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=-9.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS, URIBL_BLOCKED,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 4DB6DC10F00 for ; Wed, 27 Mar 2019 19:02:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 143F52147C for ; Wed, 27 Mar 2019 19:02:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553713347; bh=Ploxc1biDKwP7+i00SXMoBOD9zQGhLey4ADF66l09/s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=gKJN6+fTpoOXC8j/GFKL9GYPRSFvkkAVldDkGHmDoTHkV+8xtxo297VkKjk3Q5pGI G8QW15FH0MK3ZMVSxfSKe7G66+t+yxKEL50Ft3yzBbJutu401MAT3bLUmoFnEe7hLS R+X0x0x2F+q3D4NDZbENrOBygEevPMhsytPguaxA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389504AbfC0SNt (ORCPT ); Wed, 27 Mar 2019 14:13:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:56562 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388621AbfC0SNr (ORCPT ); Wed, 27 Mar 2019 14:13:47 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2EED521855; Wed, 27 Mar 2019 18:13:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553710426; bh=Ploxc1biDKwP7+i00SXMoBOD9zQGhLey4ADF66l09/s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zGwslskrWvAHhNC3LOvtNQ1ao2ku5ZCXVC7/8hl2ZWZJSamtsQKoxAqRtBOaOSBmy 127K1XBOloMdOcCn5f+6eBKkSDS2v+udhv8IRe5vLKITjoaxqASYiT9bTuz/XctS1l YAbVWRpQ5PYgy/mrhUa+0SQJSHRcsg6at5fV9F+o= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Coly Li , Jens Axboe , Sasha Levin , linux-bcache@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 113/192] bcache: fix input overflow to cache set sysfs file io_error_halflife Date: Wed, 27 Mar 2019 14:09:05 -0400 Message-Id: <20190327181025.13507-113-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190327181025.13507-1-sashal@kernel.org> References: <20190327181025.13507-1-sashal@kernel.org> MIME-Version: 1.0 X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Coly Li [ Upstream commit a91fbda49f746119828f7e8ad0f0aa2ab0578f65 ] Cache set sysfs entry io_error_halflife is used to set c->error_decay. c->error_decay is in type unsigned int, and it is converted by strtoul_or_return(), therefore overflow to c->error_decay is possible for a large input value. This patch fixes the overflow by using strtoul_safe_clamp() to convert input string to an unsigned long value in range [0, UINT_MAX], then divides by 88 and set it to c->error_decay. Signed-off-by: Coly Li Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- drivers/md/bcache/sysfs.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c index 26f035a0c5b9..59bf13faf752 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -766,8 +766,17 @@ STORE(__bch_cache_set) c->error_limit = strtoul_or_return(buf); /* See count_io_errors() for why 88 */ - if (attr == &sysfs_io_error_halflife) - c->error_decay = strtoul_or_return(buf) / 88; + if (attr == &sysfs_io_error_halflife) { + unsigned long v = 0; + ssize_t ret; + + ret = strtoul_safe_clamp(buf, v, 0, UINT_MAX); + if (!ret) { + c->error_decay = v / 88; + return size; + } + return ret; + } if (attr == &sysfs_io_disable) { v = strtoul_or_return(buf); -- 2.19.1