From patchwork Sat Feb 9 04:53:01 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Coly Li X-Patchwork-Id: 10804107 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A14A9922 for ; Sat, 9 Feb 2019 04:53:50 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3C9EF28751 for ; Sat, 9 Feb 2019 04:53:50 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 30ECA2DD52; Sat, 9 Feb 2019 04:53:50 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DC0A22DD34 for ; Sat, 9 Feb 2019 04:53:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726883AbfBIExt (ORCPT ); Fri, 8 Feb 2019 23:53:49 -0500 Received: from mx2.suse.de ([195.135.220.15]:57720 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726222AbfBIExt (ORCPT ); Fri, 8 Feb 2019 23:53:49 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id EFD4EAF6F; Sat, 9 Feb 2019 04:53:47 +0000 (UTC) From: Coly Li To: axboe@kernel.dk Cc: linux-bcache@vger.kernel.org, linux-block@vger.kernel.org, Coly Li Subject: [PATCH 09/19] bcache: fix input overflow to sequential_cutoff Date: Sat, 9 Feb 2019 12:53:01 +0800 Message-Id: <20190209045311.15677-10-colyli@suse.de> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20190209045311.15677-1-colyli@suse.de> References: <20190209045311.15677-1-colyli@suse.de> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP People may set sequential_cutoff of a cached device via sysfs file, but current code does not check input value overflow. E.g. if value 4294967295 (UINT_MAX) is written to file sequential_cutoff, its value is 4GB, but if 4294967296 (UINT_MAX + 1) is written into, its value will be 0. This is an unexpected behavior. This patch replaces d_strtoi_h() by sysfs_strtoul_clamp() to convert input string to unsigned integer value, and limit its range in [0, UINT_MAX]. Then the input overflow can be fixed. Signed-off-by: Coly Li --- drivers/md/bcache/sysfs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c index bedd3e68fd29..96b64893f2cb 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -314,7 +314,9 @@ STORE(__cached_dev) dc->io_disable = v ? 1 : 0; } - d_strtoi_h(sequential_cutoff); + sysfs_strtoul_clamp(sequential_cutoff, + dc->sequential_cutoff, + 0, UINT_MAX); d_strtoi_h(readahead); if (attr == &sysfs_clear_stats)