Initial import of modified Linux 2.6.28 tree

Original upstream URL:
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git | branch linux-2.6.28.y

1 files changed, 1520 insertions, 0 deletions

diff --git a/kernel/audit.c b/kernel/audit.c
new file mode 100644
index 0000000..ce6d8ea
--- /dev/null
+++ b/kernel/audit.c
@@ -0,0 +1,1520 @@
+/* audit.c -- Auditing support
+ * Gateway between the kernel (e.g., selinux) and the user-space audit daemon.
+ * System-call specific features have moved to auditsc.c
+ *
+ * Copyright 2003-2007 Red Hat Inc., Durham, North Carolina.
+ * 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>
+ *
+ * Goals: 1) Integrate fully with Security Modules.
+ *	  2) Minimal run-time overhead:
+ *	     a) Minimal when syscall auditing is disabled (audit_enable=0).
+ *	     b) Small when syscall auditing is enabled and no audit record
+ *		is generated (defer as much work as possible to record
+ *		generation time):
+ *		i) context is allocated,
+ *		ii) names from getname are stored without a copy, and
+ *		iii) inode information stored from path_lookup.
+ *	  3) Ability to disable syscall auditing at boot time (audit=0).
+ *	  4) Usable by other parts of the kernel (if audit_log* is called,
+ *	     then a syscall record will be generated automatically for the
+ *	     current syscall).
+ *	  5) Netlink interface to user-space.
+ *	  6) Support low-overhead kernel-based filtering to minimize the
+ *	     information that must be passed to user-space.
+ *
+ * Example user-space utilities: http://people.redhat.com/sgrubb/audit/
+ */
+
+#include <linux/init.h>
+#include <asm/types.h>
+#include <asm/atomic.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/kthread.h>
+
+#include <linux/audit.h>
+
+#include <net/sock.h>
+#include <net/netlink.h>
+#include <linux/skbuff.h>
+#include <linux/netlink.h>
+#include <linux/inotify.h>
+#include <linux/freezer.h>
+#include <linux/tty.h>
+
+#include "audit.h"
+
+/* No auditing will take place until audit_initialized == AUDIT_INITIALIZED.
+ * (Initialization happens after skb_init is called.) */
+#define AUDIT_DISABLED		-1
+#define AUDIT_UNINITIALIZED	0
+#define AUDIT_INITIALIZED	1
+static int	audit_initialized;
+
+#define AUDIT_OFF	0
+#define AUDIT_ON	1
+#define AUDIT_LOCKED	2
+int		audit_enabled;
+int		audit_ever_enabled;
+
+/* Default state when kernel boots without any parameters. */
+static int	audit_default;
+
+/* If auditing cannot proceed, audit_failure selects what happens. */
+static int	audit_failure = AUDIT_FAIL_PRINTK;
+
+/*
+ * If audit records are to be written to the netlink socket, audit_pid
+ * contains the pid of the auditd process and audit_nlk_pid contains
+ * the pid to use to send netlink messages to that process.
+ */
+int		audit_pid;
+static int	audit_nlk_pid;
+
+/* If audit_rate_limit is non-zero, limit the rate of sending audit records
+ * to that number per second.  This prevents DoS attacks, but results in
+ * audit records being dropped. */
+static int	audit_rate_limit;
+
+/* Number of outstanding audit_buffers allowed. */
+static int	audit_backlog_limit = 64;
+static int	audit_backlog_wait_time = 60 * HZ;
+static int	audit_backlog_wait_overflow = 0;
+
+/* The identity of the user shutting down the audit system. */
+uid_t		audit_sig_uid = -1;
+pid_t		audit_sig_pid = -1;
+u32		audit_sig_sid = 0;
+
+/* Records can be lost in several ways:
+   0) [suppressed in audit_alloc]
+   1) out of memory in audit_log_start [kmalloc of struct audit_buffer]
+   2) out of memory in audit_log_move [alloc_skb]
+   3) suppressed due to audit_rate_limit
+   4) suppressed due to audit_backlog_limit
+*/
+static atomic_t    audit_lost = ATOMIC_INIT(0);
+
+/* The netlink socket. */
+static struct sock *audit_sock;
+
+/* Inotify handle. */
+struct inotify_handle *audit_ih;
+
+/* Hash for inode-based rules */
+struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
+
+/* The audit_freelist is a list of pre-allocated audit buffers (if more
+ * than AUDIT_MAXFREE are in use, the audit buffer is freed instead of
+ * being placed on the freelist). */
+static DEFINE_SPINLOCK(audit_freelist_lock);
+static int	   audit_freelist_count;
+static LIST_HEAD(audit_freelist);
+
+static struct sk_buff_head audit_skb_queue;
+/* queue of skbs to send to auditd when/if it comes back */
+static struct sk_buff_head audit_skb_hold_queue;
+static struct task_struct *kauditd_task;
+static DECLARE_WAIT_QUEUE_HEAD(kauditd_wait);
+static DECLARE_WAIT_QUEUE_HEAD(audit_backlog_wait);
+
+/* Serialize requests from userspace. */
+static DEFINE_MUTEX(audit_cmd_mutex);
+
+/* AUDIT_BUFSIZ is the size of the temporary buffer used for formatting
+ * audit records.  Since printk uses a 1024 byte buffer, this buffer
+ * should be at least that large. */
+#define AUDIT_BUFSIZ 1024
+
+/* AUDIT_MAXFREE is the number of empty audit_buffers we keep on the
+ * audit_freelist.  Doing so eliminates many kmalloc/kfree calls. */
+#define AUDIT_MAXFREE  (2*NR_CPUS)
+
+/* The audit_buffer is used when formatting an audit record.  The caller
+ * locks briefly to get the record off the freelist or to allocate the
+ * buffer, and locks briefly to send the buffer to the netlink layer or
+ * to place it on a transmit queue.  Multiple audit_buffers can be in
+ * use simultaneously. */
+struct audit_buffer {
+	struct list_head     list;
+	struct sk_buff       *skb;	/* formatted skb ready to send */
+	struct audit_context *ctx;	/* NULL or associated context */
+	gfp_t		     gfp_mask;
+};
+
+struct audit_reply {
+	int pid;
+	struct sk_buff *skb;
+};
+
+static void audit_set_pid(struct audit_buffer *ab, pid_t pid)
+{
+	if (ab) {
+		struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
+		nlh->nlmsg_pid = pid;
+	}
+}
+
+void audit_panic(const char *message)
+{
+	switch (audit_failure)
+	{
+	case AUDIT_FAIL_SILENT:
+		break;
+	case AUDIT_FAIL_PRINTK:
+		if (printk_ratelimit())
+			printk(KERN_ERR "audit: %s\n", message);
+		break;
+	case AUDIT_FAIL_PANIC:
+		/* test audit_pid since printk is always losey, why bother? */
+		if (audit_pid)
+			panic("audit: %s\n", message);
+		break;
+	}
+}
+
+static inline int audit_rate_check(void)
+{
+	static unsigned long	last_check = 0;
+	static int		messages   = 0;
+	static DEFINE_SPINLOCK(lock);
+	unsigned long		flags;
+	unsigned long		now;
+	unsigned long		elapsed;
+	int			retval	   = 0;
+
+	if (!audit_rate_limit) return 1;
+
+	spin_lock_irqsave(&lock, flags);
+	if (++messages < audit_rate_limit) {
+		retval = 1;
+	} else {
+		now     = jiffies;
+		elapsed = now - last_check;
+		if (elapsed > HZ) {
+			last_check = now;
+			messages   = 0;
+			retval     = 1;
+		}
+	}
+	spin_unlock_irqrestore(&lock, flags);
+
+	return retval;
+}
+
+/**
+ * audit_log_lost - conditionally log lost audit message event
+ * @message: the message stating reason for lost audit message
+ *
+ * Emit at least 1 message per second, even if audit_rate_check is
+ * throttling.
+ * Always increment the lost messages counter.
+*/
+void audit_log_lost(const char *message)
+{
+	static unsigned long	last_msg = 0;
+	static DEFINE_SPINLOCK(lock);
+	unsigned long		flags;
+	unsigned long		now;
+	int			print;
+
+	atomic_inc(&audit_lost);
+
+	print = (audit_failure == AUDIT_FAIL_PANIC || !audit_rate_limit);
+
+	if (!print) {
+		spin_lock_irqsave(&lock, flags);
+		now = jiffies;
+		if (now - last_msg > HZ) {
+			print = 1;
+			last_msg = now;
+		}
+		spin_unlock_irqrestore(&lock, flags);
+	}
+
+	if (print) {
+		if (printk_ratelimit())
+			printk(KERN_WARNING
+				"audit: audit_lost=%d audit_rate_limit=%d "
+				"audit_backlog_limit=%d\n",
+				atomic_read(&audit_lost),
+				audit_rate_limit,
+				audit_backlog_limit);
+		audit_panic(message);
+	}
+}
+
+static int audit_log_config_change(char *function_name, int new, int old,
+				   uid_t loginuid, u32 sessionid, u32 sid,
+				   int allow_changes)
+{
+	struct audit_buffer *ab;
+	int rc = 0;
+
+	ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
+	audit_log_format(ab, "%s=%d old=%d auid=%u ses=%u", function_name, new,
+			 old, loginuid, sessionid);
+	if (sid) {
+		char *ctx = NULL;
+		u32 len;
+
+		rc = security_secid_to_secctx(sid, &ctx, &len);
+		if (rc) {
+			audit_log_format(ab, " sid=%u", sid);
+			allow_changes = 0; /* Something weird, deny request */
+		} else {
+			audit_log_format(ab, " subj=%s", ctx);
+			security_release_secctx(ctx, len);
+		}
+	}
+	audit_log_format(ab, " res=%d", allow_changes);
+	audit_log_end(ab);
+	return rc;
+}
+
+static int audit_do_config_change(char *function_name, int *to_change,
+				  int new, uid_t loginuid, u32 sessionid,
+				  u32 sid)
+{
+	int allow_changes, rc = 0, old = *to_change;
+
+	/* check if we are locked */
+	if (audit_enabled == AUDIT_LOCKED)
+		allow_changes = 0;
+	else
+		allow_changes = 1;
+
+	if (audit_enabled != AUDIT_OFF) {
+		rc = audit_log_config_change(function_name, new, old, loginuid,
+					     sessionid, sid, allow_changes);
+		if (rc)
+			allow_changes = 0;
+	}
+
+	/* If we are allowed, make the change */
+	if (allow_changes == 1)
+		*to_change = new;
+	/* Not allowed, update reason */
+	else if (rc == 0)
+		rc = -EPERM;
+	return rc;
+}
+
+static int audit_set_rate_limit(int limit, uid_t loginuid, u32 sessionid,
+				u32 sid)
+{
+	return audit_do_config_change("audit_rate_limit", &audit_rate_limit,
+				      limit, loginuid, sessionid, sid);
+}
+
+static int audit_set_backlog_limit(int limit, uid_t loginuid, u32 sessionid,
+				   u32 sid)
+{
+	return audit_do_config_change("audit_backlog_limit", &audit_backlog_limit,
+				      limit, loginuid, sessionid, sid);
+}
+
+static int audit_set_enabled(int state, uid_t loginuid, u32 sessionid, u32 sid)
+{
+	int rc;
+	if (state < AUDIT_OFF || state > AUDIT_LOCKED)
+		return -EINVAL;
+
+	rc =  audit_do_config_change("audit_enabled", &audit_enabled, state,
+				     loginuid, sessionid, sid);
+
+	if (!rc)
+		audit_ever_enabled |= !!state;
+
+	return rc;
+}
+
+static int audit_set_failure(int state, uid_t loginuid, u32 sessionid, u32 sid)
+{
+	if (state != AUDIT_FAIL_SILENT
+	    && state != AUDIT_FAIL_PRINTK
+	    && state != AUDIT_FAIL_PANIC)
+		return -EINVAL;
+
+	return audit_do_config_change("audit_failure", &audit_failure, state,
+				      loginuid, sessionid, sid);
+}
+
+/*
+ * Queue skbs to be sent to auditd when/if it comes back.  These skbs should
+ * already have been sent via prink/syslog and so if these messages are dropped
+ * it is not a huge concern since we already passed the audit_log_lost()
+ * notification and stuff.  This is just nice to get audit messages during
+ * boot before auditd is running or messages generated while auditd is stopped.
+ * This only holds messages is audit_default is set, aka booting with audit=1
+ * or building your kernel that way.
+ */
+static void audit_hold_skb(struct sk_buff *skb)
+{
+	if (audit_default &&
+	    skb_queue_len(&audit_skb_hold_queue) < audit_backlog_limit)
+		skb_queue_tail(&audit_skb_hold_queue, skb);
+	else
+		kfree_skb(skb);
+}
+
+static void kauditd_send_skb(struct sk_buff *skb)
+{
+	int err;
+	/* take a reference in case we can't send it and we want to hold it */
+	skb_get(skb);
+	err = netlink_unicast(audit_sock, skb, audit_nlk_pid, 0);
+	if (err < 0) {
+		BUG_ON(err != -ECONNREFUSED); /* Shoudn't happen */
+		printk(KERN_ERR "audit: *NO* daemon at audit_pid=%d\n", audit_pid);
+		audit_log_lost("auditd dissapeared\n");
+		audit_pid = 0;
+		/* we might get lucky and get this in the next auditd */
+		audit_hold_skb(skb);
+	} else
+		/* drop the extra reference if sent ok */
+		kfree_skb(skb);
+}
+
+static int kauditd_thread(void *dummy)
+{
+	struct sk_buff *skb;
+
+	set_freezable();
+	while (!kthread_should_stop()) {
+		/*
+		 * if auditd just started drain the queue of messages already
+		 * sent to syslog/printk.  remember loss here is ok.  we already
+		 * called audit_log_lost() if it didn't go out normally.  so the
+		 * race between the skb_dequeue and the next check for audit_pid
+		 * doesn't matter.
+		 *
+		 * if you ever find kauditd to be too slow we can get a perf win
+		 * by doing our own locking and keeping better track if there
+		 * are messages in this queue.  I don't see the need now, but
+		 * in 5 years when I want to play with this again I'll see this
+		 * note and still have no friggin idea what i'm thinking today.
+		 */
+		if (audit_default && audit_pid) {
+			skb = skb_dequeue(&audit_skb_hold_queue);
+			if (unlikely(skb)) {
+				while (skb && audit_pid) {
+					kauditd_send_skb(skb);
+					skb = skb_dequeue(&audit_skb_hold_queue);
+				}
+			}
+		}
+
+		skb = skb_dequeue(&audit_skb_queue);
+		wake_up(&audit_backlog_wait);
+		if (skb) {
+			if (audit_pid)
+				kauditd_send_skb(skb);
+			else {
+				if (printk_ratelimit())
+					printk(KERN_NOTICE "%s\n", skb->data + NLMSG_SPACE(0));
+				else
+					audit_log_lost("printk limit exceeded\n");
+
+				audit_hold_skb(skb);
+			}
+		} else {
+			DECLARE_WAITQUEUE(wait, current);
+			set_current_state(TASK_INTERRUPTIBLE);
+			add_wait_queue(&kauditd_wait, &wait);
+
+			if (!skb_queue_len(&audit_skb_queue)) {
+				try_to_freeze();
+				schedule();
+			}
+
+			__set_current_state(TASK_RUNNING);
+			remove_wait_queue(&kauditd_wait, &wait);
+		}
+	}
+	return 0;
+}
+
+static int audit_prepare_user_tty(pid_t pid, uid_t loginuid, u32 sessionid)
+{
+	struct task_struct *tsk;
+	int err;
+
+	read_lock(&tasklist_lock);
+	tsk = find_task_by_vpid(pid);
+	err = -ESRCH;
+	if (!tsk)
+		goto out;
+	err = 0;
+
+	spin_lock_irq(&tsk->sighand->siglock);
+	if (!tsk->signal->audit_tty)
+		err = -EPERM;
+	spin_unlock_irq(&tsk->sighand->siglock);
+	if (err)
+		goto out;
+
+	tty_audit_push_task(tsk, loginuid, sessionid);
+out:
+	read_unlock(&tasklist_lock);
+	return err;
+}
+
+int audit_send_list(void *_dest)
+{
+	struct audit_netlink_list *dest = _dest;
+	int pid = dest->pid;
+	struct sk_buff *skb;
+
+	/* wait for parent to finish and send an ACK */
+	mutex_lock(&audit_cmd_mutex);
+	mutex_unlock(&audit_cmd_mutex);
+
+	while ((skb = __skb_dequeue(&dest->q)) != NULL)
+		netlink_unicast(audit_sock, skb, pid, 0);
+
+	kfree(dest);
+
+	return 0;
+}
+
+#ifdef CONFIG_AUDIT_TREE
+static int prune_tree_thread(void *unused)
+{
+	mutex_lock(&audit_cmd_mutex);
+	audit_prune_trees();
+	mutex_unlock(&audit_cmd_mutex);
+	return 0;
+}
+
+void audit_schedule_prune(void)
+{
+	kthread_run(prune_tree_thread, NULL, "audit_prune_tree");
+}
+#endif
+
+struct sk_buff *audit_make_reply(int pid, int seq, int type, int done,
+				 int multi, void *payload, int size)
+{
+	struct sk_buff	*skb;
+	struct nlmsghdr	*nlh;
+	int		len = NLMSG_SPACE(size);
+	void		*data;
+	int		flags = multi ? NLM_F_MULTI : 0;
+	int		t     = done  ? NLMSG_DONE  : type;
+
+	skb = alloc_skb(len, GFP_KERNEL);
+	if (!skb)
+		return NULL;
+
+	nlh		 = NLMSG_PUT(skb, pid, seq, t, size);
+	nlh->nlmsg_flags = flags;
+	data		 = NLMSG_DATA(nlh);
+	memcpy(data, payload, size);
+	return skb;
+
+nlmsg_failure:			/* Used by NLMSG_PUT */
+	if (skb)
+		kfree_skb(skb);
+	return NULL;
+}
+
+static int audit_send_reply_thread(void *arg)
+{
+	struct audit_reply *reply = (struct audit_reply *)arg;
+
+	mutex_lock(&audit_cmd_mutex);
+	mutex_unlock(&audit_cmd_mutex);
+
+	/* Ignore failure. It'll only happen if the sender goes away,
+	   because our timeout is set to infinite. */
+	netlink_unicast(audit_sock, reply->skb, reply->pid, 0);
+	kfree(reply);
+	return 0;
+}
+/**
+ * audit_send_reply - send an audit reply message via netlink
+ * @pid: process id to send reply to
+ * @seq: sequence number
+ * @type: audit message type
+ * @done: done (last) flag
+ * @multi: multi-part message flag
+ * @payload: payload data
+ * @size: payload size
+ *
+ * Allocates an skb, builds the netlink message, and sends it to the pid.
+ * No failure notifications.
+ */
+void audit_send_reply(int pid, int seq, int type, int done, int multi,
+		      void *payload, int size)
+{
+	struct sk_buff *skb;
+	struct task_struct *tsk;
+	struct audit_reply *reply = kmalloc(sizeof(struct audit_reply),
+					    GFP_KERNEL);
+
+	if (!reply)
+		return;
+
+	skb = audit_make_reply(pid, seq, type, done, multi, payload, size);
+	if (!skb)
+		goto out;
+
+	reply->pid = pid;
+	reply->skb = skb;
+
+	tsk = kthread_run(audit_send_reply_thread, reply, "audit_send_reply");
+	if (!IS_ERR(tsk))
+		return;
+	kfree_skb(skb);
+out:
+	kfree(reply);
+}
+
+/*
+ * Check for appropriate CAP_AUDIT_ capabilities on incoming audit
+ * control messages.
+ */
+static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type)
+{
+	int err = 0;
+
+	switch (msg_type) {
+	case AUDIT_GET:
+	case AUDIT_LIST:
+	case AUDIT_LIST_RULES:
+	case AUDIT_SET:
+	case AUDIT_ADD:
+	case AUDIT_ADD_RULE:
+	case AUDIT_DEL:
+	case AUDIT_DEL_RULE:
+	case AUDIT_SIGNAL_INFO:
+	case AUDIT_TTY_GET:
+	case AUDIT_TTY_SET:
+	case AUDIT_TRIM:
+	case AUDIT_MAKE_EQUIV:
+		if (security_netlink_recv(skb, CAP_AUDIT_CONTROL))
+			err = -EPERM;
+		break;
+	case AUDIT_USER:
+	case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
+	case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
+		if (security_netlink_recv(skb, CAP_AUDIT_WRITE))
+			err = -EPERM;
+		break;
+	default:  /* bad msg */
+		err = -EINVAL;
+	}
+
+	return err;
+}
+
+static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type,
+				     u32 pid, u32 uid, uid_t auid, u32 ses,
+				     u32 sid)
+{
+	int rc = 0;
+	char *ctx = NULL;
+	u32 len;
+
+	if (!audit_enabled) {
+		*ab = NULL;
+		return rc;
+	}
+
+	*ab = audit_log_start(NULL, GFP_KERNEL, msg_type);
+	audit_log_format(*ab, "user pid=%d uid=%u auid=%u ses=%u",
+			 pid, uid, auid, ses);
+	if (sid) {
+		rc = security_secid_to_secctx(sid, &ctx, &len);
+		if (rc)
+			audit_log_format(*ab, " ssid=%u", sid);
+		else {
+			audit_log_format(*ab, " subj=%s", ctx);
+			security_release_secctx(ctx, len);
+		}
+	}
+
+	return rc;
+}
+
+static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+	u32			uid, pid, seq, sid;
+	void			*data;
+	struct audit_status	*status_get, status_set;
+	int			err;
+	struct audit_buffer	*ab;
+	u16			msg_type = nlh->nlmsg_type;
+	uid_t			loginuid; /* loginuid of sender */
+	u32			sessionid;
+	struct audit_sig_info   *sig_data;
+	char			*ctx = NULL;
+	u32			len;
+
+	err = audit_netlink_ok(skb, msg_type);
+	if (err)
+		return err;
+
+	/* As soon as there's any sign of userspace auditd,
+	 * start kauditd to talk to it */
+	if (!kauditd_task)
+		kauditd_task = kthread_run(kauditd_thread, NULL, "kauditd");
+	if (IS_ERR(kauditd_task)) {
+		err = PTR_ERR(kauditd_task);
+		kauditd_task = NULL;
+		return err;
+	}
+
+	pid  = NETLINK_CREDS(skb)->pid;
+	uid  = NETLINK_CREDS(skb)->uid;
+	loginuid = NETLINK_CB(skb).loginuid;
+	sessionid = NETLINK_CB(skb).sessionid;
+	sid  = NETLINK_CB(skb).sid;
+	seq  = nlh->nlmsg_seq;
+	data = NLMSG_DATA(nlh);
+
+	switch (msg_type) {
+	case AUDIT_GET:
+		status_set.enabled	 = audit_enabled;
+		status_set.failure	 = audit_failure;
+		status_set.pid		 = audit_pid;
+		status_set.rate_limit	 = audit_rate_limit;
+		status_set.backlog_limit = audit_backlog_limit;
+		status_set.lost		 = atomic_read(&audit_lost);
+		status_set.backlog	 = skb_queue_len(&audit_skb_queue);
+		audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_GET, 0, 0,
+				 &status_set, sizeof(status_set));
+		break;
+	case AUDIT_SET:
+		if (nlh->nlmsg_len < sizeof(struct audit_status))
+			return -EINVAL;
+		status_get   = (struct audit_status *)data;
+		if (status_get->mask & AUDIT_STATUS_ENABLED) {
+			err = audit_set_enabled(status_get->enabled,
+						loginuid, sessionid, sid);
+			if (err < 0)
+				return err;
+		}
+		if (status_get->mask & AUDIT_STATUS_FAILURE) {
+			err = audit_set_failure(status_get->failure,
+						loginuid, sessionid, sid);
+			if (err < 0)
+				return err;
+		}
+		if (status_get->mask & AUDIT_STATUS_PID) {
+			int new_pid = status_get->pid;
+
+			if (audit_enabled != AUDIT_OFF)
+				audit_log_config_change("audit_pid", new_pid,
+							audit_pid, loginuid,
+							sessionid, sid, 1);
+
+			audit_pid = new_pid;
+			audit_nlk_pid = NETLINK_CB(skb).pid;
+		}
+		if (status_get->mask & AUDIT_STATUS_RATE_LIMIT) {
+			err = audit_set_rate_limit(status_get->rate_limit,
+						   loginuid, sessionid, sid);
+			if (err < 0)
+				return err;
+		}
+		if (status_get->mask & AUDIT_STATUS_BACKLOG_LIMIT)
+			err = audit_set_backlog_limit(status_get->backlog_limit,
+						      loginuid, sessionid, sid);
+		break;
+	case AUDIT_USER:
+	case AUDIT_FIRST_USER_MSG ... AUDIT_LAST_USER_MSG:
+	case AUDIT_FIRST_USER_MSG2 ... AUDIT_LAST_USER_MSG2:
+		if (!audit_enabled && msg_type != AUDIT_USER_AVC)
+			return 0;
+
+		err = audit_filter_user(&NETLINK_CB(skb));
+		if (err == 1) {
+			err = 0;
+			if (msg_type == AUDIT_USER_TTY) {
+				err = audit_prepare_user_tty(pid, loginuid,
+							     sessionid);
+				if (err)
+					break;
+			}
+			audit_log_common_recv_msg(&ab, msg_type, pid, uid,
+						  loginuid, sessionid, sid);
+
+			if (msg_type != AUDIT_USER_TTY)
+				audit_log_format(ab, " msg='%.1024s'",
+						 (char *)data);
+			else {
+				int size;
+
+				audit_log_format(ab, " msg=");
+				size = nlmsg_len(nlh);
+				audit_log_n_untrustedstring(ab, data, size);
+			}
+			audit_set_pid(ab, pid);
+			audit_log_end(ab);
+		}
+		break;
+	case AUDIT_ADD:
+	case AUDIT_DEL:
+		if (nlmsg_len(nlh) < sizeof(struct audit_rule))
+			return -EINVAL;
+		if (audit_enabled == AUDIT_LOCKED) {
+			audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
+						  uid, loginuid, sessionid, sid);
+
+			audit_log_format(ab, " audit_enabled=%d res=0",
+					 audit_enabled);
+			audit_log_end(ab);
+			return -EPERM;
+		}
+		/* fallthrough */
+	case AUDIT_LIST:
+		err = audit_receive_filter(msg_type, NETLINK_CB(skb).pid,
+					   uid, seq, data, nlmsg_len(nlh),
+					   loginuid, sessionid, sid);
+		break;
+	case AUDIT_ADD_RULE:
+	case AUDIT_DEL_RULE:
+		if (nlmsg_len(nlh) < sizeof(struct audit_rule_data))
+			return -EINVAL;
+		if (audit_enabled == AUDIT_LOCKED) {
+			audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
+						  uid, loginuid, sessionid, sid);
+
+			audit_log_format(ab, " audit_enabled=%d res=0",
+					 audit_enabled);
+			audit_log_end(ab);
+			return -EPERM;
+		}
+		/* fallthrough */
+	case AUDIT_LIST_RULES:
+		err = audit_receive_filter(msg_type, NETLINK_CB(skb).pid,
+					   uid, seq, data, nlmsg_len(nlh),
+					   loginuid, sessionid, sid);
+		break;
+	case AUDIT_TRIM:
+		audit_trim_trees();
+
+		audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
+					  uid, loginuid, sessionid, sid);
+
+		audit_log_format(ab, " op=trim res=1");
+		audit_log_end(ab);
+		break;
+	case AUDIT_MAKE_EQUIV: {
+		void *bufp = data;
+		u32 sizes[2];
+		size_t msglen = nlmsg_len(nlh);
+		char *old, *new;
+
+		err = -EINVAL;
+		if (msglen < 2 * sizeof(u32))
+			break;
+		memcpy(sizes, bufp, 2 * sizeof(u32));
+		bufp += 2 * sizeof(u32);
+		msglen -= 2 * sizeof(u32);
+		old = audit_unpack_string(&bufp, &msglen, sizes[0]);
+		if (IS_ERR(old)) {
+			err = PTR_ERR(old);
+			break;
+		}
+		new = audit_unpack_string(&bufp, &msglen, sizes[1]);
+		if (IS_ERR(new)) {
+			err = PTR_ERR(new);
+			kfree(old);
+			break;
+		}
+		/* OK, here comes... */
+		err = audit_tag_tree(old, new);
+
+		audit_log_common_recv_msg(&ab, AUDIT_CONFIG_CHANGE, pid,
+					  uid, loginuid, sessionid, sid);
+
+		audit_log_format(ab, " op=make_equiv old=");
+		audit_log_untrustedstring(ab, old);
+		audit_log_format(ab, " new=");
+		audit_log_untrustedstring(ab, new);
+		audit_log_format(ab, " res=%d", !err);
+		audit_log_end(ab);
+		kfree(old);
+		kfree(new);
+		break;
+	}
+	case AUDIT_SIGNAL_INFO:
+		err = security_secid_to_secctx(audit_sig_sid, &ctx, &len);
+		if (err)
+			return err;
+		sig_data = kmalloc(sizeof(*sig_data) + len, GFP_KERNEL);
+		if (!sig_data) {
+			security_release_secctx(ctx, len);
+			return -ENOMEM;
+		}
+		sig_data->uid = audit_sig_uid;
+		sig_data->pid = audit_sig_pid;
+		memcpy(sig_data->ctx, ctx, len);
+		security_release_secctx(ctx, len);
+		audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_SIGNAL_INFO,
+				0, 0, sig_data, sizeof(*sig_data) + len);
+		kfree(sig_data);
+		break;
+	case AUDIT_TTY_GET: {
+		struct audit_tty_status s;
+		struct task_struct *tsk;
+
+		read_lock(&tasklist_lock);
+		tsk = find_task_by_vpid(pid);
+		if (!tsk)
+			err = -ESRCH;
+		else {
+			spin_lock_irq(&tsk->sighand->siglock);
+			s.enabled = tsk->signal->audit_tty != 0;
+			spin_unlock_irq(&tsk->sighand->siglock);
+		}
+		read_unlock(&tasklist_lock);
+		audit_send_reply(NETLINK_CB(skb).pid, seq, AUDIT_TTY_GET, 0, 0,
+				 &s, sizeof(s));
+		break;
+	}
+	case AUDIT_TTY_SET: {
+		struct audit_tty_status *s;
+		struct task_struct *tsk;
+
+		if (nlh->nlmsg_len < sizeof(struct audit_tty_status))
+			return -EINVAL;
+		s = data;
+		if (s->enabled != 0 && s->enabled != 1)
+			return -EINVAL;
+		read_lock(&tasklist_lock);
+		tsk = find_task_by_vpid(pid);
+		if (!tsk)
+			err = -ESRCH;
+		else {
+			spin_lock_irq(&tsk->sighand->siglock);
+			tsk->signal->audit_tty = s->enabled != 0;
+			spin_unlock_irq(&tsk->sighand->siglock);
+		}
+		read_unlock(&tasklist_lock);
+		break;
+	}
+	default:
+		err = -EINVAL;
+		break;
+	}
+
+	return err < 0 ? err : 0;
+}
+
+/*
+ * Get message from skb (based on rtnetlink_rcv_skb).  Each message is
+ * processed by audit_receive_msg.  Malformed skbs with wrong length are
+ * discarded silently.
+ */
+static void audit_receive_skb(struct sk_buff *skb)
+{
+	int		err;
+	struct nlmsghdr	*nlh;
+	u32		rlen;
+
+	while (skb->len >= NLMSG_SPACE(0)) {
+		nlh = nlmsg_hdr(skb);
+		if (nlh->nlmsg_len < sizeof(*nlh) || skb->len < nlh->nlmsg_len)
+			return;
+		rlen = NLMSG_ALIGN(nlh->nlmsg_len);
+		if (rlen > skb->len)
+			rlen = skb->len;
+		if ((err = audit_receive_msg(skb, nlh))) {
+			netlink_ack(skb, nlh, err);
+		} else if (nlh->nlmsg_flags & NLM_F_ACK)
+			netlink_ack(skb, nlh, 0);
+		skb_pull(skb, rlen);
+	}
+}
+
+/* Receive messages from netlink socket. */
+static void audit_receive(struct sk_buff  *skb)
+{
+	mutex_lock(&audit_cmd_mutex);
+	audit_receive_skb(skb);
+	mutex_unlock(&audit_cmd_mutex);
+}
+
+#ifdef CONFIG_AUDITSYSCALL
+static const struct inotify_operations audit_inotify_ops = {
+	.handle_event	= audit_handle_ievent,
+	.destroy_watch	= audit_free_parent,
+};
+#endif
+
+/* Initialize audit support at boot time. */
+static int __init audit_init(void)
+{
+	int i;
+
+	if (audit_initialized == AUDIT_DISABLED)
+		return 0;
+
+	printk(KERN_INFO "audit: initializing netlink socket (%s)\n",
+	       audit_default ? "enabled" : "disabled");
+	audit_sock = netlink_kernel_create(&init_net, NETLINK_AUDIT, 0,
+					   audit_receive, NULL, THIS_MODULE);
+	if (!audit_sock)
+		audit_panic("cannot initialize netlink socket");
+	else
+		audit_sock->sk_sndtimeo = MAX_SCHEDULE_TIMEOUT;
+
+	skb_queue_head_init(&audit_skb_queue);
+	skb_queue_head_init(&audit_skb_hold_queue);
+	audit_initialized = AUDIT_INITIALIZED;
+	audit_enabled = audit_default;
+	audit_ever_enabled |= !!audit_default;
+
+	audit_log(NULL, GFP_KERNEL, AUDIT_KERNEL, "initialized");
+
+#ifdef CONFIG_AUDITSYSCALL
+	audit_ih = inotify_init(&audit_inotify_ops);
+	if (IS_ERR(audit_ih))
+		audit_panic("cannot initialize inotify handle");
+#endif
+
+	for (i = 0; i < AUDIT_INODE_BUCKETS; i++)
+		INIT_LIST_HEAD(&audit_inode_hash[i]);
+
+	return 0;
+}
+__initcall(audit_init);
+
+/* Process kernel command-line parameter at boot time.  audit=0 or audit=1. */
+static int __init audit_enable(char *str)
+{
+	audit_default = !!simple_strtol(str, NULL, 0);
+	if (!audit_default)
+		audit_initialized = AUDIT_DISABLED;
+
+	printk(KERN_INFO "audit: %s", audit_default ? "enabled" : "disabled");
+
+	if (audit_initialized == AUDIT_INITIALIZED) {
+		audit_enabled = audit_default;
+		audit_ever_enabled |= !!audit_default;
+	} else if (audit_initialized == AUDIT_UNINITIALIZED) {
+		printk(" (after initialization)");
+	} else {
+		printk(" (until reboot)");
+	}
+	printk("\n");
+
+	return 1;
+}
+
+__setup("audit=", audit_enable);
+
+static void audit_buffer_free(struct audit_buffer *ab)
+{
+	unsigned long flags;
+
+	if (!ab)
+		return;
+
+	if (ab->skb)
+		kfree_skb(ab->skb);
+
+	spin_lock_irqsave(&audit_freelist_lock, flags);
+	if (audit_freelist_count > AUDIT_MAXFREE)
+		kfree(ab);
+	else {
+		audit_freelist_count++;
+		list_add(&ab->list, &audit_freelist);
+	}
+	spin_unlock_irqrestore(&audit_freelist_lock, flags);
+}
+
+static struct audit_buffer * audit_buffer_alloc(struct audit_context *ctx,
+						gfp_t gfp_mask, int type)
+{
+	unsigned long flags;
+	struct audit_buffer *ab = NULL;
+	struct nlmsghdr *nlh;
+
+	spin_lock_irqsave(&audit_freelist_lock, flags);
+	if (!list_empty(&audit_freelist)) {
+		ab = list_entry(audit_freelist.next,
+				struct audit_buffer, list);
+		list_del(&ab->list);
+		--audit_freelist_count;
+	}
+	spin_unlock_irqrestore(&audit_freelist_lock, flags);
+
+	if (!ab) {
+		ab = kmalloc(sizeof(*ab), gfp_mask);
+		if (!ab)
+			goto err;
+	}
+
+	ab->skb = alloc_skb(AUDIT_BUFSIZ, gfp_mask);
+	if (!ab->skb)
+		goto err;
+
+	ab->ctx = ctx;
+	ab->gfp_mask = gfp_mask;
+	nlh = (struct nlmsghdr *)skb_put(ab->skb, NLMSG_SPACE(0));
+	nlh->nlmsg_type = type;
+	nlh->nlmsg_flags = 0;
+	nlh->nlmsg_pid = 0;
+	nlh->nlmsg_seq = 0;
+	return ab;
+err:
+	audit_buffer_free(ab);
+	return NULL;
+}
+
+/**
+ * audit_serial - compute a serial number for the audit record
+ *
+ * Compute a serial number for the audit record.  Audit records are
+ * written to user-space as soon as they are generated, so a complete
+ * audit record may be written in several pieces.  The timestamp of the
+ * record and this serial number are used by the user-space tools to
+ * determine which pieces belong to the same audit record.  The
+ * (timestamp,serial) tuple is unique for each syscall and is live from
+ * syscall entry to syscall exit.
+ *
+ * NOTE: Another possibility is to store the formatted records off the
+ * audit context (for those records that have a context), and emit them
+ * all at syscall exit.  However, this could delay the reporting of
+ * significant errors until syscall exit (or never, if the system
+ * halts).
+ */
+unsigned int audit_serial(void)
+{
+	static DEFINE_SPINLOCK(serial_lock);
+	static unsigned int serial = 0;
+
+	unsigned long flags;
+	unsigned int ret;
+
+	spin_lock_irqsave(&serial_lock, flags);
+	do {
+		ret = ++serial;
+	} while (unlikely(!ret));
+	spin_unlock_irqrestore(&serial_lock, flags);
+
+	return ret;
+}
+
+static inline void audit_get_stamp(struct audit_context *ctx,
+				   struct timespec *t, unsigned int *serial)
+{
+	if (!ctx || !auditsc_get_stamp(ctx, t, serial)) {
+		*t = CURRENT_TIME;
+		*serial = audit_serial();
+	}
+}
+
+/* Obtain an audit buffer.  This routine does locking to obtain the
+ * audit buffer, but then no locking is required for calls to
+ * audit_log_*format.  If the tsk is a task that is currently in a
+ * syscall, then the syscall is marked as auditable and an audit record
+ * will be written at syscall exit.  If there is no associated task, tsk
+ * should be NULL. */
+
+/**
+ * audit_log_start - obtain an audit buffer
+ * @ctx: audit_context (may be NULL)
+ * @gfp_mask: type of allocation
+ * @type: audit message type
+ *
+ * Returns audit_buffer pointer on success or NULL on error.
+ *
+ * Obtain an audit buffer.  This routine does locking to obtain the
+ * audit buffer, but then no locking is required for calls to
+ * audit_log_*format.  If the task (ctx) is a task that is currently in a
+ * syscall, then the syscall is marked as auditable and an audit record
+ * will be written at syscall exit.  If there is no associated task, then
+ * task context (ctx) should be NULL.
+ */
+struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
+				     int type)
+{
+	struct audit_buffer	*ab	= NULL;
+	struct timespec		t;
+	unsigned int		uninitialized_var(serial);
+	int reserve;
+	unsigned long timeout_start = jiffies;
+
+	if (audit_initialized != AUDIT_INITIALIZED)
+		return NULL;
+
+	if (unlikely(audit_filter_type(type)))
+		return NULL;
+
+	if (gfp_mask & __GFP_WAIT)
+		reserve = 0;
+	else
+		reserve = 5; /* Allow atomic callers to go up to five
+				entries over the normal backlog limit */
+
+	while (audit_backlog_limit
+	       && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) {
+		if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time
+		    && time_before(jiffies, timeout_start + audit_backlog_wait_time)) {
+
+			/* Wait for auditd to drain the queue a little */
+			DECLARE_WAITQUEUE(wait, current);
+			set_current_state(TASK_INTERRUPTIBLE);
+			add_wait_queue(&audit_backlog_wait, &wait);
+
+			if (audit_backlog_limit &&
+			    skb_queue_len(&audit_skb_queue) > audit_backlog_limit)
+				schedule_timeout(timeout_start + audit_backlog_wait_time - jiffies);
+
+			__set_current_state(TASK_RUNNING);
+			remove_wait_queue(&audit_backlog_wait, &wait);
+			continue;
+		}
+		if (audit_rate_check() && printk_ratelimit())
+			printk(KERN_WARNING
+			       "audit: audit_backlog=%d > "
+			       "audit_backlog_limit=%d\n",
+			       skb_queue_len(&audit_skb_queue),
+			       audit_backlog_limit);
+		audit_log_lost("backlog limit exceeded");
+		audit_backlog_wait_time = audit_backlog_wait_overflow;
+		wake_up(&audit_backlog_wait);
+		return NULL;
+	}
+
+	ab = audit_buffer_alloc(ctx, gfp_mask, type);
+	if (!ab) {
+		audit_log_lost("out of memory in audit_log_start");
+		return NULL;
+	}
+
+	audit_get_stamp(ab->ctx, &t, &serial);
+
+	audit_log_format(ab, "audit(%lu.%03lu:%u): ",
+			 t.tv_sec, t.tv_nsec/1000000, serial);
+	return ab;
+}
+
+/**
+ * audit_expand - expand skb in the audit buffer
+ * @ab: audit_buffer
+ * @extra: space to add at tail of the skb
+ *
+ * Returns 0 (no space) on failed expansion, or available space if
+ * successful.
+ */
+static inline int audit_expand(struct audit_buffer *ab, int extra)
+{
+	struct sk_buff *skb = ab->skb;
+	int oldtail = skb_tailroom(skb);
+	int ret = pskb_expand_head(skb, 0, extra, ab->gfp_mask);
+	int newtail = skb_tailroom(skb);
+
+	if (ret < 0) {
+		audit_log_lost("out of memory in audit_expand");
+		return 0;
+	}
+
+	skb->truesize += newtail - oldtail;
+	return newtail;
+}
+
+/*
+ * Format an audit message into the audit buffer.  If there isn't enough
+ * room in the audit buffer, more room will be allocated and vsnprint
+ * will be called a second time.  Currently, we assume that a printk
+ * can't format message larger than 1024 bytes, so we don't either.
+ */
+static void audit_log_vformat(struct audit_buffer *ab, const char *fmt,
+			      va_list args)
+{
+	int len, avail;
+	struct sk_buff *skb;
+	va_list args2;
+
+	if (!ab)
+		return;
+
+	BUG_ON(!ab->skb);
+	skb = ab->skb;
+	avail = skb_tailroom(skb);
+	if (avail == 0) {
+		avail = audit_expand(ab, AUDIT_BUFSIZ);
+		if (!avail)
+			goto out;
+	}
+	va_copy(args2, args);
+	len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args);
+	if (len >= avail) {
+		/* The printk buffer is 1024 bytes long, so if we get
+		 * here and AUDIT_BUFSIZ is at least 1024, then we can
+		 * log everything that printk could have logged. */
+		avail = audit_expand(ab,
+			max_t(unsigned, AUDIT_BUFSIZ, 1+len-avail));
+		if (!avail)
+			goto out;
+		len = vsnprintf(skb_tail_pointer(skb), avail, fmt, args2);
+	}
+	va_end(args2);
+	if (len > 0)
+		skb_put(skb, len);
+out:
+	return;
+}
+
+/**
+ * audit_log_format - format a message into the audit buffer.
+ * @ab: audit_buffer
+ * @fmt: format string
+ * @...: optional parameters matching @fmt string
+ *
+ * All the work is done in audit_log_vformat.
+ */
+void audit_log_format(struct audit_buffer *ab, const char *fmt, ...)
+{
+	va_list args;
+
+	if (!ab)
+		return;
+	va_start(args, fmt);
+	audit_log_vformat(ab, fmt, args);
+	va_end(args);
+}
+
+/**
+ * audit_log_hex - convert a buffer to hex and append it to the audit skb
+ * @ab: the audit_buffer
+ * @buf: buffer to convert to hex
+ * @len: length of @buf to be converted
+ *
+ * No return value; failure to expand is silently ignored.
+ *
+ * This function will take the passed buf and convert it into a string of
+ * ascii hex digits. The new string is placed onto the skb.
+ */
+void audit_log_n_hex(struct audit_buffer *ab, const unsigned char *buf,
+		size_t len)
+{
+	int i, avail, new_len;
+	unsigned char *ptr;
+	struct sk_buff *skb;
+	static const unsigned char *hex = "0123456789ABCDEF";
+
+	if (!ab)
+		return;
+
+	BUG_ON(!ab->skb);
+	skb = ab->skb;
+	avail = skb_tailroom(skb);
+	new_len = len<<1;
+	if (new_len >= avail) {
+		/* Round the buffer request up to the next multiple */
+		new_len = AUDIT_BUFSIZ*(((new_len-avail)/AUDIT_BUFSIZ) + 1);
+		avail = audit_expand(ab, new_len);
+		if (!avail)
+			return;
+	}
+
+	ptr = skb_tail_pointer(skb);
+	for (i=0; i<len; i++) {
+		*ptr++ = hex[(buf[i] & 0xF0)>>4]; /* Upper nibble */
+		*ptr++ = hex[buf[i] & 0x0F];	  /* Lower nibble */
+	}
+	*ptr = 0;
+	skb_put(skb, len << 1); /* new string is twice the old string */
+}
+
+/*
+ * Format a string of no more than slen characters into the audit buffer,
+ * enclosed in quote marks.
+ */
+void audit_log_n_string(struct audit_buffer *ab, const char *string,
+			size_t slen)
+{
+	int avail, new_len;
+	unsigned char *ptr;
+	struct sk_buff *skb;
+
+	if (!ab)
+		return;
+
+	BUG_ON(!ab->skb);
+	skb = ab->skb;
+	avail = skb_tailroom(skb);
+	new_len = slen + 3;	/* enclosing quotes + null terminator */
+	if (new_len > avail) {
+		avail = audit_expand(ab, new_len);
+		if (!avail)
+			return;
+	}
+	ptr = skb_tail_pointer(skb);
+	*ptr++ = '"';
+	memcpy(ptr, string, slen);
+	ptr += slen;
+	*ptr++ = '"';
+	*ptr = 0;
+	skb_put(skb, slen + 2);	/* don't include null terminator */
+}
+
+/**
+ * audit_string_contains_control - does a string need to be logged in hex
+ * @string: string to be checked
+ * @len: max length of the string to check
+ */
+int audit_string_contains_control(const char *string, size_t len)
+{
+	const unsigned char *p;
+	for (p = string; p < (const unsigned char *)string + len && *p; p++) {
+		if (*p == '"' || *p < 0x21 || *p > 0x7e)
+			return 1;
+	}
+	return 0;
+}
+
+/**
+ * audit_log_n_untrustedstring - log a string that may contain random characters
+ * @ab: audit_buffer
+ * @len: length of string (not including trailing null)
+ * @string: string to be logged
+ *
+ * This code will escape a string that is passed to it if the string
+ * contains a control character, unprintable character, double quote mark,
+ * or a space. Unescaped strings will start and end with a double quote mark.
+ * Strings that are escaped are printed in hex (2 digits per char).
+ *
+ * The caller specifies the number of characters in the string to log, which may
+ * or may not be the entire string.
+ */
+void audit_log_n_untrustedstring(struct audit_buffer *ab, const char *string,
+				 size_t len)
+{
+	if (audit_string_contains_control(string, len))
+		audit_log_n_hex(ab, string, len);
+	else
+		audit_log_n_string(ab, string, len);
+}
+
+/**
+ * audit_log_untrustedstring - log a string that may contain random characters
+ * @ab: audit_buffer
+ * @string: string to be logged
+ *
+ * Same as audit_log_n_untrustedstring(), except that strlen is used to
+ * determine string length.
+ */
+void audit_log_untrustedstring(struct audit_buffer *ab, const char *string)
+{
+	audit_log_n_untrustedstring(ab, string, strlen(string));
+}
+
+/* This is a helper-function to print the escaped d_path */
+void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
+		      struct path *path)
+{
+	char *p, *pathname;
+
+	if (prefix)
+		audit_log_format(ab, " %s", prefix);
+
+	/* We will allow 11 spaces for ' (deleted)' to be appended */
+	pathname = kmalloc(PATH_MAX+11, ab->gfp_mask);
+	if (!pathname) {
+		audit_log_format(ab, "<no memory>");
+		return;
+	}
+	p = d_path(path, pathname, PATH_MAX+11);
+	if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */
+		/* FIXME: can we save some information here? */
+		audit_log_format(ab, "<too long>");
+	} else
+		audit_log_untrustedstring(ab, p);
+	kfree(pathname);
+}
+
+/**
+ * audit_log_end - end one audit record
+ * @ab: the audit_buffer
+ *
+ * The netlink_* functions cannot be called inside an irq context, so
+ * the audit buffer is placed on a queue and a tasklet is scheduled to
+ * remove them from the queue outside the irq context.  May be called in
+ * any context.
+ */
+void audit_log_end(struct audit_buffer *ab)
+{
+	if (!ab)
+		return;
+	if (!audit_rate_check()) {
+		audit_log_lost("rate limit exceeded");
+	} else {
+		struct nlmsghdr *nlh = nlmsg_hdr(ab->skb);
+		nlh->nlmsg_len = ab->skb->len - NLMSG_SPACE(0);
+
+		if (audit_pid) {
+			skb_queue_tail(&audit_skb_queue, ab->skb);
+			wake_up_interruptible(&kauditd_wait);
+		} else {
+			if (nlh->nlmsg_type != AUDIT_EOE) {
+				if (printk_ratelimit()) {
+					printk(KERN_NOTICE "type=%d %s\n",
+						nlh->nlmsg_type,
+						ab->skb->data + NLMSG_SPACE(0));
+				} else
+					audit_log_lost("printk limit exceeded\n");
+			}
+			audit_hold_skb(ab->skb);
+		}
+		ab->skb = NULL;
+	}
+	audit_buffer_free(ab);
+}
+
+/**
+ * audit_log - Log an audit record
+ * @ctx: audit context
+ * @gfp_mask: type of allocation
+ * @type: audit message type
+ * @fmt: format string to use
+ * @...: variable parameters matching the format string
+ *
+ * This is a convenience function that calls audit_log_start,
+ * audit_log_vformat, and audit_log_end.  It may be called
+ * in any context.
+ */
+void audit_log(struct audit_context *ctx, gfp_t gfp_mask, int type,
+	       const char *fmt, ...)
+{
+	struct audit_buffer *ab;
+	va_list args;
+
+	ab = audit_log_start(ctx, gfp_mask, type);
+	if (ab) {
+		va_start(args, fmt);
+		audit_log_vformat(ab, fmt, args);
+		va_end(args);
+		audit_log_end(ab);
+	}
+}
+
+EXPORT_SYMBOL(audit_log_start);
+EXPORT_SYMBOL(audit_log_end);
+EXPORT_SYMBOL(audit_log_format);
+EXPORT_SYMBOL(audit_log);