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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 80875C3A5A2 for ; Tue, 3 Sep 2019 13:04:29 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5527822D6D for ; Tue, 3 Sep 2019 13:04:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5527822D6D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:45844 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i58U0-0008W2-AH for qemu-devel@archiver.kernel.org; Tue, 03 Sep 2019 09:04:28 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:46644) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i58Sl-0007Vu-4G for qemu-devel@nongnu.org; Tue, 03 Sep 2019 09:03:12 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i58Si-0000Fm-Ma for qemu-devel@nongnu.org; Tue, 03 Sep 2019 09:03:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:56196) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i58Sa-0000D5-2w; Tue, 03 Sep 2019 09:03:00 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 190CF3083394; Tue, 3 Sep 2019 13:02:58 +0000 (UTC) Received: from localhost.localdomain (ovpn-116-195.ams2.redhat.com [10.36.116.195]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 810701000343; Tue, 3 Sep 2019 13:02:56 +0000 (UTC) Date: Tue, 3 Sep 2019 15:02:54 +0200 From: Kevin Wolf To: Peter Lieven Message-ID: <20190903130254.GG4582@localhost.localdomain> References: <20190902152413.14070-1-pl@kamp.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190902152413.14070-1-pl@kamp.de> User-Agent: Mutt/1.12.0 (2019-05-25) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.44]); Tue, 03 Sep 2019 13:02:58 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH V2] block/vhdx: add check for truncated image files X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: codyprime@gmail.com, mreitz@redhat.com, jhf@kamp.de, qemu-block@nongnu.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Am 02.09.2019 um 17:24 hat Peter Lieven geschrieben: > qemu is currently not able to detect truncated vhdx image files. > Add a basic check if all allocated blocks are reachable at open and > report all errors during bdrv_co_check. > > Signed-off-by: Peter Lieven > --- > V2: - add error reporting [Kevin] > - use bdrv_getlength instead of bdrv_get_allocated_file_size [Kevin] > - factor out BAT entry check and add error reporting for region > overlaps > - already check on vhdx_open > > block/vhdx.c | 85 +++++++++++++++++++++++++++++++++++++++++----------- > 1 file changed, 68 insertions(+), 17 deletions(-) > > diff --git a/block/vhdx.c b/block/vhdx.c > index 6a09d0a55c..6afba5e8c2 100644 > --- a/block/vhdx.c > +++ b/block/vhdx.c > @@ -24,6 +24,7 @@ > #include "qemu/option.h" > #include "qemu/crc32c.h" > #include "qemu/bswap.h" > +#include "qemu/error-report.h" > #include "vhdx.h" > #include "migration/blocker.h" > #include "qemu/uuid.h" > @@ -235,6 +236,9 @@ static int vhdx_region_check(BDRVVHDXState *s, uint64_t start, uint64_t length) > end = start + length; > QLIST_FOREACH(r, &s->regions, entries) { > if (!((start >= r->end) || (end <= r->start))) { > + error_report("VHDX region %" PRIu64 "-%" PRIu64 " overlaps with " > + "region %" PRIu64 "-%." PRIu64, start, end, r->start, > + r->end); > ret = -EINVAL; > goto exit; > } > @@ -877,6 +881,60 @@ static void vhdx_calc_bat_entries(BDRVVHDXState *s) > > } > > +static int vhdx_check_bat_entries(BlockDriverState *bs, int *errcnt) > +{ > + BDRVVHDXState *s = bs->opaque; > + int64_t image_file_size = bdrv_getlength(bs->file->bs); > + uint64_t payblocks = s->chunk_ratio; > + int i, ret = 0; bdrv_getlength() can fail. It's probably better to error out immediately instead of reporting that every BAT entry is > -1. > + for (i = 0; i < s->bat_entries; i++) { s->bat_entries is uint32_t, so i should probably be the same. > + if ((s->bat[i] & VHDX_BAT_STATE_BIT_MASK) == > + PAYLOAD_BLOCK_FULLY_PRESENT) { > + /* > + * Check if fully allocated BAT entries do not reside after > + * end of the image file. > + */ > + if ((s->bat[i] & VHDX_BAT_FILE_OFF_MASK) + s->block_size > > + image_file_size) { Didn't we want to introduce an overflow check before making this check? Something like if (bat_offset > UINT64_MAX - s->block_size)? > + error_report("VHDX BAT entry %d offset points after end of " > + "file. Image has probably been truncated.", i); > + ret = -EINVAL; > + if (!errcnt) { > + break; > + } > + (*errcnt)++; > + } > + > + /* > + * verify populated BAT field file offsets against > + * region table and log entries > + */ > + if (payblocks--) { > + /* payload bat entries */ > + int ret2; > + ret2 = vhdx_region_check(s, s->bat[i] & VHDX_BAT_FILE_OFF_MASK, > + s->block_size); > + if (ret2 < 0) { > + ret = -EINVAL; > + if (errcnt) { This one you already noticed yourself. > + break; > + } > + (*errcnt)++; > + } > + } else { > + payblocks = s->chunk_ratio; > + /* > + * Once differencing files are supported, verify sector bitmap > + * blocks here > + */ > + } > + } > + } > + > + return ret; > +} The rest looks good to me. Kevin