From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752728AbbKOCGS (ORCPT ); Sat, 14 Nov 2015 21:06:18 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:35205 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752192AbbKOCEu (ORCPT ); Sat, 14 Nov 2015 21:04:50 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "David S. Miller" , "Guillaume Nault" Date: Sun, 15 Nov 2015 01:45:45 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 42/60] ppp: fix pppoe_dev deletion condition in pppoe_release() In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.247 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.73-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Guillaume Nault commit 1acea4f6ce1b1c0941438aca75dd2e5c6b09db60 upstream. We can't rely on PPPOX_ZOMBIE to decide whether to clear po->pppoe_dev. PPPOX_ZOMBIE can be set by pppoe_disc_rcv() even when po->pppoe_dev is NULL. So we have no guarantee that (sk->sk_state & PPPOX_ZOMBIE) implies (po->pppoe_dev != NULL). Since we're releasing a PPPoE socket, we want to release the pppoe_dev if it exists and reset sk_state to PPPOX_DEAD, no matter the previous value of sk_state. So we can just check for po->pppoe_dev and avoid any assumption on sk->sk_state. Fixes: 2b018d57ff18 ("pppoe: drop PPPOX_ZOMBIEs in pppoe_release") Signed-off-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- drivers/net/ppp/pppoe.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/net/ppp/pppoe.c +++ b/drivers/net/ppp/pppoe.c @@ -575,7 +575,7 @@ static int pppoe_release(struct socket * po = pppox_sk(sk); - if (sk->sk_state & (PPPOX_CONNECTED | PPPOX_BOUND | PPPOX_ZOMBIE)) { + if (po->pppoe_dev) { dev_put(po->pppoe_dev); po->pppoe_dev = NULL; }