From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-617694-1519837691-2-677999367376703077 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.249, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='uk', MailFrom='org' X-Spam-charsets: plain='UTF-8' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: stable-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1519837690; b=PlE3QM/URCmRqte7CS31fWgypod0DauoJRKfRAQC0+y9spM unGzkEzYTpGXBnBxBYLQqJr12rVaOuOvFUhUebRiBJ4An1EGY3uZTLlJ2s/MxicG k//u+wD9z0ukFZ6PfxYOVWspgNG0zYNAfTCfEy35w2LPICGfk1AkWaAyTJ1g+vt3 drxugzdIrhFEVjYiuvsAH+gMYR7O+xuz7NwCRF384qj+K0IC8atI65r7eQIKKQom x2hgboH+GknhJCLPW92ncBwSgmwOV7IQ4GcgyYie2enP/cJvyk2MzccIk67e9XtR fdara+yWwhtPrBPR5D5pXh0w+pHIrcqZDj8ShxQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=content-type:content-transfer-encoding :mime-version:from:to:cc:date:message-id:subject:in-reply-to :sender:list-id; s=arctest; t=1519837690; bh=JyqsWcN1PQ6A4ZanHON xfCQKf7IRghs/aR2j6oMu238=; b=NLz9kQDvElpnHU1osgPUHPBJJIzPv7THbma YYevQ2fHFRbKRIstLQwdBS+MNtD5EyIjUbGloSLkp043p64mky2q1ZfUjGhLXBbT M/UbJZKRBTMVyhyA2ZWsTt6+FuOhEfPBK0udoCtWVWSzhli+AzzJ62xHo0N0NsqJ n6nf4yUZCvUT5xT7U+Jg/KAdVrTgb6JXp+LQhilkbkytsya6NKmhZ0rEjMWHeOCh atUwtc7+Omu6RmBfXFydOSqvq+Ex00PjWPnMyMFa90Xi/imK5e92HeoOl/5tkYRb cCXm2wLTLJ7BW8M8Nzq0eEDGhfRpESPfwa3RxtwuvqlerxowdVw== ARC-Authentication-Results: i=1; mx4.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=decadent.org.uk; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=decadent.org.uk header.result=pass header_is_org_domain=yes Authentication-Results: mx4.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=decadent.org.uk; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=stable-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=decadent.org.uk header.result=pass header_is_org_domain=yes Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932162AbeB1RHe (ORCPT ); Wed, 28 Feb 2018 12:07:34 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:34310 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933212AbeB1PuN (ORCPT ); Wed, 28 Feb 2018 10:50:13 -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, "Jens Axboe" Date: Wed, 28 Feb 2018 15:20:18 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 016/254] blktrace: fix trace mutex deadlock In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: stable-owner@vger.kernel.org X-Mailing-List: stable@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 3.16.55-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Jens Axboe commit 2967acbb257a6a9bf912f4778b727e00972eac9b upstream. A previous commit changed the locking around registration/cleanup, but direct callers of blk_trace_remove() were missed. This means that if we hit the error path in setup, we will deadlock on attempting to re-acquire the queue trace mutex. Fixes: 1f2cac107c59 ("blktrace: fix unlocked access to init/start-stop/teardown") Signed-off-by: Jens Axboe Signed-off-by: Ben Hutchings --- kernel/trace/blktrace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -562,7 +562,7 @@ static int __blk_trace_setup(struct requ return ret; if (copy_to_user(arg, &buts, sizeof(buts))) { - blk_trace_remove(q); + __blk_trace_remove(q); return -EFAULT; } return 0; @@ -608,7 +608,7 @@ static int compat_blk_trace_setup(struct return ret; if (copy_to_user(arg, &buts.name, ARRAY_SIZE(buts.name))) { - blk_trace_remove(q); + __blk_trace_remove(q); return -EFAULT; }