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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 E5331C433E2 for ; Mon, 18 May 2020 17:39:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C71262083E for ; Mon, 18 May 2020 17:39:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589823544; bh=96uFTrB1wUL2K5VRxCTmC0WiSXnmT6PY0ZcORRRnhfA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=c/5nWm603NYKywN3qCmXRRKZJsej5+ZqalHXCt8Ki7C+CRiKTXTJJI27eQ+WeISGU OYojB8a7HAd7j6E477b0R62FTV9viIqFl7F7wdIqWJi5BXk94uRVnu+Zz1MTsp5Bmp POZAK1l/wnpdrlMCAND+CO8sERrqhN8B42wzjib4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728690AbgERRjE (ORCPT ); Mon, 18 May 2020 13:39:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:33394 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728657AbgERRjC (ORCPT ); Mon, 18 May 2020 13:39:02 -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 D554020829; Mon, 18 May 2020 17:39:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589823541; bh=96uFTrB1wUL2K5VRxCTmC0WiSXnmT6PY0ZcORRRnhfA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=2Hnkk3XdYoT1aw9tr75odNeZB1cHO8bAaP588ePGw/fo4PcSOeBxliUGM1jm+tlL9 2GTEWHkCi+eTBsuIufhLEe3HnZCR6DE3y7JyRqw9DbtBKc97Zx0opfgJeT1kJ2FSa/ BK8wmOd8Zimth7QziFRg992zwAlENSKyWEcePArw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dmitry Vyukov , Jens Axboe , Ben Hutchings Subject: [PATCH 4.4 24/86] blktrace: fix unlocked access to init/start-stop/teardown Date: Mon, 18 May 2020 19:35:55 +0200 Message-Id: <20200518173455.336819399@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200518173450.254571947@linuxfoundation.org> References: <20200518173450.254571947@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jens Axboe commit 1f2cac107c591c24b60b115d6050adc213d10fc0 upstream. sg.c calls into the blktrace functions without holding the proper queue mutex for doing setup, start/stop, or teardown. Add internal unlocked variants, and export the ones that do the proper locking. Fixes: 6da127ad0918 ("blktrace: Add blktrace ioctls to SCSI generic devices") Tested-by: Dmitry Vyukov Signed-off-by: Jens Axboe Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman --- kernel/trace/blktrace.c | 58 +++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 48 insertions(+), 10 deletions(-) --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -323,7 +323,7 @@ static void blk_trace_cleanup(struct blk put_probe_ref(); } -int blk_trace_remove(struct request_queue *q) +static int __blk_trace_remove(struct request_queue *q) { struct blk_trace *bt; @@ -336,6 +336,17 @@ int blk_trace_remove(struct request_queu return 0; } + +int blk_trace_remove(struct request_queue *q) +{ + int ret; + + mutex_lock(&q->blk_trace_mutex); + ret = __blk_trace_remove(q); + mutex_unlock(&q->blk_trace_mutex); + + return ret; +} EXPORT_SYMBOL_GPL(blk_trace_remove); static ssize_t blk_dropped_read(struct file *filp, char __user *buffer, @@ -546,9 +557,8 @@ err: return ret; } -int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, - struct block_device *bdev, - char __user *arg) +static int __blk_trace_setup(struct request_queue *q, char *name, dev_t dev, + struct block_device *bdev, char __user *arg) { struct blk_user_trace_setup buts; int ret; @@ -567,6 +577,19 @@ int blk_trace_setup(struct request_queue } return 0; } + +int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, + struct block_device *bdev, + char __user *arg) +{ + int ret; + + mutex_lock(&q->blk_trace_mutex); + ret = __blk_trace_setup(q, name, dev, bdev, arg); + mutex_unlock(&q->blk_trace_mutex); + + return ret; +} EXPORT_SYMBOL_GPL(blk_trace_setup); #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) @@ -603,7 +626,7 @@ static int compat_blk_trace_setup(struct } #endif -int blk_trace_startstop(struct request_queue *q, int start) +static int __blk_trace_startstop(struct request_queue *q, int start) { int ret; struct blk_trace *bt = q->blk_trace; @@ -642,6 +665,17 @@ int blk_trace_startstop(struct request_q return ret; } + +int blk_trace_startstop(struct request_queue *q, int start) +{ + int ret; + + mutex_lock(&q->blk_trace_mutex); + ret = __blk_trace_startstop(q, start); + mutex_unlock(&q->blk_trace_mutex); + + return ret; +} EXPORT_SYMBOL_GPL(blk_trace_startstop); /* @@ -672,7 +706,7 @@ int blk_trace_ioctl(struct block_device switch (cmd) { case BLKTRACESETUP: bdevname(bdev, b); - ret = blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); + ret = __blk_trace_setup(q, b, bdev->bd_dev, bdev, arg); break; #if defined(CONFIG_COMPAT) && defined(CONFIG_X86_64) case BLKTRACESETUP32: @@ -683,10 +717,10 @@ int blk_trace_ioctl(struct block_device case BLKTRACESTART: start = 1; case BLKTRACESTOP: - ret = blk_trace_startstop(q, start); + ret = __blk_trace_startstop(q, start); break; case BLKTRACETEARDOWN: - ret = blk_trace_remove(q); + ret = __blk_trace_remove(q); break; default: ret = -ENOTTY; @@ -704,10 +738,14 @@ int blk_trace_ioctl(struct block_device **/ void blk_trace_shutdown(struct request_queue *q) { + mutex_lock(&q->blk_trace_mutex); + if (q->blk_trace) { - blk_trace_startstop(q, 0); - blk_trace_remove(q); + __blk_trace_startstop(q, 0); + __blk_trace_remove(q); } + + mutex_unlock(&q->blk_trace_mutex); } /*