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;
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			long args[AUDITSC_ARGS];
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		} 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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Linus Torvalds 已提交
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
Linus Torvalds 已提交
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
Linus Torvalds 已提交
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
Linus Torvalds 已提交
612
		case AUDIT_PID:
613
			result = audit_comparator(tsk->pid, f->op, f->val);
L
Linus Torvalds 已提交
614
			break;
A
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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
			}
A
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621
			break;
L
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622
		case AUDIT_UID:
623
			result = audit_uid_comparator(cred->uid, f->op, f->uid);
L
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624 625
			break;
		case AUDIT_EUID:
626
			result = audit_uid_comparator(cred->euid, f->op, f->uid);
L
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627 628
			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);
L
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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);
			}
L
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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
			}
L
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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;
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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);
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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 */
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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
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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
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	}

	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 1005
		int i = 0;

1006
		printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d"
L
Linus Torvalds 已提交
1007 1008
		       " name_count=%d put_count=%d"
		       " ino_count=%d [NOT freeing]\n",
1009
		       __FILE__, __LINE__,
L
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1010 1011 1012
		       context->serial, context->major, context->in_syscall,
		       context->name_count, context->put_count,
		       context->ino_count);
1013
		list_for_each_entry(n, &context->names_list, list) {
1014
			printk(KERN_ERR "names[%d] = %p = %s\n", i++,
1015
			       n->name, n->name->name ?: "(null)");
1016
		}
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1017 1018 1019 1020 1021 1022 1023 1024 1025
		dump_stack();
		return;
	}
#endif
#if AUDIT_DEBUG
	context->put_count  = 0;
	context->ino_count  = 0;
#endif

1026 1027 1028
	list_for_each_entry_safe(n, next, &context->names_list, list) {
		list_del(&n->list);
		if (n->name && n->name_put)
1029
			final_putname(n->name);
1030 1031
		if (n->should_free)
			kfree(n);
1032
	}
L
Linus Torvalds 已提交
1033
	context->name_count = 0;
1034 1035 1036
	path_put(&context->pwd);
	context->pwd.dentry = NULL;
	context->pwd.mnt = NULL;
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}

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

	while ((aux = context->aux)) {
		context->aux = aux->next;
		kfree(aux);
	}
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Amy Griffis 已提交
1047 1048 1049 1050
	while ((aux = context->aux_pids)) {
		context->aux_pids = aux->next;
		kfree(aux);
	}
L
Linus Torvalds 已提交
1051 1052 1053 1054 1055 1056
}

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

1057 1058
	context = kzalloc(sizeof(*context), GFP_KERNEL);
	if (!context)
L
Linus Torvalds 已提交
1059
		return NULL;
1060 1061
	context->state = state;
	context->prio = state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
A
Al Viro 已提交
1062
	INIT_LIST_HEAD(&context->killed_trees);
1063
	INIT_LIST_HEAD(&context->names_list);
L
Linus Torvalds 已提交
1064 1065 1066
	return context;
}

1067 1068 1069 1070 1071
/**
 * 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
1072 1073
 * if necessary.  Doing so turns on system call auditing for the
 * specified task.  This is called from copy_process, so no lock is
1074 1075
 * needed.
 */
L
Linus Torvalds 已提交
1076 1077 1078 1079
int audit_alloc(struct task_struct *tsk)
{
	struct audit_context *context;
	enum audit_state     state;
1080
	char *key = NULL;
L
Linus Torvalds 已提交
1081

1082
	if (likely(!audit_ever_enabled))
L
Linus Torvalds 已提交
1083 1084
		return 0; /* Return if not auditing. */

1085
	state = audit_filter_task(tsk, &key);
1086
	if (state == AUDIT_DISABLED)
L
Linus Torvalds 已提交
1087 1088 1089
		return 0;

	if (!(context = audit_alloc_context(state))) {
1090
		kfree(key);
L
Linus Torvalds 已提交
1091 1092 1093
		audit_log_lost("out of memory in audit_alloc");
		return -ENOMEM;
	}
1094
	context->filterkey = key;
L
Linus Torvalds 已提交
1095 1096 1097 1098 1099 1100 1101 1102

	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
1103 1104 1105 1106 1107 1108 1109
	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
1110 1111
}

1112
int audit_log_task_context(struct audit_buffer *ab)
1113 1114
{
	char *ctx = NULL;
1115 1116 1117 1118
	unsigned len;
	int error;
	u32 sid;

1119
	security_task_getsecid(current, &sid);
1120
	if (!sid)
1121
		return 0;
1122

1123
	error = security_secid_to_secctx(sid, &ctx, &len);
1124 1125
	if (error) {
		if (error != -EINVAL)
1126
			goto error_path;
1127
		return 0;
1128 1129 1130
	}

	audit_log_format(ab, " subj=%s", ctx);
1131
	security_release_secctx(ctx, len);
1132
	return 0;
1133 1134

error_path:
1135
	audit_panic("error in audit_log_task_context");
1136
	return error;
1137 1138
}

J
Joy Latten 已提交
1139 1140
EXPORT_SYMBOL(audit_log_task_context);

P
Peter Moody 已提交
1141
void audit_log_task_info(struct audit_buffer *ab, struct task_struct *tsk)
1142
{
P
Peter Moody 已提交
1143
	const struct cred *cred;
1144 1145
	char name[sizeof(tsk->comm)];
	struct mm_struct *mm = tsk->mm;
P
Peter Moody 已提交
1146 1147 1148 1149
	char *tty;

	if (!ab)
		return;
1150

1151
	/* tsk == current */
P
Peter Moody 已提交
1152 1153 1154
	cred = current_cred();

	spin_lock_irq(&tsk->sighand->siglock);
A
Alan Cox 已提交
1155
	if (tsk->signal && tsk->signal->tty)
P
Peter Moody 已提交
1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167
		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,
1168 1169 1170 1171 1172 1173 1174 1175 1176
			 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
1177
			 tsk->sessionid, tty);
1178

1179
	get_task_comm(name, tsk);
1180 1181
	audit_log_format(ab, " comm=");
	audit_log_untrustedstring(ab, name);
1182

1183 1184
	if (mm) {
		down_read(&mm->mmap_sem);
1185 1186
		if (mm->exe_file)
			audit_log_d_path(ab, " exe=", &mm->exe_file->f_path);
1187
		up_read(&mm->mmap_sem);
1188
	}
1189
	audit_log_task_context(ab);
1190 1191
}

P
Peter Moody 已提交
1192 1193
EXPORT_SYMBOL(audit_log_task_info);

A
Amy Griffis 已提交
1194
static int audit_log_pid_context(struct audit_context *context, pid_t pid,
1195
				 kuid_t auid, kuid_t uid, unsigned int sessionid,
1196
				 u32 sid, char *comm)
A
Amy Griffis 已提交
1197 1198
{
	struct audit_buffer *ab;
1199
	char *ctx = NULL;
A
Amy Griffis 已提交
1200 1201 1202 1203 1204
	u32 len;
	int rc = 0;

	ab = audit_log_start(context, GFP_KERNEL, AUDIT_OBJ_PID);
	if (!ab)
1205
		return rc;
A
Amy Griffis 已提交
1206

1207 1208
	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
			 from_kuid(&init_user_ns, auid),
1209
			 from_kuid(&init_user_ns, uid), sessionid);
1210 1211 1212 1213 1214 1215 1216 1217
	if (sid) {
		if (security_secid_to_secctx(sid, &ctx, &len)) {
			audit_log_format(ab, " obj=(none)");
			rc = 1;
		} else {
			audit_log_format(ab, " obj=%s", ctx);
			security_release_secctx(ctx, len);
		}
1218
	}
1219 1220
	audit_log_format(ab, " ocomm=");
	audit_log_untrustedstring(ab, comm);
A
Amy Griffis 已提交
1221 1222 1223 1224 1225
	audit_log_end(ab);

	return rc;
}

1226 1227 1228
/*
 * 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
1229
 * within about 500 bytes (next page boundary)
1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242
 *
 * 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
1243
{
1244 1245
	char arg_num_len_buf[12];
	const char __user *tmp_p = p;
1246 1247
	/* 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;
1248 1249 1250 1251 1252 1253 1254
	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
1255

1256 1257 1258 1259 1260 1261
	/*
	 * 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.
	 */
1262
	if (unlikely((len == -1) || len > MAX_ARG_STRLEN - 1)) {
1263 1264
		WARN_ON(1);
		send_sig(SIGKILL, current, 0);
1265
		return -1;
1266
	}
1267

1268 1269 1270 1271 1272 1273 1274
	/* 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
1275
		/*
1276 1277 1278
		 * 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
1279
		 */
1280
		if (ret) {
P
Peter Zijlstra 已提交
1281 1282
			WARN_ON(1);
			send_sig(SIGKILL, current, 0);
1283
			return -1;
P
Peter Zijlstra 已提交
1284
		}
1285 1286 1287 1288 1289 1290 1291 1292
		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
1293 1294
			break;
		}
1295 1296 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
		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
1326 1327

		/*
1328 1329 1330 1331
		 * first record needs to say how long the original string was
		 * so we can be sure nothing was lost.
		 */
		if ((i == 0) && (too_long))
1332
			audit_log_format(*ab, " a%d_len=%zu", arg_num,
1333 1334 1335 1336 1337 1338
					 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
1339
		 */
1340 1341 1342 1343
		if (len >= max_execve_audit_len)
			ret = copy_from_user(buf, p, to_send);
		else
			ret = 0;
1344
		if (ret) {
P
Peter Zijlstra 已提交
1345 1346
			WARN_ON(1);
			send_sig(SIGKILL, current, 0);
1347
			return -1;
P
Peter Zijlstra 已提交
1348
		}
1349 1350 1351
		buf[to_send] = '\0';

		/* actually log it */
1352
		audit_log_format(*ab, " a%d", arg_num);
1353 1354 1355 1356
		if (too_long)
			audit_log_format(*ab, "[%d]", i);
		audit_log_format(*ab, "=");
		if (has_cntl)
1357
			audit_log_n_hex(*ab, buf, to_send);
1358
		else
1359
			audit_log_string(*ab, buf);
1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376

		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)
{
1377 1378
	int i, len;
	size_t len_sent = 0;
1379 1380
	const char __user *p;
	char *buf;
P
Peter Zijlstra 已提交
1381

1382 1383 1384 1385
	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
1386

1387
	audit_log_format(*ab, "argc=%d", axi->argc);
1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398

	/*
	 * 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
1399
	}
1400 1401 1402 1403 1404 1405 1406 1407 1408

	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
1409 1410
}

1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439
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
1440
static void show_special(struct audit_context *context, int *call_panic)
A
Al Viro 已提交
1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456
{
	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
1457 1458 1459
	case AUDIT_IPC: {
		u32 osid = context->ipc.osid;

A
Al Viro 已提交
1460
		audit_log_format(ab, "ouid=%u ogid=%u mode=%#ho",
1461 1462 1463
				 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
1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474
		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
1475 1476 1477 1478
		if (context->ipc.has_perm) {
			audit_log_end(ab);
			ab = audit_log_start(context, GFP_KERNEL,
					     AUDIT_IPC_SET_PERM);
1479 1480
			if (unlikely(!ab))
				return;
A
Al Viro 已提交
1481
			audit_log_format(ab,
A
Al Viro 已提交
1482
				"qbytes=%lx ouid=%u ogid=%u mode=%#ho",
A
Al Viro 已提交
1483 1484 1485 1486 1487
				context->ipc.qbytes,
				context->ipc.perm_uid,
				context->ipc.perm_gid,
				context->ipc.perm_mode);
		}
A
Al Viro 已提交
1488
		break; }
A
Al Viro 已提交
1489 1490
	case AUDIT_MQ_OPEN: {
		audit_log_format(ab,
A
Al Viro 已提交
1491
			"oflag=0x%x mode=%#ho mq_flags=0x%lx mq_maxmsg=%ld "
A
Al Viro 已提交
1492 1493 1494 1495 1496 1497 1498
			"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
1499 1500 1501 1502 1503 1504 1505 1506 1507 1508
	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
1509 1510 1511 1512 1513
	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
1514 1515 1516 1517 1518 1519 1520 1521 1522
	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
1523 1524 1525 1526 1527 1528
	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
1529 1530 1531 1532
	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
1533 1534 1535 1536
	}
	audit_log_end(ab);
}

1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551
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=");
1552
			audit_log_untrustedstring(ab, n->name->name);
1553 1554 1555 1556
			break;
		case 0:
			/* name was specified as a relative path and the
			 * directory component is the cwd */
1557
			audit_log_d_path(ab, " name=", &context->pwd);
1558 1559 1560 1561
			break;
		default:
			/* log the name's directory component */
			audit_log_format(ab, " name=");
1562
			audit_log_n_untrustedstring(ab, n->name->name,
1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575
						    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,
1576 1577
				 from_kuid(&init_user_ns, n->uid),
				 from_kgid(&init_user_ns, n->gid),
1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598
				 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);
}

1599
static void audit_log_exit(struct audit_context *context, struct task_struct *tsk)
L
Linus Torvalds 已提交
1600
{
S
Steve Grubb 已提交
1601
	int i, call_panic = 0;
L
Linus Torvalds 已提交
1602
	struct audit_buffer *ab;
1603
	struct audit_aux_data *aux;
1604
	struct audit_names *n;
L
Linus Torvalds 已提交
1605

1606
	/* tsk == current */
1607
	context->personality = tsk->personality;
1608 1609

	ab = audit_log_start(context, GFP_KERNEL, AUDIT_SYSCALL);
L
Linus Torvalds 已提交
1610 1611
	if (!ab)
		return;		/* audit_panic has been called */
1612 1613
	audit_log_format(ab, "arch=%x syscall=%d",
			 context->arch, context->major);
L
Linus Torvalds 已提交
1614 1615 1616
	if (context->personality != PER_LINUX)
		audit_log_format(ab, " per=%lx", context->personality);
	if (context->return_valid)
D
Daniel Walker 已提交
1617
		audit_log_format(ab, " success=%s exit=%ld",
1618 1619
				 (context->return_valid==AUDITSC_SUCCESS)?"yes":"no",
				 context->return_code);
A
Alan Cox 已提交
1620

L
Linus Torvalds 已提交
1621
	audit_log_format(ab,
P
Peter Moody 已提交
1622 1623 1624 1625 1626 1627
			 " 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
1628

1629
	audit_log_task_info(ab, tsk);
1630
	audit_log_key(ab, context->filterkey);
L
Linus Torvalds 已提交
1631 1632
	audit_log_end(ab);

1633
	for (aux = context->aux; aux; aux = aux->next) {
1634

1635
		ab = audit_log_start(context, GFP_KERNEL, aux->type);
L
Linus Torvalds 已提交
1636 1637 1638 1639
		if (!ab)
			continue; /* audit_panic has been called */

		switch (aux->type) {
1640

A
Al Viro 已提交
1641 1642
		case AUDIT_EXECVE: {
			struct audit_aux_data_execve *axi = (void *)aux;
1643
			audit_log_execve_info(context, &ab, axi);
A
Al Viro 已提交
1644
			break; }
S
Steve Grubb 已提交
1645

1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659
		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
1660 1661 1662 1663
		}
		audit_log_end(ab);
	}

A
Al Viro 已提交
1664
	if (context->type)
A
Al Viro 已提交
1665
		show_special(context, &call_panic);
A
Al Viro 已提交
1666

A
Al Viro 已提交
1667 1668 1669 1670 1671 1672 1673 1674 1675
	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);
		}
	}

1676 1677 1678 1679 1680 1681 1682 1683 1684 1685
	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
1686 1687 1688 1689 1690
	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],
1691 1692
						  axs->target_auid[i],
						  axs->target_uid[i],
1693
						  axs->target_sessionid[i],
1694 1695
						  axs->target_sid[i],
						  axs->target_comm[i]))
A
Amy Griffis 已提交
1696
				call_panic = 1;
A
Al Viro 已提交
1697 1698
	}

A
Amy Griffis 已提交
1699 1700
	if (context->target_pid &&
	    audit_log_pid_context(context, context->target_pid,
1701
				  context->target_auid, context->target_uid,
1702
				  context->target_sessionid,
1703
				  context->target_sid, context->target_comm))
A
Amy Griffis 已提交
1704 1705
			call_panic = 1;

1706
	if (context->pwd.dentry && context->pwd.mnt) {
1707
		ab = audit_log_start(context, GFP_KERNEL, AUDIT_CWD);
1708
		if (ab) {
1709
			audit_log_d_path(ab, " cwd=", &context->pwd);
1710 1711 1712
			audit_log_end(ab);
		}
	}
1713

1714 1715 1716
	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
1717 1718 1719 1720 1721

	/* 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
1722 1723
	if (call_panic)
		audit_panic("error converting sid to string");
L
Linus Torvalds 已提交
1724 1725
}

1726 1727 1728 1729
/**
 * audit_free - free a per-task audit context
 * @tsk: task whose audit context block to free
 *
1730
 * Called from copy_process and do_exit
1731
 */
1732
void __audit_free(struct task_struct *tsk)
L
Linus Torvalds 已提交
1733 1734 1735 1736
{
	struct audit_context *context;

	context = audit_get_context(tsk, 0, 0);
1737
	if (!context)
L
Linus Torvalds 已提交
1738 1739 1740
		return;

	/* Check for system calls that do not go through the exit
D
Daniel Walker 已提交
1741 1742
	 * function (e.g., exit_group), then free context block.
	 * We use GFP_ATOMIC here because we might be doing this
1743
	 * in the context of the idle thread */
1744
	/* that can happen only if we are called from do_exit() */
1745
	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1746
		audit_log_exit(context, tsk);
A
Al Viro 已提交
1747 1748
	if (!list_empty(&context->killed_trees))
		audit_kill_trees(&context->killed_trees);
L
Linus Torvalds 已提交
1749 1750 1751 1752

	audit_free_context(context);
}

1753 1754 1755 1756 1757 1758 1759 1760 1761 1762
/**
 * 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
1763 1764 1765 1766 1767
 * 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
1768 1769
 * be written).
 */
1770
void __audit_syscall_entry(int arch, int major,
L
Linus Torvalds 已提交
1771 1772 1773
			 unsigned long a1, unsigned long a2,
			 unsigned long a3, unsigned long a4)
{
1774
	struct task_struct *tsk = current;
L
Linus Torvalds 已提交
1775 1776 1777
	struct audit_context *context = tsk->audit_context;
	enum audit_state     state;

1778
	if (!context)
R
Roland McGrath 已提交
1779
		return;
L
Linus Torvalds 已提交
1780 1781 1782 1783 1784 1785

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

	if (!audit_enabled)
		return;

1786
	context->arch	    = arch;
L
Linus Torvalds 已提交
1787 1788 1789 1790 1791 1792 1793
	context->major      = major;
	context->argv[0]    = a1;
	context->argv[1]    = a2;
	context->argv[2]    = a3;
	context->argv[3]    = a4;

	state = context->state;
1794
	context->dummy = !audit_n_rules;
1795 1796
	if (!context->dummy && state == AUDIT_BUILD_CONTEXT) {
		context->prio = 0;
1797
		state = audit_filter_syscall(tsk, context, &audit_filter_list[AUDIT_FILTER_ENTRY]);
1798
	}
1799
	if (state == AUDIT_DISABLED)
L
Linus Torvalds 已提交
1800 1801
		return;

1802
	context->serial     = 0;
L
Linus Torvalds 已提交
1803 1804
	context->ctime      = CURRENT_TIME;
	context->in_syscall = 1;
1805
	context->current_state  = state;
A
Alexander Viro 已提交
1806
	context->ppid       = 0;
L
Linus Torvalds 已提交
1807 1808
}

1809 1810
/**
 * audit_syscall_exit - deallocate audit context after a system call
1811 1812
 * @success: success value of the syscall
 * @return_code: return value of the syscall
1813 1814
 *
 * Tear down after system call.  If the audit context has been marked as
L
Linus Torvalds 已提交
1815
 * auditable (either because of the AUDIT_RECORD_CONTEXT state from
1816
 * filtering, or because some other part of the kernel wrote an audit
L
Linus Torvalds 已提交
1817
 * message), then write out the syscall information.  In call cases,
1818 1819
 * free the names stored from getname().
 */
1820
void __audit_syscall_exit(int success, long return_code)
L
Linus Torvalds 已提交
1821
{
1822
	struct task_struct *tsk = current;
L
Linus Torvalds 已提交
1823 1824
	struct audit_context *context;

1825 1826 1827 1828
	if (success)
		success = AUDITSC_SUCCESS;
	else
		success = AUDITSC_FAILURE;
L
Linus Torvalds 已提交
1829

1830
	context = audit_get_context(tsk, success, return_code);
1831
	if (!context)
1832
		return;
L
Linus Torvalds 已提交
1833

1834
	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
1835
		audit_log_exit(context, tsk);
L
Linus Torvalds 已提交
1836 1837

	context->in_syscall = 0;
1838
	context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
1839

A
Al Viro 已提交
1840 1841 1842
	if (!list_empty(&context->killed_trees))
		audit_kill_trees(&context->killed_trees);

A
Al Viro 已提交
1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855
	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
1856
	}
A
Al Viro 已提交
1857
	tsk->audit_context = context;
L
Linus Torvalds 已提交
1858 1859
}

A
Al Viro 已提交
1860 1861 1862 1863 1864 1865 1866
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;
1867
	if (likely(hlist_empty(&inode->i_fsnotify_marks)))
A
Al Viro 已提交
1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879
		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
1880
		printk(KERN_WARNING "out of memory, audit has lost a tree reference\n");
A
Al Viro 已提交
1881 1882 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
		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;
1910
		if (inode && unlikely(!hlist_empty(&inode->i_fsnotify_marks))) {
A
Al Viro 已提交
1911 1912 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
			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
1940
			"out of memory, audit has lost a tree reference\n");
A
Al Viro 已提交
1941 1942 1943 1944 1945 1946 1947 1948
		unroll_tree_refs(context, p, count);
		audit_set_auditable(context);
		return;
	}
	rcu_read_unlock();
#endif
}

1949 1950
static struct audit_names *audit_alloc_name(struct audit_context *context,
						unsigned char type)
1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964
{
	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;
1965
	aname->type = type;
1966 1967 1968 1969 1970 1971 1972 1973 1974
	list_add_tail(&aname->list, &context->names_list);

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

1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997
/**
 * 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;
}

1998 1999 2000 2001 2002 2003 2004
/**
 * 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().
 */
2005
void __audit_getname(struct filename *name)
L
Linus Torvalds 已提交
2006 2007
{
	struct audit_context *context = current->audit_context;
2008
	struct audit_names *n;
L
Linus Torvalds 已提交
2009 2010 2011 2012 2013 2014 2015 2016 2017

	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;
	}
2018

2019 2020 2021 2022 2023
#if AUDIT_DEBUG
	/* The filename _must_ have a populated ->name */
	BUG_ON(!name->name);
#endif

2024
	n = audit_alloc_name(context, AUDIT_TYPE_UNKNOWN);
2025 2026 2027 2028 2029 2030
	if (!n)
		return;

	n->name = name;
	n->name_len = AUDIT_NAME_FULL;
	n->name_put = true;
2031
	name->aname = n;
2032

2033 2034
	if (!context->pwd.dentry)
		get_fs_pwd(current->fs, &context->pwd);
L
Linus Torvalds 已提交
2035 2036
}

2037 2038 2039 2040 2041 2042 2043
/* 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().
 */
2044
void audit_putname(struct filename *name)
L
Linus Torvalds 已提交
2045 2046 2047 2048 2049 2050
{
	struct audit_context *context = current->audit_context;

	BUG_ON(!context);
	if (!context->in_syscall) {
#if AUDIT_DEBUG == 2
2051
		printk(KERN_ERR "%s:%d(:%d): final_putname(%p)\n",
L
Linus Torvalds 已提交
2052 2053
		       __FILE__, __LINE__, context->serial, name);
		if (context->name_count) {
2054
			struct audit_names *n;
2055
			int i = 0;
2056 2057

			list_for_each_entry(n, &context->names_list, list)
2058
				printk(KERN_ERR "name[%d] = %p = %s\n", i++,
2059
				       n->name, n->name->name ?: "(null)");
2060
			}
L
Linus Torvalds 已提交
2061
#endif
2062
		final_putname(name);
L
Linus Torvalds 已提交
2063 2064 2065 2066 2067 2068 2069 2070 2071 2072
	}
#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,
2073 2074
			       context->in_syscall, name->name,
			       context->name_count, context->put_count);
L
Linus Torvalds 已提交
2075 2076 2077 2078 2079 2080
			dump_stack();
		}
	}
#endif
}

2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101
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;
}


2102
/* Copy inode data into an audit_names. */
2103 2104
static void audit_copy_inode(struct audit_names *name, const struct dentry *dentry,
			     const struct inode *inode)
2105
{
2106 2107 2108 2109 2110 2111
	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;
2112
	security_inode_getsecid(inode, &name->osid);
2113
	audit_copy_fcaps(name, dentry);
2114 2115
}

2116
/**
2117
 * __audit_inode - store the inode and device from a lookup
2118
 * @name: name being audited
2119
 * @dentry: dentry being audited
2120
 * @parent: does this dentry represent the parent?
2121
 */
2122
void __audit_inode(struct filename *name, const struct dentry *dentry,
2123
		   unsigned int parent)
L
Linus Torvalds 已提交
2124 2125
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2126
	const struct inode *inode = dentry->d_inode;
2127
	struct audit_names *n;
L
Linus Torvalds 已提交
2128 2129 2130

	if (!context->in_syscall)
		return;
2131

2132 2133 2134
	if (!name)
		goto out_alloc;

2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154
#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;
		}
	}

2155
	list_for_each_entry_reverse(n, &context->names_list, list) {
2156
		/* does the name pointer match? */
2157
		if (!n->name || n->name->name != name->name)
2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168
			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
2169
	}
2170

2171
out_alloc:
2172 2173 2174
	/* unable to find the name from a previous getname(). Allocate a new
	 * anonymous entry.
	 */
2175
	n = audit_alloc_name(context, AUDIT_TYPE_NORMAL);
2176 2177 2178
	if (!n)
		return;
out:
2179
	if (parent) {
2180
		n->name_len = n->name ? parent_len(n->name->name) : AUDIT_NAME_FULL;
2181 2182 2183 2184 2185
		n->type = AUDIT_TYPE_PARENT;
	} else {
		n->name_len = AUDIT_NAME_FULL;
		n->type = AUDIT_TYPE_NORMAL;
	}
A
Al Viro 已提交
2186
	handle_path(dentry);
2187
	audit_copy_inode(n, dentry, inode);
2188 2189 2190
}

/**
2191
 * __audit_inode_child - collect inode info for created/removed objects
2192
 * @parent: inode of dentry parent
2193
 * @dentry: dentry being audited
2194
 * @type:   AUDIT_TYPE_* value that we're looking for
2195 2196 2197 2198 2199 2200 2201 2202 2203
 *
 * 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.
 */
2204
void __audit_inode_child(const struct inode *parent,
2205 2206
			 const struct dentry *dentry,
			 const unsigned char type)
2207 2208
{
	struct audit_context *context = current->audit_context;
2209
	const struct inode *inode = dentry->d_inode;
2210
	const char *dname = dentry->d_name.name;
2211
	struct audit_names *n, *found_parent = NULL, *found_child = NULL;
2212 2213 2214 2215

	if (!context->in_syscall)
		return;

A
Al Viro 已提交
2216 2217
	if (inode)
		handle_one(inode);
2218

2219
	/* look for a parent entry first */
2220
	list_for_each_entry(n, &context->names_list, list) {
2221
		if (!n->name || n->type != AUDIT_TYPE_PARENT)
A
Amy Griffis 已提交
2222 2223 2224
			continue;

		if (n->ino == parent->i_ino &&
2225
		    !audit_compare_dname_path(dname, n->name->name, n->name_len)) {
2226 2227
			found_parent = n;
			break;
A
Amy Griffis 已提交
2228
		}
A
Amy Griffis 已提交
2229
	}
2230

2231
	/* is there a matching child entry? */
2232
	list_for_each_entry(n, &context->names_list, list) {
2233 2234 2235 2236 2237 2238
		/* 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
2239 2240
			continue;

2241 2242
		if (!strcmp(dname, n->name->name) ||
		    !audit_compare_dname_path(dname, n->name->name,
2243 2244
						found_parent ?
						found_parent->name_len :
2245
						AUDIT_NAME_FULL)) {
2246 2247
			found_child = n;
			break;
A
Amy Griffis 已提交
2248
		}
S
Steve Grubb 已提交
2249
	}
A
Amy Griffis 已提交
2250 2251

	if (!found_parent) {
2252 2253
		/* create a new, "anonymous" parent record */
		n = audit_alloc_name(context, AUDIT_TYPE_PARENT);
2254
		if (!n)
S
Steve Grubb 已提交
2255
			return;
2256
		audit_copy_inode(n, NULL, parent);
2257
	}
A
Amy Griffis 已提交
2258 2259

	if (!found_child) {
2260 2261
		found_child = audit_alloc_name(context, type);
		if (!found_child)
A
Amy Griffis 已提交
2262 2263 2264 2265 2266 2267
			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) {
2268 2269
			found_child->name = found_parent->name;
			found_child->name_len = AUDIT_NAME_FULL;
A
Amy Griffis 已提交
2270
			/* don't call __putname() */
2271
			found_child->name_put = false;
A
Amy Griffis 已提交
2272 2273
		}
	}
2274 2275 2276 2277
	if (inode)
		audit_copy_inode(found_child, dentry, inode);
	else
		found_child->ino = (unsigned long)-1;
2278
}
2279
EXPORT_SYMBOL_GPL(__audit_inode_child);
2280

2281 2282 2283 2284 2285 2286 2287 2288
/**
 * 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.
 */
2289
int auditsc_get_stamp(struct audit_context *ctx,
2290
		       struct timespec *t, unsigned int *serial)
L
Linus Torvalds 已提交
2291
{
2292 2293
	if (!ctx->in_syscall)
		return 0;
2294 2295
	if (!ctx->serial)
		ctx->serial = audit_serial();
2296 2297 2298
	t->tv_sec  = ctx->ctime.tv_sec;
	t->tv_nsec = ctx->ctime.tv_nsec;
	*serial    = ctx->serial;
2299 2300 2301 2302
	if (!ctx->prio) {
		ctx->prio = 1;
		ctx->current_state = AUDIT_RECORD_CONTEXT;
	}
2303
	return 1;
L
Linus Torvalds 已提交
2304 2305
}

2306 2307 2308
/* global counter which is incremented every time something logs in */
static atomic_t session_id = ATOMIC_INIT(0);

2309
/**
2310
 * audit_set_loginuid - set current task's audit_context loginuid
2311 2312 2313 2314 2315 2316
 * @loginuid: loginuid value
 *
 * Returns 0.
 *
 * Called (set) from fs/proc/base.c::proc_loginuid_write().
 */
2317
int audit_set_loginuid(kuid_t loginuid)
L
Linus Torvalds 已提交
2318
{
2319
	struct task_struct *task = current;
2320
	struct audit_context *context = task->audit_context;
2321
	unsigned int sessionid;
2322

2323
#ifdef CONFIG_AUDIT_LOGINUID_IMMUTABLE
2324
	if (uid_valid(task->loginuid))
2325 2326 2327 2328 2329 2330 2331
		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
2332 2333 2334 2335 2336 2337
	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 "
2338 2339
				"old auid=%u new auid=%u"
				" old ses=%u new ses=%u",
2340 2341
				task->pid,
				from_kuid(&init_user_ns, task_uid(task)),
2342 2343
				from_kuid(&init_user_ns, task->loginuid),
				from_kuid(&init_user_ns, loginuid),
2344
				task->sessionid, sessionid);
A
Al Viro 已提交
2345
			audit_log_end(ab);
2346
		}
L
Linus Torvalds 已提交
2347
	}
2348
	task->sessionid = sessionid;
A
Al Viro 已提交
2349
	task->loginuid = loginuid;
L
Linus Torvalds 已提交
2350 2351 2352
	return 0;
}

2353 2354 2355 2356
/**
 * __audit_mq_open - record audit data for a POSIX MQ open
 * @oflag: open flag
 * @mode: mode bits
R
Randy Dunlap 已提交
2357
 * @attr: queue attributes
2358 2359
 *
 */
A
Al Viro 已提交
2360
void __audit_mq_open(int oflag, umode_t mode, struct mq_attr *attr)
2361 2362 2363
{
	struct audit_context *context = current->audit_context;

A
Al Viro 已提交
2364 2365 2366 2367
	if (attr)
		memcpy(&context->mq_open.attr, attr, sizeof(struct mq_attr));
	else
		memset(&context->mq_open.attr, 0, sizeof(struct mq_attr));
2368

A
Al Viro 已提交
2369 2370
	context->mq_open.oflag = oflag;
	context->mq_open.mode = mode;
2371

A
Al Viro 已提交
2372
	context->type = AUDIT_MQ_OPEN;
2373 2374 2375
}

/**
A
Al Viro 已提交
2376
 * __audit_mq_sendrecv - record audit data for a POSIX MQ timed send/receive
2377 2378 2379
 * @mqdes: MQ descriptor
 * @msg_len: Message length
 * @msg_prio: Message priority
A
Al Viro 已提交
2380
 * @abs_timeout: Message timeout in absolute time
2381 2382
 *
 */
A
Al Viro 已提交
2383 2384
void __audit_mq_sendrecv(mqd_t mqdes, size_t msg_len, unsigned int msg_prio,
			const struct timespec *abs_timeout)
2385 2386
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2387
	struct timespec *p = &context->mq_sendrecv.abs_timeout;
2388

A
Al Viro 已提交
2389 2390 2391 2392
	if (abs_timeout)
		memcpy(p, abs_timeout, sizeof(struct timespec));
	else
		memset(p, 0, sizeof(struct timespec));
2393

A
Al Viro 已提交
2394 2395 2396
	context->mq_sendrecv.mqdes = mqdes;
	context->mq_sendrecv.msg_len = msg_len;
	context->mq_sendrecv.msg_prio = msg_prio;
2397

A
Al Viro 已提交
2398
	context->type = AUDIT_MQ_SENDRECV;
2399 2400 2401 2402 2403
}

/**
 * __audit_mq_notify - record audit data for a POSIX MQ notify
 * @mqdes: MQ descriptor
R
Randy Dunlap 已提交
2404
 * @notification: Notification event
2405 2406 2407
 *
 */

A
Al Viro 已提交
2408
void __audit_mq_notify(mqd_t mqdes, const struct sigevent *notification)
2409 2410 2411
{
	struct audit_context *context = current->audit_context;

A
Al Viro 已提交
2412 2413 2414 2415
	if (notification)
		context->mq_notify.sigev_signo = notification->sigev_signo;
	else
		context->mq_notify.sigev_signo = 0;
2416

A
Al Viro 已提交
2417 2418
	context->mq_notify.mqdes = mqdes;
	context->type = AUDIT_MQ_NOTIFY;
2419 2420 2421 2422 2423 2424 2425 2426
}

/**
 * __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
2427
void __audit_mq_getsetattr(mqd_t mqdes, struct mq_attr *mqstat)
2428 2429
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2430 2431 2432
	context->mq_getsetattr.mqdes = mqdes;
	context->mq_getsetattr.mqstat = *mqstat;
	context->type = AUDIT_MQ_GETSETATTR;
2433 2434
}

2435
/**
S
Steve Grubb 已提交
2436 2437 2438 2439
 * audit_ipc_obj - record audit data for ipc object
 * @ipcp: ipc permissions
 *
 */
A
Al Viro 已提交
2440
void __audit_ipc_obj(struct kern_ipc_perm *ipcp)
S
Steve Grubb 已提交
2441 2442
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2443 2444 2445
	context->ipc.uid = ipcp->uid;
	context->ipc.gid = ipcp->gid;
	context->ipc.mode = ipcp->mode;
A
Al Viro 已提交
2446
	context->ipc.has_perm = 0;
A
Al Viro 已提交
2447 2448
	security_ipc_getsecid(ipcp, &context->ipc.osid);
	context->type = AUDIT_IPC;
S
Steve Grubb 已提交
2449 2450 2451 2452
}

/**
 * audit_ipc_set_perm - record audit data for new ipc permissions
2453 2454 2455 2456 2457
 * @qbytes: msgq bytes
 * @uid: msgq user id
 * @gid: msgq group id
 * @mode: msgq mode (permissions)
 *
A
Al Viro 已提交
2458
 * Called only after audit_ipc_obj().
2459
 */
A
Al Viro 已提交
2460
void __audit_ipc_set_perm(unsigned long qbytes, uid_t uid, gid_t gid, umode_t mode)
L
Linus Torvalds 已提交
2461 2462 2463
{
	struct audit_context *context = current->audit_context;

A
Al Viro 已提交
2464 2465 2466 2467 2468
	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
2469
}
2470

2471
int __audit_bprm(struct linux_binprm *bprm)
A
Al Viro 已提交
2472 2473 2474 2475
{
	struct audit_aux_data_execve *ax;
	struct audit_context *context = current->audit_context;

P
Peter Zijlstra 已提交
2476
	ax = kmalloc(sizeof(*ax), GFP_KERNEL);
A
Al Viro 已提交
2477 2478 2479 2480 2481
	if (!ax)
		return -ENOMEM;

	ax->argc = bprm->argc;
	ax->envc = bprm->envc;
P
Peter Zijlstra 已提交
2482
	ax->mm = bprm->mm;
A
Al Viro 已提交
2483 2484 2485 2486 2487 2488 2489
	ax->d.type = AUDIT_EXECVE;
	ax->d.next = context->aux;
	context->aux = (void *)ax;
	return 0;
}


2490 2491
/**
 * audit_socketcall - record audit data for sys_socketcall
2492
 * @nargs: number of args, which should not be more than AUDITSC_ARGS.
2493 2494 2495
 * @args: args array
 *
 */
2496
int __audit_socketcall(int nargs, unsigned long *args)
2497 2498 2499
{
	struct audit_context *context = current->audit_context;

2500 2501
	if (nargs <= 0 || nargs > AUDITSC_ARGS || !args)
		return -EINVAL;
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
	return 0;
2506 2507
}

A
Al Viro 已提交
2508 2509 2510 2511 2512 2513
/**
 * __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
2514
void __audit_fd_pair(int fd1, int fd2)
A
Al Viro 已提交
2515 2516
{
	struct audit_context *context = current->audit_context;
A
Al Viro 已提交
2517 2518
	context->fds[0] = fd1;
	context->fds[1] = fd2;
A
Al Viro 已提交
2519 2520
}

2521 2522 2523 2524 2525 2526 2527
/**
 * 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.
 */
2528
int __audit_sockaddr(int len, void *a)
2529 2530 2531
{
	struct audit_context *context = current->audit_context;

2532 2533 2534 2535 2536 2537
	if (!context->sockaddr) {
		void *p = kmalloc(sizeof(struct sockaddr_storage), GFP_KERNEL);
		if (!p)
			return -ENOMEM;
		context->sockaddr = p;
	}
2538

2539 2540
	context->sockaddr_len = len;
	memcpy(context->sockaddr, a, len);
2541 2542 2543
	return 0;
}

A
Al Viro 已提交
2544 2545 2546 2547 2548
void __audit_ptrace(struct task_struct *t)
{
	struct audit_context *context = current->audit_context;

	context->target_pid = t->pid;
2549
	context->target_auid = audit_get_loginuid(t);
2550
	context->target_uid = task_uid(t);
2551
	context->target_sessionid = audit_get_sessionid(t);
2552
	security_task_getsecid(t, &context->target_sid);
2553
	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
A
Al Viro 已提交
2554 2555
}

2556 2557 2558 2559 2560 2561 2562 2563
/**
 * 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
2564
int __audit_signal_info(int sig, struct task_struct *t)
2565
{
A
Amy Griffis 已提交
2566 2567 2568
	struct audit_aux_data_pids *axp;
	struct task_struct *tsk = current;
	struct audit_context *ctx = tsk->audit_context;
2569
	kuid_t uid = current_uid(), t_uid = task_uid(t);
2570

A
Al Viro 已提交
2571
	if (audit_pid && t->tgid == audit_pid) {
2572
		if (sig == SIGTERM || sig == SIGHUP || sig == SIGUSR1 || sig == SIGUSR2) {
A
Al Viro 已提交
2573
			audit_sig_pid = tsk->pid;
2574
			if (uid_valid(tsk->loginuid))
A
Al Viro 已提交
2575
				audit_sig_uid = tsk->loginuid;
A
Al Viro 已提交
2576
			else
2577
				audit_sig_uid = uid;
2578
			security_task_getsecid(tsk, &audit_sig_sid);
A
Al Viro 已提交
2579 2580 2581
		}
		if (!audit_signals || audit_dummy_context())
			return 0;
2582
	}
A
Amy Griffis 已提交
2583 2584 2585 2586 2587

	/* optimize the common case by putting first signal recipient directly
	 * in audit_context */
	if (!ctx->target_pid) {
		ctx->target_pid = t->tgid;
2588
		ctx->target_auid = audit_get_loginuid(t);
2589
		ctx->target_uid = t_uid;
2590
		ctx->target_sessionid = audit_get_sessionid(t);
2591
		security_task_getsecid(t, &ctx->target_sid);
2592
		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
A
Amy Griffis 已提交
2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605
		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;
	}
2606
	BUG_ON(axp->pid_count >= AUDIT_AUX_PIDS);
A
Amy Griffis 已提交
2607 2608

	axp->target_pid[axp->pid_count] = t->tgid;
2609
	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
2610
	axp->target_uid[axp->pid_count] = t_uid;
2611
	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
2612
	security_task_getsecid(t, &axp->target_sid[axp->pid_count]);
2613
	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
A
Amy Griffis 已提交
2614 2615 2616
	axp->pid_count++;

	return 0;
2617
}
S
Steve Grubb 已提交
2618

2619 2620
/**
 * __audit_log_bprm_fcaps - store information about a loading bprm and relevant fcaps
D
David Howells 已提交
2621 2622 2623
 * @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)
2676 2677
{
	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;
}

2693
static void audit_log_task(struct audit_buffer *ab)
2694
{
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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
2722
 * @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);
2738 2739
	if (unlikely(!ab))
		return;
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	audit_log_abend(ab, "memory violation", signr);
	audit_log_end(ab);
}
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2744
void __audit_seccomp(unsigned long syscall, long signr, int code)
2745 2746 2747
{
	struct audit_buffer *ab;

2748 2749 2750 2751 2752
	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_SECCOMP);
	if (unlikely(!ab))
		return;
	audit_log_task(ab);
	audit_log_format(ab, " sig=%ld", signr);
2753
	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;
}