appletalk: Fix OOPS in atalk_release().

Commit 60d9f461a20ba59219fdcdc30cbf8e3a4ad3f625 ("appletalk: remove
the BKL") added a dereference of "sk" before checking for NULL in
atalk_release().

Guard the code block completely, rather than partially, with the
NULL check.

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 5 deletions

diff --git a/net/appletalk/ddp.c b/net/appletalk/ddp.c
index 206e771e82d1..956a5302002a 100644
--- a/net/appletalk/ddp.c
+++ b/net/appletalk/ddp.c
@@ -1051,16 +1051,17 @@ static int atalk_release(struct socket *sock)
 {
         struct sock *sk = sock->sk;
 
-        sock_hold(sk);
-        lock_sock(sk);
         if (sk) {
+                sock_hold(sk);
+                lock_sock(sk);
+
                 sock_orphan(sk);
                 sock->sk = NULL;
                 atalk_destroy_socket(sk);
-        }
-        release_sock(sk);
-        sock_put(sk);
 
+                release_sock(sk);
+                sock_put(sk);
+        }
         return 0;
 }