Merge branch 'audit.b64' of git://git.kernel.org/pub/scm/linux/kernel…

…/git/viro/audit-current

* 'audit.b64' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
  audit mmap
  audit: make link()/linkat() match "attribute change" predicate
  audit: Use rcu for task lookup protection
  audit: Do not send uninitialized data for AUDIT_TTY_GET
  audit: Call tty_audit_push_task() outside preempt disabled
  in untag_chunk() we need to do alloc_chunk() a bit earlier
  audit: make functions static
  Audit: add support to match lsm labels on user audit messages

drivers/char/tty_audit.c

@@ -188,25 +188,43 @@ void tty_audit_tiocsti(struct tty_struct *tty, char ch)
 }
 
 /**
- *	tty_audit_push_task	-	Flush task's pending audit data
+ * tty_audit_push_task	-	Flush task's pending audit data
+ * @tsk:		task pointer
+ * @loginuid:		sender login uid
+ * @sessionid:		sender session id
+ *
+ * Called with a ref on @tsk held. Try to lock sighand and get a
+ * reference to the tty audit buffer if available.
+ * Flush the buffer or return an appropriate error code.
  */
-void tty_audit_push_task(struct task_struct *tsk, uid_t loginuid, u32 sessionid)
+int tty_audit_push_task(struct task_struct *tsk, uid_t loginuid, u32 sessionid)
 {
-	struct tty_audit_buf *buf;
+	struct tty_audit_buf *buf = ERR_PTR(-EPERM);
+	unsigned long flags;
 
-	spin_lock_irq(&tsk->sighand->siglock);
-	buf = tsk->signal->tty_audit_buf;
-	if (buf)
-		atomic_inc(&buf->count);
-	spin_unlock_irq(&tsk->sighand->siglock);
-	if (!buf)
-		return;
+	if (!lock_task_sighand(tsk, &flags))
+		return -ESRCH;
+
+	if (tsk->signal->audit_tty) {
+		buf = tsk->signal->tty_audit_buf;
+		if (buf)
+			atomic_inc(&buf->count);
+	}
+	unlock_task_sighand(tsk, &flags);
+
+	/*
+	 * Return 0 when signal->audit_tty set
+	 * but tsk->signal->tty_audit_buf == NULL.
+	 */
+	if (!buf || IS_ERR(buf))
+		return PTR_ERR(buf);
 
 	mutex_lock(&buf->mutex);
 	tty_audit_buf_push(tsk, loginuid, sessionid, buf);
 	mutex_unlock(&buf->mutex);
 
 	tty_audit_buf_put(buf);
+	return 0;
 }
 
 /**

include/asm-generic/audit_change_attr.h

@@ -20,3 +20,7 @@ __NR_chown32,
 __NR_fchown32,
 __NR_lchown32,
 #endif
+__NR_link,
+#ifdef __NR_linkat
+__NR_linkat,
+#endif

include/linux/audit.h

@@ -102,6 +102,7 @@
 #define AUDIT_EOE		1320	/* End of multi-record event */
 #define AUDIT_BPRM_FCAPS	1321	/* Information about fcaps increasing perms */
 #define AUDIT_CAPSET		1322	/* Record showing argument to sys_capset */
+#define AUDIT_MMAP		1323	/* Record showing descriptor and flags in mmap */
 
 #define AUDIT_AVC		1400	/* SE Linux avc denial or grant */
 #define AUDIT_SELINUX_ERR	1401	/* Internal SE Linux Errors */
@@ -478,6 +479,7 @@ extern int __audit_log_bprm_fcaps(struct linux_binprm *bprm,
 				  const struct cred *new,
 				  const struct cred *old);
 extern void __audit_log_capset(pid_t pid, const struct cred *new, const struct cred *old);
+extern void __audit_mmap_fd(int fd, int flags);
 
 static inline void audit_ipc_obj(struct kern_ipc_perm *ipcp)
 {
@@ -531,6 +533,12 @@ static inline void audit_log_capset(pid_t pid, const struct cred *new,
 		__audit_log_capset(pid, new, old);
 }
 
+static inline void audit_mmap_fd(int fd, int flags)
+{
+	if (unlikely(!audit_dummy_context()))
+		__audit_mmap_fd(fd, flags);
+}
+
 extern int audit_n_rules;
 extern int audit_signals;
 #else
@@ -564,6 +572,7 @@ extern int audit_signals;
 #define audit_mq_getsetattr(d,s) ((void)0)
 #define audit_log_bprm_fcaps(b, ncr, ocr) ({ 0; })
 #define audit_log_capset(pid, ncr, ocr) ((void)0)
+#define audit_mmap_fd(fd, flags) ((void)0)
 #define audit_ptrace(t) ((void)0)
 #define audit_n_rules 0
 #define audit_signals 0

include/linux/tty.h

@@ -541,8 +541,8 @@ extern void tty_audit_exit(void);
 extern void tty_audit_fork(struct signal_struct *sig);
 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
 extern void tty_audit_push(struct tty_struct *tty);
-extern void tty_audit_push_task(struct task_struct *tsk,
-					uid_t loginuid, u32 sessionid);
+extern int tty_audit_push_task(struct task_struct *tsk,
+			       uid_t loginuid, u32 sessionid);
 #else
 static inline void tty_audit_add_data(struct tty_struct *tty,
 				      unsigned char *data, size_t size)
@@ -560,9 +560,10 @@ static inline void tty_audit_fork(struct signal_struct *sig)
 static inline void tty_audit_push(struct tty_struct *tty)
 {
 }
-static inline void tty_audit_push_task(struct task_struct *tsk,
-					uid_t loginuid, u32 sessionid)
+static inline int tty_audit_push_task(struct task_struct *tsk,
+				      uid_t loginuid, u32 sessionid)
 {
+	return 0;
 }
 #endif
 

kernel/audit.c

@@ -467,23 +467,16 @@ static int audit_prepare_user_tty(pid_t pid, uid_t loginuid, u32 sessionid)
 	struct task_struct *tsk;
 	int err;
 
-	read_lock(&tasklist_lock);
+	rcu_read_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);
+	if (!tsk) {
+		rcu_read_unlock();
+		return -ESRCH;
+	}
+	get_task_struct(tsk);
+	rcu_read_unlock();
+	err = tty_audit_push_task(tsk, loginuid, sessionid);
+	put_task_struct(tsk);
 	return err;
 }
 
@@ -506,7 +499,7 @@ int audit_send_list(void *_dest)
 }
 
 struct sk_buff *audit_make_reply(int pid, int seq, int type, int done,
-				 int multi, void *payload, int size)
+				 int multi, const void *payload, int size)
 {
 	struct sk_buff	*skb;
 	struct nlmsghdr	*nlh;
@@ -555,8 +548,8 @@ static int audit_send_reply_thread(void *arg)
  * 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)
+static void audit_send_reply(int pid, int seq, int type, int done, int multi,
+			     const void *payload, int size)
 {
 	struct sk_buff *skb;
 	struct task_struct *tsk;
@@ -880,40 +873,40 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 	case AUDIT_TTY_GET: {
 		struct audit_tty_status s;
 		struct task_struct *tsk;
+		unsigned long flags;
 
-		read_lock(&tasklist_lock);
+		rcu_read_lock();
 		tsk = find_task_by_vpid(pid);
-		if (!tsk)
-			err = -ESRCH;
-		else {
-			spin_lock_irq(&tsk->sighand->siglock);
+		if (tsk && lock_task_sighand(tsk, &flags)) {
 			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));
+			unlock_task_sighand(tsk, &flags);
+		} else
+			err = -ESRCH;
+		rcu_read_unlock();
+
+		if (!err)
+			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;
+		unsigned long flags;
 
 		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);
+		rcu_read_lock();
 		tsk = find_task_by_vpid(pid);
-		if (!tsk)
-			err = -ESRCH;
-		else {
-			spin_lock_irq(&tsk->sighand->siglock);
+		if (tsk && lock_task_sighand(tsk, &flags)) {
 			tsk->signal->audit_tty = s->enabled != 0;
-			spin_unlock_irq(&tsk->sighand->siglock);
-		}
-		read_unlock(&tasklist_lock);
+			unlock_task_sighand(tsk, &flags);
+		} else
+			err = -ESRCH;
+		rcu_read_unlock();
 		break;
 	}
 	default:

kernel/audit.h

@@ -84,10 +84,7 @@ extern int audit_compare_dname_path(const char *dname, const char *path,
 				    int *dirlen);
 extern struct sk_buff *	    audit_make_reply(int pid, int seq, int type,
 					     int done, int multi,
-					     void *payload, int size);
-extern void		    audit_send_reply(int pid, int seq, int type,
-					     int done, int multi,
-					     void *payload, int size);
+					     const void *payload, int size);
 extern void		    audit_panic(const char *message);
 
 struct audit_netlink_list {

kernel/audit_tree.c

@@ -223,7 +223,7 @@ static void untag_chunk(struct node *p)
 {
 	struct audit_chunk *chunk = find_chunk(p);
 	struct fsnotify_mark *entry = &chunk->mark;
-	struct audit_chunk *new;
+	struct audit_chunk *new = NULL;
 	struct audit_tree *owner;
 	int size = chunk->count - 1;
 	int i, j;
@@ -232,9 +232,14 @@ static void untag_chunk(struct node *p)
 
 	spin_unlock(&hash_lock);
 
+	if (size)
+		new = alloc_chunk(size);
+
 	spin_lock(&entry->lock);
 	if (chunk->dead || !entry->i.inode) {
 		spin_unlock(&entry->lock);
+		if (new)
+			free_chunk(new);
 		goto out;
 	}
 
@@ -255,9 +260,9 @@ static void untag_chunk(struct node *p)
 		goto out;
 	}
 
-	new = alloc_chunk(size);
 	if (!new)
 		goto Fallback;
+
 	fsnotify_duplicate_mark(&new->mark, entry);
 	if (fsnotify_add_mark(&new->mark, new->mark.group, new->mark.i.inode, NULL, 1)) {
 		free_chunk(new);

kernel/audit_watch.c

@@ -60,7 +60,7 @@ struct audit_parent {
 };
 
 /* fsnotify handle. */
-struct fsnotify_group *audit_watch_group;
+static struct fsnotify_group *audit_watch_group;
 
 /* fsnotify events we care about. */
 #define AUDIT_FS_WATCH (FS_MOVE | FS_CREATE | FS_DELETE | FS_DELETE_SELF |\
@@ -123,7 +123,7 @@ void audit_put_watch(struct audit_watch *watch)
 	}
 }
 
-void audit_remove_watch(struct audit_watch *watch)
+static void audit_remove_watch(struct audit_watch *watch)
 {
 	list_del(&watch->wlist);
 	audit_put_parent(watch->parent);

kernel/auditfilter.c

@@ -1252,6 +1252,18 @@ static int audit_filter_user_rules(struct netlink_skb_parms *cb,
 		case AUDIT_LOGINUID:
 			result = audit_comparator(cb->loginuid, f->op, f->val);
 			break;
+		case AUDIT_SUBJ_USER:
+		case AUDIT_SUBJ_ROLE:
+		case AUDIT_SUBJ_TYPE:
+		case AUDIT_SUBJ_SEN:
+		case AUDIT_SUBJ_CLR:
+			if (f->lsm_rule)
+				result = security_audit_rule_match(cb->sid,
+								   f->type,
+								   f->op,
+								   f->lsm_rule,
+								   NULL);
+			break;
 		}
 
 		if (!result)

kernel/auditsc.c

@@ -241,6 +241,10 @@ struct audit_context {
 			pid_t			pid;
 			struct audit_cap_data	cap;
 		} capset;
+		struct {
+			int			fd;
+			int			flags;
+		} mmap;
 	};
 	int fds[2];
 
@@ -1305,6 +1309,10 @@ static void show_special(struct audit_context *context, int *call_panic)
 		audit_log_cap(ab, "cap_pp", &context->capset.cap.permitted);
 		audit_log_cap(ab, "cap_pe", &context->capset.cap.effective);
 		break; }
+	case AUDIT_MMAP: {
+		audit_log_format(ab, "fd=%d flags=0x%x", context->mmap.fd,
+				 context->mmap.flags);
+		break; }
 	}
 	audit_log_end(ab);
 }
@@ -2476,6 +2484,14 @@ void __audit_log_capset(pid_t pid,
 	context->type = AUDIT_CAPSET;
 }
 
+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;
+}
+
 /**
  * audit_core_dumps - record information about processes that end abnormally
  * @signr: signal value

mm/mmap.c

@@ -28,6 +28,7 @@
 #include <linux/rmap.h>
 #include <linux/mmu_notifier.h>
 #include <linux/perf_event.h>
+#include <linux/audit.h>
 
 #include <asm/uaccess.h>
 #include <asm/cacheflush.h>
@@ -1108,6 +1109,7 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
 	unsigned long retval = -EBADF;
 
 	if (!(flags & MAP_ANONYMOUS)) {
+		audit_mmap_fd(fd, flags);
 		if (unlikely(flags & MAP_HUGETLB))
 			return -EINVAL;
 		file = fget(fd);

mm/nommu.c

@@ -29,6 +29,7 @@
 #include <linux/personality.h>
 #include <linux/security.h>
 #include <linux/syscalls.h>
+#include <linux/audit.h>
 
 #include <asm/uaccess.h>
 #include <asm/tlb.h>
@@ -1458,6 +1459,7 @@ SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
 	struct file *file = NULL;
 	unsigned long retval = -EBADF;
 
+	audit_mmap_fd(fd, flags);
 	if (!(flags & MAP_ANONYMOUS)) {
 		file = fget(fd);
 		if (!file)