auditsc.c 72.3 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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586
/* 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.
 */
L
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593
static int audit_filter_rules(struct task_struct *tsk,
594
			      struct audit_krule *rule,
L
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595
			      struct audit_context *ctx,
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596
			      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);

L
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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);
L
Linus Torvalds 已提交
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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619
				result = audit_comparator(ctx->ppid, f->op, f->val);
A
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620
			}
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621
			break;
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622
		case AUDIT_UID:
623
			result = audit_uid_comparator(cred->uid, f->op, f->uid);
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624 625
			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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630 631
			break;
		case AUDIT_FSUID:
632
			result = audit_uid_comparator(cred->fsuid, f->op, f->uid);
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633 634
			break;
		case AUDIT_GID:
635
			result = audit_gid_comparator(cred->gid, f->op, f->gid);
636 637 638 639 640 641 642
			if (f->op == Audit_equal) {
				if (!result)
					result = in_group_p(f->gid);
			} else if (f->op == Audit_not_equal) {
				if (result)
					result = !in_group_p(f->gid);
			}
L
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643 644
			break;
		case AUDIT_EGID:
645
			result = audit_gid_comparator(cred->egid, f->op, f->gid);
646 647 648 649 650 651 652
			if (f->op == Audit_equal) {
				if (!result)
					result = in_egroup_p(f->gid);
			} else if (f->op == Audit_not_equal) {
				if (result)
					result = !in_egroup_p(f->gid);
			}
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			break;
		case AUDIT_SGID:
655
			result = audit_gid_comparator(cred->sgid, f->op, f->gid);
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			break;
		case AUDIT_FSGID:
658
			result = audit_gid_comparator(cred->fsgid, f->op, f->gid);
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			break;
		case AUDIT_PERS:
661
			result = audit_comparator(tsk->personality, f->op, f->val);
L
Linus Torvalds 已提交
662
			break;
663
		case AUDIT_ARCH:
D
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664
			if (ctx)
665
				result = audit_comparator(ctx->arch, f->op, f->val);
666
			break;
L
Linus Torvalds 已提交
667 668 669

		case AUDIT_EXIT:
			if (ctx && ctx->return_valid)
670
				result = audit_comparator(ctx->return_code, f->op, f->val);
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671 672
			break;
		case AUDIT_SUCCESS:
673
			if (ctx && ctx->return_valid) {
674 675
				if (f->val)
					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS);
676
				else
677
					result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE);
678
			}
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679 680
			break;
		case AUDIT_DEVMAJOR:
681 682 683 684 685
			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) {
686
				list_for_each_entry(n, &ctx->names_list, list) {
687 688
					if (audit_comparator(MAJOR(n->dev), f->op, f->val) ||
					    audit_comparator(MAJOR(n->rdev), f->op, f->val)) {
L
Linus Torvalds 已提交
689 690 691 692 693 694 695
						++result;
						break;
					}
				}
			}
			break;
		case AUDIT_DEVMINOR:
696 697 698 699 700
			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) {
701
				list_for_each_entry(n, &ctx->names_list, list) {
702 703
					if (audit_comparator(MINOR(n->dev), f->op, f->val) ||
					    audit_comparator(MINOR(n->rdev), f->op, f->val)) {
L
Linus Torvalds 已提交
704 705 706 707 708 709 710
						++result;
						break;
					}
				}
			}
			break;
		case AUDIT_INODE:
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Amy Griffis 已提交
711
			if (name)
712
				result = (name->ino == f->val);
A
Amy Griffis 已提交
713
			else if (ctx) {
714 715
				list_for_each_entry(n, &ctx->names_list, list) {
					if (audit_comparator(n->ino, f->op, f->val)) {
L
Linus Torvalds 已提交
716 717 718 719 720 721
						++result;
						break;
					}
				}
			}
			break;
E
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722 723
		case AUDIT_OBJ_UID:
			if (name) {
724
				result = audit_uid_comparator(name->uid, f->op, f->uid);
E
Eric Paris 已提交
725 726
			} else if (ctx) {
				list_for_each_entry(n, &ctx->names_list, list) {
727
					if (audit_uid_comparator(n->uid, f->op, f->uid)) {
E
Eric Paris 已提交
728 729 730 731 732 733
						++result;
						break;
					}
				}
			}
			break;
734 735
		case AUDIT_OBJ_GID:
			if (name) {
736
				result = audit_gid_comparator(name->gid, f->op, f->gid);
737 738
			} else if (ctx) {
				list_for_each_entry(n, &ctx->names_list, list) {
739
					if (audit_gid_comparator(n->gid, f->op, f->gid)) {
740 741 742 743 744 745
						++result;
						break;
					}
				}
			}
			break;
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Amy Griffis 已提交
746
		case AUDIT_WATCH:
747 748
			if (name)
				result = audit_watch_compare(rule->watch, name->ino, name->dev);
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Amy Griffis 已提交
749
			break;
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750 751 752 753
		case AUDIT_DIR:
			if (ctx)
				result = match_tree_refs(ctx, rule->tree);
			break;
L
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754 755 756
		case AUDIT_LOGINUID:
			result = 0;
			if (ctx)
757
				result = audit_uid_comparator(tsk->loginuid, f->op, f->uid);
L
Linus Torvalds 已提交
758
			break;
759 760 761 762 763
		case AUDIT_SUBJ_USER:
		case AUDIT_SUBJ_ROLE:
		case AUDIT_SUBJ_TYPE:
		case AUDIT_SUBJ_SEN:
		case AUDIT_SUBJ_CLR:
764 765 766 767 768
			/* 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 */
769
			if (f->lsm_rule) {
S
Steve Grubb 已提交
770
				if (need_sid) {
771
					security_task_getsecid(tsk, &sid);
S
Steve Grubb 已提交
772 773
					need_sid = 0;
				}
774
				result = security_audit_rule_match(sid, f->type,
775
				                                  f->op,
776
				                                  f->lsm_rule,
777
				                                  ctx);
S
Steve Grubb 已提交
778
			}
779
			break;
780 781 782 783 784 785 786
		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 */
787
			if (f->lsm_rule) {
788 789
				/* Find files that match */
				if (name) {
790
					result = security_audit_rule_match(
791
					           name->osid, f->type, f->op,
792
					           f->lsm_rule, ctx);
793
				} else if (ctx) {
794 795 796 797
					list_for_each_entry(n, &ctx->names_list, list) {
						if (security_audit_rule_match(n->osid, f->type,
									      f->op, f->lsm_rule,
									      ctx)) {
798 799 800 801 802 803
							++result;
							break;
						}
					}
				}
				/* Find ipc objects that match */
A
Al Viro 已提交
804 805 806 807 808 809
				if (!ctx || ctx->type != AUDIT_IPC)
					break;
				if (security_audit_rule_match(ctx->ipc.osid,
							      f->type, f->op,
							      f->lsm_rule, ctx))
					++result;
810 811
			}
			break;
L
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812 813 814 815 816
		case AUDIT_ARG0:
		case AUDIT_ARG1:
		case AUDIT_ARG2:
		case AUDIT_ARG3:
			if (ctx)
817
				result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val);
L
Linus Torvalds 已提交
818
			break;
A
Amy Griffis 已提交
819 820 821 822
		case AUDIT_FILTERKEY:
			/* ignore this field for filtering */
			result = 1;
			break;
A
Al Viro 已提交
823 824 825
		case AUDIT_PERM:
			result = audit_match_perm(ctx, f->val);
			break;
A
Al Viro 已提交
826 827 828
		case AUDIT_FILETYPE:
			result = audit_match_filetype(ctx, f->val);
			break;
829 830 831
		case AUDIT_FIELD_COMPARE:
			result = audit_field_compare(tsk, cred, f, ctx, name);
			break;
L
Linus Torvalds 已提交
832
		}
833
		if (!result)
L
Linus Torvalds 已提交
834 835
			return 0;
	}
836 837 838 839 840 841 842 843 844 845

	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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846 847 848 849 850 851 852 853 854 855 856
	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.
 */
857
static enum audit_state audit_filter_task(struct task_struct *tsk, char **key)
L
Linus Torvalds 已提交
858 859 860 861 862
{
	struct audit_entry *e;
	enum audit_state   state;

	rcu_read_lock();
863
	list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TASK], list) {
864 865
		if (audit_filter_rules(tsk, &e->rule, NULL, NULL,
				       &state, true)) {
866 867
			if (state == AUDIT_RECORD_CONTEXT)
				*key = kstrdup(e->rule.filterkey, GFP_ATOMIC);
L
Linus Torvalds 已提交
868 869 870 871 872 873 874 875 876 877
			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
878
 * also not high enough that we already know we have to write an audit
879
 * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT).
L
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880 881 882 883 884 885
 */
static enum audit_state audit_filter_syscall(struct task_struct *tsk,
					     struct audit_context *ctx,
					     struct list_head *list)
{
	struct audit_entry *e;
886
	enum audit_state state;
L
Linus Torvalds 已提交
887

888
	if (audit_pid && tsk->tgid == audit_pid)
889 890
		return AUDIT_DISABLED;

L
Linus Torvalds 已提交
891
	rcu_read_lock();
892
	if (!list_empty(list)) {
893 894 895 896
		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
897 898
			if ((e->rule.mask[word] & bit) == bit &&
			    audit_filter_rules(tsk, &e->rule, ctx, NULL,
899
					       &state, false)) {
A
Amy Griffis 已提交
900
				rcu_read_unlock();
901
				ctx->current_state = state;
A
Amy Griffis 已提交
902 903 904 905 906 907 908 909
				return state;
			}
		}
	}
	rcu_read_unlock();
	return AUDIT_BUILD_CONTEXT;
}

910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940
/*
 * 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
941
 * collected during syscall processing.  We only check rules in sublists at hash
942
 * buckets applicable to the inode numbers in audit_names.
A
Amy Griffis 已提交
943 944
 * Regarding audit_state, same rules apply as for audit_filter_syscall().
 */
945
void audit_filter_inodes(struct task_struct *tsk, struct audit_context *ctx)
A
Amy Griffis 已提交
946
{
947
	struct audit_names *n;
A
Amy Griffis 已提交
948 949

	if (audit_pid && tsk->tgid == audit_pid)
950
		return;
A
Amy Griffis 已提交
951 952 953

	rcu_read_lock();

954 955 956
	list_for_each_entry(n, &ctx->names_list, list) {
		if (audit_filter_inode_name(tsk, n, ctx))
			break;
957 958 959 960
	}
	rcu_read_unlock();
}

L
Linus Torvalds 已提交
961 962
static inline struct audit_context *audit_get_context(struct task_struct *tsk,
						      int return_valid,
963
						      long return_code)
L
Linus Torvalds 已提交
964 965 966
{
	struct audit_context *context = tsk->audit_context;

967
	if (!context)
L
Linus Torvalds 已提交
968 969
		return NULL;
	context->return_valid = return_valid;
E
Eric Paris 已提交
970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987

	/*
	 * 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
Linus Torvalds 已提交
988

989 990 991
	if (context->in_syscall && !context->dummy) {
		audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_EXIT]);
		audit_filter_inodes(tsk, context);
L
Linus Torvalds 已提交
992 993 994 995 996 997 998 999
	}

	tsk->audit_context = NULL;
	return context;
}

static inline void audit_free_names(struct audit_context *context)
{
1000
	struct audit_names *n, *next;
L
Linus Torvalds 已提交
1001 1002

#if AUDIT_DEBUG == 2
1003
	if (context->put_count + context->ino_count != context->name_count) {
1004
		printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
L
Linus Torvalds 已提交
1005 1006
		       " name_count=%d put_count=%d"
		       " ino_count=%d [NOT freeing]\n",
1007
		       __FILE__, __LINE__,
L
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1008 1009 1010
		       context->serial, context->major, context->in_syscall,
		       context->name_count, context->put_count,
		       context->ino_count);
1011
		list_for_each_entry(n, &context->names_list, list) {
L
Linus Torvalds 已提交
1012
			printk(KERN_ERR "names[%d] = %p = %s\n", i,
1013
			       n->name, n->name->name ?: "(null)");
1014
		}
L
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1015 1016 1017 1018 1019 1020 1021 1022 1023
		dump_stack();
		return;
	}
#endif
#if AUDIT_DEBUG
	context->put_count  = 0;
	context->ino_count  = 0;
#endif

1024 1025 1026
	list_for_each_entry_safe(n, next, &context->names_list, list) {
		list_del(&n->list);
		if (n->name && n->name_put)
1027
			final_putname(n->name);
1028 1029
		if (n->should_free)
			kfree(n);
1030
	}
L
Linus Torvalds 已提交
1031
	context->name_count = 0;
1032 1033 1034
	path_put(&context->pwd);
	context->pwd.dentry = NULL;
	context->pwd.mnt = NULL;
L
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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
1045 1046 1047 1048
	while ((aux = context->aux_pids)) {
		context->aux_pids = aux->next;
		kfree(aux);
	}
L
Linus Torvalds 已提交
1049 1050 1051 1052 1053 1054 1055
}

static inline void audit_zero_context(struct audit_context *context,
				      enum audit_state state)
{
	memset(context, 0, sizeof(*context));
	context->state      = state;
1056
	context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
L
Linus Torvalds 已提交
1057 1058 1059 1060 1061 1062 1063 1064 1065
}

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
1066
	INIT_LIST_HEAD(&context->killed_trees);
1067
	INIT_LIST_HEAD(&context->names_list);
L
Linus Torvalds 已提交
1068 1069 1070
	return context;
}

1071 1072 1073 1074 1075
/**
 * 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
1076 1077
 * if necessary.  Doing so turns on system call auditing for the
 * specified task.  This is called from copy_process, so no lock is
1078 1079
 * needed.
 */
L
Linus Torvalds 已提交
1080 1081 1082 1083
int audit_alloc(struct task_struct *tsk)
{
	struct audit_context *context;
	enum audit_state     state;
1084
	char *key = NULL;
L
Linus Torvalds 已提交
1085

1086
	if (likely(!audit_ever_enabled))
L
Linus Torvalds 已提交
1087 1088
		return 0; /* Return if not auditing. */

1089
	state = audit_filter_task(tsk, &key);
1090
	if (state == AUDIT_DISABLED)
L
Linus Torvalds 已提交
1091 1092 1093
		return 0;

	if (!(context = audit_alloc_context(state))) {
1094
		kfree(key);
L
Linus Torvalds 已提交
1095 1096 1097
		audit_log_lost("out of memory in audit_alloc");
		return -ENOMEM;
	}
1098
	context->filterkey = key;
L
Linus Torvalds 已提交
1099 1100 1101 1102 1103 1104 1105 1106

	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
1107 1108 1109 1110 1111 1112 1113
	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
1114 1115
}

J
Joy Latten 已提交
1116
void audit_log_task_context(struct audit_buffer *ab)
1117 1118
{
	char *ctx = NULL;
1119 1120 1121 1122
	unsigned len;
	int error;
	u32 sid;

1123
	security_task_getsecid(current, &sid);
1124 1125
	if (!sid)
		return;
1126

1127
	error = security_secid_to_secctx(sid, &ctx, &len);
1128 1129
	if (error) {
		if (error != -EINVAL)
1130 1131 1132 1133 1134
			goto error_path;
		return;
	}

	audit_log_format(ab, " subj=%s", ctx);
1135
	security_release_secctx(ctx, len);
1136
	return;
1137 1138

error_path:
1139
	audit_panic("error in audit_log_task_context");
1140 1141 1142
	return;
}

J
Joy Latten 已提交
1143 1144
EXPORT_SYMBOL(audit_log_task_context);

P
Peter Moody 已提交
1145
void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
1146
{
P
Peter Moody 已提交
1147
	const struct cred *cred;
1148 1149
	char name[sizeof(tsk->comm)];
	struct mm_struct *mm = tsk->mm;
P
Peter Moody 已提交
1150 1151 1152 1153
	char *tty;

	if (!ab)
		return;
1154

1155
	/* tsk == current */
P
Peter Moody 已提交
1156 1157 1158
	cred = current_cred();

	spin_lock_irq(&tsk->sighand->siglock);
A
Alan Cox 已提交
1159
	if (tsk->signal && tsk->signal->tty)
P
Peter Moody 已提交
1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171
		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,
1172 1173 1174 1175 1176 1177 1178 1179 1180
			 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
1181
			 tsk->sessionid, tty);
1182

1183
	get_task_comm(name, tsk);
1184 1185
	audit_log_format(ab, " comm=");
	audit_log_untrustedstring(ab, name);
1186

1187 1188
	if (mm) {
		down_read(&mm->mmap_sem);
1189 1190
		if (mm->exe_file)
			audit_log_d_path(ab, " exe=", &mm->exe_file->f_path);
1191
		up_read(&mm->mmap_sem);
1192
	}
1193
	audit_log_task_context(ab);
1194 1195
}

P
Peter Moody 已提交
1196 1197
EXPORT_SYMBOL(audit_log_task_info);

A
Amy Griffis 已提交
1198
static int audit_log_pid_context(struct audit_context *context, pid_t pid,
1199
				 kuid_t auid, kuid_t uid, unsigned int sessionid,
1200
				 u32 sid, char *comm)
A
Amy Griffis 已提交
1201 1202
{
	struct audit_buffer *ab;
1203
	char *ctx = NULL;
A
Amy Griffis 已提交
1204 1205 1206 1207 1208
	u32 len;
	int rc = 0;

	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
	if (!ab)
1209
		return rc;
A
Amy Griffis 已提交
1210

1211 1212
	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
			 from_kuid(&init_user_ns, auid),
1213
			 from_kuid(&init_user_ns, uid), sessionid);
1214
	if (security_secid_to_secctx(sid, &ctx, &len)) {
1215
		audit_log_format(ab, " obj=(none)");
A
Amy Griffis 已提交
1216
		rc = 1;
1217 1218 1219 1220
	} else {
		audit_log_format(ab, " obj=%s", ctx);
		security_release_secctx(ctx, len);
	}
1221 1222
	audit_log_format(ab, " ocomm=");
	audit_log_untrustedstring(ab, comm);
A
Amy Griffis 已提交
1223 1224 1225 1226 1227
	audit_log_end(ab);

	return rc;
}

1228 1229 1230
/*
 * 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
1231
 * within about 500 bytes (next page boundary)
1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244
 *
 * 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
1245
{
1246 1247
	char arg_num_len_buf[12];
	const char __user *tmp_p = p;
1248 1249
	/* 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;
1250 1251 1252 1253 1254 1255 1256
	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
1257

1258 1259 1260 1261 1262 1263
	/*
	 * 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.
	 */
1264
	if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1265 1266
		WARN_ON(1);
		send_sig(SIGKILL, current, 0);
1267
		return -1;
1268
	}
1269

1270 1271 1272 1273 1274 1275 1276
	/* 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
1277
		/*
1278 1279 1280
		 * 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
1281
		 */
1282
		if (ret) {
P
Peter Zijlstra 已提交
1283 1284
			WARN_ON(1);
			send_sig(SIGKILL, current, 0);
1285
			return -1;
P
Peter Zijlstra 已提交
1286
		}
1287 1288 1289 1290 1291 1292 1293 1294
		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
1295 1296
			break;
		}
1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327
		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
1328 1329

		/*
1330 1331 1332 1333
		 * first record needs to say how long the original string was
		 * so we can be sure nothing was lost.
		 */
		if ((i == 0) && (too_long))
1334
			audit_log_format(*ab, " a%d_len=%zu", arg_num,
1335 1336 1337 1338 1339 1340
					 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
1341
		 */
1342 1343 1344 1345
		if (len >= max_execve_audit_len)
			ret = copy_from_user(buf, p, to_send);
		else
			ret = 0;
1346
		if (ret) {
P
Peter Zijlstra 已提交
1347 1348
			WARN_ON(1);
			send_sig(SIGKILL, current, 0);
1349
			return -1;
P
Peter Zijlstra 已提交
1350
		}
1351 1352 1353
		buf[to_send] = '\0';

		/* actually log it */
1354
		audit_log_format(*ab, " a%d", arg_num);
1355 1356 1357 1358
		if (too_long)
			audit_log_format(*ab, "[%d]", i);
		audit_log_format(*ab, "=");
		if (has_cntl)
1359
			audit_log_n_hex(*ab, buf, to_send);
1360
		else
1361
			audit_log_string(*ab, buf);
1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378

		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)
{
1379 1380
	int i, len;
	size_t len_sent = 0;
1381 1382
	const char __user *p;
	char *buf;
P
Peter Zijlstra 已提交
1383

1384 1385 1386 1387
	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
1388

1389
	audit_log_format(*ab, "argc=%d", axi->argc);
1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400

	/*
	 * 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
1401
	}
1402 1403 1404 1405 1406 1407 1408 1409 1410

	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
1411 1412
}

1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441
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
1442
static void show_special(struct audit_context *context, int *call_panic)
A
Al Viro 已提交
1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458
{
	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
1459 1460 1461
	case AUDIT_IPC: {
		u32 osid = context->ipc.osid;

A
Al Viro 已提交
1462
		audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
1463 1464 1465
				 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
1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476
		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
1477 1478 1479 1480
		if (context->ipc.has_perm) {
			audit_log_end(ab);
			ab = audit_log_start(context, GFP_KERNEL,
					     AUDIT_IPC_SET_PERM);
1481 1482
			if (unlikely(!ab))
				return;
A
Al Viro 已提交
1483
			audit_log_format(ab,
A
Al Viro 已提交
1484
				"qbytes=%lx ouid=%u ogid=%u mode=%#ho",
A
Al Viro 已提交
1485 1486 1487 1488 1489
				context->ipc.qbytes,
				context->ipc.perm_uid,
				context->ipc.perm_gid,
				context->ipc.perm_mode);
		}
A
Al Viro 已提交
1490
		break; }
A
Al Viro 已提交
1491 1492
	case AUDIT_MQ_OPEN: {
		audit_log_format(ab,
A
Al Viro 已提交
1493
			"oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
A
Al Viro 已提交
1494 1495 1496 1497 1498 1499 1500
			"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
1501 1502 1503 1504 1505 1506 1507 1508 1509 1510
	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
1511 1512 1513 1514 1515
	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
1516 1517 1518 1519 1520 1521 1522 1523 1524
	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
1525 1526 1527 1528 1529 1530
	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
1531 1532 1533 1534
	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
1535 1536 1537 1538
	}
	audit_log_end(ab);
}

1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553
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=");
1554
			audit_log_untrustedstring(ab, n->name->name);
1555 1556 1557 1558
			break;
		case 0:
			/* name was specified as a relative path and the
			 * directory component is the cwd */
1559
			audit_log_d_path(ab, " name=", &context->pwd);
1560 1561 1562 1563
			break;
		default:
			/* log the name's directory component */
			audit_log_format(ab, " name=");
1564
			audit_log_n_untrustedstring(ab, n->name->name,
1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577
						    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,
1578 1579
				 from_kuid(&init_user_ns, n->uid),
				 from_kgid(&init_user_ns, n->gid),
1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600
				 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);
}

1601
static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
L
Linus Torvalds 已提交
1602
{
S
Steve Grubb 已提交
1603
	int i, call_panic = 0;
L
Linus Torvalds 已提交
1604
	struct audit_buffer *ab;
1605
	struct audit_aux_data *aux;
1606
	struct audit_names *n;
L
Linus Torvalds 已提交
1607

1608
	/* tsk == current */
1609
	context->personality = tsk->personality;
1610 1611

	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
L
Linus Torvalds 已提交
1612 1613
	if (!ab)
		return;		/* audit_panic has been called */
1614 1615
	audit_log_format(ab, "arch=%x syscall=%d",
			 context->arch, context->major);
L
Linus Torvalds 已提交
1616 1617 1618
	if (context->personality != PER_LINUX)
		audit_log_format(ab, " per=%lx", context->personality);
	if (context->return_valid)
D
Daniel Walker 已提交
1619
		audit_log_format(ab, " success=%s exit=%ld",
1620 1621
				 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
				 context->return_code);
A
Alan Cox 已提交
1622

L
Linus Torvalds 已提交
1623
	audit_log_format(ab,
P
Peter Moody 已提交
1624 1625 1626 1627 1628 1629
			 " 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
1630

1631
	audit_log_task_info(ab, tsk);
1632
	audit_log_key(ab, context->filterkey);
L
Linus Torvalds 已提交
1633 1634
	audit_log_end(ab);

1635
	for (aux = context->aux; aux; aux = aux->next) {
1636

1637
		ab = audit_log_start(context, GFP_KERNEL, aux->type);
L
Linus Torvalds 已提交
1638 1639 1640 1641
		if (!ab)
			continue; /* audit_panic has been called */

		switch (aux->type) {
1642

A
Al Viro 已提交
1643 1644
		case AUDIT_EXECVE: {
			struct audit_aux_data_execve *axi = (void *)aux;
1645
			audit_log_execve_info(context, &ab, axi);
A
Al Viro 已提交
1646
			break; }
S
Steve Grubb 已提交
1647

1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661
		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
1662 1663 1664 1665
		}
		audit_log_end(ab);
	}

A
Al Viro 已提交
1666
	if (context->type)
A
Al Viro 已提交
1667
		show_special(context, &call_panic);
A
Al Viro 已提交
1668

A
Al Viro 已提交
1669 1670 1671 1672 1673 1674 1675 1676 1677
	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);
		}
	}

1678 1679 1680 1681 1682 1683 1684 1685 1686 1687
	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
1688 1689 1690 1691 1692
	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],
1693 1694
						  axs->target_auid[i],
						  axs->target_uid[i],
1695
						  axs->target_sessionid[i],
1696 1697
						  axs->target_sid[i],
						  axs->target_comm[i]))
A
Amy Griffis 已提交
1698
				call_panic = 1;
A
Al Viro 已提交
1699 1700
	}

A
Amy Griffis 已提交
1701 1702
	if (context->target_pid &&
	    audit_log_pid_context(context, context->target_pid,
1703
				  context->target_auid, context->target_uid,
1704
				  context->target_sessionid,
1705
				  context->target_sid, context->target_comm))
A
Amy Griffis 已提交
1706 1707
			call_panic = 1;

1708
	if (context->pwd.dentry && context->pwd.mnt) {
1709
		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1710
		if (ab) {
1711
			audit_log_d_path(ab, " cwd=", &context->pwd);
1712 1713 1714
			audit_log_end(ab);
		}
	}
1715

1716 1717 1718
	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
1719 1720 1721 1722 1723

	/* 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
1724 1725
	if (call_panic)
		audit_panic("error converting sid to string");
L
Linus Torvalds 已提交
1726 1727
}

1728 1729 1730 1731
/**
 * audit_free - free a per-task audit context
 * @tsk: task whose audit context block to free
 *
1732
 * Called from copy_process and do_exit
1733
 */
1734
void __audit_free(struct task_struct *tsk)
L
Linus Torvalds 已提交
1735 1736 1737 1738
{
	struct audit_context *context;

	context = audit_get_context(tsk, 0, 0);
1739
	if (!context)
L
Linus Torvalds 已提交
1740 1741 1742
		return;

	/* Check for system calls that do not go through the exit
D
Daniel Walker 已提交
1743 1744
	 * function (e.g., exit_group), then free context block.
	 * We use GFP_ATOMIC here because we might be doing this
1745
	 * in the context of the idle thread */
1746
	/* that can happen only if we are called from do_exit() */
1747
	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1748
		audit_log_exit(context, tsk);
A
Al Viro 已提交
1749 1750
	if (!list_empty(&context->killed_trees))
		audit_kill_trees(&context->killed_trees);
L
Linus Torvalds 已提交
1751 1752 1753 1754

	audit_free_context(context);
}

1755 1756 1757 1758 1759 1760 1761 1762 1763 1764
/**
 * 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
1765 1766 1767 1768 1769
 * 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
1770 1771
 * be written).
 */
1772
void __audit_syscall_entry(int arch, int major,
L
Linus Torvalds 已提交
1773 1774 1775
			 unsigned long a1, unsigned long a2,
			 unsigned long a3, unsigned long a4)
{
1776
	struct task_struct *tsk = current;
L
Linus Torvalds 已提交
1777 1778 1779
	struct audit_context *context = tsk->audit_context;
	enum audit_state     state;

1780
	if (!context)
R
Roland McGrath 已提交
1781
		return;
L
Linus Torvalds 已提交
1782 1783 1784 1785 1786 1787

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

	if (!audit_enabled)
		return;

1788
	context->arch	    = arch;
L
Linus Torvalds 已提交
1789 1790 1791 1792 1793 1794 1795
	context->major      = major;
	context->argv[0]    = a1;
	context->argv[1]    = a2;
	context->argv[2]    = a3;
	context->argv[3]    = a4;

	state = context->state;
1796
	context->dummy = !audit_n_rules;
1797 1798
	if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
		context->prio = 0;
1799
		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1800
	}
1801
	if (state == AUDIT_DISABLED)
L
Linus Torvalds 已提交
1802 1803
		return;

1804
	context->serial     = 0;
L
Linus Torvalds 已提交
1805 1806
	context->ctime      = CURRENT_TIME;
	context->in_syscall = 1;
1807
	context->current_state  = state;
A
Alexander Viro 已提交
1808
	context->ppid       = 0;
L
Linus Torvalds 已提交
1809 1810
}

1811 1812
/**
 * audit_syscall_exit - deallocate audit context after a system call
1813 1814
 * @success: success value of the syscall
 * @return_code: return value of the syscall
1815 1816
 *
 * Tear down after system call.  If the audit context has been marked as
L
Linus Torvalds 已提交
1817
 * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1818
 * filtering, or because some other part of the kernel wrote an audit
L
Linus Torvalds 已提交
1819
 * message), then write out the syscall information.  In call cases,
1820 1821
 * free the names stored from getname().
 */
1822
void __audit_syscall_exit(int success, long return_code)
L
Linus Torvalds 已提交
1823
{
1824
	struct task_struct *tsk = current;
L
Linus Torvalds 已提交
1825 1826
	struct audit_context *context;

1827 1828 1829 1830
	if (success)
		success = AUDITSC_SUCCESS;
	else
		success = AUDITSC_FAILURE;
L
Linus Torvalds 已提交
1831

1832
	context = audit_get_context(tsk, success, return_code);
1833
	if (!context)
1834
		return;
L
Linus Torvalds 已提交
1835

1836
	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1837
		audit_log_exit(context, tsk);
L
Linus Torvalds 已提交
1838 1839

	context->in_syscall = 0;
1840
	context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1841

A
Al Viro 已提交
1842 1843 1844
	if (!list_empty(&context->killed_trees))
		audit_kill_trees(&context->killed_trees);

A
Al Viro 已提交
1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857
	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
1858
	}
A
Al Viro 已提交
1859
	tsk->audit_context = context;
L
Linus Torvalds 已提交
1860 1861
}

A
Al Viro 已提交
1862 1863 1864 1865 1866 1867 1868
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;
1869
	if (likely(hlist_empty(&inode->i_fsnotify_marks)))
A
Al Viro 已提交
1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881
		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
1882
		printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
A
Al Viro 已提交
1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911
		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;
1912
		if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) {
A
Al Viro 已提交
1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941
			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
1942
			"out of memory, audit has lost a tree reference\n");
A
Al Viro 已提交
1943 1944 1945 1946 1947 1948 1949 1950
		unroll_tree_refs(context, p, count);
		audit_set_auditable(context);
		return;
	}
	rcu_read_unlock();
#endif
}

1951 1952
static struct audit_names *audit_alloc_name(struct audit_context *context,
						unsigned char type)
1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966
{
	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;
1967
	aname->type = type;
1968 1969 1970 1971 1972 1973 1974 1975 1976
	list_add_tail(&aname->list, &context->names_list);

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

1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999
/**
 * 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;
}

2000 2001 2002 2003 2004 2005 2006
/**
 * 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().
 */
2007
void __audit_getname(struct filename *name)
L
Linus Torvalds 已提交
2008 2009
{
	struct audit_context *context = current->audit_context;
2010
	struct audit_names *n;
L
Linus Torvalds 已提交
2011 2012 2013 2014 2015 2016 2017 2018 2019

	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;
	}
2020

2021 2022 2023 2024 2025
#if AUDIT_DEBUG
	/* The filename _must_ have a populated ->name */
	BUG_ON(!name->name);
#endif

2026
	n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
2027 2028 2029 2030 2031 2032
	if (!n)
		return;

	n->name = name;
	n->name_len = AUDIT_NAME_FULL;
	n->name_put = true;
2033
	name->aname = n;
2034

2035 2036
	if (!context->pwd.dentry)
		get_fs_pwd(current->fs, &context->pwd);
L
Linus Torvalds 已提交
2037 2038
}

2039 2040 2041 2042 2043 2044 2045
/* 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().
 */
2046
void audit_putname(struct filename *name)
L
Linus Torvalds 已提交
2047 2048 2049 2050 2051 2052
{
	struct audit_context *context = current->audit_context;

	BUG_ON(!context);
	if (!context->in_syscall) {
#if AUDIT_DEBUG == 2
2053
		printk(KERN_ERR "%s:%d(:%d): final_putname(%p)\n",
L
Linus Torvalds 已提交
2054 2055
		       __FILE__, __LINE__, context->serial, name);
		if (context->name_count) {
2056
			struct audit_names *n;
L
Linus Torvalds 已提交
2057
			int i;
2058 2059

			list_for_each_entry(n, &context->names_list, list)
L
Linus Torvalds 已提交
2060
				printk(KERN_ERR "name[%d] = %p = %s\n", i,
2061
				       n->name, n->name->name ?: "(null)");
2062
			}
L
Linus Torvalds 已提交
2063
#endif
2064
		final_putname(name);
L
Linus Torvalds 已提交
2065 2066 2067 2068 2069 2070 2071 2072 2073 2074
	}
#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,
2075 2076
			       context->in_syscall, name->name,
			       context->name_count, context->put_count);
L
Linus Torvalds 已提交
2077 2078 2079 2080 2081 2082
			dump_stack();
		}
	}
#endif
}

2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103
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;
}


2104
/* Copy inode data into an audit_names. */
2105 2106
static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
			     const struct inode *inode)
2107
{
2108 2109 2110 2111 2112 2113
	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;
2114
	security_inode_getsecid(inode, &name->osid);
2115
	audit_copy_fcaps(name, dentry);
2116 2117
}

2118
/**
2119
 * __audit_inode - store the inode and device from a lookup
2120
 * @name: name being audited
2121
 * @dentry: dentry being audited
2122
 * @parent: does this dentry represent the parent?
2123
 */
2124
void __audit_inode(struct filename *name, const struct dentry *dentry,
2125
		   unsigned int parent)
L
Linus Torvalds 已提交
2126 2127
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2128
	const struct inode *inode = dentry->d_inode;
2129
	struct audit_names *n;
L
Linus Torvalds 已提交
2130 2131 2132

	if (!context->in_syscall)
		return;
2133

2134 2135 2136
	if (!name)
		goto out_alloc;

2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156
#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;
		}
	}

2157
	list_for_each_entry_reverse(n, &context->names_list, list) {
2158
		/* does the name pointer match? */
2159
		if (!n->name || n->name->name != name->name)
2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170
			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
2171
	}
2172

2173
out_alloc:
2174 2175 2176
	/* unable to find the name from a previous getname(). Allocate a new
	 * anonymous entry.
	 */
2177
	n = audit_alloc_name(context, AUDIT_TYPE_NORMAL);
2178 2179 2180
	if (!n)
		return;
out:
2181
	if (parent) {
2182
		n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL;
2183 2184 2185 2186 2187
		n->type = AUDIT_TYPE_PARENT;
	} else {
		n->name_len = AUDIT_NAME_FULL;
		n->type = AUDIT_TYPE_NORMAL;
	}
A
Al Viro 已提交
2188
	handle_path(dentry);
2189
	audit_copy_inode(n, dentry, inode);
2190 2191 2192
}

/**
2193
 * __audit_inode_child - collect inode info for created/removed objects
2194
 * @parent: inode of dentry parent
2195
 * @dentry: dentry being audited
2196
 * @type:   AUDIT_TYPE_* value that we're looking for
2197 2198 2199 2200 2201 2202 2203 2204 2205
 *
 * 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.
 */
2206
void __audit_inode_child(const struct inode *parent,
2207 2208
			 const struct dentry *dentry,
			 const unsigned char type)
2209 2210
{
	struct audit_context *context = current->audit_context;
2211
	const struct inode *inode = dentry->d_inode;
2212
	const char *dname = dentry->d_name.name;
2213
	struct audit_names *n, *found_parent = NULL, *found_child = NULL;
2214 2215 2216 2217

	if (!context->in_syscall)
		return;

A
Al Viro 已提交
2218 2219
	if (inode)
		handle_one(inode);
2220

2221
	/* look for a parent entry first */
2222
	list_for_each_entry(n, &context->names_list, list) {
2223
		if (!n->name || n->type != AUDIT_TYPE_PARENT)
A
Amy Griffis 已提交
2224 2225 2226
			continue;

		if (n->ino == parent->i_ino &&
2227
		    !audit_compare_dname_path(dname, n->name->name, n->name_len)) {
2228 2229
			found_parent = n;
			break;
A
Amy Griffis 已提交
2230
		}
A
Amy Griffis 已提交
2231
	}
2232

2233
	/* is there a matching child entry? */
2234
	list_for_each_entry(n, &context->names_list, list) {
2235 2236 2237 2238 2239 2240
		/* 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
2241 2242
			continue;

2243 2244
		if (!strcmp(dname, n->name->name) ||
		    !audit_compare_dname_path(dname, n->name->name,
2245 2246
						found_parent ?
						found_parent->name_len :
2247
						AUDIT_NAME_FULL)) {
2248 2249
			found_child = n;
			break;
A
Amy Griffis 已提交
2250
		}
S
Steve Grubb 已提交
2251
	}
A
Amy Griffis 已提交
2252 2253

	if (!found_parent) {
2254 2255
		/* create a new, "anonymous" parent record */
		n = audit_alloc_name(context, AUDIT_TYPE_PARENT);
2256
		if (!n)
S
Steve Grubb 已提交
2257
			return;
2258
		audit_copy_inode(n, NULL, parent);
2259
	}
A
Amy Griffis 已提交
2260 2261

	if (!found_child) {
2262 2263
		found_child = audit_alloc_name(context, type);
		if (!found_child)
A
Amy Griffis 已提交
2264 2265 2266 2267 2268 2269
			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) {
2270 2271
			found_child->name = found_parent->name;
			found_child->name_len = AUDIT_NAME_FULL;
A
Amy Griffis 已提交
2272
			/* don't call __putname() */
2273
			found_child->name_put = false;
A
Amy Griffis 已提交
2274 2275
		}
	}
2276 2277 2278 2279
	if (inode)
		audit_copy_inode(found_child, dentry, inode);
	else
		found_child->ino = (unsigned long)-1;
2280
}
2281
EXPORT_SYMBOL_GPL(__audit_inode_child);
2282

2283 2284 2285 2286 2287 2288 2289 2290
/**
 * 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.
 */
2291
int auditsc_get_stamp(struct audit_context *ctx,
2292
		       struct timespec *t, unsigned int *serial)
L
Linus Torvalds 已提交
2293
{
2294 2295
	if (!ctx->in_syscall)
		return 0;
2296 2297
	if (!ctx->serial)
		ctx->serial = audit_serial();
2298 2299 2300
	t->tv_sec  = ctx->ctime.tv_sec;
	t->tv_nsec = ctx->ctime.tv_nsec;
	*serial    = ctx->serial;
2301 2302 2303 2304
	if (!ctx->prio) {
		ctx->prio = 1;
		ctx->current_state = AUDIT_RECORD_CONTEXT;
	}
2305
	return 1;
L
Linus Torvalds 已提交
2306 2307
}

2308 2309 2310
/* global counter which is incremented every time something logs in */
static atomic_t session_id = ATOMIC_INIT(0);

2311
/**
2312
 * audit_set_loginuid - set current task's audit_context loginuid
2313 2314 2315 2316 2317 2318
 * @loginuid: loginuid value
 *
 * Returns 0.
 *
 * Called (set) from fs/proc/base.c::proc_loginuid_write().
 */
2319
int audit_set_loginuid(kuid_t loginuid)
L
Linus Torvalds 已提交
2320
{
2321
	struct task_struct *task = current;
2322
	struct audit_context *context = task->audit_context;
2323
	unsigned int sessionid;
2324

2325
#ifdef CONFIG_AUDIT_LOGINUID_IMMUTABLE
2326
	if (uid_valid(task->loginuid))
2327 2328 2329 2330 2331 2332 2333
		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
2334 2335 2336 2337 2338 2339
	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 "
2340 2341
				"old auid=%u new auid=%u"
				" old ses=%u new ses=%u",
2342 2343
				task->pid,
				from_kuid(&init_user_ns, task_uid(task)),
2344 2345
				from_kuid(&init_user_ns, task->loginuid),
				from_kuid(&init_user_ns, loginuid),
2346
				task->sessionid, sessionid);
A
Al Viro 已提交
2347
			audit_log_end(ab);
2348
		}
L
Linus Torvalds 已提交
2349
	}
2350
	task->sessionid = sessionid;
A
Al Viro 已提交
2351
	task->loginuid = loginuid;
L
Linus Torvalds 已提交
2352 2353 2354
	return 0;
}

2355 2356 2357 2358
/**
 * __audit_mq_open - record audit data for a POSIX MQ open
 * @oflag: open flag
 * @mode: mode bits
R
Randy Dunlap 已提交
2359
 * @attr: queue attributes
2360 2361
 *
 */
A
Al Viro 已提交
2362
void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
2363 2364 2365
{
	struct audit_context *context = current->audit_context;

A
Al Viro 已提交
2366 2367 2368 2369
	if (attr)
		memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
	else
		memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2370

A
Al Viro 已提交
2371 2372
	context->mq_open.oflag = oflag;
	context->mq_open.mode = mode;
2373

A
Al Viro 已提交
2374
	context->type = AUDIT_MQ_OPEN;
2375 2376 2377
}

/**
A
Al Viro 已提交
2378
 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2379 2380 2381
 * @mqdes: MQ descriptor
 * @msg_len: Message length
 * @msg_prio: Message priority
A
Al Viro 已提交
2382
 * @abs_timeout: Message timeout in absolute time
2383 2384
 *
 */
A
Al Viro 已提交
2385 2386
void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
			const struct timespec *abs_timeout)
2387 2388
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2389
	struct timespec *p = &context->mq_sendrecv.abs_timeout;
2390

A
Al Viro 已提交
2391 2392 2393 2394
	if (abs_timeout)
		memcpy(p, abs_timeout, sizeof(struct timespec));
	else
		memset(p, 0, sizeof(struct timespec));
2395

A
Al Viro 已提交
2396 2397 2398
	context->mq_sendrecv.mqdes = mqdes;
	context->mq_sendrecv.msg_len = msg_len;
	context->mq_sendrecv.msg_prio = msg_prio;
2399

A
Al Viro 已提交
2400
	context->type = AUDIT_MQ_SENDRECV;
2401 2402 2403 2404 2405
}

/**
 * __audit_mq_notify - record audit data for a POSIX MQ notify
 * @mqdes: MQ descriptor
R
Randy Dunlap 已提交
2406
 * @notification: Notification event
2407 2408 2409
 *
 */

A
Al Viro 已提交
2410
void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2411 2412 2413
{
	struct audit_context *context = current->audit_context;

A
Al Viro 已提交
2414 2415 2416 2417
	if (notification)
		context->mq_notify.sigev_signo = notification->sigev_signo;
	else
		context->mq_notify.sigev_signo = 0;
2418

A
Al Viro 已提交
2419 2420
	context->mq_notify.mqdes = mqdes;
	context->type = AUDIT_MQ_NOTIFY;
2421 2422 2423 2424 2425 2426 2427 2428
}

/**
 * __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
2429
void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2430 2431
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2432 2433 2434
	context->mq_getsetattr.mqdes = mqdes;
	context->mq_getsetattr.mqstat = *mqstat;
	context->type = AUDIT_MQ_GETSETATTR;
2435 2436
}

2437
/**
S
Steve Grubb 已提交
2438 2439 2440 2441
 * audit_ipc_obj - record audit data for ipc object
 * @ipcp: ipc permissions
 *
 */
A
Al Viro 已提交
2442
void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
S
Steve Grubb 已提交
2443 2444
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2445 2446 2447
	context->ipc.uid = ipcp->uid;
	context->ipc.gid = ipcp->gid;
	context->ipc.mode = ipcp->mode;
A
Al Viro 已提交
2448
	context->ipc.has_perm = 0;
A
Al Viro 已提交
2449 2450
	security_ipc_getsecid(ipcp, &context->ipc.osid);
	context->type = AUDIT_IPC;
S
Steve Grubb 已提交
2451 2452 2453 2454
}

/**
 * audit_ipc_set_perm - record audit data for new ipc permissions
2455 2456 2457 2458 2459
 * @qbytes: msgq bytes
 * @uid: msgq user id
 * @gid: msgq group id
 * @mode: msgq mode (permissions)
 *
A
Al Viro 已提交
2460
 * Called only after audit_ipc_obj().
2461
 */
A
Al Viro 已提交
2462
void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
L
Linus Torvalds 已提交
2463 2464 2465
{
	struct audit_context *context = current->audit_context;

A
Al Viro 已提交
2466 2467 2468 2469 2470
	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
2471
}
2472

2473
int __audit_bprm(struct linux_binprm *bprm)
A
Al Viro 已提交
2474 2475 2476 2477
{
	struct audit_aux_data_execve *ax;
	struct audit_context *context = current->audit_context;

P
Peter Zijlstra 已提交
2478
	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
A
Al Viro 已提交
2479 2480 2481 2482 2483
	if (!ax)
		return -ENOMEM;

	ax->argc = bprm->argc;
	ax->envc = bprm->envc;
P
Peter Zijlstra 已提交
2484
	ax->mm = bprm->mm;
A
Al Viro 已提交
2485 2486 2487 2488 2489 2490 2491
	ax->d.type = AUDIT_EXECVE;
	ax->d.next = context->aux;
	context->aux = (void *)ax;
	return 0;
}


2492 2493 2494 2495 2496 2497
/**
 * audit_socketcall - record audit data for sys_socketcall
 * @nargs: number of args
 * @args: args array
 *
 */
2498
void __audit_socketcall(int nargs, unsigned long *args)
2499 2500 2501
{
	struct audit_context *context = current->audit_context;

A
Al Viro 已提交
2502 2503 2504
	context->type = AUDIT_SOCKETCALL;
	context->socketcall.nargs = nargs;
	memcpy(context->socketcall.args, args, nargs * sizeof(unsigned long));
2505 2506
}

A
Al Viro 已提交
2507 2508 2509 2510 2511 2512
/**
 * __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
2513
void __audit_fd_pair(int fd1, int fd2)
A
Al Viro 已提交
2514 2515
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2516 2517
	context->fds[0] = fd1;
	context->fds[1] = fd2;
A
Al Viro 已提交
2518 2519
}

2520 2521 2522 2523 2524 2525 2526
/**
 * 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.
 */
2527
int __audit_sockaddr(int len, void *a)
2528 2529 2530
{
	struct audit_context *context = current->audit_context;

2531 2532 2533 2534 2535 2536
	if (!context->sockaddr) {
		void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
		if (!p)
			return -ENOMEM;
		context->sockaddr = p;
	}
2537

2538 2539
	context->sockaddr_len = len;
	memcpy(context->sockaddr, a, len);
2540 2541 2542
	return 0;
}

A
Al Viro 已提交
2543 2544 2545 2546 2547
void __audit_ptrace(struct task_struct *t)
{
	struct audit_context *context = current->audit_context;

	context->target_pid = t->pid;
2548
	context->target_auid = audit_get_loginuid(t);
2549
	context->target_uid = task_uid(t);
2550
	context->target_sessionid = audit_get_sessionid(t);
2551
	security_task_getsecid(t, &context->target_sid);
2552
	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
A
Al Viro 已提交
2553 2554
}

2555 2556 2557 2558 2559 2560 2561 2562
/**
 * 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
2563
int __audit_signal_info(int sig, struct task_struct *t)
2564
{
A
Amy Griffis 已提交
2565 2566 2567
	struct audit_aux_data_pids *axp;
	struct task_struct *tsk = current;
	struct audit_context *ctx = tsk->audit_context;
2568
	kuid_t uid = current_uid(), t_uid = task_uid(t);
2569

A
Al Viro 已提交
2570
	if (audit_pid && t->tgid == audit_pid) {
2571
		if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
A
Al Viro 已提交
2572
			audit_sig_pid = tsk->pid;
2573
			if (uid_valid(tsk->loginuid))
A
Al Viro 已提交
2574
				audit_sig_uid = tsk->loginuid;
A
Al Viro 已提交
2575
			else
2576
				audit_sig_uid = uid;
2577
			security_task_getsecid(tsk, &audit_sig_sid);
A
Al Viro 已提交
2578 2579 2580
		}
		if (!audit_signals || audit_dummy_context())
			return 0;
2581
	}
A
Amy Griffis 已提交
2582 2583 2584 2585 2586

	/* optimize the common case by putting first signal recipient directly
	 * in audit_context */
	if (!ctx->target_pid) {
		ctx->target_pid = t->tgid;
2587
		ctx->target_auid = audit_get_loginuid(t);
2588
		ctx->target_uid = t_uid;
2589
		ctx->target_sessionid = audit_get_sessionid(t);
2590
		security_task_getsecid(t, &ctx->target_sid);
2591
		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
A
Amy Griffis 已提交
2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604
		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;
	}
2605
	BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
A
Amy Griffis 已提交
2606 2607

	axp->target_pid[axp->pid_count] = t->tgid;
2608
	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2609
	axp->target_uid[axp->pid_count] = t_uid;
2610
	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2611
	security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2612
	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
A
Amy Griffis 已提交
2613 2614 2615
	axp->pid_count++;

	return 0;
2616
}
S
Steve Grubb 已提交
2617

2618 2619
/**
 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
D
David Howells 已提交
2620 2621 2622
 * @bprm: pointer to the bprm being processed
 * @new: the proposed new credentials
 * @old: the old credentials
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 *
 * 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
 */
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int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
			   const struct cred *new, const struct cred *old)
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{
	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)
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		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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}

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/**
 * __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)
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{
	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;
}

2692
static void audit_log_task(struct audit_buffer *ab)
2693
{
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	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);
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}

static void audit_log_abend(struct audit_buffer *ab, char *reason, long signr)
{
	audit_log_task(ab);
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	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
2721
 * @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);
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	if (unlikely(!ab))
		return;
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	audit_log_abend(ab, "memory violation", signr);
	audit_log_end(ab);
}
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2743
void __audit_seccomp(unsigned long syscall, long signr, int code)
2744 2745 2746
{
	struct audit_buffer *ab;

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	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_SECCOMP);
	if (unlikely(!ab))
		return;
	audit_log_task(ab);
	audit_log_format(ab, " sig=%ld", signr);
2752
	audit_log_format(ab, " syscall=%ld", syscall);
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	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;
}