
L
Linus Torvalds 已提交
4357 4358
}

V
Venkat Yekkirala 已提交
4359 4360
static int selinux_socket_post_create(struct socket *sock, int family,
				      int type, int protocol, int kern)
L
Linus Torvalds 已提交
4361
{
4362
	const struct task_security_struct *tsec = current_security();
4363
	struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4364
	struct sk_security_struct *sksec;
4365 4366
	u16 sclass = socket_type_to_security_class(family, type, protocol);
	u32 sid = SECINITSID_KERNEL;
4367 4368
	int err = 0;

4369 4370
	if (!kern) {
		err = socket_sockcreate_sid(tsec, sclass, &sid);
4371 4372 4373
		if (err)
			return err;
	}
4374

4375 4376
	isec->sclass = sclass;
	isec->sid = sid;
4377
	isec->initialized = LABEL_INITIALIZED;
L
Linus Torvalds 已提交
4378

4379 4380
	if (sock->sk) {
		sksec = sock->sk->sk_security;
4381 4382
		sksec->sclass = sclass;
		sksec->sid = sid;
4383
		err = selinux_netlbl_socket_post_create(sock->sk, family);
4384 4385
	}

V
Venkat Yekkirala 已提交
4386
	return err;
L
Linus Torvalds 已提交
4387 4388 4389 4390 4391 4392 4393 4394
}

/* Range of port numbers used to automatically bind.
   Need to determine whether we should perform a name_bind
   permission check between the socket and the port number. */

static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
{
4395
	struct sock *sk = sock->sk;
L
Linus Torvalds 已提交
4396 4397 4398
	u16 family;
	int err;

4399
	err = sock_has_perm(sk, SOCKET__BIND);
L
Linus Torvalds 已提交
4400 4401 4402 4403 4404
	if (err)
		goto out;

	/*
	 * If PF_INET or PF_INET6, check name_bind permission for the port.
4405 4406
	 * Multiple address binding for SCTP is not supported yet: we just
	 * check the first address now.
L
Linus Torvalds 已提交
4407
	 */
4408
	family = sk->sk_family;
L
Linus Torvalds 已提交
4409 4410
	if (family == PF_INET || family == PF_INET6) {
		char *addrp;
4411
		struct sk_security_struct *sksec = sk->sk_security;
4412
		struct common_audit_data ad;
4413
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4414 4415 4416
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
4417
		u32 sid, node_perm;
L
Linus Torvalds 已提交
4418 4419

		if (family == PF_INET) {
4420 4421 4422 4423
			if (addrlen < sizeof(struct sockaddr_in)) {
				err = -EINVAL;
				goto out;
			}
L
Linus Torvalds 已提交
4424 4425 4426 4427
			addr4 = (struct sockaddr_in *)address;
			snum = ntohs(addr4->sin_port);
			addrp = (char *)&addr4->sin_addr.s_addr;
		} else {
4428 4429 4430 4431
			if (addrlen < SIN6_LEN_RFC2133) {
				err = -EINVAL;
				goto out;
			}
L
Linus Torvalds 已提交
4432 4433 4434 4435 4436
			addr6 = (struct sockaddr_in6 *)address;
			snum = ntohs(addr6->sin6_port);
			addrp = (char *)&addr6->sin6_addr.s6_addr;
		}

4437 4438 4439
		if (snum) {
			int low, high;

4440
			inet_get_local_port_range(sock_net(sk), &low, &high);
4441

4442 4443
			if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
			    snum > high) {
P
Paul Moore 已提交
4444 4445
				err = sel_netport_sid(sk->sk_protocol,
						      snum, &sid);
4446 4447
				if (err)
					goto out;
4448
				ad.type = LSM_AUDIT_DATA_NET;
4449 4450 4451
				ad.u.net = &net;
				ad.u.net->sport = htons(snum);
				ad.u.net->family = family;
4452 4453
				err = avc_has_perm(sksec->sid, sid,
						   sksec->sclass,
4454 4455 4456 4457
						   SOCKET__NAME_BIND, &ad);
				if (err)
					goto out;
			}
L
Linus Torvalds 已提交
4458
		}
4459

4460
		switch (sksec->sclass) {
4461
		case SECCLASS_TCP_SOCKET:
L
Linus Torvalds 已提交
4462 4463
			node_perm = TCP_SOCKET__NODE_BIND;
			break;
4464

4465
		case SECCLASS_UDP_SOCKET:
L
Linus Torvalds 已提交
4466 4467
			node_perm = UDP_SOCKET__NODE_BIND;
			break;
J
James Morris 已提交
4468 4469 4470 4471 4472

		case SECCLASS_DCCP_SOCKET:
			node_perm = DCCP_SOCKET__NODE_BIND;
			break;

L
Linus Torvalds 已提交
4473 4474 4475 4476
		default:
			node_perm = RAWIP_SOCKET__NODE_BIND;
			break;
		}
4477

4478
		err = sel_netnode_sid(addrp, family, &sid);
L
Linus Torvalds 已提交
4479 4480
		if (err)
			goto out;
4481

4482
		ad.type = LSM_AUDIT_DATA_NET;
4483 4484 4485
		ad.u.net = &net;
		ad.u.net->sport = htons(snum);
		ad.u.net->family = family;
L
Linus Torvalds 已提交
4486 4487

		if (family == PF_INET)
4488
			ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
L
Linus Torvalds 已提交
4489
		else
4490
			ad.u.net->v6info.saddr = addr6->sin6_addr;
L
Linus Torvalds 已提交
4491

4492 4493
		err = avc_has_perm(sksec->sid, sid,
				   sksec->sclass, node_perm, &ad);
L
Linus Torvalds 已提交
4494 4495 4496 4497 4498 4499 4500 4501 4502
		if (err)
			goto out;
	}
out:
	return err;
}

static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
{
4503
	struct sock *sk = sock->sk;
4504
	struct sk_security_struct *sksec = sk->sk_security;
L
Linus Torvalds 已提交
4505 4506
	int err;

4507
	err = sock_has_perm(sk, SOCKET__CONNECT);
L
Linus Torvalds 已提交
4508 4509 4510 4511
	if (err)
		return err;

	/*
J
James Morris 已提交
4512
	 * If a TCP or DCCP socket, check name_connect permission for the port.
L
Linus Torvalds 已提交
4513
	 */
4514 4515
	if (sksec->sclass == SECCLASS_TCP_SOCKET ||
	    sksec->sclass == SECCLASS_DCCP_SOCKET) {
4516
		struct common_audit_data ad;
4517
		struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4518 4519 4520
		struct sockaddr_in *addr4 = NULL;
		struct sockaddr_in6 *addr6 = NULL;
		unsigned short snum;
J
James Morris 已提交
4521
		u32 sid, perm;
L
Linus Torvalds 已提交
4522 4523 4524

		if (sk->sk_family == PF_INET) {
			addr4 = (struct sockaddr_in *)address;
4525
			if (addrlen < sizeof(struct sockaddr_in))
L
Linus Torvalds 已提交
4526 4527 4528 4529
				return -EINVAL;
			snum = ntohs(addr4->sin_port);
		} else {
			addr6 = (struct sockaddr_in6 *)address;
4530
			if (addrlen < SIN6_LEN_RFC2133)
L
Linus Torvalds 已提交
4531 4532 4533 4534
				return -EINVAL;
			snum = ntohs(addr6->sin6_port);
		}

P
Paul Moore 已提交
4535
		err = sel_netport_sid(sk->sk_protocol, snum, &sid);
L
Linus Torvalds 已提交
4536 4537 4538
		if (err)
			goto out;

4539
		perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
J
James Morris 已提交
4540 4541
		       TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;

4542
		ad.type = LSM_AUDIT_DATA_NET;
4543 4544 4545
		ad.u.net = &net;
		ad.u.net->dport = htons(snum);
		ad.u.net->family = sk->sk_family;
4546
		err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
L
Linus Torvalds 已提交
4547 4548 4549 4550
		if (err)
			goto out;
	}

4551 4552
	err = selinux_netlbl_socket_connect(sk, address);

L
Linus Torvalds 已提交
4553 4554 4555 4556 4557 4558
out:
	return err;
}

static int selinux_socket_listen(struct socket *sock, int backlog)
{
4559
	return sock_has_perm(sock->sk, SOCKET__LISTEN);
L
Linus Torvalds 已提交
4560 4561 4562 4563 4564 4565 4566
}

static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
{
	int err;
	struct inode_security_struct *isec;
	struct inode_security_struct *newisec;
4567 4568
	u16 sclass;
	u32 sid;
L
Linus Torvalds 已提交
4569

4570
	err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
L
Linus Torvalds 已提交
4571 4572 4573
	if (err)
		return err;

4574
	isec = inode_security_novalidate(SOCK_INODE(sock));
4575 4576 4577 4578 4579 4580 4581 4582
	spin_lock(&isec->lock);
	sclass = isec->sclass;
	sid = isec->sid;
	spin_unlock(&isec->lock);

	newisec = inode_security_novalidate(SOCK_INODE(newsock));
	newisec->sclass = sclass;
	newisec->sid = sid;
4583
	newisec->initialized = LABEL_INITIALIZED;
L
Linus Torvalds 已提交
4584 4585 4586 4587 4588

	return 0;
}

static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4589
				  int size)
L
Linus Torvalds 已提交
4590
{
4591
	return sock_has_perm(sock->sk, SOCKET__WRITE);
L
Linus Torvalds 已提交
4592 4593 4594 4595 4596
}

static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
				  int size, int flags)
{
4597
	return sock_has_perm(sock->sk, SOCKET__READ);
L
Linus Torvalds 已提交
4598 4599 4600 4601
}

static int selinux_socket_getsockname(struct socket *sock)
{
4602
	return sock_has_perm(sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4603 4604 4605 4606
}

static int selinux_socket_getpeername(struct socket *sock)
{
4607
	return sock_has_perm(sock->sk, SOCKET__GETATTR);
L
Linus Torvalds 已提交
4608 4609
}

4610
static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
L
Linus Torvalds 已提交
4611
{
4612 4613
	int err;

4614
	err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4615 4616 4617 4618
	if (err)
		return err;

	return selinux_netlbl_socket_setsockopt(sock, level, optname);
L
Linus Torvalds 已提交
4619 4620 4621 4622 4623
}

static int selinux_socket_getsockopt(struct socket *sock, int level,
				     int optname)
{
4624
	return sock_has_perm(sock->sk, SOCKET__GETOPT);
L
Linus Torvalds 已提交
4625 4626 4627 4628
}

static int selinux_socket_shutdown(struct socket *sock, int how)
{
4629
	return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
L
Linus Torvalds 已提交
4630 4631
}

4632 4633
static int selinux_socket_unix_stream_connect(struct sock *sock,
					      struct sock *other,
L
Linus Torvalds 已提交
4634 4635
					      struct sock *newsk)
{
4636 4637
	struct sk_security_struct *sksec_sock = sock->sk_security;
	struct sk_security_struct *sksec_other = other->sk_security;
4638
	struct sk_security_struct *sksec_new = newsk->sk_security;
4639
	struct common_audit_data ad;
4640
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4641 4642
	int err;

4643
	ad.type = LSM_AUDIT_DATA_NET;
4644 4645
	ad.u.net = &net;
	ad.u.net->sk = other;
L
Linus Torvalds 已提交
4646

4647 4648
	err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
			   sksec_other->sclass,
L
Linus Torvalds 已提交
4649 4650 4651 4652 4653
			   UNIX_STREAM_SOCKET__CONNECTTO, &ad);
	if (err)
		return err;

	/* server child socket */
4654 4655 4656 4657 4658
	sksec_new->peer_sid = sksec_sock->sid;
	err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
				    &sksec_new->sid);
	if (err)
		return err;
4659

4660 4661 4662 4663
	/* connecting socket */
	sksec_sock->peer_sid = sksec_new->sid;

	return 0;
L
Linus Torvalds 已提交
4664 4665 4666 4667 4668
}

static int selinux_socket_unix_may_send(struct socket *sock,
					struct socket *other)
{
4669 4670
	struct sk_security_struct *ssec = sock->sk->sk_security;
	struct sk_security_struct *osec = other->sk->sk_security;
4671
	struct common_audit_data ad;
4672
	struct lsm_network_audit net = {0,};
L
Linus Torvalds 已提交
4673

4674
	ad.type = LSM_AUDIT_DATA_NET;
4675 4676
	ad.u.net = &net;
	ad.u.net->sk = other->sk;
L
Linus Torvalds 已提交
4677

4678 4679
	return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
			    &ad);
L
Linus Torvalds 已提交
4680 4681
}

4682 4683
static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
				    char *addrp, u16 family, u32 peer_sid,
4684
				    struct common_audit_data *ad)
4685 4686 4687 4688 4689
{
	int err;
	u32 if_sid;
	u32 node_sid;

4690
	err = sel_netif_sid(ns, ifindex, &if_sid);
4691 4692 4693 4694 4695 4696 4697 4698 4699 4700 4701 4702 4703 4704
	if (err)
		return err;
	err = avc_has_perm(peer_sid, if_sid,
			   SECCLASS_NETIF, NETIF__INGRESS, ad);
	if (err)
		return err;

	err = sel_netnode_sid(addrp, family, &node_sid);
	if (err)
		return err;
	return avc_has_perm(peer_sid, node_sid,
			    SECCLASS_NODE, NODE__RECVFROM, ad);
}

4705
static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4706
				       u16 family)
4707
{
4708
	int err = 0;
4709 4710
	struct sk_security_struct *sksec = sk->sk_security;
	u32 sk_sid = sksec->sid;
4711
	struct common_audit_data ad;
4712
	struct lsm_network_audit net = {0,};
4713 4714
	char *addrp;

4715
	ad.type = LSM_AUDIT_DATA_NET;
4716 4717 4718
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4719 4720 4721
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
	if (err)
		return err;
L
Linus Torvalds 已提交
4722

4723
	if (selinux_secmark_enabled()) {
4724
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4725
				   PACKET__RECV, &ad);
4726 4727 4728
		if (err)
			return err;
	}
4729

4730 4731 4732 4733
	err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
	if (err)
		return err;
	err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4734

4735 4736 4737 4738 4739
	return err;
}

static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
{
4740
	int err;
4741
	struct sk_security_struct *sksec = sk->sk_security;
4742 4743
	u16 family = sk->sk_family;
	u32 sk_sid = sksec->sid;
4744
	struct common_audit_data ad;
4745
	struct lsm_network_audit net = {0,};
4746
	char *addrp;
4747 4748
	u8 secmark_active;
	u8 peerlbl_active;
4749 4750

	if (family != PF_INET && family != PF_INET6)
4751
		return 0;
4752 4753

	/* Handle mapped IPv4 packets arriving via IPv6 sockets */
A
Al Viro 已提交
4754
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4755 4756
		family = PF_INET;

4757 4758 4759 4760
	/* If any sort of compatibility mode is enabled then handoff processing
	 * to the selinux_sock_rcv_skb_compat() function to deal with the
	 * special handling.  We do this in an attempt to keep this function
	 * as fast and as clean as possible. */
4761
	if (!selinux_policycap_netpeer)
4762 4763 4764
		return selinux_sock_rcv_skb_compat(sk, skb, family);

	secmark_active = selinux_secmark_enabled();
4765
	peerlbl_active = selinux_peerlbl_enabled();
4766 4767 4768
	if (!secmark_active && !peerlbl_active)
		return 0;

4769
	ad.type = LSM_AUDIT_DATA_NET;
4770 4771 4772
	ad.u.net = &net;
	ad.u.net->netif = skb->skb_iif;
	ad.u.net->family = family;
4773
	err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4774
	if (err)
4775
		return err;
4776

4777
	if (peerlbl_active) {
4778 4779 4780
		u32 peer_sid;

		err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4781 4782
		if (err)
			return err;
4783 4784
		err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
					       addrp, family, peer_sid, &ad);
4785
		if (err) {
4786
			selinux_netlbl_err(skb, family, err, 0);
4787
			return err;
4788
		}
4789 4790
		err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
				   PEER__RECV, &ad);
C
Chad Hanson 已提交
4791
		if (err) {
4792
			selinux_netlbl_err(skb, family, err, 0);
C
Chad Hanson 已提交
4793 4794
			return err;
		}
4795 4796
	}

4797
	if (secmark_active) {
4798 4799 4800 4801 4802 4803
		err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
				   PACKET__RECV, &ad);
		if (err)
			return err;
	}

4804
	return err;
L
Linus Torvalds 已提交
4805 4806
}

C
Catherine Zhang 已提交
4807 4808
static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
					    int __user *optlen, unsigned len)
L
Linus Torvalds 已提交
4809 4810 4811 4812
{
	int err = 0;
	char *scontext;
	u32 scontext_len;
4813
	struct sk_security_struct *sksec = sock->sk->sk_security;
4814
	u32 peer_sid = SECSID_NULL;
L
Linus Torvalds 已提交
4815

4816 4817
	if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
	    sksec->sclass == SECCLASS_TCP_SOCKET)
4818
		peer_sid = sksec->peer_sid;
4819 4820
	if (peer_sid == SECSID_NULL)
		return -ENOPROTOOPT;
L
Linus Torvalds 已提交
4821

C
Catherine Zhang 已提交
4822
	err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
L
Linus Torvalds 已提交
4823
	if (err)
4824
		return err;
L
Linus Torvalds 已提交
4825 4826 4827 4828 4829 4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840

	if (scontext_len > len) {
		err = -ERANGE;
		goto out_len;
	}

	if (copy_to_user(optval, scontext, scontext_len))
		err = -EFAULT;

out_len:
	if (put_user(scontext_len, optlen))
		err = -EFAULT;
	kfree(scontext);
	return err;
}

4841
static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
C
Catherine Zhang 已提交
4842
{
4843
	u32 peer_secid = SECSID_NULL;
4844
	u16 family;
4845
	struct inode_security_struct *isec;
C
Catherine Zhang 已提交
4846

4847 4848 4849 4850 4851
	if (skb && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;
	else if (skb && skb->protocol == htons(ETH_P_IPV6))
		family = PF_INET6;
	else if (sock)
4852 4853 4854 4855
		family = sock->sk->sk_family;
	else
		goto out;

4856 4857 4858 4859
	if (sock && family == PF_UNIX) {
		isec = inode_security_novalidate(SOCK_INODE(sock));
		peer_secid = isec->sid;
	} else if (skb)
4860
		selinux_skb_peerlbl_sid(skb, family, &peer_secid);
C
Catherine Zhang 已提交
4861

4862
out:
4863
	*secid = peer_secid;
4864 4865 4866
	if (peer_secid == SECSID_NULL)
		return -EINVAL;
	return 0;
C
Catherine Zhang 已提交
4867 4868
}

A
Al Viro 已提交
4869
static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
L
Linus Torvalds 已提交
4870
{
4871 4872 4873 4874 4875 4876 4877 4878
	struct sk_security_struct *sksec;

	sksec = kzalloc(sizeof(*sksec), priority);
	if (!sksec)
		return -ENOMEM;

	sksec->peer_sid = SECINITSID_UNLABELED;
	sksec->sid = SECINITSID_UNLABELED;
4879
	sksec->sclass = SECCLASS_SOCKET;
4880 4881 4882 4883
	selinux_netlbl_sk_security_reset(sksec);
	sk->sk_security = sksec;

	return 0;
L
Linus Torvalds 已提交
4884 4885 4886 4887
}

static void selinux_sk_free_security(struct sock *sk)
{
4888 4889 4890 4891 4892
	struct sk_security_struct *sksec = sk->sk_security;

	sk->sk_security = NULL;
	selinux_netlbl_sk_security_free(sksec);
	kfree(sksec);
L
Linus Torvalds 已提交
4893 4894
}

4895
static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4896
{
4897 4898
	struct sk_security_struct *sksec = sk->sk_security;
	struct sk_security_struct *newsksec = newsk->sk_security;
4899

4900 4901 4902
	newsksec->sid = sksec->sid;
	newsksec->peer_sid = sksec->peer_sid;
	newsksec->sclass = sksec->sclass;
4903

4904
	selinux_netlbl_sk_security_reset(newsksec);
4905 4906
}

V
Venkat Yekkirala 已提交
4907
static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4908
{
4909
	if (!sk)
V
Venkat Yekkirala 已提交
4910
		*secid = SECINITSID_ANY_SOCKET;
4911 4912
	else {
		struct sk_security_struct *sksec = sk->sk_security;
4913

V
Venkat Yekkirala 已提交
4914
		*secid = sksec->sid;
4915
	}
4916 4917
}

4918
static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4919
{
4920 4921
	struct inode_security_struct *isec =
		inode_security_novalidate(SOCK_INODE(parent));
4922 4923
	struct sk_security_struct *sksec = sk->sk_security;

4924 4925
	if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
	    sk->sk_family == PF_UNIX)
4926
		isec->sid = sksec->sid;
4927
	sksec->sclass = isec->sclass;
4928 4929
}

4930 4931
static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
				     struct request_sock *req)
4932 4933 4934
{
	struct sk_security_struct *sksec = sk->sk_security;
	int err;
4935
	u16 family = req->rsk_ops->family;
4936
	u32 connsid;
4937 4938
	u32 peersid;

4939
	err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4940 4941
	if (err)
		return err;
4942 4943 4944 4945 4946
	err = selinux_conn_sid(sksec->sid, peersid, &connsid);
	if (err)
		return err;
	req->secid = connsid;
	req->peer_secid = peersid;
4947

4948
	return selinux_netlbl_inet_conn_request(req, family);
4949 4950
}

4951 4952
static void selinux_inet_csk_clone(struct sock *newsk,
				   const struct request_sock *req)
4953 4954 4955 4956
{
	struct sk_security_struct *newsksec = newsk->sk_security;

	newsksec->sid = req->secid;
4957
	newsksec->peer_sid = req->peer_secid;
4958 4959 4960 4961
	/* NOTE: Ideally, we should also get the isec->sid for the
	   new socket in sync, but we don't have the isec available yet.
	   So we will wait until sock_graft to do it, by which
	   time it will have been created and available. */
4962

P
Paul Moore 已提交
4963 4964
	/* We don't need to take any sort of lock here as we are the only
	 * thread with access to newsksec */
4965
	selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4966 4967
}

4968
static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4969
{
4970
	u16 family = sk->sk_family;
4971 4972
	struct sk_security_struct *sksec = sk->sk_security;

4973 4974 4975 4976 4977
	/* handle mapped IPv4 packets arriving via IPv6 sockets */
	if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
		family = PF_INET;

	selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4978 4979
}

4980 4981 4982 4983 4984 4985 4986 4987 4988 4989 4990 4991 4992 4993 4994 4995 4996 4997 4998 4999 5000
static int selinux_secmark_relabel_packet(u32 sid)
{
	const struct task_security_struct *__tsec;
	u32 tsid;

	__tsec = current_security();
	tsid = __tsec->sid;

	return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
}

static void selinux_secmark_refcount_inc(void)
{
	atomic_inc(&selinux_secmark_refcount);
}

static void selinux_secmark_refcount_dec(void)
{
	atomic_dec(&selinux_secmark_refcount);
}

5001 5002
static void selinux_req_classify_flow(const struct request_sock *req,
				      struct flowi *fl)
5003
{
5004
	fl->flowi_secid = req->secid;
5005 5006
}

5007 5008 5009 5010 5011 5012 5013 5014 5015 5016 5017 5018 5019 5020 5021 5022 5023 5024
static int selinux_tun_dev_alloc_security(void **security)
{
	struct tun_security_struct *tunsec;

	tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
	if (!tunsec)
		return -ENOMEM;
	tunsec->sid = current_sid();

	*security = tunsec;
	return 0;
}

static void selinux_tun_dev_free_security(void *security)
{
	kfree(security);
}

5025 5026 5027 5028 5029 5030 5031 5032 5033 5034 5035 5036 5037 5038 5039
static int selinux_tun_dev_create(void)
{
	u32 sid = current_sid();

	/* we aren't taking into account the "sockcreate" SID since the socket
	 * that is being created here is not a socket in the traditional sense,
	 * instead it is a private sock, accessible only to the kernel, and
	 * representing a wide range of network traffic spanning multiple
	 * connections unlike traditional sockets - check the TUN driver to
	 * get a better understanding of why this socket is special */

	return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
			    NULL);
}

5040
static int selinux_tun_dev_attach_queue(void *security)
5041
{
5042 5043 5044 5045 5046 5047 5048 5049 5050
	struct tun_security_struct *tunsec = security;

	return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
			    TUN_SOCKET__ATTACH_QUEUE, NULL);
}

static int selinux_tun_dev_attach(struct sock *sk, void *security)
{
	struct tun_security_struct *tunsec = security;
5051 5052 5053 5054 5055 5056 5057 5058 5059
	struct sk_security_struct *sksec = sk->sk_security;

	/* we don't currently perform any NetLabel based labeling here and it
	 * isn't clear that we would want to do so anyway; while we could apply
	 * labeling without the support of the TUN user the resulting labeled
	 * traffic from the other end of the connection would almost certainly
	 * cause confusion to the TUN user that had no idea network labeling
	 * protocols were being used */

5060
	sksec->sid = tunsec->sid;
5061
	sksec->sclass = SECCLASS_TUN_SOCKET;
5062 5063

	return 0;
5064 5065
}

5066
static int selinux_tun_dev_open(void *security)
5067
{
5068
	struct tun_security_struct *tunsec = security;
5069 5070 5071
	u32 sid = current_sid();
	int err;

5072
	err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5073 5074 5075 5076 5077 5078 5079
			   TUN_SOCKET__RELABELFROM, NULL);
	if (err)
		return err;
	err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
			   TUN_SOCKET__RELABELTO, NULL);
	if (err)
		return err;
5080
	tunsec->sid = sid;
5081 5082 5083 5084

	return 0;
}

L
Linus Torvalds 已提交
5085 5086 5087 5088 5089
static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
{
	int err = 0;
	u32 perm;
	struct nlmsghdr *nlh;
5090
	struct sk_security_struct *sksec = sk->sk_security;
5091

5092
	if (skb->len < NLMSG_HDRLEN) {
L
Linus Torvalds 已提交
5093 5094 5095
		err = -EINVAL;
		goto out;
	}
5096
	nlh = nlmsg_hdr(skb);
5097

5098
	err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
L
Linus Torvalds 已提交
5099 5100
	if (err) {
		if (err == -EINVAL) {
5101 5102 5103
			pr_warn_ratelimited("SELinux: unrecognized netlink"
			       " message: protocol=%hu nlmsg_type=%hu sclass=%s"
			       " pig=%d comm=%s\n",
5104
			       sk->sk_protocol, nlh->nlmsg_type,
5105 5106
			       secclass_map[sksec->sclass - 1].name,
			       task_pid_nr(current), current->comm);
5107
			if (!selinux_enforcing || security_get_allow_unknown())
L
Linus Torvalds 已提交
5108 5109 5110 5111 5112 5113 5114 5115 5116
				err = 0;
		}

		/* Ignore */
		if (err == -ENOENT)
			err = 0;
		goto out;
	}

5117
	err = sock_has_perm(sk, perm);
L
Linus Torvalds 已提交
5118 5119 5120 5121 5122 5123
out:
	return err;
}

#ifdef CONFIG_NETFILTER

5124 5125
static unsigned int selinux_ip_forward(struct sk_buff *skb,
				       const struct net_device *indev,
5126
				       u16 family)
L
Linus Torvalds 已提交
5127
{
5128
	int err;
5129 5130
	char *addrp;
	u32 peer_sid;
5131
	struct common_audit_data ad;
5132
	struct lsm_network_audit net = {0,};
5133
	u8 secmark_active;
5134
	u8 netlbl_active;
5135
	u8 peerlbl_active;
5136

5137 5138
	if (!selinux_policycap_netpeer)
		return NF_ACCEPT;
5139

5140
	secmark_active = selinux_secmark_enabled();
5141
	netlbl_active = netlbl_enabled();
5142
	peerlbl_active = selinux_peerlbl_enabled();
5143 5144
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;
5145

5146 5147 5148
	if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
		return NF_DROP;

5149
	ad.type = LSM_AUDIT_DATA_NET;
5150
	ad.u.net = &net;
5151
	ad.u.net->netif = indev->ifindex;
5152
	ad.u.net->family = family;
5153 5154 5155
	if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
		return NF_DROP;

5156
	if (peerlbl_active) {
5157 5158
		err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
					       addrp, family, peer_sid, &ad);
5159
		if (err) {
5160
			selinux_netlbl_err(skb, family, err, 1);
5161
			return NF_DROP;
5162 5163
		}
	}
5164 5165 5166 5167 5168 5169

	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
			return NF_DROP;

5170 5171 5172 5173 5174 5175 5176 5177
	if (netlbl_active)
		/* we do this in the FORWARD path and not the POST_ROUTING
		 * path because we want to make sure we apply the necessary
		 * labeling before IPsec is applied so we can leverage AH
		 * protection */
		if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
			return NF_DROP;

5178 5179 5180
	return NF_ACCEPT;
}

5181
static unsigned int selinux_ipv4_forward(void *priv,
5182
					 struct sk_buff *skb,
5183
					 const struct nf_hook_state *state)
5184
{
5185
	return selinux_ip_forward(skb, state->in, PF_INET);
5186 5187
}

5188
#if IS_ENABLED(CONFIG_IPV6)
5189
static unsigned int selinux_ipv6_forward(void *priv,
5190
					 struct sk_buff *skb,
5191
					 const struct nf_hook_state *state)
5192
{
5193
	return selinux_ip_forward(skb, state->in, PF_INET6);
5194 5195 5196
}
#endif	/* IPV6 */

5197 5198 5199
static unsigned int selinux_ip_output(struct sk_buff *skb,
				      u16 family)
{
5200
	struct sock *sk;
5201 5202 5203 5204 5205 5206 5207 5208
	u32 sid;

	if (!netlbl_enabled())
		return NF_ACCEPT;

	/* we do this in the LOCAL_OUT path and not the POST_ROUTING path
	 * because we want to make sure we apply the necessary labeling
	 * before IPsec is applied so we can leverage AH protection */
5209 5210 5211 5212
	sk = skb->sk;
	if (sk) {
		struct sk_security_struct *sksec;

5213
		if (sk_listener(sk))
5214 5215 5216 5217 5218 5219 5220 5221 5222 5223 5224 5225 5226 5227 5228 5229
			/* if the socket is the listening state then this
			 * packet is a SYN-ACK packet which means it needs to
			 * be labeled based on the connection/request_sock and
			 * not the parent socket.  unfortunately, we can't
			 * lookup the request_sock yet as it isn't queued on
			 * the parent socket until after the SYN-ACK is sent.
			 * the "solution" is to simply pass the packet as-is
			 * as any IP option based labeling should be copied
			 * from the initial connection request (in the IP
			 * layer).  it is far from ideal, but until we get a
			 * security label in the packet itself this is the
			 * best we can do. */
			return NF_ACCEPT;

		/* standard practice, label using the parent socket */
		sksec = sk->sk_security;
5230 5231 5232 5233 5234 5235 5236 5237 5238
		sid = sksec->sid;
	} else
		sid = SECINITSID_KERNEL;
	if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
		return NF_DROP;

	return NF_ACCEPT;
}

5239
static unsigned int selinux_ipv4_output(void *priv,
5240
					struct sk_buff *skb,
5241
					const struct nf_hook_state *state)
5242 5243 5244 5245
{
	return selinux_ip_output(skb, PF_INET);
}

5246
#if IS_ENABLED(CONFIG_IPV6)
5247 5248 5249 5250 5251 5252 5253 5254
static unsigned int selinux_ipv6_output(void *priv,
					struct sk_buff *skb,
					const struct nf_hook_state *state)
{
	return selinux_ip_output(skb, PF_INET6);
}
#endif	/* IPV6 */

5255 5256
static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
						int ifindex,
5257
						u16 family)
5258
{
5259
	struct sock *sk = skb_to_full_sk(skb);
5260
	struct sk_security_struct *sksec;
5261
	struct common_audit_data ad;
5262
	struct lsm_network_audit net = {0,};
5263 5264
	char *addrp;
	u8 proto;
L
Linus Torvalds 已提交
5265

5266 5267 5268 5269
	if (sk == NULL)
		return NF_ACCEPT;
	sksec = sk->sk_security;

5270
	ad.type = LSM_AUDIT_DATA_NET;
5271 5272 5273
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
5274 5275 5276
	if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
		return NF_DROP;

5277
	if (selinux_secmark_enabled())
5278
		if (avc_has_perm(sksec->sid, skb->secmark,
5279
				 SECCLASS_PACKET, PACKET__SEND, &ad))
5280
			return NF_DROP_ERR(-ECONNREFUSED);
5281

5282 5283
	if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
		return NF_DROP_ERR(-ECONNREFUSED);
5284 5285

	return NF_ACCEPT;
5286 5287
}

5288 5289
static unsigned int selinux_ip_postroute(struct sk_buff *skb,
					 const struct net_device *outdev,
5290
					 u16 family)
5291
{
5292 5293
	u32 secmark_perm;
	u32 peer_sid;
5294
	int ifindex = outdev->ifindex;
5295
	struct sock *sk;
5296
	struct common_audit_data ad;
5297
	struct lsm_network_audit net = {0,};
5298 5299 5300
	char *addrp;
	u8 secmark_active;
	u8 peerlbl_active;
5301

5302 5303 5304 5305
	/* If any sort of compatibility mode is enabled then handoff processing
	 * to the selinux_ip_postroute_compat() function to deal with the
	 * special handling.  We do this in an attempt to keep this function
	 * as fast and as clean as possible. */
5306
	if (!selinux_policycap_netpeer)
5307
		return selinux_ip_postroute_compat(skb, ifindex, family);
5308 5309 5310 5311 5312 5313

	secmark_active = selinux_secmark_enabled();
	peerlbl_active = selinux_peerlbl_enabled();
	if (!secmark_active && !peerlbl_active)
		return NF_ACCEPT;

5314
	sk = skb_to_full_sk(skb);
5315

5316
#ifdef CONFIG_XFRM
5317 5318 5319 5320 5321
	/* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
	 * packet transformation so allow the packet to pass without any checks
	 * since we'll have another chance to perform access control checks
	 * when the packet is on it's final way out.
	 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5322 5323 5324 5325 5326 5327 5328
	 *       is NULL, in this case go ahead and apply access control.
	 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
	 *       TCP listening state we cannot wait until the XFRM processing
	 *       is done as we will miss out on the SA label if we do;
	 *       unfortunately, this means more work, but it is only once per
	 *       connection. */
	if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5329
	    !(sk && sk_listener(sk)))
5330
		return NF_ACCEPT;
5331
#endif
5332

5333
	if (sk == NULL) {
5334 5335 5336 5337
		/* Without an associated socket the packet is either coming
		 * from the kernel or it is being forwarded; check the packet
		 * to determine which and if the packet is being forwarded
		 * query the packet directly to determine the security label. */
5338 5339
		if (skb->skb_iif) {
			secmark_perm = PACKET__FORWARD_OUT;
5340
			if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5341
				return NF_DROP;
5342 5343
		} else {
			secmark_perm = PACKET__SEND;
5344
			peer_sid = SECINITSID_KERNEL;
5345
		}
5346
	} else if (sk_listener(sk)) {
5347 5348 5349 5350 5351 5352 5353 5354 5355 5356
		/* Locally generated packet but the associated socket is in the
		 * listening state which means this is a SYN-ACK packet.  In
		 * this particular case the correct security label is assigned
		 * to the connection/request_sock but unfortunately we can't
		 * query the request_sock as it isn't queued on the parent
		 * socket until after the SYN-ACK packet is sent; the only
		 * viable choice is to regenerate the label like we do in
		 * selinux_inet_conn_request().  See also selinux_ip_output()
		 * for similar problems. */
		u32 skb_sid;
5357 5358 5359
		struct sk_security_struct *sksec;

		sksec = sk->sk_security;
5360 5361
		if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
			return NF_DROP;
5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376
		/* At this point, if the returned skb peerlbl is SECSID_NULL
		 * and the packet has been through at least one XFRM
		 * transformation then we must be dealing with the "final"
		 * form of labeled IPsec packet; since we've already applied
		 * all of our access controls on this packet we can safely
		 * pass the packet. */
		if (skb_sid == SECSID_NULL) {
			switch (family) {
			case PF_INET:
				if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
					return NF_ACCEPT;
				break;
			case PF_INET6:
				if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
					return NF_ACCEPT;
5377
				break;
5378 5379 5380 5381
			default:
				return NF_DROP_ERR(-ECONNREFUSED);
			}
		}
5382 5383 5384
		if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
			return NF_DROP;
		secmark_perm = PACKET__SEND;
5385
	} else {
5386 5387
		/* Locally generated packet, fetch the security label from the
		 * associated socket. */
5388 5389 5390 5391
		struct sk_security_struct *sksec = sk->sk_security;
		peer_sid = sksec->sid;
		secmark_perm = PACKET__SEND;
	}
5392

5393
	ad.type = LSM_AUDIT_DATA_NET;
5394 5395 5396
	ad.u.net = &net;
	ad.u.net->netif = ifindex;
	ad.u.net->family = family;
5397
	if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5398
		return NF_DROP;
5399

5400 5401 5402
	if (secmark_active)
		if (avc_has_perm(peer_sid, skb->secmark,
				 SECCLASS_PACKET, secmark_perm, &ad))
5403
			return NF_DROP_ERR(-ECONNREFUSED);
5404 5405 5406 5407 5408

	if (peerlbl_active) {
		u32 if_sid;
		u32 node_sid;

5409
		if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5410
			return NF_DROP;
5411 5412
		if (avc_has_perm(peer_sid, if_sid,
				 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5413
			return NF_DROP_ERR(-ECONNREFUSED);
5414 5415

		if (sel_netnode_sid(addrp, family, &node_sid))
5416
			return NF_DROP;
5417 5418
		if (avc_has_perm(peer_sid, node_sid,
				 SECCLASS_NODE, NODE__SENDTO, &ad))
5419
			return NF_DROP_ERR(-ECONNREFUSED);
5420
	}
5421

5422
	return NF_ACCEPT;
L
Linus Torvalds 已提交
5423 5424
}

5425
static unsigned int selinux_ipv4_postroute(void *priv,
5426
					   struct sk_buff *skb,
5427
					   const struct nf_hook_state *state)
L
Linus Torvalds 已提交
5428
{
5429
	return selinux_ip_postroute(skb, state->out, PF_INET);
L
Linus Torvalds 已提交
5430 5431
}

5432
#if IS_ENABLED(CONFIG_IPV6)
5433
static unsigned int selinux_ipv6_postroute(void *priv,
5434
					   struct sk_buff *skb,
5435
					   const struct nf_hook_state *state)
L
Linus Torvalds 已提交
5436
{
5437
	return selinux_ip_postroute(skb, state->out, PF_INET6);
L
Linus Torvalds 已提交
5438 5439 5440 5441 5442 5443 5444
}
#endif	/* IPV6 */

#endif	/* CONFIG_NETFILTER */

static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
{
5445
	return selinux_nlmsg_perm(sk, skb);
L
Linus Torvalds 已提交
5446 5447
}

5448
static int ipc_alloc_security(struct kern_ipc_perm *perm,
L
Linus Torvalds 已提交
5449 5450 5451 5452
			      u16 sclass)
{
	struct ipc_security_struct *isec;

J
James Morris 已提交
5453
	isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5454 5455 5456 5457
	if (!isec)
		return -ENOMEM;

	isec->sclass = sclass;
5458
	isec->sid = current_sid();
L
Linus Torvalds 已提交
5459 5460 5461 5462 5463 5464 5465 5466 5467 5468 5469 5470 5471 5472 5473 5474
	perm->security = isec;

	return 0;
}

static void ipc_free_security(struct kern_ipc_perm *perm)
{
	struct ipc_security_struct *isec = perm->security;
	perm->security = NULL;
	kfree(isec);
}

static int msg_msg_alloc_security(struct msg_msg *msg)
{
	struct msg_security_struct *msec;

J
James Morris 已提交
5475
	msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
L
Linus Torvalds 已提交
5476 5477 5478 5479 5480 5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491 5492 5493
	if (!msec)
		return -ENOMEM;

	msec->sid = SECINITSID_UNLABELED;
	msg->security = msec;

	return 0;
}

static void msg_msg_free_security(struct msg_msg *msg)
{
	struct msg_security_struct *msec = msg->security;

	msg->security = NULL;
	kfree(msec);
}

static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5494
			u32 perms)
L
Linus Torvalds 已提交
5495 5496
{
	struct ipc_security_struct *isec;
5497
	struct common_audit_data ad;
5498
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5499 5500 5501

	isec = ipc_perms->security;

5502
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5503 5504
	ad.u.ipc_id = ipc_perms->key;

5505
	return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
L
Linus Torvalds 已提交
5506 5507 5508 5509 5510 5511 5512 5513 5514 5515 5516 5517 5518 5519 5520 5521
}

static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
{
	return msg_msg_alloc_security(msg);
}

static void selinux_msg_msg_free_security(struct msg_msg *msg)
{
	msg_msg_free_security(msg);
}

/* message queue security operations */
static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
{
	struct ipc_security_struct *isec;
5522
	struct common_audit_data ad;
5523
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5524 5525
	int rc;

5526
	rc = ipc_alloc_security(&msq->q_perm, SECCLASS_MSGQ);
L
Linus Torvalds 已提交
5527 5528 5529 5530 5531
	if (rc)
		return rc;

	isec = msq->q_perm.security;

5532
	ad.type = LSM_AUDIT_DATA_IPC;
5533
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5534

5535
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5536 5537 5538 5539 5540 5541 5542 5543 5544 5545 5546 5547 5548 5549 5550 5551
			  MSGQ__CREATE, &ad);
	if (rc) {
		ipc_free_security(&msq->q_perm);
		return rc;
	}
	return 0;
}

static void selinux_msg_queue_free_security(struct msg_queue *msq)
{
	ipc_free_security(&msq->q_perm);
}

static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
{
	struct ipc_security_struct *isec;
5552
	struct common_audit_data ad;
5553
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5554 5555 5556

	isec = msq->q_perm.security;

5557
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5558 5559
	ad.u.ipc_id = msq->q_perm.key;

5560
	return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5561 5562 5563 5564 5565 5566 5567 5568
			    MSGQ__ASSOCIATE, &ad);
}

static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
{
	int err;
	int perms;

5569
	switch (cmd) {
L
Linus Torvalds 已提交
5570 5571 5572
	case IPC_INFO:
	case MSG_INFO:
		/* No specific object, just general system-wide information. */
5573 5574
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
L
Linus Torvalds 已提交
5575 5576 5577 5578 5579 5580 5581 5582 5583 5584 5585 5586 5587 5588
	case IPC_STAT:
	case MSG_STAT:
		perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
		break;
	case IPC_SET:
		perms = MSGQ__SETATTR;
		break;
	case IPC_RMID:
		perms = MSGQ__DESTROY;
		break;
	default:
		return 0;
	}

5589
	err = ipc_has_perm(&msq->q_perm, perms);
L
Linus Torvalds 已提交
5590 5591 5592 5593 5594 5595 5596
	return err;
}

static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
{
	struct ipc_security_struct *isec;
	struct msg_security_struct *msec;
5597
	struct common_audit_data ad;
5598
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5599 5600 5601 5602 5603 5604 5605 5606 5607 5608 5609 5610 5611
	int rc;

	isec = msq->q_perm.security;
	msec = msg->security;

	/*
	 * First time through, need to assign label to the message
	 */
	if (msec->sid == SECINITSID_UNLABELED) {
		/*
		 * Compute new sid based on current process and
		 * message queue this message will be stored in
		 */
5612
		rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5613
					     NULL, &msec->sid);
L
Linus Torvalds 已提交
5614 5615 5616 5617
		if (rc)
			return rc;
	}

5618
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5619 5620 5621
	ad.u.ipc_id = msq->q_perm.key;

	/* Can this process write to the queue? */
5622
	rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
L
Linus Torvalds 已提交
5623 5624 5625
			  MSGQ__WRITE, &ad);
	if (!rc)
		/* Can this process send the message */
5626 5627
		rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
				  MSG__SEND, &ad);
L
Linus Torvalds 已提交
5628 5629
	if (!rc)
		/* Can the message be put in the queue? */
5630 5631
		rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
				  MSGQ__ENQUEUE, &ad);
L
Linus Torvalds 已提交
5632 5633 5634 5635 5636 5637 5638 5639 5640 5641

	return rc;
}

static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
				    struct task_struct *target,
				    long type, int mode)
{
	struct ipc_security_struct *isec;
	struct msg_security_struct *msec;
5642
	struct common_audit_data ad;
5643
	u32 sid = task_sid(target);
L
Linus Torvalds 已提交
5644 5645 5646 5647 5648
	int rc;

	isec = msq->q_perm.security;
	msec = msg->security;

5649
	ad.type = LSM_AUDIT_DATA_IPC;
5650
	ad.u.ipc_id = msq->q_perm.key;
L
Linus Torvalds 已提交
5651

5652
	rc = avc_has_perm(sid, isec->sid,
L
Linus Torvalds 已提交
5653 5654
			  SECCLASS_MSGQ, MSGQ__READ, &ad);
	if (!rc)
5655
		rc = avc_has_perm(sid, msec->sid,
L
Linus Torvalds 已提交
5656 5657 5658 5659 5660 5661 5662 5663
				  SECCLASS_MSG, MSG__RECEIVE, &ad);
	return rc;
}

/* Shared Memory security operations */
static int selinux_shm_alloc_security(struct shmid_kernel *shp)
{
	struct ipc_security_struct *isec;
5664
	struct common_audit_data ad;
5665
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5666 5667
	int rc;

5668
	rc = ipc_alloc_security(&shp->shm_perm, SECCLASS_SHM);
L
Linus Torvalds 已提交
5669 5670 5671 5672 5673
	if (rc)
		return rc;

	isec = shp->shm_perm.security;

5674
	ad.type = LSM_AUDIT_DATA_IPC;
5675
	ad.u.ipc_id = shp->shm_perm.key;
L
Linus Torvalds 已提交
5676

5677
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5678 5679 5680 5681 5682 5683 5684 5685 5686 5687 5688 5689 5690 5691 5692 5693
			  SHM__CREATE, &ad);
	if (rc) {
		ipc_free_security(&shp->shm_perm);
		return rc;
	}
	return 0;
}

static void selinux_shm_free_security(struct shmid_kernel *shp)
{
	ipc_free_security(&shp->shm_perm);
}

static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
{
	struct ipc_security_struct *isec;
5694
	struct common_audit_data ad;
5695
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5696 5697 5698

	isec = shp->shm_perm.security;

5699
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5700 5701
	ad.u.ipc_id = shp->shm_perm.key;

5702
	return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
L
Linus Torvalds 已提交
5703 5704 5705 5706 5707 5708 5709 5710 5711
			    SHM__ASSOCIATE, &ad);
}

/* Note, at this point, shp is locked down */
static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
{
	int perms;
	int err;

5712
	switch (cmd) {
L
Linus Torvalds 已提交
5713 5714 5715
	case IPC_INFO:
	case SHM_INFO:
		/* No specific object, just general system-wide information. */
5716 5717
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
L
Linus Torvalds 已提交
5718 5719 5720 5721 5722 5723 5724 5725 5726 5727 5728 5729 5730 5731 5732 5733 5734 5735
	case IPC_STAT:
	case SHM_STAT:
		perms = SHM__GETATTR | SHM__ASSOCIATE;
		break;
	case IPC_SET:
		perms = SHM__SETATTR;
		break;
	case SHM_LOCK:
	case SHM_UNLOCK:
		perms = SHM__LOCK;
		break;
	case IPC_RMID:
		perms = SHM__DESTROY;
		break;
	default:
		return 0;
	}

5736
	err = ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5737 5738 5739 5740 5741 5742 5743 5744 5745 5746 5747 5748 5749
	return err;
}

static int selinux_shm_shmat(struct shmid_kernel *shp,
			     char __user *shmaddr, int shmflg)
{
	u32 perms;

	if (shmflg & SHM_RDONLY)
		perms = SHM__READ;
	else
		perms = SHM__READ | SHM__WRITE;

5750
	return ipc_has_perm(&shp->shm_perm, perms);
L
Linus Torvalds 已提交
5751 5752 5753 5754 5755 5756
}

/* Semaphore security operations */
static int selinux_sem_alloc_security(struct sem_array *sma)
{
	struct ipc_security_struct *isec;
5757
	struct common_audit_data ad;
5758
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5759 5760
	int rc;

5761
	rc = ipc_alloc_security(&sma->sem_perm, SECCLASS_SEM);
L
Linus Torvalds 已提交
5762 5763 5764 5765 5766
	if (rc)
		return rc;

	isec = sma->sem_perm.security;

5767
	ad.type = LSM_AUDIT_DATA_IPC;
5768
	ad.u.ipc_id = sma->sem_perm.key;
L
Linus Torvalds 已提交
5769

5770
	rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5771 5772 5773 5774 5775 5776 5777 5778 5779 5780 5781 5782 5783 5784 5785 5786
			  SEM__CREATE, &ad);
	if (rc) {
		ipc_free_security(&sma->sem_perm);
		return rc;
	}
	return 0;
}

static void selinux_sem_free_security(struct sem_array *sma)
{
	ipc_free_security(&sma->sem_perm);
}

static int selinux_sem_associate(struct sem_array *sma, int semflg)
{
	struct ipc_security_struct *isec;
5787
	struct common_audit_data ad;
5788
	u32 sid = current_sid();
L
Linus Torvalds 已提交
5789 5790 5791

	isec = sma->sem_perm.security;

5792
	ad.type = LSM_AUDIT_DATA_IPC;
L
Linus Torvalds 已提交
5793 5794
	ad.u.ipc_id = sma->sem_perm.key;

5795
	return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
L
Linus Torvalds 已提交
5796 5797 5798 5799 5800 5801 5802 5803 5804
			    SEM__ASSOCIATE, &ad);
}

/* Note, at this point, sma is locked down */
static int selinux_sem_semctl(struct sem_array *sma, int cmd)
{
	int err;
	u32 perms;

5805
	switch (cmd) {
L
Linus Torvalds 已提交
5806 5807 5808
	case IPC_INFO:
	case SEM_INFO:
		/* No specific object, just general system-wide information. */
5809 5810
		return avc_has_perm(current_sid(), SECINITSID_KERNEL,
				    SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
L
Linus Torvalds 已提交
5811 5812 5813 5814 5815 5816 5817 5818 5819 5820 5821 5822 5823 5824 5825 5826 5827 5828 5829 5830 5831 5832 5833 5834 5835 5836 5837
	case GETPID:
	case GETNCNT:
	case GETZCNT:
		perms = SEM__GETATTR;
		break;
	case GETVAL:
	case GETALL:
		perms = SEM__READ;
		break;
	case SETVAL:
	case SETALL:
		perms = SEM__WRITE;
		break;
	case IPC_RMID:
		perms = SEM__DESTROY;
		break;
	case IPC_SET:
		perms = SEM__SETATTR;
		break;
	case IPC_STAT:
	case SEM_STAT:
		perms = SEM__GETATTR | SEM__ASSOCIATE;
		break;
	default:
		return 0;
	}

5838
	err = ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5839 5840 5841 5842 5843 5844 5845 5846 5847 5848 5849 5850 5851
	return err;
}

static int selinux_sem_semop(struct sem_array *sma,
			     struct sembuf *sops, unsigned nsops, int alter)
{
	u32 perms;

	if (alter)
		perms = SEM__READ | SEM__WRITE;
	else
		perms = SEM__READ;

5852
	return ipc_has_perm(&sma->sem_perm, perms);
L
Linus Torvalds 已提交
5853 5854 5855 5856 5857 5858 5859 5860 5861 5862 5863 5864 5865 5866 5867
}

static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
{
	u32 av = 0;

	av = 0;
	if (flag & S_IRUGO)
		av |= IPC__UNIX_READ;
	if (flag & S_IWUGO)
		av |= IPC__UNIX_WRITE;

	if (av == 0)
		return 0;

5868
	return ipc_has_perm(ipcp, av);
L
Linus Torvalds 已提交
5869 5870
}

5871 5872 5873 5874 5875 5876
static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
{
	struct ipc_security_struct *isec = ipcp->security;
	*secid = isec->sid;
}

5877
static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
L
Linus Torvalds 已提交
5878 5879 5880 5881 5882 5883
{
	if (inode)
		inode_doinit_with_dentry(inode, dentry);
}

static int selinux_getprocattr(struct task_struct *p,
5884
			       char *name, char **value)
L
Linus Torvalds 已提交
5885
{
5886
	const struct task_security_struct *__tsec;
5887
	u32 sid;
L
Linus Torvalds 已提交
5888
	int error;
5889
	unsigned len;
L
Linus Torvalds 已提交
5890

5891 5892 5893
	rcu_read_lock();
	__tsec = __task_cred(p)->security;

L
Linus Torvalds 已提交
5894
	if (current != p) {
5895 5896
		error = avc_has_perm(current_sid(), __tsec->sid,
				     SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
L
Linus Torvalds 已提交
5897
		if (error)
5898
			goto bad;
L
Linus Torvalds 已提交
5899 5900 5901
	}

	if (!strcmp(name, "current"))
5902
		sid = __tsec->sid;
L
Linus Torvalds 已提交
5903
	else if (!strcmp(name, "prev"))
5904
		sid = __tsec->osid;
L
Linus Torvalds 已提交
5905
	else if (!strcmp(name, "exec"))
5906
		sid = __tsec->exec_sid;
L
Linus Torvalds 已提交
5907
	else if (!strcmp(name, "fscreate"))
5908
		sid = __tsec->create_sid;
5909
	else if (!strcmp(name, "keycreate"))
5910
		sid = __tsec->keycreate_sid;
5911
	else if (!strcmp(name, "sockcreate"))
5912
		sid = __tsec->sockcreate_sid;
5913 5914 5915 5916
	else {
		error = -EINVAL;
		goto bad;
	}
5917
	rcu_read_unlock();
L
Linus Torvalds 已提交
5918 5919 5920 5921

	if (!sid)
		return 0;

5922 5923 5924 5925
	error = security_sid_to_context(sid, value, &len);
	if (error)
		return error;
	return len;
5926

5927
bad:
5928
	rcu_read_unlock();
5929
	return error;
L
Linus Torvalds 已提交
5930 5931
}

5932
static int selinux_setprocattr(const char *name, void *value, size_t size)
L
Linus Torvalds 已提交
5933 5934
{
	struct task_security_struct *tsec;
D
David Howells 已提交
5935
	struct cred *new;
5936
	u32 mysid = current_sid(), sid = 0, ptsid;
L
Linus Torvalds 已提交
5937 5938 5939 5940 5941 5942 5943
	int error;
	char *str = value;

	/*
	 * Basic control over ability to set these attributes at all.
	 */
	if (!strcmp(name, "exec"))
5944 5945
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETEXEC, NULL);
L
Linus Torvalds 已提交
5946
	else if (!strcmp(name, "fscreate"))
5947 5948
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETFSCREATE, NULL);
5949
	else if (!strcmp(name, "keycreate"))
5950 5951
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETKEYCREATE, NULL);
5952
	else if (!strcmp(name, "sockcreate"))
5953 5954
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETSOCKCREATE, NULL);
L
Linus Torvalds 已提交
5955
	else if (!strcmp(name, "current"))
5956 5957
		error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
				     PROCESS__SETCURRENT, NULL);
L
Linus Torvalds 已提交
5958 5959 5960 5961 5962 5963
	else
		error = -EINVAL;
	if (error)
		return error;

	/* Obtain a SID for the context, if one was specified. */
5964
	if (size && str[0] && str[0] != '\n') {
L
Linus Torvalds 已提交
5965 5966 5967 5968
		if (str[size-1] == '\n') {
			str[size-1] = 0;
			size--;
		}
5969
		error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5970
		if (error == -EINVAL && !strcmp(name, "fscreate")) {
5971
			if (!has_cap_mac_admin(true)) {
5972 5973 5974 5975 5976 5977 5978 5979 5980 5981 5982 5983 5984 5985
				struct audit_buffer *ab;
				size_t audit_size;

				/* We strip a nul only if it is at the end, otherwise the
				 * context contains a nul and we should audit that */
				if (str[size - 1] == '\0')
					audit_size = size - 1;
				else
					audit_size = size;
				ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
				audit_log_format(ab, "op=fscreate invalid_context=");
				audit_log_n_untrustedstring(ab, value, audit_size);
				audit_log_end(ab);

5986
				return error;
5987
			}
5988 5989 5990
			error = security_context_to_sid_force(value, size,
							      &sid);
		}
L
Linus Torvalds 已提交
5991 5992 5993 5994
		if (error)
			return error;
	}

D
David Howells 已提交
5995 5996 5997 5998
	new = prepare_creds();
	if (!new)
		return -ENOMEM;

L
Linus Torvalds 已提交
5999 6000 6001
	/* Permission checking based on the specified context is
	   performed during the actual operation (execve,
	   open/mkdir/...), when we know the full context of the
D
David Howells 已提交
6002
	   operation.  See selinux_bprm_set_creds for the execve
L
Linus Torvalds 已提交
6003 6004
	   checks and may_create for the file creation checks. The
	   operation will then fail if the context is not permitted. */
D
David Howells 已提交
6005 6006
	tsec = new->security;
	if (!strcmp(name, "exec")) {
L
Linus Torvalds 已提交
6007
		tsec->exec_sid = sid;
D
David Howells 已提交
6008
	} else if (!strcmp(name, "fscreate")) {
L
Linus Torvalds 已提交
6009
		tsec->create_sid = sid;
D
David Howells 已提交
6010
	} else if (!strcmp(name, "keycreate")) {
6011 6012
		error = avc_has_perm(mysid, sid, SECCLASS_KEY, KEY__CREATE,
				     NULL);
6013
		if (error)
D
David Howells 已提交
6014
			goto abort_change;
6015
		tsec->keycreate_sid = sid;
D
David Howells 已提交
6016
	} else if (!strcmp(name, "sockcreate")) {
6017
		tsec->sockcreate_sid = sid;
D
David Howells 已提交
6018 6019
	} else if (!strcmp(name, "current")) {
		error = -EINVAL;
L
Linus Torvalds 已提交
6020
		if (sid == 0)
D
David Howells 已提交
6021 6022 6023 6024
			goto abort_change;

		/* Only allow single threaded processes to change context */
		error = -EPERM;
6025
		if (!current_is_single_threaded()) {
D
David Howells 已提交
6026 6027 6028
			error = security_bounded_transition(tsec->sid, sid);
			if (error)
				goto abort_change;
6029
		}
L
Linus Torvalds 已提交
6030 6031 6032

		/* Check permissions for the transition. */
		error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6033
				     PROCESS__DYNTRANSITION, NULL);
L
Linus Torvalds 已提交
6034
		if (error)
D
David Howells 已提交
6035
			goto abort_change;
L
Linus Torvalds 已提交
6036 6037 6038

		/* Check for ptracing, and update the task SID if ok.
		   Otherwise, leave SID unchanged and fail. */
6039
		ptsid = ptrace_parent_sid();
6040
		if (ptsid != 0) {
D
David Howells 已提交
6041 6042
			error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
					     PROCESS__PTRACE, NULL);
L
Linus Torvalds 已提交
6043
			if (error)
D
David Howells 已提交
6044
				goto abort_change;
L
Linus Torvalds 已提交
6045 6046
		}

D
David Howells 已提交
6047 6048 6049 6050 6051 6052 6053
		tsec->sid = sid;
	} else {
		error = -EINVAL;
		goto abort_change;
	}

	commit_creds(new);
L
Linus Torvalds 已提交
6054
	return size;
D
David Howells 已提交
6055 6056 6057 6058

abort_change:
	abort_creds(new);
	return error;
L
Linus Torvalds 已提交
6059 6060
}

6061 6062 6063 6064 6065
static int selinux_ismaclabel(const char *name)
{
	return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
}

6066 6067 6068 6069 6070
static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
{
	return security_sid_to_context(secid, secdata, seclen);
}

6071
static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6072
{
6073
	return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
6074 6075
}

6076 6077
static void selinux_release_secctx(char *secdata, u32 seclen)
{
6078
	kfree(secdata);
6079 6080
}

6081 6082 6083 6084
static void selinux_inode_invalidate_secctx(struct inode *inode)
{
	struct inode_security_struct *isec = inode->i_security;

6085
	spin_lock(&isec->lock);
6086
	isec->initialized = LABEL_INVALID;
6087
	spin_unlock(&isec->lock);
6088 6089
}

6090 6091 6092 6093 6094 6095 6096 6097 6098 6099 6100 6101 6102 6103 6104 6105 6106 6107 6108 6109 6110 6111 6112 6113 6114 6115
/*
 *	called with inode->i_mutex locked
 */
static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
{
	return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
}

/*
 *	called with inode->i_mutex locked
 */
static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
{
	return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
}

static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
{
	int len = 0;
	len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
						ctx, true);
	if (len < 0)
		return len;
	*ctxlen = len;
	return 0;
}
6116 6117
#ifdef CONFIG_KEYS

D
David Howells 已提交
6118
static int selinux_key_alloc(struct key *k, const struct cred *cred,
6119
			     unsigned long flags)
6120
{
D
David Howells 已提交
6121
	const struct task_security_struct *tsec;
6122 6123 6124 6125 6126 6127
	struct key_security_struct *ksec;

	ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
	if (!ksec)
		return -ENOMEM;

D
David Howells 已提交
6128 6129 6130
	tsec = cred->security;
	if (tsec->keycreate_sid)
		ksec->sid = tsec->keycreate_sid;
6131
	else
D
David Howells 已提交
6132
		ksec->sid = tsec->sid;
6133

6134
	k->security = ksec;
6135 6136 6137 6138 6139 6140 6141 6142 6143 6144 6145 6146
	return 0;
}

static void selinux_key_free(struct key *k)
{
	struct key_security_struct *ksec = k->security;

	k->security = NULL;
	kfree(ksec);
}

static int selinux_key_permission(key_ref_t key_ref,
D
David Howells 已提交
6147
				  const struct cred *cred,
6148
				  unsigned perm)
6149 6150 6151
{
	struct key *key;
	struct key_security_struct *ksec;
6152
	u32 sid;
6153 6154 6155 6156 6157 6158 6159

	/* if no specific permissions are requested, we skip the
	   permission check. No serious, additional covert channels
	   appear to be created. */
	if (perm == 0)
		return 0;

D
David Howells 已提交
6160
	sid = cred_sid(cred);
6161 6162 6163 6164 6165

	key = key_ref_to_ptr(key_ref);
	ksec = key->security;

	return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6166 6167
}

6168 6169 6170 6171 6172 6173 6174 6175 6176 6177 6178 6179 6180
static int selinux_key_getsecurity(struct key *key, char **_buffer)
{
	struct key_security_struct *ksec = key->security;
	char *context = NULL;
	unsigned len;
	int rc;

	rc = security_sid_to_context(ksec->sid, &context, &len);
	if (!rc)
		rc = len;
	*_buffer = context;
	return rc;
}
6181 6182 6183
#endif

#ifdef CONFIG_SECURITY_INFINIBAND
6184 6185 6186 6187 6188 6189 6190 6191
static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
{
	struct common_audit_data ad;
	int err;
	u32 sid = 0;
	struct ib_security_struct *sec = ib_sec;
	struct lsm_ibpkey_audit ibpkey;

6192
	err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6193 6194 6195 6196 6197 6198 6199 6200 6201 6202 6203 6204
	if (err)
		return err;

	ad.type = LSM_AUDIT_DATA_IBPKEY;
	ibpkey.subnet_prefix = subnet_prefix;
	ibpkey.pkey = pkey_val;
	ad.u.ibpkey = &ibpkey;
	return avc_has_perm(sec->sid, sid,
			    SECCLASS_INFINIBAND_PKEY,
			    INFINIBAND_PKEY__ACCESS, &ad);
}

6205 6206 6207 6208 6209 6210 6211 6212 6213 6214 6215 6216 6217 6218 6219 6220 6221 6222 6223 6224 6225 6226 6227
static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
					    u8 port_num)
{
	struct common_audit_data ad;
	int err;
	u32 sid = 0;
	struct ib_security_struct *sec = ib_sec;
	struct lsm_ibendport_audit ibendport;

	err = security_ib_endport_sid(dev_name, port_num, &sid);

	if (err)
		return err;

	ad.type = LSM_AUDIT_DATA_IBENDPORT;
	strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
	ibendport.port = port_num;
	ad.u.ibendport = &ibendport;
	return avc_has_perm(sec->sid, sid,
			    SECCLASS_INFINIBAND_ENDPORT,
			    INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
}

6228 6229 6230
static int selinux_ib_alloc_security(void **ib_sec)
{
	struct ib_security_struct *sec;
6231

6232 6233 6234 6235 6236 6237 6238 6239
	sec = kzalloc(sizeof(*sec), GFP_KERNEL);
	if (!sec)
		return -ENOMEM;
	sec->sid = current_sid();

	*ib_sec = sec;
	return 0;
}
6240

6241 6242 6243 6244
static void selinux_ib_free_security(void *ib_sec)
{
	kfree(ib_sec);
}
6245 6246
#endif

6247
static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6248 6249 6250 6251 6252 6253 6254 6255 6256 6257 6258 6259 6260 6261 6262 6263 6264 6265 6266 6267 6268 6269 6270 6271 6272 6273 6274 6275 6276 6277 6278 6279 6280 6281 6282
	LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
	LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
	LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
	LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),

	LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
	LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
	LSM_HOOK_INIT(capget, selinux_capget),
	LSM_HOOK_INIT(capset, selinux_capset),
	LSM_HOOK_INIT(capable, selinux_capable),
	LSM_HOOK_INIT(quotactl, selinux_quotactl),
	LSM_HOOK_INIT(quota_on, selinux_quota_on),
	LSM_HOOK_INIT(syslog, selinux_syslog),
	LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),

	LSM_HOOK_INIT(netlink_send, selinux_netlink_send),

	LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
	LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
	LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),

	LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
	LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
	LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
	LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
	LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
	LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
	LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
	LSM_HOOK_INIT(sb_mount, selinux_mount),
	LSM_HOOK_INIT(sb_umount, selinux_umount),
	LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
	LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
	LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),

	LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6283
	LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6284 6285 6286 6287 6288 6289 6290 6291 6292 6293 6294 6295 6296 6297 6298 6299 6300 6301 6302 6303 6304 6305 6306 6307 6308 6309

	LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
	LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
	LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
	LSM_HOOK_INIT(inode_create, selinux_inode_create),
	LSM_HOOK_INIT(inode_link, selinux_inode_link),
	LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
	LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
	LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
	LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
	LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
	LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
	LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
	LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
	LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
	LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
	LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
	LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
	LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
	LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
	LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
	LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
	LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
	LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
	LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
	LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
6310
	LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6311
	LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6312 6313 6314 6315 6316 6317 6318 6319 6320 6321 6322 6323 6324 6325 6326 6327

	LSM_HOOK_INIT(file_permission, selinux_file_permission),
	LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
	LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
	LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
	LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
	LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
	LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
	LSM_HOOK_INIT(file_lock, selinux_file_lock),
	LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
	LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
	LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
	LSM_HOOK_INIT(file_receive, selinux_file_receive),

	LSM_HOOK_INIT(file_open, selinux_file_open),

6328
	LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
6329 6330 6331 6332 6333 6334 6335
	LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
	LSM_HOOK_INIT(cred_free, selinux_cred_free),
	LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
	LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
	LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
	LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
	LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6336
	LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6337 6338 6339 6340 6341 6342 6343
	LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
	LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
	LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
	LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
	LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
	LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
	LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6344
	LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
6345 6346 6347 6348 6349 6350 6351 6352 6353 6354 6355 6356 6357 6358 6359 6360 6361 6362 6363 6364 6365 6366 6367 6368 6369 6370 6371 6372 6373 6374 6375 6376 6377 6378 6379 6380 6381 6382 6383 6384 6385 6386
	LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
	LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
	LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
	LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
	LSM_HOOK_INIT(task_kill, selinux_task_kill),
	LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),

	LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
	LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),

	LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
	LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),

	LSM_HOOK_INIT(msg_queue_alloc_security,
			selinux_msg_queue_alloc_security),
	LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
	LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
	LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
	LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
	LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),

	LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
	LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
	LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
	LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
	LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),

	LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
	LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
	LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
	LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
	LSM_HOOK_INIT(sem_semop, selinux_sem_semop),

	LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),

	LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
	LSM_HOOK_INIT(setprocattr, selinux_setprocattr),

	LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
	LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
	LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
	LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
6387
	LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6388 6389 6390 6391 6392 6393 6394 6395 6396 6397 6398 6399 6400 6401 6402 6403 6404 6405 6406 6407 6408 6409 6410 6411 6412 6413 6414 6415 6416 6417 6418 6419 6420 6421 6422 6423 6424 6425 6426 6427 6428 6429
	LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
	LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
	LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),

	LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
	LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),

	LSM_HOOK_INIT(socket_create, selinux_socket_create),
	LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
	LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
	LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
	LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
	LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
	LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
	LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
	LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
	LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
	LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
	LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
	LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
	LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
	LSM_HOOK_INIT(socket_getpeersec_stream,
			selinux_socket_getpeersec_stream),
	LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
	LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
	LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
	LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
	LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
	LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
	LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
	LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
	LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
	LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
	LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
	LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
	LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
	LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
	LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
	LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
	LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
	LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
	LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
6430
#ifdef CONFIG_SECURITY_INFINIBAND
6431
	LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
6432 6433
	LSM_HOOK_INIT(ib_endport_manage_subnet,
		      selinux_ib_endport_manage_subnet),
6434 6435 6436
	LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
	LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
#endif
6437
#ifdef CONFIG_SECURITY_NETWORK_XFRM
6438 6439 6440 6441 6442 6443 6444 6445 6446 6447 6448 6449 6450
	LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
	LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
	LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
	LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
	LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
	LSM_HOOK_INIT(xfrm_state_alloc_acquire,
			selinux_xfrm_state_alloc_acquire),
	LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
	LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
	LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
	LSM_HOOK_INIT(xfrm_state_pol_flow_match,
			selinux_xfrm_state_pol_flow_match),
	LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
L
Linus Torvalds 已提交
6451
#endif
6452 6453

#ifdef CONFIG_KEYS
6454 6455 6456 6457
	LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
	LSM_HOOK_INIT(key_free, selinux_key_free),
	LSM_HOOK_INIT(key_permission, selinux_key_permission),
	LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
6458
#endif
6459 6460

#ifdef CONFIG_AUDIT
6461 6462 6463 6464
	LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
	LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
	LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
	LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
6465
#endif
L
Linus Torvalds 已提交
6466 6467 6468 6469
};

static __init int selinux_init(void)
{
C
Casey Schaufler 已提交
6470
	if (!security_module_enable("selinux")) {
6471 6472 6473 6474
		selinux_enabled = 0;
		return 0;
	}

L
Linus Torvalds 已提交
6475 6476 6477 6478 6479 6480 6481 6482
	if (!selinux_enabled) {
		printk(KERN_INFO "SELinux:  Disabled at boot.\n");
		return 0;
	}

	printk(KERN_INFO "SELinux:  Initializing.\n");

	/* Set the security state for the initial task. */
D
David Howells 已提交
6483
	cred_init_security();
L
Linus Torvalds 已提交
6484

6485 6486
	default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);

6487 6488
	sel_inode_cache = kmem_cache_create("selinux_inode_security",
					    sizeof(struct inode_security_struct),
6489
					    0, SLAB_PANIC, NULL);
6490 6491 6492
	file_security_cache = kmem_cache_create("selinux_file_security",
					    sizeof(struct file_security_struct),
					    0, SLAB_PANIC, NULL);
L
Linus Torvalds 已提交
6493 6494
	avc_init();

6495
	security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
L
Linus Torvalds 已提交
6496

6497 6498 6499
	if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
		panic("SELinux: Unable to register AVC netcache callback\n");

6500 6501 6502
	if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
		panic("SELinux: Unable to register AVC LSM notifier callback\n");

6503
	if (selinux_enforcing)
6504
		printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
6505
	else
6506
		printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
6507

L
Linus Torvalds 已提交
6508 6509 6510
	return 0;
}

6511 6512 6513 6514 6515
static void delayed_superblock_init(struct super_block *sb, void *unused)
{
	superblock_doinit(sb, NULL);
}

L
Linus Torvalds 已提交
6516 6517
void selinux_complete_init(void)
{
6518
	printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
L
Linus Torvalds 已提交
6519 6520

	/* Set up any superblocks initialized prior to the policy load. */
6521
	printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
6522
	iterate_supers(delayed_superblock_init, NULL);
L
Linus Torvalds 已提交
6523 6524 6525 6526 6527 6528
}

/* SELinux requires early initialization in order to label
   all processes and objects when they are created. */
security_initcall(selinux_init);

6529
#if defined(CONFIG_NETFILTER)
L
Linus Torvalds 已提交
6530

6531
static const struct nf_hook_ops selinux_nf_ops[] = {
6532 6533
	{
		.hook =		selinux_ipv4_postroute,
6534
		.pf =		NFPROTO_IPV4,
6535 6536 6537 6538 6539
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv4_forward,
6540
		.pf =		NFPROTO_IPV4,
6541 6542
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6543 6544 6545
	},
	{
		.hook =		selinux_ipv4_output,
6546
		.pf =		NFPROTO_IPV4,
6547 6548
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP_PRI_SELINUX_FIRST,
6549
	},
6550
#if IS_ENABLED(CONFIG_IPV6)
6551 6552
	{
		.hook =		selinux_ipv6_postroute,
6553
		.pf =		NFPROTO_IPV6,
6554 6555 6556 6557 6558
		.hooknum =	NF_INET_POST_ROUTING,
		.priority =	NF_IP6_PRI_SELINUX_LAST,
	},
	{
		.hook =		selinux_ipv6_forward,
6559
		.pf =		NFPROTO_IPV6,
6560 6561
		.hooknum =	NF_INET_FORWARD,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
6562
	},
6563 6564 6565 6566 6567 6568
	{
		.hook =		selinux_ipv6_output,
		.pf =		NFPROTO_IPV6,
		.hooknum =	NF_INET_LOCAL_OUT,
		.priority =	NF_IP6_PRI_SELINUX_FIRST,
	},
L
Linus Torvalds 已提交
6569
#endif	/* IPV6 */
6570
};
L
Linus Torvalds 已提交
6571

6572 6573 6574 6575 6576 6577 6578 6579 6580 6581 6582 6583 6584 6585 6586 6587 6588
static int __net_init selinux_nf_register(struct net *net)
{
	return nf_register_net_hooks(net, selinux_nf_ops,
				     ARRAY_SIZE(selinux_nf_ops));
}

static void __net_exit selinux_nf_unregister(struct net *net)
{
	nf_unregister_net_hooks(net, selinux_nf_ops,
				ARRAY_SIZE(selinux_nf_ops));
}

static struct pernet_operations selinux_net_ops = {
	.init = selinux_nf_register,
	.exit = selinux_nf_unregister,
};

L
Linus Torvalds 已提交
6589 6590
static int __init selinux_nf_ip_init(void)
{
6591
	int err;
L
Linus Torvalds 已提交
6592 6593

	if (!selinux_enabled)
6594
		return 0;
6595 6596 6597

	printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");

6598
	err = register_pernet_subsys(&selinux_net_ops);
6599
	if (err)
6600
		panic("SELinux: register_pernet_subsys: error %d\n", err);
L
Linus Torvalds 已提交
6601

6602
	return 0;
L
Linus Torvalds 已提交
6603 6604 6605 6606 6607 6608
}
__initcall(selinux_nf_ip_init);

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
static void selinux_nf_ip_exit(void)
{
6609
	printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
L
Linus Torvalds 已提交
6610

6611
	unregister_pernet_subsys(&selinux_net_ops);
L
Linus Torvalds 已提交
6612 6613 6614
}
#endif

6615
#else /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
6616 6617 6618 6619 6620

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
#define selinux_nf_ip_exit()
#endif

6621
#endif /* CONFIG_NETFILTER */
L
Linus Torvalds 已提交
6622 6623

#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6624 6625
static int selinux_disabled;

L
Linus Torvalds 已提交
6626 6627 6628 6629 6630 6631 6632 6633 6634 6635 6636 6637 6638 6639 6640
int selinux_disable(void)
{
	if (ss_initialized) {
		/* Not permitted after initial policy load. */
		return -EINVAL;
	}

	if (selinux_disabled) {
		/* Only do this once. */
		return -EINVAL;
	}

	printk(KERN_INFO "SELinux:  Disabled at runtime.\n");

	selinux_disabled = 1;
6641
	selinux_enabled = 0;
L
Linus Torvalds 已提交
6642

C
Casey Schaufler 已提交
6643
	security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
L
Linus Torvalds 已提交
6644

6645 6646 6647
	/* Try to destroy the avc node cache */
	avc_disable();

L
Linus Torvalds 已提交
6648 6649 6650 6651 6652 6653 6654 6655 6656
	/* Unregister netfilter hooks. */
	selinux_nf_ip_exit();

	/* Unregister selinuxfs. */
	exit_sel_fs();

	return 0;
}
#endif