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 74B02C43381 for ; Wed, 27 Mar 2019 18:24:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3D28C2087C for ; Wed, 27 Mar 2019 18:24:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553711082; bh=G29KAmivEVauUP9kmJQ62V5Z8ACbEWa485xV7vn5CXw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=qkOpr6cgK+7kDsVi9uU3Mp6II54bDs+kJWF57Dz/zaCVp+UirkTxWlbLaVUf57o2p a2oUGEPxUyPOXy2v9crtSUctsBfdEWTgJhtMtG4NH9K71KV2ciGAfwlsZEvkQo5u61 w2nv/mOzjXf3zqmaQ8QzKmkz43ZepVjU7VRBBECE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404033AbfC0SYk (ORCPT ); Wed, 27 Mar 2019 14:24:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:43502 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390452AbfC0SYf (ORCPT ); Wed, 27 Mar 2019 14:24:35 -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 11F1A2087C; Wed, 27 Mar 2019 18:24:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553711074; bh=G29KAmivEVauUP9kmJQ62V5Z8ACbEWa485xV7vn5CXw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nUqHV8eq49GX/PNDlZfwSFxorQt/mMqr0GhNlnxxLSYzBnm02jl+6OFgbae7X9yHG okvEyJPi0VKTRqQekXaJD/EXvxCKxr5nBHss5ien+/nHVFWorckUFFx5fduCGBTnRM RcgfGRflWYUG+xtfa2HS1lU/t0R4lbiLDstp1HVU= 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 4.4 39/63] bcache: fix input overflow to cache set sysfs file io_error_halflife Date: Wed, 27 Mar 2019 14:22:59 -0400 Message-Id: <20190327182323.18577-39-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190327182323.18577-1-sashal@kernel.org> References: <20190327182323.18577-1-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 5a5c1f1bd8a5..87daccbbc61b 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -645,8 +645,17 @@ STORE(__bch_cache_set) c->error_limit = strtoul_or_return(buf) << IO_ERROR_SHIFT; /* 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; + } sysfs_strtoul(journal_delay_ms, c->journal_delay_ms); sysfs_strtoul(verify, c->verify); -- 2.19.1