Linux-libre 4.4-gnupck-4.4-gnu

1 files changed, 49 insertions, 41 deletions

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 128b0982c..ef05cd940 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -438,9 +438,10 @@ static int unix_dgram_peer_wake_me(struct sock *sk, struct sock *other)
 	return 0;
 }
 
-static inline int unix_writable(struct sock *sk)
+static int unix_writable(const struct sock *sk)
 {
-	return (atomic_read(&sk->sk_wmem_alloc) << 2) <= sk->sk_sndbuf;
+	return sk->sk_state != TCP_LISTEN &&
+	       (atomic_read(&sk->sk_wmem_alloc) << 2) <= sk->sk_sndbuf;
 }
 
 static void unix_write_space(struct sock *sk)
@@ -952,32 +953,20 @@ fail:
 	return NULL;
 }
 
-static int unix_mknod(const char *sun_path, umode_t mode, struct path *res)
+static int unix_mknod(struct dentry *dentry, struct path *path, umode_t mode,
+		      struct path *res)
 {
-	struct dentry *dentry;
-	struct path path;
-	int err = 0;
-	/*
-	 * Get the parent directory, calculate the hash for last
-	 * component.
-	 */
-	dentry = kern_path_create(AT_FDCWD, sun_path, &path, 0);
-	err = PTR_ERR(dentry);
-	if (IS_ERR(dentry))
-		return err;
+	int err;
 
-	/*
-	 * All right, let's create it.
-	 */
-	err = security_path_mknod(&path, dentry, mode, 0);
+	err = security_path_mknod(path, dentry, mode, 0);
 	if (!err) {
-		err = vfs_mknod(d_inode(path.dentry), dentry, mode, 0);
+		err = vfs_mknod(d_inode(path->dentry), dentry, mode, 0);
 		if (!err) {
-			res->mnt = mntget(path.mnt);
+			res->mnt = mntget(path->mnt);
 			res->dentry = dget(dentry);
 		}
 	}
-	done_path_create(&path, dentry);
+
 	return err;
 }
 
@@ -988,10 +977,12 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 	struct unix_sock *u = unix_sk(sk);
 	struct sockaddr_un *sunaddr = (struct sockaddr_un *)uaddr;
 	char *sun_path = sunaddr->sun_path;
-	int err;
+	int err, name_err;
 	unsigned int hash;
 	struct unix_address *addr;
 	struct hlist_head *list;
+	struct path path;
+	struct dentry *dentry;
 
 	err = -EINVAL;
 	if (sunaddr->sun_family != AF_UNIX)
@@ -1007,14 +998,34 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 		goto out;
 	addr_len = err;
 
+	name_err = 0;
+	dentry = NULL;
+	if (sun_path[0]) {
+		/* Get the parent directory, calculate the hash for last
+		 * component.
+		 */
+		dentry = kern_path_create(AT_FDCWD, sun_path, &path, 0);
+
+		if (IS_ERR(dentry)) {
+			/* delay report until after 'already bound' check */
+			name_err = PTR_ERR(dentry);
+			dentry = NULL;
+		}
+	}
+
 	err = mutex_lock_interruptible(&u->readlock);
 	if (err)
-		goto out;
+		goto out_path;
 
 	err = -EINVAL;
 	if (u->addr)
 		goto out_up;
 
+	if (name_err) {
+		err = name_err == -EEXIST ? -EADDRINUSE : name_err;
+		goto out_up;
+	}
+
 	err = -ENOMEM;
 	addr = kmalloc(sizeof(*addr)+addr_len, GFP_KERNEL);
 	if (!addr)
@@ -1025,11 +1036,11 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 	addr->hash = hash ^ sk->sk_type;
 	atomic_set(&addr->refcnt, 1);
 
-	if (sun_path[0]) {
-		struct path path;
+	if (dentry) {
+		struct path u_path;
 		umode_t mode = S_IFSOCK |
 		       (SOCK_INODE(sock)->i_mode & ~current_umask());
-		err = unix_mknod(sun_path, mode, &path);
+		err = unix_mknod(dentry, &path, mode, &u_path);
 		if (err) {
 			if (err == -EEXIST)
 				err = -EADDRINUSE;
@@ -1037,9 +1048,9 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
 			goto out_up;
 		}
 		addr->hash = UNIX_HASH_SIZE;
-		hash = d_backing_inode(path.dentry)->i_ino & (UNIX_HASH_SIZE-1);
+		hash = d_backing_inode(dentry)->i_ino & (UNIX_HASH_SIZE - 1);
 		spin_lock(&unix_table_lock);
-		u->path = path;
+		u->path = u_path;
 		list = &unix_socket_table[hash];
 	} else {
 		spin_lock(&unix_table_lock);
@@ -1062,6 +1073,10 @@ out_unlock:
 	spin_unlock(&unix_table_lock);
 out_up:
 	mutex_unlock(&u->readlock);
+out_path:
+	if (dentry)
+		done_path_create(&path, dentry);
+
 out:
 	return err;
 }
@@ -2190,7 +2205,7 @@ static long unix_stream_data_wait(struct sock *sk, long timeo,
 		    !timeo)
 			break;
 
-		set_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+		sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
 		unix_state_unlock(sk);
 		timeo = freezable_schedule_timeout(timeo);
 		unix_state_lock(sk);
@@ -2198,7 +2213,7 @@ static long unix_stream_data_wait(struct sock *sk, long timeo,
 		if (sock_flag(sk, SOCK_DEAD))
 			break;
 
-		clear_bit(SOCK_ASYNC_WAITDATA, &sk->sk_socket->flags);
+		sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
 	}
 
 	finish_wait(sk_sleep(sk), &wait);
@@ -2255,14 +2270,7 @@ static int unix_stream_read_generic(struct unix_stream_read_state *state)
 	/* Lock the socket to prevent queue disordering
 	 * while sleeps in memcpy_tomsg
 	 */
-	err = mutex_lock_interruptible(&u->readlock);
-	if (unlikely(err)) {
-		/* recvmsg() in non blocking mode is supposed to return -EAGAIN
-		 * sk_rcvtimeo is not honored by mutex_lock_interruptible()
-		 */
-		err = noblock ? -EAGAIN : -ERESTARTSYS;
-		goto out;
-	}
+	mutex_lock(&u->readlock);
 
 	if (flags & MSG_PEEK)
 		skip = sk_peek_offset(sk, flags);
@@ -2306,12 +2314,12 @@ again:
 			timeo = unix_stream_data_wait(sk, timeo, last,
 						      last_len);
 
-			if (signal_pending(current) ||
-			    mutex_lock_interruptible(&u->readlock)) {
+			if (signal_pending(current)) {
 				err = sock_intr_errno(timeo);
 				goto out;
 			}
 
+			mutex_lock(&u->readlock);
 			continue;
 unlock:
 			unix_state_unlock(sk);
@@ -2682,7 +2690,7 @@ static unsigned int unix_dgram_poll(struct file *file, struct socket *sock,
 	if (writable)
 		mask |= POLLOUT | POLLWRNORM | POLLWRBAND;
 	else
-		set_bit(SOCK_ASYNC_NOSPACE, &sk->sk_socket->flags);
+		sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
 
 	return mask;
 }