af_unix: fix incorrect revert of 'lock_interruptible' in stream receive code

As reported by Sultan Qasim, commit 3822b5c ("af_unix: Revert
'lock_interruptible' in stream receive code") was accidently applied
at the wrong place in the backport that appeared in 3.10.95, it
affected unix_dgram_recvmsg() instead of unix_stream_recvmsg() due
to now similar code sections there. The dgram part needs to remain
but the stream part needs to be removed.

Reported-By: Sultan Qasim <sultanqasim@gmail.com>
Fixes: 3a57e78 (3.10.95)
Signed-off-by: Willy Tarreau <w@1wt.eu>

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index f934e7ba5eb833c45098c59cb8bb440d9f50b52d..0061d003752abf4b9281fb2fe99f149da45a3637 100644 (file)
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -1934,7 +1934,14 @@ static int unix_dgram_recvmsg(struct kiocb *iocb, struct socket *sock,
        if (flags&MSG_OOB)
                goto out;
 
-       mutex_lock(&u->readlock);
+       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;
+       }
 
        skip = sk_peek_offset(sk, flags);
 
@@ -2083,14 +2090,7 @@ static int unix_stream_recvmsg(struct kiocb *iocb, struct socket *sock,
                memset(&tmp_scm, 0, sizeof(tmp_scm));
        }
 
-       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);
 
        do {
                int chunk;