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=-5.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,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 539C1ECE563 for ; Mon, 17 Sep 2018 23:00:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 09C31214AB for ; Mon, 17 Sep 2018 23:00:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 09C31214AB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729908AbeIRE3c (ORCPT ); Tue, 18 Sep 2018 00:29:32 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:48000 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727559AbeIRE3c (ORCPT ); Tue, 18 Sep 2018 00:29:32 -0400 Received: from localhost (li1825-44.members.linode.com [172.104.248.44]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id A36A7C03; Mon, 17 Sep 2018 23:00:04 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot , Josef Bacik , Jens Axboe Subject: [PATCH 4.14 004/126] nbd: dont allow invalid blocksize settings Date: Tue, 18 Sep 2018 00:40:52 +0200 Message-Id: <20180917211703.886762195@linuxfoundation.org> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20180917211703.481236999@linuxfoundation.org> References: <20180917211703.481236999@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review 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 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jens Axboe commit bc811f05d77f47059c197a98b6ad242eb03999cb upstream. syzbot reports a divide-by-zero off the NBD_SET_BLKSIZE ioctl. We need proper validation of the input here. Not just if it's zero, but also if the value is a power-of-2 and in a valid range. Add that. Cc: stable@vger.kernel.org Reported-by: syzbot Reviewed-by: Josef Bacik Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- drivers/block/nbd.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -1228,6 +1228,9 @@ static int __nbd_ioctl(struct block_devi case NBD_SET_SOCK: return nbd_add_socket(nbd, arg, false); case NBD_SET_BLKSIZE: + if (!arg || !is_power_of_2(arg) || arg < 512 || + arg > PAGE_SIZE) + return -EINVAL; nbd_size_set(nbd, arg, div_s64(config->bytesize, arg)); return 0;