auditsc.c 71.8 KB
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/* auditsc.c -- System-call auditing support
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 * Handles all system-call specific auditing features.
 *
 * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
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 * Copyright 2005 Hewlett-Packard Development Company, L.P.
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 * Copyright (C) 2005, 2006 IBM Corporation
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 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Written by Rickard E. (Rik) Faith <faith@redhat.com>
 *
 * Many of the ideas implemented here are from Stephen C. Tweedie,
 * especially the idea of avoiding a copy by using getname.
 *
 * The method for actual interception of syscall entry and exit (not in
 * this file -- see entry.S) is based on a GPL'd patch written by
 * okir@suse.de and Copyright 2003 SuSE Linux AG.
 *
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 * POSIX message queue support added by George Wilson <ltcgcw@us.ibm.com>,
 * 2006.
 *
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 * The support of additional filter rules compares (>, <, >=, <=) was
 * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005.
 *
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 * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional
 * filesystem information.
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 *
 * Subject and object context labeling support added by <danjones@us.ibm.com>
 * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance.
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 */

#include <linux/init.h>
#include <asm/types.h>
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#include <linux/atomic.h>
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#include <linux/fs.h>
#include <linux/namei.h>
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#include <linux/mm.h>
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#include <linux/export.h>
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#include <linux/slab.h>
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#include <linux/mount.h>
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#include <linux/socket.h>
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#include <linux/mqueue.h>
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#include <linux/audit.h>
#include <linux/personality.h>
#include <linux/time.h>
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#include <linux/netlink.h>
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#include <linux/compiler.h>
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#include <asm/unistd.h>
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#include <linux/security.h>
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#include <linux/list.h>
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#include <linux/tty.h>
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#include <linux/binfmts.h>
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#include <linux/highmem.h>
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#include <linux/syscalls.h>
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#include <linux/capability.h>
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#include <linux/fs_struct.h>
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#include <linux/compat.h>
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#include "audit.h"
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/* flags stating the success for a syscall */
#define AUDITSC_INVALID 0
#define AUDITSC_SUCCESS 1
#define AUDITSC_FAILURE 2

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/* AUDIT_NAMES is the number of slots we reserve in the audit_context
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 * for saving names from getname().  If we get more names we will allocate
 * a name dynamically and also add those to the list anchored by names_list. */
#define AUDIT_NAMES	5
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/* no execve audit message should be longer than this (userspace limits) */
#define MAX_EXECVE_AUDIT_LEN 7500

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/* number of audit rules */
int audit_n_rules;

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/* determines whether we collect data for signals sent */
int audit_signals;

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struct audit_cap_data {
	kernel_cap_t		permitted;
	kernel_cap_t		inheritable;
	union {
		unsigned int	fE;		/* effective bit of a file capability */
		kernel_cap_t	effective;	/* effective set of a process */
	};
};

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/* When fs/namei.c:getname() is called, we store the pointer in name and
 * we don't let putname() free it (instead we free all of the saved
 * pointers at syscall exit time).
 *
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 * Further, in fs/namei.c:path_lookup() we store the inode and device.
 */
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struct audit_names {
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	struct list_head	list;		/* audit_context->names_list */
	struct filename	*name;
	unsigned long		ino;
	dev_t			dev;
	umode_t			mode;
	kuid_t			uid;
	kgid_t			gid;
	dev_t			rdev;
	u32			osid;
	struct audit_cap_data	 fcap;
	unsigned int		fcap_ver;
	int			name_len;	/* number of name's characters to log */
	unsigned char		type;		/* record type */
	bool			name_put;	/* call __putname() for this name */
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	/*
	 * This was an allocated audit_names and not from the array of
	 * names allocated in the task audit context.  Thus this name
	 * should be freed on syscall exit
	 */
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	bool			should_free;
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};

struct audit_aux_data {
	struct audit_aux_data	*next;
	int			type;
};

#define AUDIT_AUX_IPCPERM	0

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/* Number of target pids per aux struct. */
#define AUDIT_AUX_PIDS	16

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struct audit_aux_data_execve {
	struct audit_aux_data	d;
	int argc;
	int envc;
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	struct mm_struct *mm;
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};

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struct audit_aux_data_pids {
	struct audit_aux_data	d;
	pid_t			target_pid[AUDIT_AUX_PIDS];
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	kuid_t			target_auid[AUDIT_AUX_PIDS];
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	kuid_t			target_uid[AUDIT_AUX_PIDS];
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	unsigned int		target_sessionid[AUDIT_AUX_PIDS];
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	u32			target_sid[AUDIT_AUX_PIDS];
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	char 			target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
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	int			pid_count;
};

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struct audit_aux_data_bprm_fcaps {
	struct audit_aux_data	d;
	struct audit_cap_data	fcap;
	unsigned int		fcap_ver;
	struct audit_cap_data	old_pcap;
	struct audit_cap_data	new_pcap;
};

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struct audit_aux_data_capset {
	struct audit_aux_data	d;
	pid_t			pid;
	struct audit_cap_data	cap;
};

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struct audit_tree_refs {
	struct audit_tree_refs *next;
	struct audit_chunk *c[31];
};

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/* The per-task audit context. */
struct audit_context {
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	int		    dummy;	/* must be the first element */
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	int		    in_syscall;	/* 1 if task is in a syscall */
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	enum audit_state    state, current_state;
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	unsigned int	    serial;     /* serial number for record */
	int		    major;      /* syscall number */
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	struct timespec	    ctime;      /* time of syscall entry */
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	unsigned long	    argv[4];    /* syscall arguments */
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	long		    return_code;/* syscall return code */
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	u64		    prio;
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	int		    return_valid; /* return code is valid */
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	/*
	 * The names_list is the list of all audit_names collected during this
	 * syscall.  The first AUDIT_NAMES entries in the names_list will
	 * actually be from the preallocated_names array for performance
	 * reasons.  Except during allocation they should never be referenced
	 * through the preallocated_names array and should only be found/used
	 * by running the names_list.
	 */
	struct audit_names  preallocated_names[AUDIT_NAMES];
	int		    name_count; /* total records in names_list */
	struct list_head    names_list;	/* anchor for struct audit_names->list */
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	char *		    filterkey;	/* key for rule that triggered record */
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	struct path	    pwd;
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	struct audit_aux_data *aux;
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	struct audit_aux_data *aux_pids;
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	struct sockaddr_storage *sockaddr;
	size_t sockaddr_len;
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				/* Save things to print about task_struct */
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	pid_t		    pid, ppid;
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	kuid_t		    uid, euid, suid, fsuid;
	kgid_t		    gid, egid, sgid, fsgid;
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	unsigned long	    personality;
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	int		    arch;
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	pid_t		    target_pid;
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	kuid_t		    target_auid;
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	kuid_t		    target_uid;
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	unsigned int	    target_sessionid;
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	u32		    target_sid;
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	char		    target_comm[TASK_COMM_LEN];
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	struct audit_tree_refs *trees, *first_trees;
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	struct list_head killed_trees;
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	int tree_count;
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	int type;
	union {
		struct {
			int nargs;
			long args[6];
		} socketcall;
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		struct {
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			kuid_t			uid;
			kgid_t			gid;
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			umode_t			mode;
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			u32			osid;
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			int			has_perm;
			uid_t			perm_uid;
			gid_t			perm_gid;
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			umode_t			perm_mode;
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			unsigned long		qbytes;
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		} ipc;
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		struct {
			mqd_t			mqdes;
			struct mq_attr 		mqstat;
		} mq_getsetattr;
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		struct {
			mqd_t			mqdes;
			int			sigev_signo;
		} mq_notify;
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		struct {
			mqd_t			mqdes;
			size_t			msg_len;
			unsigned int		msg_prio;
			struct timespec		abs_timeout;
		} mq_sendrecv;
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		struct {
			int			oflag;
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			umode_t			mode;
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			struct mq_attr		attr;
		} mq_open;
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		struct {
			pid_t			pid;
			struct audit_cap_data	cap;
		} capset;
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		struct {
			int			fd;
			int			flags;
		} mmap;
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	};
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	int fds[2];
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#if AUDIT_DEBUG
	int		    put_count;
	int		    ino_count;
#endif
};

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static inline int open_arg(int flags, int mask)
{
	int n = ACC_MODE(flags);
	if (flags & (O_TRUNC | O_CREAT))
		n |= AUDIT_PERM_WRITE;
	return n & mask;
}

static int audit_match_perm(struct audit_context *ctx, int mask)
{
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	unsigned n;
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	if (unlikely(!ctx))
		return 0;
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	n = ctx->major;
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	switch (audit_classify_syscall(ctx->arch, n)) {
	case 0:	/* native */
		if ((mask & AUDIT_PERM_WRITE) &&
		     audit_match_class(AUDIT_CLASS_WRITE, n))
			return 1;
		if ((mask & AUDIT_PERM_READ) &&
		     audit_match_class(AUDIT_CLASS_READ, n))
			return 1;
		if ((mask & AUDIT_PERM_ATTR) &&
		     audit_match_class(AUDIT_CLASS_CHATTR, n))
			return 1;
		return 0;
	case 1: /* 32bit on biarch */
		if ((mask & AUDIT_PERM_WRITE) &&
		     audit_match_class(AUDIT_CLASS_WRITE_32, n))
			return 1;
		if ((mask & AUDIT_PERM_READ) &&
		     audit_match_class(AUDIT_CLASS_READ_32, n))
			return 1;
		if ((mask & AUDIT_PERM_ATTR) &&
		     audit_match_class(AUDIT_CLASS_CHATTR_32, n))
			return 1;
		return 0;
	case 2: /* open */
		return mask & ACC_MODE(ctx->argv[1]);
	case 3: /* openat */
		return mask & ACC_MODE(ctx->argv[2]);
	case 4: /* socketcall */
		return ((mask & AUDIT_PERM_WRITE) && ctx->argv[0] == SYS_BIND);
	case 5: /* execve */
		return mask & AUDIT_PERM_EXEC;
	default:
		return 0;
	}
}

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static int audit_match_filetype(struct audit_context *ctx, int val)
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{
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	struct audit_names *n;
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	umode_t mode = (umode_t)val;
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	if (unlikely(!ctx))
		return 0;

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	list_for_each_entry(n, &ctx->names_list, list) {
		if ((n->ino != -1) &&
		    ((n->mode & S_IFMT) == mode))
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			return 1;
	}
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	return 0;
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}

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/*
 * We keep a linked list of fixed-sized (31 pointer) arrays of audit_chunk *;
 * ->first_trees points to its beginning, ->trees - to the current end of data.
 * ->tree_count is the number of free entries in array pointed to by ->trees.
 * Original condition is (NULL, NULL, 0); as soon as it grows we never revert to NULL,
 * "empty" becomes (p, p, 31) afterwards.  We don't shrink the list (and seriously,
 * it's going to remain 1-element for almost any setup) until we free context itself.
 * References in it _are_ dropped - at the same time we free/drop aux stuff.
 */

#ifdef CONFIG_AUDIT_TREE
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static void audit_set_auditable(struct audit_context *ctx)
{
	if (!ctx->prio) {
		ctx->prio = 1;
		ctx->current_state = AUDIT_RECORD_CONTEXT;
	}
}

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static int put_tree_ref(struct audit_context *ctx, struct audit_chunk *chunk)
{
	struct audit_tree_refs *p = ctx->trees;
	int left = ctx->tree_count;
	if (likely(left)) {
		p->c[--left] = chunk;
		ctx->tree_count = left;
		return 1;
	}
	if (!p)
		return 0;
	p = p->next;
	if (p) {
		p->c[30] = chunk;
		ctx->trees = p;
		ctx->tree_count = 30;
		return 1;
	}
	return 0;
}

static int grow_tree_refs(struct audit_context *ctx)
{
	struct audit_tree_refs *p = ctx->trees;
	ctx->trees = kzalloc(sizeof(struct audit_tree_refs), GFP_KERNEL);
	if (!ctx->trees) {
		ctx->trees = p;
		return 0;
	}
	if (p)
		p->next = ctx->trees;
	else
		ctx->first_trees = ctx->trees;
	ctx->tree_count = 31;
	return 1;
}
#endif

static void unroll_tree_refs(struct audit_context *ctx,
		      struct audit_tree_refs *p, int count)
{
#ifdef CONFIG_AUDIT_TREE
	struct audit_tree_refs *q;
	int n;
	if (!p) {
		/* we started with empty chain */
		p = ctx->first_trees;
		count = 31;
		/* if the very first allocation has failed, nothing to do */
		if (!p)
			return;
	}
	n = count;
	for (q = p; q != ctx->trees; q = q->next, n = 31) {
		while (n--) {
			audit_put_chunk(q->c[n]);
			q->c[n] = NULL;
		}
	}
	while (n-- > ctx->tree_count) {
		audit_put_chunk(q->c[n]);
		q->c[n] = NULL;
	}
	ctx->trees = p;
	ctx->tree_count = count;
#endif
}

static void free_tree_refs(struct audit_context *ctx)
{
	struct audit_tree_refs *p, *q;
	for (p = ctx->first_trees; p; p = q) {
		q = p->next;
		kfree(p);
	}
}

static int match_tree_refs(struct audit_context *ctx, struct audit_tree *tree)
{
#ifdef CONFIG_AUDIT_TREE
	struct audit_tree_refs *p;
	int n;
	if (!tree)
		return 0;
	/* full ones */
	for (p = ctx->first_trees; p != ctx->trees; p = p->next) {
		for (n = 0; n < 31; n++)
			if (audit_tree_match(p->c[n], tree))
				return 1;
	}
	/* partial */
	if (p) {
		for (n = ctx->tree_count; n < 31; n++)
			if (audit_tree_match(p->c[n], tree))
				return 1;
	}
#endif
	return 0;
}

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static int audit_compare_uid(kuid_t uid,
			     struct audit_names *name,
			     struct audit_field *f,
			     struct audit_context *ctx)
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{
	struct audit_names *n;
	int rc;
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	if (name) {
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		rc = audit_uid_comparator(uid, f->op, name->uid);
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		if (rc)
			return rc;
	}
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	if (ctx) {
		list_for_each_entry(n, &ctx->names_list, list) {
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			rc = audit_uid_comparator(uid, f->op, n->uid);
			if (rc)
				return rc;
		}
	}
	return 0;
}
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static int audit_compare_gid(kgid_t gid,
			     struct audit_names *name,
			     struct audit_field *f,
			     struct audit_context *ctx)
{
	struct audit_names *n;
	int rc;
 
	if (name) {
		rc = audit_gid_comparator(gid, f->op, name->gid);
		if (rc)
			return rc;
	}
 
	if (ctx) {
		list_for_each_entry(n, &ctx->names_list, list) {
			rc = audit_gid_comparator(gid, f->op, n->gid);
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			if (rc)
				return rc;
		}
	}
	return 0;
}

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static int audit_field_compare(struct task_struct *tsk,
			       const struct cred *cred,
			       struct audit_field *f,
			       struct audit_context *ctx,
			       struct audit_names *name)
{
	switch (f->val) {
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	/* process to file object comparisons */
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	case AUDIT_COMPARE_UID_TO_OBJ_UID:
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		return audit_compare_uid(cred->uid, name, f, ctx);
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	case AUDIT_COMPARE_GID_TO_OBJ_GID:
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		return audit_compare_gid(cred->gid, name, f, ctx);
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	case AUDIT_COMPARE_EUID_TO_OBJ_UID:
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		return audit_compare_uid(cred->euid, name, f, ctx);
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	case AUDIT_COMPARE_EGID_TO_OBJ_GID:
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		return audit_compare_gid(cred->egid, name, f, ctx);
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	case AUDIT_COMPARE_AUID_TO_OBJ_UID:
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		return audit_compare_uid(tsk->loginuid, name, f, ctx);
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	case AUDIT_COMPARE_SUID_TO_OBJ_UID:
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		return audit_compare_uid(cred->suid, name, f, ctx);
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	case AUDIT_COMPARE_SGID_TO_OBJ_GID:
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		return audit_compare_gid(cred->sgid, name, f, ctx);
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	case AUDIT_COMPARE_FSUID_TO_OBJ_UID:
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		return audit_compare_uid(cred->fsuid, name, f, ctx);
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	case AUDIT_COMPARE_FSGID_TO_OBJ_GID:
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		return audit_compare_gid(cred->fsgid, name, f, ctx);
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	/* uid comparisons */
	case AUDIT_COMPARE_UID_TO_AUID:
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		return audit_uid_comparator(cred->uid, f->op, tsk->loginuid);
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	case AUDIT_COMPARE_UID_TO_EUID:
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		return audit_uid_comparator(cred->uid, f->op, cred->euid);
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	case AUDIT_COMPARE_UID_TO_SUID:
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		return audit_uid_comparator(cred->uid, f->op, cred->suid);
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	case AUDIT_COMPARE_UID_TO_FSUID:
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		return audit_uid_comparator(cred->uid, f->op, cred->fsuid);
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	/* auid comparisons */
	case AUDIT_COMPARE_AUID_TO_EUID:
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		return audit_uid_comparator(tsk->loginuid, f->op, cred->euid);
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	case AUDIT_COMPARE_AUID_TO_SUID:
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		return audit_uid_comparator(tsk->loginuid, f->op, cred->suid);
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	case AUDIT_COMPARE_AUID_TO_FSUID:
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		return audit_uid_comparator(tsk->loginuid, f->op, cred->fsuid);
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	/* euid comparisons */
	case AUDIT_COMPARE_EUID_TO_SUID:
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		return audit_uid_comparator(cred->euid, f->op, cred->suid);
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	case AUDIT_COMPARE_EUID_TO_FSUID:
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		return audit_uid_comparator(cred->euid, f->op, cred->fsuid);
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	/* suid comparisons */
	case AUDIT_COMPARE_SUID_TO_FSUID:
562
		return audit_uid_comparator(cred->suid, f->op, cred->fsuid);
563 564
	/* gid comparisons */
	case AUDIT_COMPARE_GID_TO_EGID:
565
		return audit_gid_comparator(cred->gid, f->op, cred->egid);
566
	case AUDIT_COMPARE_GID_TO_SGID:
567
		return audit_gid_comparator(cred->gid, f->op, cred->sgid);
568
	case AUDIT_COMPARE_GID_TO_FSGID:
569
		return audit_gid_comparator(cred->gid, f->op, cred->fsgid);
570 571
	/* egid comparisons */
	case AUDIT_COMPARE_EGID_TO_SGID:
572
		return audit_gid_comparator(cred->egid, f->op, cred->sgid);
573
	case AUDIT_COMPARE_EGID_TO_FSGID:
574
		return audit_gid_comparator(cred->egid, f->op, cred->fsgid);
575 576
	/* sgid comparison */
	case AUDIT_COMPARE_SGID_TO_FSGID:
577
		return audit_gid_comparator(cred->sgid, f->op, cred->fsgid);
578 579 580 581 582 583 584
	default:
		WARN(1, "Missing AUDIT_COMPARE define.  Report as a bug\n");
		return 0;
	}
	return 0;
}

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/* Determine if any context name data matches a rule's watch data */
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/* Compare a task_struct with an audit_rule.  Return 1 on match, 0
587 588 589 590 591 592
 * otherwise.
 *
 * If task_creation is true, this is an explicit indication that we are
 * filtering a task rule at task creation time.  This and tsk == current are
 * the only situations where tsk->cred may be accessed without an rcu read lock.
 */
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static int audit_filter_rules(struct task_struct *tsk,
594
			      struct audit_krule *rule,
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595
			      struct audit_context *ctx,
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			      struct audit_names *name,
597 598
			      enum audit_state *state,
			      bool task_creation)
L
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599
{
600
	const struct cred *cred;
601
	int i, need_sid = 1;
602 603
	u32 sid;

604 605
	cred = rcu_dereference_check(tsk->cred, tsk == current || task_creation);

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606
	for (i = 0; i < rule->field_count; i++) {
607
		struct audit_field *f = &rule->fields[i];
608
		struct audit_names *n;
L
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609 610
		int result = 0;

611
		switch (f->type) {
L
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612
		case AUDIT_PID:
613
			result = audit_comparator(tsk->pid, f->op, f->val);
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614
			break;
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615
		case AUDIT_PPID:
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616 617 618
			if (ctx) {
				if (!ctx->ppid)
					ctx->ppid = sys_getppid();
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				result = audit_comparator(ctx->ppid, f->op, f->val);
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620
			}
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621
			break;
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		case AUDIT_UID:
623
			result = audit_uid_comparator(cred->uid, f->op, f->uid);
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			break;
		case AUDIT_EUID:
626
			result = audit_uid_comparator(cred->euid, f->op, f->uid);
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			break;
		case AUDIT_SUID:
629
			result = audit_uid_comparator(cred->suid, f->op, f->uid);
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			break;
		case AUDIT_FSUID:
632
			result = audit_uid_comparator(cred->fsuid, f->op, f->uid);
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			break;
		case AUDIT_GID:
635
			result = audit_gid_comparator(cred->gid, f->op, f->gid);
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636 637
			break;
		case AUDIT_EGID:
638
			result = audit_gid_comparator(cred->egid, f->op, f->gid);
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639 640
			break;
		case AUDIT_SGID:
641
			result = audit_gid_comparator(cred->sgid, f->op, f->gid);
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			break;
		case AUDIT_FSGID:
644
			result = audit_gid_comparator(cred->fsgid, f->op, f->gid);
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645 646
			break;
		case AUDIT_PERS:
647
			result = audit_comparator(tsk->personality, f->op, f->val);
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648
			break;
649
		case AUDIT_ARCH:
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650
			if (ctx)
651
				result = audit_comparator(ctx->arch, f->op, f->val);
652
			break;
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653 654 655

		case AUDIT_EXIT:
			if (ctx && ctx->return_valid)
656
				result = audit_comparator(ctx->return_code, f->op, f->val);
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657 658
			break;
		case AUDIT_SUCCESS:
659
			if (ctx && ctx->return_valid) {
660 661
				if (f->val)
					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
662
				else
663
					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
664
			}
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			break;
		case AUDIT_DEVMAJOR:
667 668 669 670 671
			if (name) {
				if (audit_comparator(MAJOR(name->dev), f->op, f->val) ||
				    audit_comparator(MAJOR(name->rdev), f->op, f->val))
					++result;
			} else if (ctx) {
672
				list_for_each_entry(n, &ctx->names_list, list) {
673 674
					if (audit_comparator(MAJOR(n->dev), f->op, f->val) ||
					    audit_comparator(MAJOR(n->rdev), f->op, f->val)) {
L
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675 676 677 678 679 680 681
						++result;
						break;
					}
				}
			}
			break;
		case AUDIT_DEVMINOR:
682 683 684 685 686
			if (name) {
				if (audit_comparator(MINOR(name->dev), f->op, f->val) ||
				    audit_comparator(MINOR(name->rdev), f->op, f->val))
					++result;
			} else if (ctx) {
687
				list_for_each_entry(n, &ctx->names_list, list) {
688 689
					if (audit_comparator(MINOR(n->dev), f->op, f->val) ||
					    audit_comparator(MINOR(n->rdev), f->op, f->val)) {
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						++result;
						break;
					}
				}
			}
			break;
		case AUDIT_INODE:
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			if (name)
698
				result = (name->ino == f->val);
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699
			else if (ctx) {
700 701
				list_for_each_entry(n, &ctx->names_list, list) {
					if (audit_comparator(n->ino, f->op, f->val)) {
L
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702 703 704 705 706 707
						++result;
						break;
					}
				}
			}
			break;
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		case AUDIT_OBJ_UID:
			if (name) {
710
				result = audit_uid_comparator(name->uid, f->op, f->uid);
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711 712
			} else if (ctx) {
				list_for_each_entry(n, &ctx->names_list, list) {
713
					if (audit_uid_comparator(n->uid, f->op, f->uid)) {
E
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714 715 716 717 718 719
						++result;
						break;
					}
				}
			}
			break;
720 721
		case AUDIT_OBJ_GID:
			if (name) {
722
				result = audit_gid_comparator(name->gid, f->op, f->gid);
723 724
			} else if (ctx) {
				list_for_each_entry(n, &ctx->names_list, list) {
725
					if (audit_gid_comparator(n->gid, f->op, f->gid)) {
726 727 728 729 730 731
						++result;
						break;
					}
				}
			}
			break;
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		case AUDIT_WATCH:
733 734
			if (name)
				result = audit_watch_compare(rule->watch, name->ino, name->dev);
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			break;
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736 737 738 739
		case AUDIT_DIR:
			if (ctx)
				result = match_tree_refs(ctx, rule->tree);
			break;
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740 741 742
		case AUDIT_LOGINUID:
			result = 0;
			if (ctx)
743
				result = audit_uid_comparator(tsk->loginuid, f->op, f->uid);
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			break;
745 746 747 748 749
		case AUDIT_SUBJ_USER:
		case AUDIT_SUBJ_ROLE:
		case AUDIT_SUBJ_TYPE:
		case AUDIT_SUBJ_SEN:
		case AUDIT_SUBJ_CLR:
750 751 752 753 754
			/* NOTE: this may return negative values indicating
			   a temporary error.  We simply treat this as a
			   match for now to avoid losing information that
			   may be wanted.   An error message will also be
			   logged upon error */
755
			if (f->lsm_rule) {
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Steve Grubb 已提交
756
				if (need_sid) {
757
					security_task_getsecid(tsk, &sid);
S
Steve Grubb 已提交
758 759
					need_sid = 0;
				}
760
				result = security_audit_rule_match(sid, f->type,
761
				                                  f->op,
762
				                                  f->lsm_rule,
763
				                                  ctx);
S
Steve Grubb 已提交
764
			}
765
			break;
766 767 768 769 770 771 772
		case AUDIT_OBJ_USER:
		case AUDIT_OBJ_ROLE:
		case AUDIT_OBJ_TYPE:
		case AUDIT_OBJ_LEV_LOW:
		case AUDIT_OBJ_LEV_HIGH:
			/* The above note for AUDIT_SUBJ_USER...AUDIT_SUBJ_CLR
			   also applies here */
773
			if (f->lsm_rule) {
774 775
				/* Find files that match */
				if (name) {
776
					result = security_audit_rule_match(
777
					           name->osid, f->type, f->op,
778
					           f->lsm_rule, ctx);
779
				} else if (ctx) {
780 781 782 783
					list_for_each_entry(n, &ctx->names_list, list) {
						if (security_audit_rule_match(n->osid, f->type,
									      f->op, f->lsm_rule,
									      ctx)) {
784 785 786 787 788 789
							++result;
							break;
						}
					}
				}
				/* Find ipc objects that match */
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790 791 792 793 794 795
				if (!ctx || ctx->type != AUDIT_IPC)
					break;
				if (security_audit_rule_match(ctx->ipc.osid,
							      f->type, f->op,
							      f->lsm_rule, ctx))
					++result;
796 797
			}
			break;
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798 799 800 801 802
		case AUDIT_ARG0:
		case AUDIT_ARG1:
		case AUDIT_ARG2:
		case AUDIT_ARG3:
			if (ctx)
803
				result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
L
Linus Torvalds 已提交
804
			break;
A
Amy Griffis 已提交
805 806 807 808
		case AUDIT_FILTERKEY:
			/* ignore this field for filtering */
			result = 1;
			break;
A
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809 810 811
		case AUDIT_PERM:
			result = audit_match_perm(ctx, f->val);
			break;
A
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812 813 814
		case AUDIT_FILETYPE:
			result = audit_match_filetype(ctx, f->val);
			break;
815 816 817
		case AUDIT_FIELD_COMPARE:
			result = audit_field_compare(tsk, cred, f, ctx, name);
			break;
L
Linus Torvalds 已提交
818
		}
819
		if (!result)
L
Linus Torvalds 已提交
820 821
			return 0;
	}
822 823 824 825 826 827 828 829 830 831

	if (ctx) {
		if (rule->prio <= ctx->prio)
			return 0;
		if (rule->filterkey) {
			kfree(ctx->filterkey);
			ctx->filterkey = kstrdup(rule->filterkey, GFP_ATOMIC);
		}
		ctx->prio = rule->prio;
	}
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832 833 834 835 836 837 838 839 840 841 842
	switch (rule->action) {
	case AUDIT_NEVER:    *state = AUDIT_DISABLED;	    break;
	case AUDIT_ALWAYS:   *state = AUDIT_RECORD_CONTEXT; break;
	}
	return 1;
}

/* At process creation time, we can determine if system-call auditing is
 * completely disabled for this task.  Since we only have the task
 * structure at this point, we can only check uid and gid.
 */
843
static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
L
Linus Torvalds 已提交
844 845 846 847 848
{
	struct audit_entry *e;
	enum audit_state   state;

	rcu_read_lock();
849
	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
850 851
		if (audit_filter_rules(tsk, &e->rule, NULL, NULL,
				       &state, true)) {
852 853
			if (state == AUDIT_RECORD_CONTEXT)
				*key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
L
Linus Torvalds 已提交
854 855 856 857 858 859 860 861 862 863
			rcu_read_unlock();
			return state;
		}
	}
	rcu_read_unlock();
	return AUDIT_BUILD_CONTEXT;
}

/* At syscall entry and exit time, this filter is called if the
 * audit_state is not low enough that auditing cannot take place, but is
S
Steve Grubb 已提交
864
 * also not high enough that we already know we have to write an audit
865
 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
L
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866 867 868 869 870 871
 */
static enum audit_state audit_filter_syscall(struct task_struct *tsk,
					     struct audit_context *ctx,
					     struct list_head *list)
{
	struct audit_entry *e;
872
	enum audit_state state;
L
Linus Torvalds 已提交
873

874
	if (audit_pid && tsk->tgid == audit_pid)
875 876
		return AUDIT_DISABLED;

L
Linus Torvalds 已提交
877
	rcu_read_lock();
878
	if (!list_empty(list)) {
879 880 881 882
		int word = AUDIT_WORD(ctx->major);
		int bit  = AUDIT_BIT(ctx->major);

		list_for_each_entry_rcu(e, list, list) {
A
Amy Griffis 已提交
883 884
			if ((e->rule.mask[word] & bit) == bit &&
			    audit_filter_rules(tsk, &e->rule, ctx, NULL,
885
					       &state, false)) {
A
Amy Griffis 已提交
886
				rcu_read_unlock();
887
				ctx->current_state = state;
A
Amy Griffis 已提交
888 889 890 891 892 893 894 895
				return state;
			}
		}
	}
	rcu_read_unlock();
	return AUDIT_BUILD_CONTEXT;
}

896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926
/*
 * Given an audit_name check the inode hash table to see if they match.
 * Called holding the rcu read lock to protect the use of audit_inode_hash
 */
static int audit_filter_inode_name(struct task_struct *tsk,
				   struct audit_names *n,
				   struct audit_context *ctx) {
	int word, bit;
	int h = audit_hash_ino((u32)n->ino);
	struct list_head *list = &audit_inode_hash[h];
	struct audit_entry *e;
	enum audit_state state;

	word = AUDIT_WORD(ctx->major);
	bit  = AUDIT_BIT(ctx->major);

	if (list_empty(list))
		return 0;

	list_for_each_entry_rcu(e, list, list) {
		if ((e->rule.mask[word] & bit) == bit &&
		    audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) {
			ctx->current_state = state;
			return 1;
		}
	}

	return 0;
}

/* At syscall exit time, this filter is called if any audit_names have been
A
Amy Griffis 已提交
927
 * collected during syscall processing.  We only check rules in sublists at hash
928
 * buckets applicable to the inode numbers in audit_names.
A
Amy Griffis 已提交
929 930
 * Regarding audit_state, same rules apply as for audit_filter_syscall().
 */
931
void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
A
Amy Griffis 已提交
932
{
933
	struct audit_names *n;
A
Amy Griffis 已提交
934 935

	if (audit_pid && tsk->tgid == audit_pid)
936
		return;
A
Amy Griffis 已提交
937 938 939

	rcu_read_lock();

940 941 942
	list_for_each_entry(n, &ctx->names_list, list) {
		if (audit_filter_inode_name(tsk, n, ctx))
			break;
943 944 945 946
	}
	rcu_read_unlock();
}

L
Linus Torvalds 已提交
947 948
static inline struct audit_context *audit_get_context(struct task_struct *tsk,
						      int return_valid,
949
						      long return_code)
L
Linus Torvalds 已提交
950 951 952
{
	struct audit_context *context = tsk->audit_context;

953
	if (!context)
L
Linus Torvalds 已提交
954 955
		return NULL;
	context->return_valid = return_valid;
E
Eric Paris 已提交
956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973

	/*
	 * we need to fix up the return code in the audit logs if the actual
	 * return codes are later going to be fixed up by the arch specific
	 * signal handlers
	 *
	 * This is actually a test for:
	 * (rc == ERESTARTSYS ) || (rc == ERESTARTNOINTR) ||
	 * (rc == ERESTARTNOHAND) || (rc == ERESTART_RESTARTBLOCK)
	 *
	 * but is faster than a bunch of ||
	 */
	if (unlikely(return_code <= -ERESTARTSYS) &&
	    (return_code >= -ERESTART_RESTARTBLOCK) &&
	    (return_code != -ENOIOCTLCMD))
		context->return_code = -EINTR;
	else
		context->return_code  = return_code;
L
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975 976 977
	if (context->in_syscall && !context->dummy) {
		audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
		audit_filter_inodes(tsk, context);
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	}

	tsk->audit_context = NULL;
	return context;
}

static inline void audit_free_names(struct audit_context *context)
{
986
	struct audit_names *n, *next;
L
Linus Torvalds 已提交
987 988

#if AUDIT_DEBUG == 2
989
	if (context->put_count + context->ino_count != context->name_count) {
990
		printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
L
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		       " name_count=%d put_count=%d"
		       " ino_count=%d [NOT freeing]\n",
993
		       __FILE__, __LINE__,
L
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994 995 996
		       context->serial, context->major, context->in_syscall,
		       context->name_count, context->put_count,
		       context->ino_count);
997
		list_for_each_entry(n, &context->names_list, list) {
L
Linus Torvalds 已提交
998
			printk(KERN_ERR "names[%d] = %p = %s\n", i,
999
			       n->name, n->name->name ?: "(null)");
1000
		}
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1001 1002 1003 1004 1005 1006 1007 1008 1009
		dump_stack();
		return;
	}
#endif
#if AUDIT_DEBUG
	context->put_count  = 0;
	context->ino_count  = 0;
#endif

1010 1011 1012 1013 1014 1015
	list_for_each_entry_safe(n, next, &context->names_list, list) {
		list_del(&n->list);
		if (n->name && n->name_put)
			__putname(n->name);
		if (n->should_free)
			kfree(n);
1016
	}
L
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1017
	context->name_count = 0;
1018 1019 1020
	path_put(&context->pwd);
	context->pwd.dentry = NULL;
	context->pwd.mnt = NULL;
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}

static inline void audit_free_aux(struct audit_context *context)
{
	struct audit_aux_data *aux;

	while ((aux = context->aux)) {
		context->aux = aux->next;
		kfree(aux);
	}
A
Amy Griffis 已提交
1031 1032 1033 1034
	while ((aux = context->aux_pids)) {
		context->aux_pids = aux->next;
		kfree(aux);
	}
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}

static inline void audit_zero_context(struct audit_context *context,
				      enum audit_state state)
{
	memset(context, 0, sizeof(*context));
	context->state      = state;
1042
	context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
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}

static inline struct audit_context *audit_alloc_context(enum audit_state state)
{
	struct audit_context *context;

	if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
		return NULL;
	audit_zero_context(context, state);
A
Al Viro 已提交
1052
	INIT_LIST_HEAD(&context->killed_trees);
1053
	INIT_LIST_HEAD(&context->names_list);
L
Linus Torvalds 已提交
1054 1055 1056
	return context;
}

1057 1058 1059 1060 1061
/**
 * audit_alloc - allocate an audit context block for a task
 * @tsk: task
 *
 * Filter on the task information and allocate a per-task audit context
L
Linus Torvalds 已提交
1062 1063
 * if necessary.  Doing so turns on system call auditing for the
 * specified task.  This is called from copy_process, so no lock is
1064 1065
 * needed.
 */
L
Linus Torvalds 已提交
1066 1067 1068 1069
int audit_alloc(struct task_struct *tsk)
{
	struct audit_context *context;
	enum audit_state     state;
1070
	char *key = NULL;
L
Linus Torvalds 已提交
1071

1072
	if (likely(!audit_ever_enabled))
L
Linus Torvalds 已提交
1073 1074
		return 0; /* Return if not auditing. */

1075
	state = audit_filter_task(tsk, &key);
1076
	if (state == AUDIT_DISABLED)
L
Linus Torvalds 已提交
1077 1078 1079
		return 0;

	if (!(context = audit_alloc_context(state))) {
1080
		kfree(key);
L
Linus Torvalds 已提交
1081 1082 1083
		audit_log_lost("out of memory in audit_alloc");
		return -ENOMEM;
	}
1084
	context->filterkey = key;
L
Linus Torvalds 已提交
1085 1086 1087 1088 1089 1090 1091 1092

	tsk->audit_context  = context;
	set_tsk_thread_flag(tsk, TIF_SYSCALL_AUDIT);
	return 0;
}

static inline void audit_free_context(struct audit_context *context)
{
A
Al Viro 已提交
1093 1094 1095 1096 1097 1098 1099
	audit_free_names(context);
	unroll_tree_refs(context, NULL, 0);
	free_tree_refs(context);
	audit_free_aux(context);
	kfree(context->filterkey);
	kfree(context->sockaddr);
	kfree(context);
L
Linus Torvalds 已提交
1100 1101
}

J
Joy Latten 已提交
1102
void audit_log_task_context(struct audit_buffer *ab)
1103 1104
{
	char *ctx = NULL;
1105 1106 1107 1108
	unsigned len;
	int error;
	u32 sid;

1109
	security_task_getsecid(current, &sid);
1110 1111
	if (!sid)
		return;
1112

1113
	error = security_secid_to_secctx(sid, &ctx, &len);
1114 1115
	if (error) {
		if (error != -EINVAL)
1116 1117 1118 1119 1120
			goto error_path;
		return;
	}

	audit_log_format(ab, " subj=%s", ctx);
1121
	security_release_secctx(ctx, len);
1122
	return;
1123 1124

error_path:
1125
	audit_panic("error in audit_log_task_context");
1126 1127 1128
	return;
}

J
Joy Latten 已提交
1129 1130
EXPORT_SYMBOL(audit_log_task_context);

P
Peter Moody 已提交
1131
void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
1132
{
P
Peter Moody 已提交
1133
	const struct cred *cred;
1134 1135
	char name[sizeof(tsk->comm)];
	struct mm_struct *mm = tsk->mm;
P
Peter Moody 已提交
1136 1137 1138 1139
	char *tty;

	if (!ab)
		return;
1140

1141
	/* tsk == current */
P
Peter Moody 已提交
1142 1143 1144
	cred = current_cred();

	spin_lock_irq(&tsk->sighand->siglock);
A
Alan Cox 已提交
1145
	if (tsk->signal && tsk->signal->tty)
P
Peter Moody 已提交
1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157
		tty = tsk->signal->tty->name;
	else
		tty = "(none)";
	spin_unlock_irq(&tsk->sighand->siglock);


	audit_log_format(ab,
			 " ppid=%ld pid=%d auid=%u uid=%u gid=%u"
			 " euid=%u suid=%u fsuid=%u"
			 " egid=%u sgid=%u fsgid=%u ses=%u tty=%s",
			 sys_getppid(),
			 tsk->pid,
1158 1159 1160 1161 1162 1163 1164 1165 1166
			 from_kuid(&init_user_ns, tsk->loginuid),
			 from_kuid(&init_user_ns, cred->uid),
			 from_kgid(&init_user_ns, cred->gid),
			 from_kuid(&init_user_ns, cred->euid),
			 from_kuid(&init_user_ns, cred->suid),
			 from_kuid(&init_user_ns, cred->fsuid),
			 from_kgid(&init_user_ns, cred->egid),
			 from_kgid(&init_user_ns, cred->sgid),
			 from_kgid(&init_user_ns, cred->fsgid),
P
Peter Moody 已提交
1167
			 tsk->sessionid, tty);
1168

1169
	get_task_comm(name, tsk);
1170 1171
	audit_log_format(ab, " comm=");
	audit_log_untrustedstring(ab, name);
1172

1173 1174
	if (mm) {
		down_read(&mm->mmap_sem);
1175 1176
		if (mm->exe_file)
			audit_log_d_path(ab, " exe=", &mm->exe_file->f_path);
1177
		up_read(&mm->mmap_sem);
1178
	}
1179
	audit_log_task_context(ab);
1180 1181
}

P
Peter Moody 已提交
1182 1183
EXPORT_SYMBOL(audit_log_task_info);

A
Amy Griffis 已提交
1184
static int audit_log_pid_context(struct audit_context *context, pid_t pid,
1185
				 kuid_t auid, kuid_t uid, unsigned int sessionid,
1186
				 u32 sid, char *comm)
A
Amy Griffis 已提交
1187 1188
{
	struct audit_buffer *ab;
1189
	char *ctx = NULL;
A
Amy Griffis 已提交
1190 1191 1192 1193 1194
	u32 len;
	int rc = 0;

	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
	if (!ab)
1195
		return rc;
A
Amy Griffis 已提交
1196

1197 1198
	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
			 from_kuid(&init_user_ns, auid),
1199
			 from_kuid(&init_user_ns, uid), sessionid);
1200
	if (security_secid_to_secctx(sid, &ctx, &len)) {
1201
		audit_log_format(ab, " obj=(none)");
A
Amy Griffis 已提交
1202
		rc = 1;
1203 1204 1205 1206
	} else {
		audit_log_format(ab, " obj=%s", ctx);
		security_release_secctx(ctx, len);
	}
1207 1208
	audit_log_format(ab, " ocomm=");
	audit_log_untrustedstring(ab, comm);
A
Amy Griffis 已提交
1209 1210 1211 1212 1213
	audit_log_end(ab);

	return rc;
}

1214 1215 1216
/*
 * to_send and len_sent accounting are very loose estimates.  We aren't
 * really worried about a hard cap to MAX_EXECVE_AUDIT_LEN so much as being
L
Lucas De Marchi 已提交
1217
 * within about 500 bytes (next page boundary)
1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230
 *
 * why snprintf?  an int is up to 12 digits long.  if we just assumed when
 * logging that a[%d]= was going to be 16 characters long we would be wasting
 * space in every audit message.  In one 7500 byte message we can log up to
 * about 1000 min size arguments.  That comes down to about 50% waste of space
 * if we didn't do the snprintf to find out how long arg_num_len was.
 */
static int audit_log_single_execve_arg(struct audit_context *context,
					struct audit_buffer **ab,
					int arg_num,
					size_t *len_sent,
					const char __user *p,
					char *buf)
P
Peter Zijlstra 已提交
1231
{
1232 1233
	char arg_num_len_buf[12];
	const char __user *tmp_p = p;
1234 1235
	/* how many digits are in arg_num? 5 is the length of ' a=""' */
	size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 5;
1236 1237 1238 1239 1240 1241 1242
	size_t len, len_left, to_send;
	size_t max_execve_audit_len = MAX_EXECVE_AUDIT_LEN;
	unsigned int i, has_cntl = 0, too_long = 0;
	int ret;

	/* strnlen_user includes the null we don't want to send */
	len_left = len = strnlen_user(p, MAX_ARG_STRLEN) - 1;
P
Peter Zijlstra 已提交
1243

1244 1245 1246 1247 1248 1249
	/*
	 * We just created this mm, if we can't find the strings
	 * we just copied into it something is _very_ wrong. Similar
	 * for strings that are too long, we should not have created
	 * any.
	 */
1250
	if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1251 1252
		WARN_ON(1);
		send_sig(SIGKILL, current, 0);
1253
		return -1;
1254
	}
1255

1256 1257 1258 1259 1260 1261 1262
	/* walk the whole argument looking for non-ascii chars */
	do {
		if (len_left > MAX_EXECVE_AUDIT_LEN)
			to_send = MAX_EXECVE_AUDIT_LEN;
		else
			to_send = len_left;
		ret = copy_from_user(buf, tmp_p, to_send);
P
Peter Zijlstra 已提交
1263
		/*
1264 1265 1266
		 * There is no reason for this copy to be short. We just
		 * copied them here, and the mm hasn't been exposed to user-
		 * space yet.
P
Peter Zijlstra 已提交
1267
		 */
1268
		if (ret) {
P
Peter Zijlstra 已提交
1269 1270
			WARN_ON(1);
			send_sig(SIGKILL, current, 0);
1271
			return -1;
P
Peter Zijlstra 已提交
1272
		}
1273 1274 1275 1276 1277 1278 1279 1280
		buf[to_send] = '\0';
		has_cntl = audit_string_contains_control(buf, to_send);
		if (has_cntl) {
			/*
			 * hex messages get logged as 2 bytes, so we can only
			 * send half as much in each message
			 */
			max_execve_audit_len = MAX_EXECVE_AUDIT_LEN / 2;
P
Peter Zijlstra 已提交
1281 1282
			break;
		}
1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313
		len_left -= to_send;
		tmp_p += to_send;
	} while (len_left > 0);

	len_left = len;

	if (len > max_execve_audit_len)
		too_long = 1;

	/* rewalk the argument actually logging the message */
	for (i = 0; len_left > 0; i++) {
		int room_left;

		if (len_left > max_execve_audit_len)
			to_send = max_execve_audit_len;
		else
			to_send = len_left;

		/* do we have space left to send this argument in this ab? */
		room_left = MAX_EXECVE_AUDIT_LEN - arg_num_len - *len_sent;
		if (has_cntl)
			room_left -= (to_send * 2);
		else
			room_left -= to_send;
		if (room_left < 0) {
			*len_sent = 0;
			audit_log_end(*ab);
			*ab = audit_log_start(context, GFP_KERNEL, AUDIT_EXECVE);
			if (!*ab)
				return 0;
		}
P
Peter Zijlstra 已提交
1314 1315

		/*
1316 1317 1318 1319
		 * first record needs to say how long the original string was
		 * so we can be sure nothing was lost.
		 */
		if ((i == 0) && (too_long))
1320
			audit_log_format(*ab, " a%d_len=%zu", arg_num,
1321 1322 1323 1324 1325 1326
					 has_cntl ? 2*len : len);

		/*
		 * normally arguments are small enough to fit and we already
		 * filled buf above when we checked for control characters
		 * so don't bother with another copy_from_user
P
Peter Zijlstra 已提交
1327
		 */
1328 1329 1330 1331
		if (len >= max_execve_audit_len)
			ret = copy_from_user(buf, p, to_send);
		else
			ret = 0;
1332
		if (ret) {
P
Peter Zijlstra 已提交
1333 1334
			WARN_ON(1);
			send_sig(SIGKILL, current, 0);
1335
			return -1;
P
Peter Zijlstra 已提交
1336
		}
1337 1338 1339
		buf[to_send] = '\0';

		/* actually log it */
1340
		audit_log_format(*ab, " a%d", arg_num);
1341 1342 1343 1344
		if (too_long)
			audit_log_format(*ab, "[%d]", i);
		audit_log_format(*ab, "=");
		if (has_cntl)
1345
			audit_log_n_hex(*ab, buf, to_send);
1346
		else
1347
			audit_log_string(*ab, buf);
1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364

		p += to_send;
		len_left -= to_send;
		*len_sent += arg_num_len;
		if (has_cntl)
			*len_sent += to_send * 2;
		else
			*len_sent += to_send;
	}
	/* include the null we didn't log */
	return len + 1;
}

static void audit_log_execve_info(struct audit_context *context,
				  struct audit_buffer **ab,
				  struct audit_aux_data_execve *axi)
{
1365 1366
	int i, len;
	size_t len_sent = 0;
1367 1368
	const char __user *p;
	char *buf;
P
Peter Zijlstra 已提交
1369

1370 1371 1372 1373
	if (axi->mm != current->mm)
		return; /* execve failed, no additional info */

	p = (const char __user *)axi->mm->arg_start;
P
Peter Zijlstra 已提交
1374

1375
	audit_log_format(*ab, "argc=%d", axi->argc);
1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386

	/*
	 * we need some kernel buffer to hold the userspace args.  Just
	 * allocate one big one rather than allocating one of the right size
	 * for every single argument inside audit_log_single_execve_arg()
	 * should be <8k allocation so should be pretty safe.
	 */
	buf = kmalloc(MAX_EXECVE_AUDIT_LEN + 1, GFP_KERNEL);
	if (!buf) {
		audit_panic("out of memory for argv string\n");
		return;
P
Peter Zijlstra 已提交
1387
	}
1388 1389 1390 1391 1392 1393 1394 1395 1396

	for (i = 0; i < axi->argc; i++) {
		len = audit_log_single_execve_arg(context, ab, i,
						  &len_sent, p, buf);
		if (len <= 0)
			break;
		p += len;
	}
	kfree(buf);
P
Peter Zijlstra 已提交
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
static void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap)
{
	int i;

	audit_log_format(ab, " %s=", prefix);
	CAP_FOR_EACH_U32(i) {
		audit_log_format(ab, "%08x", cap->cap[(_KERNEL_CAPABILITY_U32S-1) - i]);
	}
}

static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name)
{
	kernel_cap_t *perm = &name->fcap.permitted;
	kernel_cap_t *inh = &name->fcap.inheritable;
	int log = 0;

	if (!cap_isclear(*perm)) {
		audit_log_cap(ab, "cap_fp", perm);
		log = 1;
	}
	if (!cap_isclear(*inh)) {
		audit_log_cap(ab, "cap_fi", inh);
		log = 1;
	}

	if (log)
		audit_log_format(ab, " cap_fe=%d cap_fver=%x", name->fcap.fE, name->fcap_ver);
}

A
Al Viro 已提交
1428
static void show_special(struct audit_context *context, int *call_panic)
A
Al Viro 已提交
1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444
{
	struct audit_buffer *ab;
	int i;

	ab = audit_log_start(context, GFP_KERNEL, context->type);
	if (!ab)
		return;

	switch (context->type) {
	case AUDIT_SOCKETCALL: {
		int nargs = context->socketcall.nargs;
		audit_log_format(ab, "nargs=%d", nargs);
		for (i = 0; i < nargs; i++)
			audit_log_format(ab, " a%d=%lx", i,
				context->socketcall.args[i]);
		break; }
A
Al Viro 已提交
1445 1446 1447
	case AUDIT_IPC: {
		u32 osid = context->ipc.osid;

A
Al Viro 已提交
1448
		audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
1449 1450 1451
				 from_kuid(&init_user_ns, context->ipc.uid),
				 from_kgid(&init_user_ns, context->ipc.gid),
				 context->ipc.mode);
A
Al Viro 已提交
1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462
		if (osid) {
			char *ctx = NULL;
			u32 len;
			if (security_secid_to_secctx(osid, &ctx, &len)) {
				audit_log_format(ab, " osid=%u", osid);
				*call_panic = 1;
			} else {
				audit_log_format(ab, " obj=%s", ctx);
				security_release_secctx(ctx, len);
			}
		}
A
Al Viro 已提交
1463 1464 1465 1466 1467
		if (context->ipc.has_perm) {
			audit_log_end(ab);
			ab = audit_log_start(context, GFP_KERNEL,
					     AUDIT_IPC_SET_PERM);
			audit_log_format(ab,
A
Al Viro 已提交
1468
				"qbytes=%lx ouid=%u ogid=%u mode=%#ho",
A
Al Viro 已提交
1469 1470 1471 1472 1473 1474 1475
				context->ipc.qbytes,
				context->ipc.perm_uid,
				context->ipc.perm_gid,
				context->ipc.perm_mode);
			if (!ab)
				return;
		}
A
Al Viro 已提交
1476
		break; }
A
Al Viro 已提交
1477 1478
	case AUDIT_MQ_OPEN: {
		audit_log_format(ab,
A
Al Viro 已提交
1479
			"oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
A
Al Viro 已提交
1480 1481 1482 1483 1484 1485 1486
			"mq_msgsize=%ld mq_curmsgs=%ld",
			context->mq_open.oflag, context->mq_open.mode,
			context->mq_open.attr.mq_flags,
			context->mq_open.attr.mq_maxmsg,
			context->mq_open.attr.mq_msgsize,
			context->mq_open.attr.mq_curmsgs);
		break; }
A
Al Viro 已提交
1487 1488 1489 1490 1491 1492 1493 1494 1495 1496
	case AUDIT_MQ_SENDRECV: {
		audit_log_format(ab,
			"mqdes=%d msg_len=%zd msg_prio=%u "
			"abs_timeout_sec=%ld abs_timeout_nsec=%ld",
			context->mq_sendrecv.mqdes,
			context->mq_sendrecv.msg_len,
			context->mq_sendrecv.msg_prio,
			context->mq_sendrecv.abs_timeout.tv_sec,
			context->mq_sendrecv.abs_timeout.tv_nsec);
		break; }
A
Al Viro 已提交
1497 1498 1499 1500 1501
	case AUDIT_MQ_NOTIFY: {
		audit_log_format(ab, "mqdes=%d sigev_signo=%d",
				context->mq_notify.mqdes,
				context->mq_notify.sigev_signo);
		break; }
A
Al Viro 已提交
1502 1503 1504 1505 1506 1507 1508 1509 1510
	case AUDIT_MQ_GETSETATTR: {
		struct mq_attr *attr = &context->mq_getsetattr.mqstat;
		audit_log_format(ab,
			"mqdes=%d mq_flags=0x%lx mq_maxmsg=%ld mq_msgsize=%ld "
			"mq_curmsgs=%ld ",
			context->mq_getsetattr.mqdes,
			attr->mq_flags, attr->mq_maxmsg,
			attr->mq_msgsize, attr->mq_curmsgs);
		break; }
A
Al Viro 已提交
1511 1512 1513 1514 1515 1516
	case AUDIT_CAPSET: {
		audit_log_format(ab, "pid=%d", context->capset.pid);
		audit_log_cap(ab, "cap_pi", &context->capset.cap.inheritable);
		audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
		audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
		break; }
A
Al Viro 已提交
1517 1518 1519 1520
	case AUDIT_MMAP: {
		audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
				 context->mmap.flags);
		break; }
A
Al Viro 已提交
1521 1522 1523 1524
	}
	audit_log_end(ab);
}

1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539
static void audit_log_name(struct audit_context *context, struct audit_names *n,
			   int record_num, int *call_panic)
{
	struct audit_buffer *ab;
	ab = audit_log_start(context, GFP_KERNEL, AUDIT_PATH);
	if (!ab)
		return; /* audit_panic has been called */

	audit_log_format(ab, "item=%d", record_num);

	if (n->name) {
		switch (n->name_len) {
		case AUDIT_NAME_FULL:
			/* log the full path */
			audit_log_format(ab, " name=");
1540
			audit_log_untrustedstring(ab, n->name->name);
1541 1542 1543 1544
			break;
		case 0:
			/* name was specified as a relative path and the
			 * directory component is the cwd */
1545
			audit_log_d_path(ab, " name=", &context->pwd);
1546 1547 1548 1549
			break;
		default:
			/* log the name's directory component */
			audit_log_format(ab, " name=");
1550
			audit_log_n_untrustedstring(ab, n->name->name,
1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563
						    n->name_len);
		}
	} else
		audit_log_format(ab, " name=(null)");

	if (n->ino != (unsigned long)-1) {
		audit_log_format(ab, " inode=%lu"
				 " dev=%02x:%02x mode=%#ho"
				 " ouid=%u ogid=%u rdev=%02x:%02x",
				 n->ino,
				 MAJOR(n->dev),
				 MINOR(n->dev),
				 n->mode,
1564 1565
				 from_kuid(&init_user_ns, n->uid),
				 from_kgid(&init_user_ns, n->gid),
1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586
				 MAJOR(n->rdev),
				 MINOR(n->rdev));
	}
	if (n->osid != 0) {
		char *ctx = NULL;
		u32 len;
		if (security_secid_to_secctx(
			n->osid, &ctx, &len)) {
			audit_log_format(ab, " osid=%u", n->osid);
			*call_panic = 2;
		} else {
			audit_log_format(ab, " obj=%s", ctx);
			security_release_secctx(ctx, len);
		}
	}

	audit_log_fcaps(ab, n);

	audit_log_end(ab);
}

1587
static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
L
Linus Torvalds 已提交
1588
{
S
Steve Grubb 已提交
1589
	int i, call_panic = 0;
L
Linus Torvalds 已提交
1590
	struct audit_buffer *ab;
1591
	struct audit_aux_data *aux;
1592
	struct audit_names *n;
L
Linus Torvalds 已提交
1593

1594
	/* tsk == current */
1595
	context->personality = tsk->personality;
1596 1597

	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
L
Linus Torvalds 已提交
1598 1599
	if (!ab)
		return;		/* audit_panic has been called */
1600 1601
	audit_log_format(ab, "arch=%x syscall=%d",
			 context->arch, context->major);
L
Linus Torvalds 已提交
1602 1603 1604
	if (context->personality != PER_LINUX)
		audit_log_format(ab, " per=%lx", context->personality);
	if (context->return_valid)
D
Daniel Walker 已提交
1605
		audit_log_format(ab, " success=%s exit=%ld",
1606 1607
				 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
				 context->return_code);
A
Alan Cox 已提交
1608

L
Linus Torvalds 已提交
1609
	audit_log_format(ab,
P
Peter Moody 已提交
1610 1611 1612 1613 1614 1615
			 " a0=%lx a1=%lx a2=%lx a3=%lx items=%d",
			 context->argv[0],
			 context->argv[1],
			 context->argv[2],
			 context->argv[3],
			 context->name_count);
A
Alan Cox 已提交
1616

1617
	audit_log_task_info(ab, tsk);
1618
	audit_log_key(ab, context->filterkey);
L
Linus Torvalds 已提交
1619 1620
	audit_log_end(ab);

1621
	for (aux = context->aux; aux; aux = aux->next) {
1622

1623
		ab = audit_log_start(context, GFP_KERNEL, aux->type);
L
Linus Torvalds 已提交
1624 1625 1626 1627
		if (!ab)
			continue; /* audit_panic has been called */

		switch (aux->type) {
1628

A
Al Viro 已提交
1629 1630
		case AUDIT_EXECVE: {
			struct audit_aux_data_execve *axi = (void *)aux;
1631
			audit_log_execve_info(context, &ab, axi);
A
Al Viro 已提交
1632
			break; }
S
Steve Grubb 已提交
1633

1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647
		case AUDIT_BPRM_FCAPS: {
			struct audit_aux_data_bprm_fcaps *axs = (void *)aux;
			audit_log_format(ab, "fver=%x", axs->fcap_ver);
			audit_log_cap(ab, "fp", &axs->fcap.permitted);
			audit_log_cap(ab, "fi", &axs->fcap.inheritable);
			audit_log_format(ab, " fe=%d", axs->fcap.fE);
			audit_log_cap(ab, "old_pp", &axs->old_pcap.permitted);
			audit_log_cap(ab, "old_pi", &axs->old_pcap.inheritable);
			audit_log_cap(ab, "old_pe", &axs->old_pcap.effective);
			audit_log_cap(ab, "new_pp", &axs->new_pcap.permitted);
			audit_log_cap(ab, "new_pi", &axs->new_pcap.inheritable);
			audit_log_cap(ab, "new_pe", &axs->new_pcap.effective);
			break; }

L
Linus Torvalds 已提交
1648 1649 1650 1651
		}
		audit_log_end(ab);
	}

A
Al Viro 已提交
1652
	if (context->type)
A
Al Viro 已提交
1653
		show_special(context, &call_panic);
A
Al Viro 已提交
1654

A
Al Viro 已提交
1655 1656 1657 1658 1659 1660 1661 1662 1663
	if (context->fds[0] >= 0) {
		ab = audit_log_start(context, GFP_KERNEL, AUDIT_FD_PAIR);
		if (ab) {
			audit_log_format(ab, "fd0=%d fd1=%d",
					context->fds[0], context->fds[1]);
			audit_log_end(ab);
		}
	}

1664 1665 1666 1667 1668 1669 1670 1671 1672 1673
	if (context->sockaddr_len) {
		ab = audit_log_start(context, GFP_KERNEL, AUDIT_SOCKADDR);
		if (ab) {
			audit_log_format(ab, "saddr=");
			audit_log_n_hex(ab, (void *)context->sockaddr,
					context->sockaddr_len);
			audit_log_end(ab);
		}
	}

A
Amy Griffis 已提交
1674 1675 1676 1677 1678
	for (aux = context->aux_pids; aux; aux = aux->next) {
		struct audit_aux_data_pids *axs = (void *)aux;

		for (i = 0; i < axs->pid_count; i++)
			if (audit_log_pid_context(context, axs->target_pid[i],
1679 1680
						  axs->target_auid[i],
						  axs->target_uid[i],
1681
						  axs->target_sessionid[i],
1682 1683
						  axs->target_sid[i],
						  axs->target_comm[i]))
A
Amy Griffis 已提交
1684
				call_panic = 1;
A
Al Viro 已提交
1685 1686
	}

A
Amy Griffis 已提交
1687 1688
	if (context->target_pid &&
	    audit_log_pid_context(context, context->target_pid,
1689
				  context->target_auid, context->target_uid,
1690
				  context->target_sessionid,
1691
				  context->target_sid, context->target_comm))
A
Amy Griffis 已提交
1692 1693
			call_panic = 1;

1694
	if (context->pwd.dentry && context->pwd.mnt) {
1695
		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1696
		if (ab) {
1697
			audit_log_d_path(ab, " cwd=", &context->pwd);
1698 1699 1700
			audit_log_end(ab);
		}
	}
1701

1702 1703 1704
	i = 0;
	list_for_each_entry(n, &context->names_list, list)
		audit_log_name(context, n, i++, &call_panic);
E
Eric Paris 已提交
1705 1706 1707 1708 1709

	/* Send end of event record to help user space know we are finished */
	ab = audit_log_start(context, GFP_KERNEL, AUDIT_EOE);
	if (ab)
		audit_log_end(ab);
S
Steve Grubb 已提交
1710 1711
	if (call_panic)
		audit_panic("error converting sid to string");
L
Linus Torvalds 已提交
1712 1713
}

1714 1715 1716 1717
/**
 * audit_free - free a per-task audit context
 * @tsk: task whose audit context block to free
 *
1718
 * Called from copy_process and do_exit
1719
 */
1720
void __audit_free(struct task_struct *tsk)
L
Linus Torvalds 已提交
1721 1722 1723 1724
{
	struct audit_context *context;

	context = audit_get_context(tsk, 0, 0);
1725
	if (!context)
L
Linus Torvalds 已提交
1726 1727 1728
		return;

	/* Check for system calls that do not go through the exit
D
Daniel Walker 已提交
1729 1730
	 * function (e.g., exit_group), then free context block.
	 * We use GFP_ATOMIC here because we might be doing this
1731
	 * in the context of the idle thread */
1732
	/* that can happen only if we are called from do_exit() */
1733
	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1734
		audit_log_exit(context, tsk);
A
Al Viro 已提交
1735 1736
	if (!list_empty(&context->killed_trees))
		audit_kill_trees(&context->killed_trees);
L
Linus Torvalds 已提交
1737 1738 1739 1740

	audit_free_context(context);
}

1741 1742 1743 1744 1745 1746 1747 1748 1749 1750
/**
 * audit_syscall_entry - fill in an audit record at syscall entry
 * @arch: architecture type
 * @major: major syscall type (function)
 * @a1: additional syscall register 1
 * @a2: additional syscall register 2
 * @a3: additional syscall register 3
 * @a4: additional syscall register 4
 *
 * Fill in audit context at syscall entry.  This only happens if the
L
Linus Torvalds 已提交
1751 1752 1753 1754 1755
 * audit context was created when the task was created and the state or
 * filters demand the audit context be built.  If the state from the
 * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT,
 * then the record will be written at syscall exit time (otherwise, it
 * will only be written if another part of the kernel requests that it
1756 1757
 * be written).
 */
1758
void __audit_syscall_entry(int arch, int major,
L
Linus Torvalds 已提交
1759 1760 1761
			 unsigned long a1, unsigned long a2,
			 unsigned long a3, unsigned long a4)
{
1762
	struct task_struct *tsk = current;
L
Linus Torvalds 已提交
1763 1764 1765
	struct audit_context *context = tsk->audit_context;
	enum audit_state     state;

1766
	if (!context)
R
Roland McGrath 已提交
1767
		return;
L
Linus Torvalds 已提交
1768 1769 1770 1771 1772 1773

	BUG_ON(context->in_syscall || context->name_count);

	if (!audit_enabled)
		return;

1774
	context->arch	    = arch;
L
Linus Torvalds 已提交
1775 1776 1777 1778 1779 1780 1781
	context->major      = major;
	context->argv[0]    = a1;
	context->argv[1]    = a2;
	context->argv[2]    = a3;
	context->argv[3]    = a4;

	state = context->state;
1782
	context->dummy = !audit_n_rules;
1783 1784
	if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
		context->prio = 0;
1785
		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1786
	}
1787
	if (state == AUDIT_DISABLED)
L
Linus Torvalds 已提交
1788 1789
		return;

1790
	context->serial     = 0;
L
Linus Torvalds 已提交
1791 1792
	context->ctime      = CURRENT_TIME;
	context->in_syscall = 1;
1793
	context->current_state  = state;
A
Alexander Viro 已提交
1794
	context->ppid       = 0;
L
Linus Torvalds 已提交
1795 1796
}

1797 1798
/**
 * audit_syscall_exit - deallocate audit context after a system call
1799 1800
 * @success: success value of the syscall
 * @return_code: return value of the syscall
1801 1802
 *
 * Tear down after system call.  If the audit context has been marked as
L
Linus Torvalds 已提交
1803
 * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1804
 * filtering, or because some other part of the kernel wrote an audit
L
Linus Torvalds 已提交
1805
 * message), then write out the syscall information.  In call cases,
1806 1807
 * free the names stored from getname().
 */
1808
void __audit_syscall_exit(int success, long return_code)
L
Linus Torvalds 已提交
1809
{
1810
	struct task_struct *tsk = current;
L
Linus Torvalds 已提交
1811 1812
	struct audit_context *context;

1813 1814 1815 1816
	if (success)
		success = AUDITSC_SUCCESS;
	else
		success = AUDITSC_FAILURE;
L
Linus Torvalds 已提交
1817

1818
	context = audit_get_context(tsk, success, return_code);
1819
	if (!context)
1820
		return;
L
Linus Torvalds 已提交
1821

1822
	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1823
		audit_log_exit(context, tsk);
L
Linus Torvalds 已提交
1824 1825

	context->in_syscall = 0;
1826
	context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1827

A
Al Viro 已提交
1828 1829 1830
	if (!list_empty(&context->killed_trees))
		audit_kill_trees(&context->killed_trees);

A
Al Viro 已提交
1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843
	audit_free_names(context);
	unroll_tree_refs(context, NULL, 0);
	audit_free_aux(context);
	context->aux = NULL;
	context->aux_pids = NULL;
	context->target_pid = 0;
	context->target_sid = 0;
	context->sockaddr_len = 0;
	context->type = 0;
	context->fds[0] = -1;
	if (context->state != AUDIT_RECORD_CONTEXT) {
		kfree(context->filterkey);
		context->filterkey = NULL;
L
Linus Torvalds 已提交
1844
	}
A
Al Viro 已提交
1845
	tsk->audit_context = context;
L
Linus Torvalds 已提交
1846 1847
}

A
Al Viro 已提交
1848 1849 1850 1851 1852 1853 1854
static inline void handle_one(const struct inode *inode)
{
#ifdef CONFIG_AUDIT_TREE
	struct audit_context *context;
	struct audit_tree_refs *p;
	struct audit_chunk *chunk;
	int count;
1855
	if (likely(hlist_empty(&inode->i_fsnotify_marks)))
A
Al Viro 已提交
1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867
		return;
	context = current->audit_context;
	p = context->trees;
	count = context->tree_count;
	rcu_read_lock();
	chunk = audit_tree_lookup(inode);
	rcu_read_unlock();
	if (!chunk)
		return;
	if (likely(put_tree_ref(context, chunk)))
		return;
	if (unlikely(!grow_tree_refs(context))) {
E
Eric Paris 已提交
1868
		printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
A
Al Viro 已提交
1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897
		audit_set_auditable(context);
		audit_put_chunk(chunk);
		unroll_tree_refs(context, p, count);
		return;
	}
	put_tree_ref(context, chunk);
#endif
}

static void handle_path(const struct dentry *dentry)
{
#ifdef CONFIG_AUDIT_TREE
	struct audit_context *context;
	struct audit_tree_refs *p;
	const struct dentry *d, *parent;
	struct audit_chunk *drop;
	unsigned long seq;
	int count;

	context = current->audit_context;
	p = context->trees;
	count = context->tree_count;
retry:
	drop = NULL;
	d = dentry;
	rcu_read_lock();
	seq = read_seqbegin(&rename_lock);
	for(;;) {
		struct inode *inode = d->d_inode;
1898
		if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) {
A
Al Viro 已提交
1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927
			struct audit_chunk *chunk;
			chunk = audit_tree_lookup(inode);
			if (chunk) {
				if (unlikely(!put_tree_ref(context, chunk))) {
					drop = chunk;
					break;
				}
			}
		}
		parent = d->d_parent;
		if (parent == d)
			break;
		d = parent;
	}
	if (unlikely(read_seqretry(&rename_lock, seq) || drop)) {  /* in this order */
		rcu_read_unlock();
		if (!drop) {
			/* just a race with rename */
			unroll_tree_refs(context, p, count);
			goto retry;
		}
		audit_put_chunk(drop);
		if (grow_tree_refs(context)) {
			/* OK, got more space */
			unroll_tree_refs(context, p, count);
			goto retry;
		}
		/* too bad */
		printk(KERN_WARNING
E
Eric Paris 已提交
1928
			"out of memory, audit has lost a tree reference\n");
A
Al Viro 已提交
1929 1930 1931 1932 1933 1934 1935 1936
		unroll_tree_refs(context, p, count);
		audit_set_auditable(context);
		return;
	}
	rcu_read_unlock();
#endif
}

1937 1938
static struct audit_names *audit_alloc_name(struct audit_context *context,
						unsigned char type)
1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952
{
	struct audit_names *aname;

	if (context->name_count < AUDIT_NAMES) {
		aname = &context->preallocated_names[context->name_count];
		memset(aname, 0, sizeof(*aname));
	} else {
		aname = kzalloc(sizeof(*aname), GFP_NOFS);
		if (!aname)
			return NULL;
		aname->should_free = true;
	}

	aname->ino = (unsigned long)-1;
1953
	aname->type = type;
1954 1955 1956 1957 1958 1959 1960 1961 1962
	list_add_tail(&aname->list, &context->names_list);

	context->name_count++;
#if AUDIT_DEBUG
	context->ino_count++;
#endif
	return aname;
}

1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985
/**
 * audit_reusename - fill out filename with info from existing entry
 * @uptr: userland ptr to pathname
 *
 * Search the audit_names list for the current audit context. If there is an
 * existing entry with a matching "uptr" then return the filename
 * associated with that audit_name. If not, return NULL.
 */
struct filename *
__audit_reusename(const __user char *uptr)
{
	struct audit_context *context = current->audit_context;
	struct audit_names *n;

	list_for_each_entry(n, &context->names_list, list) {
		if (!n->name)
			continue;
		if (n->name->uptr == uptr)
			return n->name;
	}
	return NULL;
}

1986 1987 1988 1989 1990 1991 1992
/**
 * audit_getname - add a name to the list
 * @name: name to add
 *
 * Add a name to the list of audit names for this context.
 * Called from fs/namei.c:getname().
 */
1993
void __audit_getname(struct filename *name)
L
Linus Torvalds 已提交
1994 1995
{
	struct audit_context *context = current->audit_context;
1996
	struct audit_names *n;
L
Linus Torvalds 已提交
1997 1998 1999 2000 2001 2002 2003 2004 2005

	if (!context->in_syscall) {
#if AUDIT_DEBUG == 2
		printk(KERN_ERR "%s:%d(:%d): ignoring getname(%p)\n",
		       __FILE__, __LINE__, context->serial, name);
		dump_stack();
#endif
		return;
	}
2006

2007 2008 2009 2010 2011
#if AUDIT_DEBUG
	/* The filename _must_ have a populated ->name */
	BUG_ON(!name->name);
#endif

2012
	n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
2013 2014 2015 2016 2017 2018
	if (!n)
		return;

	n->name = name;
	n->name_len = AUDIT_NAME_FULL;
	n->name_put = true;
2019
	name->aname = n;
2020

2021 2022
	if (!context->pwd.dentry)
		get_fs_pwd(current->fs, &context->pwd);
L
Linus Torvalds 已提交
2023 2024
}

2025 2026 2027 2028 2029 2030 2031
/* audit_putname - intercept a putname request
 * @name: name to intercept and delay for putname
 *
 * If we have stored the name from getname in the audit context,
 * then we delay the putname until syscall exit.
 * Called from include/linux/fs.h:putname().
 */
2032
void audit_putname(struct filename *name)
L
Linus Torvalds 已提交
2033 2034 2035 2036 2037 2038 2039 2040 2041
{
	struct audit_context *context = current->audit_context;

	BUG_ON(!context);
	if (!context->in_syscall) {
#if AUDIT_DEBUG == 2
		printk(KERN_ERR "%s:%d(:%d): __putname(%p)\n",
		       __FILE__, __LINE__, context->serial, name);
		if (context->name_count) {
2042
			struct audit_names *n;
L
Linus Torvalds 已提交
2043
			int i;
2044 2045

			list_for_each_entry(n, &context->names_list, list)
L
Linus Torvalds 已提交
2046
				printk(KERN_ERR "name[%d] = %p = %s\n", i,
2047
				       n->name, n->name->name ?: "(null)");
2048
			}
L
Linus Torvalds 已提交
2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060
#endif
		__putname(name);
	}
#if AUDIT_DEBUG
	else {
		++context->put_count;
		if (context->put_count > context->name_count) {
			printk(KERN_ERR "%s:%d(:%d): major=%d"
			       " in_syscall=%d putname(%p) name_count=%d"
			       " put_count=%d\n",
			       __FILE__, __LINE__,
			       context->serial, context->major,
2061 2062
			       context->in_syscall, name->name,
			       context->name_count, context->put_count);
L
Linus Torvalds 已提交
2063 2064 2065 2066 2067 2068
			dump_stack();
		}
	}
#endif
}

2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089
static inline int audit_copy_fcaps(struct audit_names *name, const struct dentry *dentry)
{
	struct cpu_vfs_cap_data caps;
	int rc;

	if (!dentry)
		return 0;

	rc = get_vfs_caps_from_disk(dentry, &caps);
	if (rc)
		return rc;

	name->fcap.permitted = caps.permitted;
	name->fcap.inheritable = caps.inheritable;
	name->fcap.fE = !!(caps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
	name->fcap_ver = (caps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;

	return 0;
}


2090
/* Copy inode data into an audit_names. */
2091 2092
static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
			     const struct inode *inode)
2093
{
2094 2095 2096 2097 2098 2099
	name->ino   = inode->i_ino;
	name->dev   = inode->i_sb->s_dev;
	name->mode  = inode->i_mode;
	name->uid   = inode->i_uid;
	name->gid   = inode->i_gid;
	name->rdev  = inode->i_rdev;
2100
	security_inode_getsecid(inode, &name->osid);
2101
	audit_copy_fcaps(name, dentry);
2102 2103
}

2104
/**
2105
 * __audit_inode - store the inode and device from a lookup
2106
 * @name: name being audited
2107
 * @dentry: dentry being audited
2108
 * @parent: does this dentry represent the parent?
2109
 */
2110
void __audit_inode(struct filename *name, const struct dentry *dentry,
2111
		   unsigned int parent)
L
Linus Torvalds 已提交
2112 2113
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2114
	const struct inode *inode = dentry->d_inode;
2115
	struct audit_names *n;
L
Linus Torvalds 已提交
2116 2117 2118

	if (!context->in_syscall)
		return;
2119

2120 2121 2122
	if (!name)
		goto out_alloc;

2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142
#if AUDIT_DEBUG
	/* The struct filename _must_ have a populated ->name */
	BUG_ON(!name->name);
#endif
	/*
	 * If we have a pointer to an audit_names entry already, then we can
	 * just use it directly if the type is correct.
	 */
	n = name->aname;
	if (n) {
		if (parent) {
			if (n->type == AUDIT_TYPE_PARENT ||
			    n->type == AUDIT_TYPE_UNKNOWN)
				goto out;
		} else {
			if (n->type != AUDIT_TYPE_PARENT)
				goto out;
		}
	}

2143
	list_for_each_entry_reverse(n, &context->names_list, list) {
2144
		/* does the name pointer match? */
2145
		if (!n->name || n->name->name != name->name)
2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156
			continue;

		/* match the correct record type */
		if (parent) {
			if (n->type == AUDIT_TYPE_PARENT ||
			    n->type == AUDIT_TYPE_UNKNOWN)
				goto out;
		} else {
			if (n->type != AUDIT_TYPE_PARENT)
				goto out;
		}
L
Linus Torvalds 已提交
2157
	}
2158

2159
out_alloc:
2160 2161 2162
	/* unable to find the name from a previous getname(). Allocate a new
	 * anonymous entry.
	 */
2163
	n = audit_alloc_name(context, AUDIT_TYPE_NORMAL);
2164 2165 2166
	if (!n)
		return;
out:
2167
	if (parent) {
2168
		n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL;
2169 2170 2171 2172 2173
		n->type = AUDIT_TYPE_PARENT;
	} else {
		n->name_len = AUDIT_NAME_FULL;
		n->type = AUDIT_TYPE_NORMAL;
	}
A
Al Viro 已提交
2174
	handle_path(dentry);
2175
	audit_copy_inode(n, dentry, inode);
2176 2177 2178
}

/**
2179
 * __audit_inode_child - collect inode info for created/removed objects
2180
 * @parent: inode of dentry parent
2181
 * @dentry: dentry being audited
2182
 * @type:   AUDIT_TYPE_* value that we're looking for
2183 2184 2185 2186 2187 2188 2189 2190 2191
 *
 * For syscalls that create or remove filesystem objects, audit_inode
 * can only collect information for the filesystem object's parent.
 * This call updates the audit context with the child's information.
 * Syscalls that create a new filesystem object must be hooked after
 * the object is created.  Syscalls that remove a filesystem object
 * must be hooked prior, in order to capture the target inode during
 * unsuccessful attempts.
 */
2192
void __audit_inode_child(const struct inode *parent,
2193 2194
			 const struct dentry *dentry,
			 const unsigned char type)
2195 2196
{
	struct audit_context *context = current->audit_context;
2197
	const struct inode *inode = dentry->d_inode;
2198
	const char *dname = dentry->d_name.name;
2199
	struct audit_names *n, *found_parent = NULL, *found_child = NULL;
2200 2201 2202 2203

	if (!context->in_syscall)
		return;

A
Al Viro 已提交
2204 2205
	if (inode)
		handle_one(inode);
2206

2207
	/* look for a parent entry first */
2208
	list_for_each_entry(n, &context->names_list, list) {
2209
		if (!n->name || n->type != AUDIT_TYPE_PARENT)
A
Amy Griffis 已提交
2210 2211 2212
			continue;

		if (n->ino == parent->i_ino &&
2213
		    !audit_compare_dname_path(dname, n->name->name, n->name_len)) {
2214 2215
			found_parent = n;
			break;
A
Amy Griffis 已提交
2216
		}
A
Amy Griffis 已提交
2217
	}
2218

2219
	/* is there a matching child entry? */
2220
	list_for_each_entry(n, &context->names_list, list) {
2221 2222 2223 2224 2225 2226
		/* can only match entries that have a name */
		if (!n->name || n->type != type)
			continue;

		/* if we found a parent, make sure this one is a child of it */
		if (found_parent && (n->name != found_parent->name))
A
Amy Griffis 已提交
2227 2228
			continue;

2229 2230
		if (!strcmp(dname, n->name->name) ||
		    !audit_compare_dname_path(dname, n->name->name,
2231 2232
						found_parent ?
						found_parent->name_len :
2233
						AUDIT_NAME_FULL)) {
2234 2235
			found_child = n;
			break;
A
Amy Griffis 已提交
2236
		}
S
Steve Grubb 已提交
2237
	}
A
Amy Griffis 已提交
2238 2239

	if (!found_parent) {
2240 2241
		/* create a new, "anonymous" parent record */
		n = audit_alloc_name(context, AUDIT_TYPE_PARENT);
2242
		if (!n)
S
Steve Grubb 已提交
2243
			return;
2244
		audit_copy_inode(n, NULL, parent);
2245
	}
A
Amy Griffis 已提交
2246 2247

	if (!found_child) {
2248 2249
		found_child = audit_alloc_name(context, type);
		if (!found_child)
A
Amy Griffis 已提交
2250 2251 2252 2253 2254 2255
			return;

		/* Re-use the name belonging to the slot for a matching parent
		 * directory. All names for this context are relinquished in
		 * audit_free_names() */
		if (found_parent) {
2256 2257
			found_child->name = found_parent->name;
			found_child->name_len = AUDIT_NAME_FULL;
A
Amy Griffis 已提交
2258
			/* don't call __putname() */
2259
			found_child->name_put = false;
A
Amy Griffis 已提交
2260 2261
		}
	}
2262 2263 2264 2265
	if (inode)
		audit_copy_inode(found_child, dentry, inode);
	else
		found_child->ino = (unsigned long)-1;
2266
}
2267
EXPORT_SYMBOL_GPL(__audit_inode_child);
2268

2269 2270 2271 2272 2273 2274 2275 2276
/**
 * auditsc_get_stamp - get local copies of audit_context values
 * @ctx: audit_context for the task
 * @t: timespec to store time recorded in the audit_context
 * @serial: serial value that is recorded in the audit_context
 *
 * Also sets the context as auditable.
 */
2277
int auditsc_get_stamp(struct audit_context *ctx,
2278
		       struct timespec *t, unsigned int *serial)
L
Linus Torvalds 已提交
2279
{
2280 2281
	if (!ctx->in_syscall)
		return 0;
2282 2283
	if (!ctx->serial)
		ctx->serial = audit_serial();
2284 2285 2286
	t->tv_sec  = ctx->ctime.tv_sec;
	t->tv_nsec = ctx->ctime.tv_nsec;
	*serial    = ctx->serial;
2287 2288 2289 2290
	if (!ctx->prio) {
		ctx->prio = 1;
		ctx->current_state = AUDIT_RECORD_CONTEXT;
	}
2291
	return 1;
L
Linus Torvalds 已提交
2292 2293
}

2294 2295 2296
/* global counter which is incremented every time something logs in */
static atomic_t session_id = ATOMIC_INIT(0);

2297
/**
2298
 * audit_set_loginuid - set current task's audit_context loginuid
2299 2300 2301 2302 2303 2304
 * @loginuid: loginuid value
 *
 * Returns 0.
 *
 * Called (set) from fs/proc/base.c::proc_loginuid_write().
 */
2305
int audit_set_loginuid(kuid_t loginuid)
L
Linus Torvalds 已提交
2306
{
2307
	struct task_struct *task = current;
2308
	struct audit_context *context = task->audit_context;
2309
	unsigned int sessionid;
2310

2311
#ifdef CONFIG_AUDIT_LOGINUID_IMMUTABLE
2312
	if (uid_valid(task->loginuid))
2313 2314 2315 2316 2317 2318 2319
		return -EPERM;
#else /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */
	if (!capable(CAP_AUDIT_CONTROL))
		return -EPERM;
#endif  /* CONFIG_AUDIT_LOGINUID_IMMUTABLE */

	sessionid = atomic_inc_return(&session_id);
A
Al Viro 已提交
2320 2321 2322 2323 2324 2325
	if (context && context->in_syscall) {
		struct audit_buffer *ab;

		ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_LOGIN);
		if (ab) {
			audit_log_format(ab, "login pid=%d uid=%u "
2326 2327
				"old auid=%u new auid=%u"
				" old ses=%u new ses=%u",
2328 2329
				task->pid,
				from_kuid(&init_user_ns, task_uid(task)),
2330 2331
				from_kuid(&init_user_ns, task->loginuid),
				from_kuid(&init_user_ns, loginuid),
2332
				task->sessionid, sessionid);
A
Al Viro 已提交
2333
			audit_log_end(ab);
2334
		}
L
Linus Torvalds 已提交
2335
	}
2336
	task->sessionid = sessionid;
A
Al Viro 已提交
2337
	task->loginuid = loginuid;
L
Linus Torvalds 已提交
2338 2339 2340
	return 0;
}

2341 2342 2343 2344
/**
 * __audit_mq_open - record audit data for a POSIX MQ open
 * @oflag: open flag
 * @mode: mode bits
R
Randy Dunlap 已提交
2345
 * @attr: queue attributes
2346 2347
 *
 */
A
Al Viro 已提交
2348
void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
2349 2350 2351
{
	struct audit_context *context = current->audit_context;

A
Al Viro 已提交
2352 2353 2354 2355
	if (attr)
		memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
	else
		memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2356

A
Al Viro 已提交
2357 2358
	context->mq_open.oflag = oflag;
	context->mq_open.mode = mode;
2359

A
Al Viro 已提交
2360
	context->type = AUDIT_MQ_OPEN;
2361 2362 2363
}

/**
A
Al Viro 已提交
2364
 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2365 2366 2367
 * @mqdes: MQ descriptor
 * @msg_len: Message length
 * @msg_prio: Message priority
A
Al Viro 已提交
2368
 * @abs_timeout: Message timeout in absolute time
2369 2370
 *
 */
A
Al Viro 已提交
2371 2372
void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
			const struct timespec *abs_timeout)
2373 2374
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2375
	struct timespec *p = &context->mq_sendrecv.abs_timeout;
2376

A
Al Viro 已提交
2377 2378 2379 2380
	if (abs_timeout)
		memcpy(p, abs_timeout, sizeof(struct timespec));
	else
		memset(p, 0, sizeof(struct timespec));
2381

A
Al Viro 已提交
2382 2383 2384
	context->mq_sendrecv.mqdes = mqdes;
	context->mq_sendrecv.msg_len = msg_len;
	context->mq_sendrecv.msg_prio = msg_prio;
2385

A
Al Viro 已提交
2386
	context->type = AUDIT_MQ_SENDRECV;
2387 2388 2389 2390 2391
}

/**
 * __audit_mq_notify - record audit data for a POSIX MQ notify
 * @mqdes: MQ descriptor
R
Randy Dunlap 已提交
2392
 * @notification: Notification event
2393 2394 2395
 *
 */

A
Al Viro 已提交
2396
void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2397 2398 2399
{
	struct audit_context *context = current->audit_context;

A
Al Viro 已提交
2400 2401 2402 2403
	if (notification)
		context->mq_notify.sigev_signo = notification->sigev_signo;
	else
		context->mq_notify.sigev_signo = 0;
2404

A
Al Viro 已提交
2405 2406
	context->mq_notify.mqdes = mqdes;
	context->type = AUDIT_MQ_NOTIFY;
2407 2408 2409 2410 2411 2412 2413 2414
}

/**
 * __audit_mq_getsetattr - record audit data for a POSIX MQ get/set attribute
 * @mqdes: MQ descriptor
 * @mqstat: MQ flags
 *
 */
A
Al Viro 已提交
2415
void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2416 2417
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2418 2419 2420
	context->mq_getsetattr.mqdes = mqdes;
	context->mq_getsetattr.mqstat = *mqstat;
	context->type = AUDIT_MQ_GETSETATTR;
2421 2422
}

2423
/**
S
Steve Grubb 已提交
2424 2425 2426 2427
 * audit_ipc_obj - record audit data for ipc object
 * @ipcp: ipc permissions
 *
 */
A
Al Viro 已提交
2428
void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
S
Steve Grubb 已提交
2429 2430
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2431 2432 2433
	context->ipc.uid = ipcp->uid;
	context->ipc.gid = ipcp->gid;
	context->ipc.mode = ipcp->mode;
A
Al Viro 已提交
2434
	context->ipc.has_perm = 0;
A
Al Viro 已提交
2435 2436
	security_ipc_getsecid(ipcp, &context->ipc.osid);
	context->type = AUDIT_IPC;
S
Steve Grubb 已提交
2437 2438 2439 2440
}

/**
 * audit_ipc_set_perm - record audit data for new ipc permissions
2441 2442 2443 2444 2445
 * @qbytes: msgq bytes
 * @uid: msgq user id
 * @gid: msgq group id
 * @mode: msgq mode (permissions)
 *
A
Al Viro 已提交
2446
 * Called only after audit_ipc_obj().
2447
 */
A
Al Viro 已提交
2448
void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
L
Linus Torvalds 已提交
2449 2450 2451
{
	struct audit_context *context = current->audit_context;

A
Al Viro 已提交
2452 2453 2454 2455 2456
	context->ipc.qbytes = qbytes;
	context->ipc.perm_uid = uid;
	context->ipc.perm_gid = gid;
	context->ipc.perm_mode = mode;
	context->ipc.has_perm = 1;
L
Linus Torvalds 已提交
2457
}
2458

2459
int __audit_bprm(struct linux_binprm *bprm)
A
Al Viro 已提交
2460 2461 2462 2463
{
	struct audit_aux_data_execve *ax;
	struct audit_context *context = current->audit_context;

P
Peter Zijlstra 已提交
2464
	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
A
Al Viro 已提交
2465 2466 2467 2468 2469
	if (!ax)
		return -ENOMEM;

	ax->argc = bprm->argc;
	ax->envc = bprm->envc;
P
Peter Zijlstra 已提交
2470
	ax->mm = bprm->mm;
A
Al Viro 已提交
2471 2472 2473 2474 2475 2476 2477
	ax->d.type = AUDIT_EXECVE;
	ax->d.next = context->aux;
	context->aux = (void *)ax;
	return 0;
}


2478 2479 2480 2481 2482 2483
/**
 * audit_socketcall - record audit data for sys_socketcall
 * @nargs: number of args
 * @args: args array
 *
 */
2484
void __audit_socketcall(int nargs, unsigned long *args)
2485 2486 2487
{
	struct audit_context *context = current->audit_context;

A
Al Viro 已提交
2488 2489 2490
	context->type = AUDIT_SOCKETCALL;
	context->socketcall.nargs = nargs;
	memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2491 2492
}

A
Al Viro 已提交
2493 2494 2495 2496 2497 2498
/**
 * __audit_fd_pair - record audit data for pipe and socketpair
 * @fd1: the first file descriptor
 * @fd2: the second file descriptor
 *
 */
A
Al Viro 已提交
2499
void __audit_fd_pair(int fd1, int fd2)
A
Al Viro 已提交
2500 2501
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2502 2503
	context->fds[0] = fd1;
	context->fds[1] = fd2;
A
Al Viro 已提交
2504 2505
}

2506 2507 2508 2509 2510 2511 2512
/**
 * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto
 * @len: data length in user space
 * @a: data address in kernel space
 *
 * Returns 0 for success or NULL context or < 0 on error.
 */
2513
int __audit_sockaddr(int len, void *a)
2514 2515 2516
{
	struct audit_context *context = current->audit_context;

2517 2518 2519 2520 2521 2522
	if (!context->sockaddr) {
		void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
		if (!p)
			return -ENOMEM;
		context->sockaddr = p;
	}
2523

2524 2525
	context->sockaddr_len = len;
	memcpy(context->sockaddr, a, len);
2526 2527 2528
	return 0;
}

A
Al Viro 已提交
2529 2530 2531 2532 2533
void __audit_ptrace(struct task_struct *t)
{
	struct audit_context *context = current->audit_context;

	context->target_pid = t->pid;
2534
	context->target_auid = audit_get_loginuid(t);
2535
	context->target_uid = task_uid(t);
2536
	context->target_sessionid = audit_get_sessionid(t);
2537
	security_task_getsecid(t, &context->target_sid);
2538
	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
A
Al Viro 已提交
2539 2540
}

2541 2542 2543 2544 2545 2546 2547 2548
/**
 * audit_signal_info - record signal info for shutting down audit subsystem
 * @sig: signal value
 * @t: task being signaled
 *
 * If the audit subsystem is being terminated, record the task (pid)
 * and uid that is doing that.
 */
A
Amy Griffis 已提交
2549
int __audit_signal_info(int sig, struct task_struct *t)
2550
{
A
Amy Griffis 已提交
2551 2552 2553
	struct audit_aux_data_pids *axp;
	struct task_struct *tsk = current;
	struct audit_context *ctx = tsk->audit_context;
2554
	kuid_t uid = current_uid(), t_uid = task_uid(t);
2555

A
Al Viro 已提交
2556
	if (audit_pid && t->tgid == audit_pid) {
2557
		if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
A
Al Viro 已提交
2558
			audit_sig_pid = tsk->pid;
2559
			if (uid_valid(tsk->loginuid))
A
Al Viro 已提交
2560
				audit_sig_uid = tsk->loginuid;
A
Al Viro 已提交
2561
			else
2562
				audit_sig_uid = uid;
2563
			security_task_getsecid(tsk, &audit_sig_sid);
A
Al Viro 已提交
2564 2565 2566
		}
		if (!audit_signals || audit_dummy_context())
			return 0;
2567
	}
A
Amy Griffis 已提交
2568 2569 2570 2571 2572

	/* optimize the common case by putting first signal recipient directly
	 * in audit_context */
	if (!ctx->target_pid) {
		ctx->target_pid = t->tgid;
2573
		ctx->target_auid = audit_get_loginuid(t);
2574
		ctx->target_uid = t_uid;
2575
		ctx->target_sessionid = audit_get_sessionid(t);
2576
		security_task_getsecid(t, &ctx->target_sid);
2577
		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
A
Amy Griffis 已提交
2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590
		return 0;
	}

	axp = (void *)ctx->aux_pids;
	if (!axp || axp->pid_count == AUDIT_AUX_PIDS) {
		axp = kzalloc(sizeof(*axp), GFP_ATOMIC);
		if (!axp)
			return -ENOMEM;

		axp->d.type = AUDIT_OBJ_PID;
		axp->d.next = ctx->aux_pids;
		ctx->aux_pids = (void *)axp;
	}
2591
	BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
A
Amy Griffis 已提交
2592 2593

	axp->target_pid[axp->pid_count] = t->tgid;
2594
	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2595
	axp->target_uid[axp->pid_count] = t_uid;
2596
	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2597
	security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2598
	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
A
Amy Griffis 已提交
2599 2600 2601
	axp->pid_count++;

	return 0;
2602
}
S
Steve Grubb 已提交
2603

2604 2605
/**
 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
D
David Howells 已提交
2606 2607 2608
 * @bprm: pointer to the bprm being processed
 * @new: the proposed new credentials
 * @old: the old credentials
2609 2610 2611 2612 2613 2614
 *
 * Simply check if the proc already has the caps given by the file and if not
 * store the priv escalation info for later auditing at the end of the syscall
 *
 * -Eric
 */
D
David Howells 已提交
2615 2616
int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
			   const struct cred *new, const struct cred *old)
2617 2618 2619 2620 2621 2622 2623 2624
{
	struct audit_aux_data_bprm_fcaps *ax;
	struct audit_context *context = current->audit_context;
	struct cpu_vfs_cap_data vcaps;
	struct dentry *dentry;

	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
	if (!ax)
D
David Howells 已提交
2625
		return -ENOMEM;
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	ax->d.type = AUDIT_BPRM_FCAPS;
	ax->d.next = context->aux;
	context->aux = (void *)ax;

	dentry = dget(bprm->file->f_dentry);
	get_vfs_caps_from_disk(dentry, &vcaps);
	dput(dentry);

	ax->fcap.permitted = vcaps.permitted;
	ax->fcap.inheritable = vcaps.inheritable;
	ax->fcap.fE = !!(vcaps.magic_etc & VFS_CAP_FLAGS_EFFECTIVE);
	ax->fcap_ver = (vcaps.magic_etc & VFS_CAP_REVISION_MASK) >> VFS_CAP_REVISION_SHIFT;

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	ax->old_pcap.permitted   = old->cap_permitted;
	ax->old_pcap.inheritable = old->cap_inheritable;
	ax->old_pcap.effective   = old->cap_effective;
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	ax->new_pcap.permitted   = new->cap_permitted;
	ax->new_pcap.inheritable = new->cap_inheritable;
	ax->new_pcap.effective   = new->cap_effective;
	return 0;
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}

2650 2651
/**
 * __audit_log_capset - store information about the arguments to the capset syscall
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 * @pid: target pid of the capset call
 * @new: the new credentials
 * @old: the old (current) credentials
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 *
 * Record the aguments userspace sent to sys_capset for later printing by the
 * audit system if applicable
 */
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void __audit_log_capset(pid_t pid,
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		       const struct cred *new, const struct cred *old)
2661 2662
{
	struct audit_context *context = current->audit_context;
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	context->capset.pid = pid;
	context->capset.cap.effective   = new->cap_effective;
	context->capset.cap.inheritable = new->cap_effective;
	context->capset.cap.permitted   = new->cap_permitted;
	context->type = AUDIT_CAPSET;
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}

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void __audit_mmap_fd(int fd, int flags)
{
	struct audit_context *context = current->audit_context;
	context->mmap.fd = fd;
	context->mmap.flags = flags;
	context->type = AUDIT_MMAP;
}

2678 2679
static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
{
2680 2681
	kuid_t auid, uid;
	kgid_t gid;
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	unsigned int sessionid;

	auid = audit_get_loginuid(current);
	sessionid = audit_get_sessionid(current);
	current_uid_gid(&uid, &gid);

	audit_log_format(ab, "auid=%u uid=%u gid=%u ses=%u",
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			 from_kuid(&init_user_ns, auid),
			 from_kuid(&init_user_ns, uid),
			 from_kgid(&init_user_ns, gid),
			 sessionid);
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	audit_log_task_context(ab);
	audit_log_format(ab, " pid=%d comm=", current->pid);
	audit_log_untrustedstring(ab, current->comm);
	audit_log_format(ab, " reason=");
	audit_log_string(ab, reason);
	audit_log_format(ab, " sig=%ld", signr);
}
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/**
 * audit_core_dumps - record information about processes that end abnormally
2702
 * @signr: signal value
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 *
 * If a process ends with a core dump, something fishy is going on and we
 * should record the event for investigation.
 */
void audit_core_dumps(long signr)
{
	struct audit_buffer *ab;

	if (!audit_enabled)
		return;

	if (signr == SIGQUIT)	/* don't care for those */
		return;

	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2718 2719 2720
	audit_log_abend(ab, "memory violation", signr);
	audit_log_end(ab);
}
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2722
void __audit_seccomp(unsigned long syscall, long signr, int code)
2723 2724 2725 2726
{
	struct audit_buffer *ab;

	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_ANOM_ABEND);
2727
	audit_log_abend(ab, "seccomp", signr);
2728
	audit_log_format(ab, " syscall=%ld", syscall);
2729 2730 2731
	audit_log_format(ab, " compat=%d", is_compat_task());
	audit_log_format(ab, " ip=0x%lx", KSTK_EIP(current));
	audit_log_format(ab, " code=0x%x", code);
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	audit_log_end(ab);
}
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struct list_head *audit_killed_trees(void)
{
	struct audit_context *ctx = current->audit_context;
	if (likely(!ctx || !ctx->in_syscall))
		return NULL;
	return &ctx->killed_trees;
}