From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9A9E2C433E0 for ; Wed, 20 May 2020 14:28:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 844DB207D3 for ; Wed, 20 May 2020 14:28:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728591AbgETO2W (ORCPT ); Wed, 20 May 2020 10:28:22 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:32800 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726868AbgETOWX (ORCPT ); Wed, 20 May 2020 10:22:23 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1jbPbu-00035L-Vi; Wed, 20 May 2020 15:22:19 +0100 Received: from ben by deadeye with local (Exim 4.93) (envelope-from ) id 1jbPbu-007DP7-8F; Wed, 20 May 2020 15:22:18 +0100 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, Denis Kirjanov , "Eric Dumazet" , syzbot+c2f1558d49e25cc36e5e@syzkaller.appspotmail.com, "Herbert Xu" Date: Wed, 20 May 2020 15:13:44 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 16/99] crypto: af_alg - Use bh_lock_sock in sk_destruct In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.84-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Herbert Xu commit 37f96694cf73ba116993a9d2d99ad6a75fa7fdb0 upstream. As af_alg_release_parent may be called from BH context (most notably due to an async request that only completes after socket closure, or as reported here because of an RCU-delayed sk_destruct call), we must use bh_lock_sock instead of lock_sock. Reported-by: syzbot+c2f1558d49e25cc36e5e@syzkaller.appspotmail.com Reported-by: Eric Dumazet Fixes: c840ac6af3f8 ("crypto: af_alg - Disallow bind/setkey/...") Signed-off-by: Herbert Xu Signed-off-by: Ben Hutchings --- crypto/af_alg.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/crypto/af_alg.c +++ b/crypto/af_alg.c @@ -136,11 +136,13 @@ void af_alg_release_parent(struct sock * sk = ask->parent; ask = alg_sk(sk); - lock_sock(sk); + local_bh_disable(); + bh_lock_sock(sk); ask->nokey_refcnt -= nokey; if (!last) last = !--ask->refcnt; - release_sock(sk); + bh_unlock_sock(sk); + local_bh_enable(); if (last) sock_put(sk);