From patchwork Wed Nov 4 16:13:39 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 7551671 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 9D760BEEA4 for ; Wed, 4 Nov 2015 16:14:18 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id D40752061F for ; Wed, 4 Nov 2015 16:14:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E57372061B for ; Wed, 4 Nov 2015 16:14:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754214AbbKDQNo (ORCPT ); Wed, 4 Nov 2015 11:13:44 -0500 Received: from mx2.suse.de ([195.135.220.15]:33431 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751836AbbKDQNn (ORCPT ); Wed, 4 Nov 2015 11:13:43 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 0417DAAD1; Wed, 4 Nov 2015 16:13:24 +0000 (UTC) Received: by quack.suse.cz (Postfix, from userid 1000) id BD4D580F24; Wed, 4 Nov 2015 17:13:40 +0100 (CET) From: Jan Kara To: axboe@kernel.dk Cc: LKML , linux-fsdevel@vger.kernel.org, Christoph Hellwig , Jan Kara Subject: [PATCH] brd: Refuse improperly aligned discard requests Date: Wed, 4 Nov 2015 17:13:39 +0100 Message-Id: <1446653619-22880-1-git-send-email-jack@suse.com> X-Mailer: git-send-email 2.1.4 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Currently when improperly aligned discard request is submitted, we just silently discard more / less data which results in filesystem corruption in some cases. Refuse such misaligned requests. Signed-off-by: Jan Kara --- drivers/block/brd.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/block/brd.c b/drivers/block/brd.c index b9794aeeb878..4ef4cdf67ede 100644 --- a/drivers/block/brd.c +++ b/drivers/block/brd.c @@ -337,6 +337,9 @@ static void brd_make_request(struct request_queue *q, struct bio *bio) goto io_error; if (unlikely(bio->bi_rw & REQ_DISCARD)) { + if (sector & ((PAGE_SIZE >> SECTOR_SHIFT) - 1) || + bio->bi_iter.bi_size & PAGE_MASK) + goto io_error; discard_from_brd(brd, sector, bio->bi_iter.bi_size); goto out; }