Merge branch 'audit.b63' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current

* 'audit.b63' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
  Fix rule eviction order for AUDIT_DIR
  Audit: clean up all op= output to include string quoting
  Audit: move audit_get_nd completely into audit_watch
  audit: seperate audit inode watches into a subfile
  Audit: clean up audit_receive_skb
  Audit: cleanup netlink mesg handling
  Audit: unify the printk of an skb when auditd not around
  Audit: dereferencing krule as if it were an audit_watch
  Audit: better estimation of execve record length
  Audit: fix audit watch use after free

include/linux/audit.h

@@ -599,6 +599,8 @@ extern void		    audit_log_untrustedstring(struct audit_buffer *ab,
 extern void		    audit_log_d_path(struct audit_buffer *ab,
 					     const char *prefix,
 					     struct path *path);
+extern void		    audit_log_key(struct audit_buffer *ab,
+					  char *key);
 extern void		    audit_log_lost(const char *message);
 extern int		    audit_update_lsm_rules(void);
 
@@ -621,6 +623,7 @@ extern int audit_enabled;
 #define audit_log_n_untrustedstring(a,n,s) do { ; } while (0)
 #define audit_log_untrustedstring(a,s) do { ; } while (0)
 #define audit_log_d_path(b, p, d) do { ; } while (0)
+#define audit_log_key(b, k) do { ; } while (0)
 #define audit_enabled 0
 #endif
 #endif

kernel/Makefile

@@ -70,7 +70,7 @@ obj-$(CONFIG_RESOURCE_COUNTERS) += res_counter.o
 obj-$(CONFIG_STOP_MACHINE) += stop_machine.o
 obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o
 obj-$(CONFIG_AUDIT) += audit.o auditfilter.o
-obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
+obj-$(CONFIG_AUDITSYSCALL) += auditsc.o audit_watch.o
 obj-$(CONFIG_GCOV_KERNEL) += gcov/
 obj-$(CONFIG_AUDIT_TREE) += audit_tree.o
 obj-$(CONFIG_KPROBES) += kprobes.o

kernel/audit.c

@@ -115,9 +115,6 @@ 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];
 
@@ -136,7 +133,7 @@ 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);
+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
@@ -375,6 +372,25 @@ static void audit_hold_skb(struct sk_buff *skb)
 		kfree_skb(skb);
 }
 
+/*
+ * For one reason or another this nlh isn't getting delivered to the userspace
+ * audit daemon, just send it to printk.
+ */
+static void audit_printk_skb(struct sk_buff *skb)
+{
+	struct nlmsghdr *nlh = nlmsg_hdr(skb);
+	char *data = NLMSG_DATA(nlh);
+
+	if (nlh->nlmsg_type != AUDIT_EOE) {
+		if (printk_ratelimit())
+			printk(KERN_NOTICE "type=%d %s\n", nlh->nlmsg_type, data);
+		else
+			audit_log_lost("printk limit exceeded\n");
+	}
+
+	audit_hold_skb(skb);
+}
+
 static void kauditd_send_skb(struct sk_buff *skb)
 {
 	int err;
@@ -427,14 +443,8 @@ static int kauditd_thread(void *dummy)
 		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);
-			}
+				audit_printk_skb(skb);
 		} else {
 			DECLARE_WAITQUEUE(wait, current);
 			set_current_state(TASK_INTERRUPTIBLE);
@@ -495,42 +505,25 @@ int audit_send_list(void *_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);
+	skb = nlmsg_new(size, GFP_KERNEL);
 	if (!skb)
 		return NULL;
 
-	nlh		 = NLMSG_PUT(skb, pid, seq, t, size);
-	nlh->nlmsg_flags = flags;
+	nlh	= NLMSG_NEW(skb, pid, seq, t, size, flags);
 	data	= NLMSG_DATA(nlh);
 	memcpy(data, payload, size);
 	return skb;
 
-nlmsg_failure:			/* Used by NLMSG_PUT */
+nlmsg_failure:			/* Used by NLMSG_NEW */
 	if (skb)
 		kfree_skb(skb);
 	return NULL;
@@ -926,28 +919,29 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 }
 
 /*
- * 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.
+ * Get message from 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;
+	/*
+	 * len MUST be signed for NLMSG_NEXT to be able to dec it below 0
+	 * if the nlmsg_len was not aligned
+	 */
+	int len;
+	int err;
 
-	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))) {
+	len = skb->len;
+
+	while (NLMSG_OK(nlh, len)) {
+		err = audit_receive_msg(skb, nlh);
+		/* if err or if this message says it wants a response */
+		if (err || (nlh->nlmsg_flags & NLM_F_ACK))
 			netlink_ack(skb, nlh, err);
-		} else if (nlh->nlmsg_flags & NLM_F_ACK)
-			netlink_ack(skb, nlh, 0);
-		skb_pull(skb, rlen);
+
+		nlh = NLMSG_NEXT(nlh, len);
 	}
 }
 
@@ -959,13 +953,6 @@ static void audit_receive(struct sk_buff  *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)
 {
@@ -991,12 +978,6 @@ static int __init audit_init(void)
 
 	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]);
 
@@ -1070,18 +1051,20 @@ static struct audit_buffer * audit_buffer_alloc(struct audit_context *ctx,
 			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;
+
+	ab->skb = nlmsg_new(AUDIT_BUFSIZ, gfp_mask);
+	if (!ab->skb)
+		goto nlmsg_failure;
+
+	nlh = NLMSG_NEW(ab->skb, 0, 0, type, 0, 0);
+
 	return ab;
+
+nlmsg_failure:                  /* Used by NLMSG_NEW */
+	kfree_skb(ab->skb);
+	ab->skb = NULL;
 err:
 	audit_buffer_free(ab);
 	return NULL;
@@ -1452,6 +1435,15 @@ void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
 	kfree(pathname);
 }
 
+void audit_log_key(struct audit_buffer *ab, char *key)
+{
+	audit_log_format(ab, " key=");
+	if (key)
+		audit_log_untrustedstring(ab, key);
+	else
+		audit_log_format(ab, "(null)");
+}
+
 /**
  * audit_log_end - end one audit record
  * @ab: the audit_buffer
@@ -1475,15 +1467,7 @@ void audit_log_end(struct audit_buffer *ab)
 			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);
+			audit_printk_skb(ab->skb);
 		}
 		ab->skb = NULL;
 	}

kernel/audit.h

@@ -53,18 +53,7 @@ enum audit_state {
 };
 
 /* Rule lists */
-struct audit_parent;
-
-struct audit_watch {
-	atomic_t		count;	/* reference count */
-	char			*path;	/* insertion path */
-	dev_t			dev;	/* associated superblock device */
-	unsigned long		ino;	/* associated inode number */
-	struct audit_parent	*parent; /* associated parent */
-	struct list_head	wlist;	/* entry in parent->watches list */
-	struct list_head	rules;	/* associated rules */
-};
-
+struct audit_watch;
 struct audit_tree;
 struct audit_chunk;
 
@@ -108,19 +97,28 @@ struct audit_netlink_list {
 
 int audit_send_list(void *);
 
-struct inotify_watch;
-/* Inotify handle */
-extern struct inotify_handle *audit_ih;
-
-extern void audit_free_parent(struct inotify_watch *);
-extern void audit_handle_ievent(struct inotify_watch *, u32, u32, u32,
-				const char *, struct inode *);
 extern int selinux_audit_rule_update(void);
 
 extern struct mutex audit_filter_mutex;
 extern void audit_free_rule_rcu(struct rcu_head *);
 extern struct list_head audit_filter_list[];
 
+/* audit watch functions */
+extern unsigned long audit_watch_inode(struct audit_watch *watch);
+extern dev_t audit_watch_dev(struct audit_watch *watch);
+extern void audit_put_watch(struct audit_watch *watch);
+extern void audit_get_watch(struct audit_watch *watch);
+extern int audit_to_watch(struct audit_krule *krule, char *path, int len, u32 op);
+extern int audit_add_watch(struct audit_krule *krule);
+extern void audit_remove_watch(struct audit_watch *watch);
+extern void audit_remove_watch_rule(struct audit_krule *krule, struct list_head *list);
+extern void audit_inotify_unregister(struct list_head *in_list);
+extern char *audit_watch_path(struct audit_watch *watch);
+extern struct list_head *audit_watch_rules(struct audit_watch *watch);
+
+extern struct audit_entry *audit_dupe_rule(struct audit_krule *old,
+					   struct audit_watch *watch);
+
 #ifdef CONFIG_AUDIT_TREE
 extern struct audit_chunk *audit_tree_lookup(const struct inode *);
 extern void audit_put_chunk(struct audit_chunk *);
@@ -130,10 +128,9 @@ extern int audit_add_tree_rule(struct audit_krule *);
 extern int audit_remove_tree_rule(struct audit_krule *);
 extern void audit_trim_trees(void);
 extern int audit_tag_tree(char *old, char *new);
-extern void audit_schedule_prune(void);
-extern void audit_prune_trees(void);
 extern const char *audit_tree_path(struct audit_tree *);
 extern void audit_put_tree(struct audit_tree *);
+extern void audit_kill_trees(struct list_head *);
 #else
 #define audit_remove_tree_rule(rule) BUG()
 #define audit_add_tree_rule(rule) -EINVAL
@@ -142,6 +139,7 @@ extern void audit_put_tree(struct audit_tree *);
 #define audit_put_tree(tree) (void)0
 #define audit_tag_tree(old, new) -EINVAL
 #define audit_tree_path(rule) ""	/* never called */
+#define audit_kill_trees(list) BUG()
 #endif
 
 extern char *audit_unpack_string(void **, size_t *, size_t);
@@ -160,7 +158,10 @@ static inline int audit_signal_info(int sig, struct task_struct *t)
 	return 0;
 }
 extern void audit_filter_inodes(struct task_struct *, struct audit_context *);
+extern struct list_head *audit_killed_trees(void);
 #else
 #define audit_signal_info(s,t) AUDIT_DISABLED
 #define audit_filter_inodes(t,c) AUDIT_DISABLED
 #endif
+
+extern struct mutex audit_cmd_mutex;

kernel/audit_tree.c

@@ -2,6 +2,7 @@
 #include <linux/inotify.h>
 #include <linux/namei.h>
 #include <linux/mount.h>
+#include <linux/kthread.h>
 
 struct audit_tree;
 struct audit_chunk;
@@ -441,13 +442,11 @@ static void kill_rules(struct audit_tree *tree)
 		if (rule->tree) {
 			/* not a half-baked one */
 			ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
-			audit_log_format(ab, "op=remove rule dir=");
+			audit_log_format(ab, "op=");
+			audit_log_string(ab, "remove rule");
+			audit_log_format(ab, " dir=");
 			audit_log_untrustedstring(ab, rule->tree->pathname);
-			if (rule->filterkey) {
-				audit_log_format(ab, " key=");
-				audit_log_untrustedstring(ab, rule->filterkey);
-			} else
-				audit_log_format(ab, " key=(null)");
+			audit_log_key(ab, rule->filterkey);
 			audit_log_format(ab, " list=%d res=1", rule->listnr);
 			audit_log_end(ab);
 			rule->tree = NULL;
@@ -519,6 +518,8 @@ static void trim_marked(struct audit_tree *tree)
 	}
 }
 
+static void audit_schedule_prune(void);
+
 /* called with audit_filter_mutex */
 int audit_remove_tree_rule(struct audit_krule *rule)
 {
@@ -824,10 +825,11 @@ int audit_tag_tree(char *old, char *new)
 
 /*
  * That gets run when evict_chunk() ends up needing to kill audit_tree.
- * Runs from a separate thread, with audit_cmd_mutex held.
+ * Runs from a separate thread.
  */
-void audit_prune_trees(void)
+static int prune_tree_thread(void *unused)
 {
+	mutex_lock(&audit_cmd_mutex);
 	mutex_lock(&audit_filter_mutex);
 
 	while (!list_empty(&prune_list)) {
@@ -844,6 +846,40 @@ void audit_prune_trees(void)
 	}
 
 	mutex_unlock(&audit_filter_mutex);
+	mutex_unlock(&audit_cmd_mutex);
+	return 0;
+}
+
+static void audit_schedule_prune(void)
+{
+	kthread_run(prune_tree_thread, NULL, "audit_prune_tree");
+}
+
+/*
+ * ... and that one is done if evict_chunk() decides to delay until the end
+ * of syscall.  Runs synchronously.
+ */
+void audit_kill_trees(struct list_head *list)
+{
+	mutex_lock(&audit_cmd_mutex);
+	mutex_lock(&audit_filter_mutex);
+
+	while (!list_empty(list)) {
+		struct audit_tree *victim;
+
+		victim = list_entry(list->next, struct audit_tree, list);
+		kill_rules(victim);
+		list_del_init(&victim->list);
+
+		mutex_unlock(&audit_filter_mutex);
+
+		prune_one(victim);
+
+		mutex_lock(&audit_filter_mutex);
+	}
+
+	mutex_unlock(&audit_filter_mutex);
+	mutex_unlock(&audit_cmd_mutex);
 }
 
 /*
@@ -854,6 +890,8 @@ void audit_prune_trees(void)
 static void evict_chunk(struct audit_chunk *chunk)
 {
 	struct audit_tree *owner;
+	struct list_head *postponed = audit_killed_trees();
+	int need_prune = 0;
 	int n;
 
 	if (chunk->dead)
@@ -869,15 +907,21 @@ static void evict_chunk(struct audit_chunk *chunk)
 		owner->root = NULL;
 		list_del_init(&owner->same_root);
 		spin_unlock(&hash_lock);
+		if (!postponed) {
 			kill_rules(owner);
 			list_move(&owner->list, &prune_list);
-		audit_schedule_prune();
+			need_prune = 1;
+		} else {
+			list_move(&owner->list, postponed);
+		}
 		spin_lock(&hash_lock);
 	}
 	list_del_rcu(&chunk->hash);
 	for (n = 0; n < chunk->count; n++)
 		list_del_init(&chunk->owners[n].list);
 	spin_unlock(&hash_lock);
+	if (need_prune)
+		audit_schedule_prune();
 	mutex_unlock(&audit_filter_mutex);
 }
 

kernel/auditsc.c

@@ -199,6 +199,7 @@ struct audit_context {
 
 	struct audit_tree_refs *trees, *first_trees;
 	int tree_count;
+	struct list_head killed_trees;
 
 	int type;
 	union {
@@ -548,9 +549,9 @@ static int audit_filter_rules(struct task_struct *tsk,
 			}
 			break;
 		case AUDIT_WATCH:
-			if (name && rule->watch->ino != (unsigned long)-1)
-				result = (name->dev == rule->watch->dev &&
-					  name->ino == rule->watch->ino);
+			if (name && audit_watch_inode(rule->watch) != (unsigned long)-1)
+				result = (name->dev == audit_watch_dev(rule->watch) &&
+					  name->ino == audit_watch_inode(rule->watch));
 			break;
 		case AUDIT_DIR:
 			if (ctx)
@@ -853,6 +854,7 @@ static inline struct audit_context *audit_alloc_context(enum audit_state state)
 	if (!(context = kmalloc(sizeof(*context), GFP_KERNEL)))
 		return NULL;
 	audit_zero_context(context, state);
+	INIT_LIST_HEAD(&context->killed_trees);
 	return context;
 }
 
@@ -1024,8 +1026,8 @@ static int audit_log_single_execve_arg(struct audit_context *context,
 {
 	char arg_num_len_buf[12];
 	const char __user *tmp_p = p;
-	/* how many digits are in arg_num? 3 is the length of " a=" */
-	size_t arg_num_len = snprintf(arg_num_len_buf, 12, "%d", arg_num) + 3;
+	/* 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;
 	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;
@@ -1137,7 +1139,7 @@ static int audit_log_single_execve_arg(struct audit_context *context,
 		if (has_cntl)
 			audit_log_n_hex(*ab, buf, to_send);
 		else
-			audit_log_format(*ab, "\"%s\"", buf);
+			audit_log_string(*ab, buf);
 
 		p += to_send;
 		len_left -= to_send;
@@ -1372,11 +1374,7 @@ static void audit_log_exit(struct audit_context *context, struct task_struct *ts
 
 
 	audit_log_task_info(ab, tsk);
-	if (context->filterkey) {
-		audit_log_format(ab, " key=");
-		audit_log_untrustedstring(ab, context->filterkey);
-	} else
-		audit_log_format(ab, " key=(null)");
+	audit_log_key(ab, context->filterkey);
 	audit_log_end(ab);
 
 	for (aux = context->aux; aux; aux = aux->next) {
@@ -1549,6 +1547,8 @@ void audit_free(struct task_struct *tsk)
 	/* that can happen only if we are called from do_exit() */
 	if (context->in_syscall && context->current_state == AUDIT_RECORD_CONTEXT)
 		audit_log_exit(context, tsk);
+	if (!list_empty(&context->killed_trees))
+		audit_kill_trees(&context->killed_trees);
 
 	audit_free_context(context);
 }
@@ -1692,6 +1692,9 @@ void audit_syscall_exit(int valid, long return_code)
 	context->in_syscall = 0;
 	context->prio = context->state == AUDIT_RECORD_CONTEXT ? ~0ULL : 0;
 
+	if (!list_empty(&context->killed_trees))
+		audit_kill_trees(&context->killed_trees);
+
 	if (context->previous) {
 		struct audit_context *new_context = context->previous;
 		context->previous  = NULL;
@@ -2525,3 +2528,11 @@ void audit_core_dumps(long signr)
 	audit_log_format(ab, " sig=%ld", signr);
 	audit_log_end(ab);
 }
+
+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;
+}