releases/2.6.33.13/can-add-missing-socket-check-in-can-raw-release.patch

From 10022a6c66e199d8f61d9044543f38785713cbbd Mon Sep 17 00:00:00 2001
From: Oliver Hartkopp <socketcan@hartkopp.net>
Date: Wed, 20 Apr 2011 01:57:15 +0000
Subject: can: add missing socket check in can/raw release

From: Oliver Hartkopp <socketcan@hartkopp.net>

commit 10022a6c66e199d8f61d9044543f38785713cbbd upstream.

v2: added space after 'if' according code style.

We can get here with a NULL socket argument passed from userspace,
so we need to handle it accordingly.

Thanks to Dave Jones pointing at this issue in net/can/bcm.c

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 net/can/raw.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/net/can/raw.c
+++ b/net/can/raw.c
@@ -280,7 +280,12 @@ static int raw_init(struct sock *sk)
 static int raw_release(struct socket *sock)
 {
 	struct sock *sk = sock->sk;
-	struct raw_sock *ro = raw_sk(sk);
+	struct raw_sock *ro;
+
+	if (!sk)
+		return 0;
+
+	ro = raw_sk(sk);
 
 	unregister_netdevice_notifier(&ro->notifier);