[ 092/143] net: unix: allow bind to fail on mutex lock

Willy Tarreau
2014-05-12T02:01:41Z

From: Sasha Levin <sasha.levin@oracle.com>

[ 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: Willy Tarreau <w@1wt.eu>
---
net/unix/af_unix.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index bb0b008..79c1dce 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -674,7 +674,9 @@ 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)
@@ -806,7 +808,9 @@ 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)
--
1.7.12.2.21.g234cd45.dirty