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=unavailable 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 2F27FC10F00 for ; Wed, 27 Mar 2019 18:07:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ECFD9217F5 for ; Wed, 27 Mar 2019 18:07:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553710029; bh=Jw8eDUIkLSCnQ+qMp6q1tOK7drPUgkAwHackCAwhMJQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=yJJVYnaYLu+hrJcJ9fqjNNW+ZcWAFZ6S+szEupMhCvR55K1QSZaZ9svmN83PlI/zG i7epJK8VoScaAhsgcN7TnYiHgfcT9iajAnLa97X5BdOcffnU/E7HPjhWHDbG79Sz+1 zuhq/T1MK0Syqmia/SlyJ4OUAT/Z8hHt3bHPoBK8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388100AbfC0SHI (ORCPT ); Wed, 27 Mar 2019 14:07:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:48866 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732924AbfC0SHE (ORCPT ); Wed, 27 Mar 2019 14:07:04 -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 738EF2183F; Wed, 27 Mar 2019 18:07:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553710023; bh=Jw8eDUIkLSCnQ+qMp6q1tOK7drPUgkAwHackCAwhMJQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Y608N6ixKv6HgHoZQZkrFC7F+pjbKMU5BP/tAo32ke/e/kJ0e4heKTwARLMCO2xlu 7vxQ6HMADOYNcJHvfq87CM2i8L6ySrcPPAXPeb4/WR/Hk0yLXjDjvQEtxjgas7P8iy i/zsenvtEO1zA63CUo3uU2DFUauIoKlKOAU3BXk8= 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 5.0 160/262] bcache: fix input overflow to cache set sysfs file io_error_halflife Date: Wed, 27 Mar 2019 14:00:15 -0400 Message-Id: <20190327180158.10245-160-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190327180158.10245-1-sashal@kernel.org> References: <20190327180158.10245-1-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 557a8a3270a1..3b287f974fd9 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -778,8 +778,17 @@ 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