net: unix: allow bind to fail on mutex lock

[ Upstream commit 37ab4fa7844a044dc21fde45e2a0fc2f3c3b6490 ]

This is similar to the set_peek_off patch where calling bind while the
socket is stuck in unix_dgram_recvmsg() will block and cause a hung task
spew after a while.

This is also the last place that did a straightforward mutex_lock(), so
there shouldn't be any more of these patches.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 8519968..c0a81a5 100644 (file)
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -712,7 +712,9 @@ static int unix_autobind(struct socket *sock)
        int err;
        unsigned int retries = 0;
 
-       mutex_lock(&u->readlock);
+       err = mutex_lock_interruptible(&u->readlock);
+       if (err)
+               return err;
 
        err = 0;
        if (u->addr)
@@ -845,7 +847,9 @@ static int unix_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
                goto out;
        addr_len = err;
 
-       mutex_lock(&u->readlock);
+       err = mutex_lock_interruptible(&u->readlock);
+       if (err)
+               goto out;
 
        err = -EINVAL;
        if (u->addr)