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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 873A4C433E1 for ; Mon, 18 May 2020 17:44:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 60C1620715 for ; Mon, 18 May 2020 17:44:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589823874; bh=Lv0WdQHZZpH0+zsvuw1nREwCuf/qpR482iS0MwMpNcg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=QXwclPRBUgtpz3Qxc0vPAkXNT1IVnr2FftFHoWAQq17lB8i0cYlfVTwvmrQUxtyBU hd3weMFG1hsSJWjuR/1Jq88o6a0ztWfuR4OU1k0KxkEoL27tyWjiCGwbAzksNGoQEH z1xgqmrzTmTgYRygoDgJjKE0XfIIiUnqKfgRl5qk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729762AbgERRob (ORCPT ); Mon, 18 May 2020 13:44:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:42780 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729751AbgERRo2 (ORCPT ); Mon, 18 May 2020 13:44:28 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 7EE2B20715; Mon, 18 May 2020 17:44:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589823868; bh=Lv0WdQHZZpH0+zsvuw1nREwCuf/qpR482iS0MwMpNcg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gCpy/SWl16bPPEUKkub38EPH4hru1CySi2yKEk5XmpZruo/HkDNncqYl4yQhiSfQB NAT0arNKzikww/0c5IZ/pR2EAQROVwsvdxCsmOHv5ik2QCgYAVtBaU291y2pzjsjIr WRoWFMvkQlPajH1Z+6GX0IuxWSuYfFs09yRVk3rI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jens Axboe , Ben Hutchings , Sasha Levin Subject: [PATCH 4.9 31/90] blktrace: fix trace mutex deadlock Date: Mon, 18 May 2020 19:36:09 +0200 Message-Id: <20200518173457.510063696@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200518173450.930655662@linuxfoundation.org> References: <20200518173450.930655662@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 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 Signed-off-by: Sasha Levin --- kernel/trace/blktrace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 55337d797deb1..a88e677c74f31 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -572,7 +572,7 @@ static int __blk_trace_setup(struct request_queue *q, char *name, dev_t dev, return ret; if (copy_to_user(arg, &buts, sizeof(buts))) { - blk_trace_remove(q); + __blk_trace_remove(q); return -EFAULT; } return 0; @@ -618,7 +618,7 @@ static int compat_blk_trace_setup(struct request_queue *q, char *name, return ret; if (copy_to_user(arg, &buts.name, ARRAY_SIZE(buts.name))) { - blk_trace_remove(q); + __blk_trace_remove(q); return -EFAULT; } -- 2.20.1