Re: net: nfc: BUG and panic in accept() on 3.5-rc2

[Eric Dumazet <eric.dumazet@gmail.com>]

On Mon, 2012-06-11 at 16:41 +0200, Samuel Ortiz wrote:
> Hi Sasha,
> 
> On Mon, Jun 11, 2012 at 04:00:41PM +0200, Sasha Levin wrote:
> > Hi all,
> > 
> > I've stumbled on the following while fuzzing with trinity inside a KVM tools guest, running on 3.5-rc2:
> > 
> Thanks for the report, it could be worth adding this one to
> bugzilla.kernel.org.
> 
> What's trinity ?
> Also, if this one is reproducible, would you mind sharing some details about
> how we could reproduce it ?

Well, bugfix should be trivial enough ;)

diff --git a/net/nfc/rawsock.c b/net/nfc/rawsock.c
index ec1134c..208416e 100644
--- a/net/nfc/rawsock.c
+++ b/net/nfc/rawsock.c
@@ -54,11 +54,12 @@ static int rawsock_release(struct socket *sock)
 {
 	struct sock *sk = sock->sk;
 
-	pr_debug("sock=%p\n", sock);
-
-	sock_orphan(sk);
-	sock_put(sk);
+	pr_debug("sock=%p sk=%p\n", sock, sk);
 
+	if (sk) {
+		sock_orphan(sk);
+		sock_put(sk);
+	}
 	return 0;
 }