From nobody Sat Apr 20 15:45:31 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org ARC-Seal: i=1; a=rsa-sha256; t=1568129244; cv=none; d=zoho.com; s=zohoarc; b=IxCaFhbyDDuTWaWdgmmrysmg0p3sgssLIdvkWX+l5yrEWI0NNgPi0MiqqHTPCRXvRtuO873zy9Mdj4z+YVn1fi1TSHjwN7XxKrU00GFBpPCYLaF0t+h+y2tT3U0Ym9PYTNF4pTj9DmJINBexzf2YjK/lp5LrnC+LBZx8+PIMzPM= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1568129244; h=Cc:Date:From:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:Message-ID:Sender:Subject:To:ARC-Authentication-Results; bh=DF0j7nt1UXitfG6e1xNYJcQVX6kIYSGNq5+anqsURUE=; b=HiuTHZ9hw0ml/Ta2xLkjoClzyWuZFlmQAkmVw4R0gBjZOzIhwkZi9vXzcdjajRIqZ6sB3YpHrWoZSp2hYTvYz+sn98xJ664PvitRnKOk18ufQ5IMRLS3vmp4wbg9nyQVXU7wcvHGZ6+elRx65rvZVLST4s36uCW2D4SVbrnIrS4= ARC-Authentication-Results: i=1; mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1568129244115583.7914594164534; Tue, 10 Sep 2019 08:27:24 -0700 (PDT) Received: from localhost ([::1]:41408 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i7i39-00046e-0y for importer@patchew.org; Tue, 10 Sep 2019 11:27:23 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:33699) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i7i2K-0003Tw-WD for qemu-devel@nongnu.org; Tue, 10 Sep 2019 11:26:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i7i2I-0004kV-Py for qemu-devel@nongnu.org; Tue, 10 Sep 2019 11:26:32 -0400 Received: from kerio.kamp.de ([195.62.97.192]:60250) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i7i2I-0004jU-Fx for qemu-devel@nongnu.org; Tue, 10 Sep 2019 11:26:30 -0400 Received: from submission.kamp.de ([195.62.97.28]) by kerio.kamp.de with ESMTPS (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256 bits)) for qemu-devel@nongnu.org; Tue, 10 Sep 2019 17:26:23 +0200 Received: (qmail 5618 invoked from network); 10 Sep 2019 15:26:25 -0000 Received: from lieven-pc.kamp-intra.net (HELO lieven-pc) (relay@kamp.de@::ffff:172.21.12.60) by submission.kamp.de with ESMTPS (DHE-RSA-AES256-GCM-SHA384 encrypted) ESMTPA; 10 Sep 2019 15:26:25 -0000 Received: by lieven-pc (Postfix, from userid 1060) id CCE0313D876; Tue, 10 Sep 2019 17:26:25 +0200 (CEST) X-Footer: a2FtcC5kZQ== From: Peter Lieven To: qemu-block@nongnu.org Date: Tue, 10 Sep 2019 17:26:22 +0200 Message-Id: <20190910152622.5432-1-pl@kamp.de> X-Mailer: git-send-email 2.17.1 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 195.62.97.192 Subject: [Qemu-devel] [PATCH V4] 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: kwolf@redhat.com, codyprime@gmail.com, Peter Lieven , qemu-devel@nongnu.org, mreitz@redhat.com, jhf@kamp.de Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" 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 --- V4: - allow partial last blocks [Kevin] - report offsets in error messages [Kevin] - check for start and end offset after eof V3: - check for bdrv_getlength failure [Kevin] - use uint32_t for i [Kevin] - check for BAT entry overflow [Kevin] - break on !errcnt in second check 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 | 120 +++++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 103 insertions(+), 17 deletions(-) diff --git a/block/vhdx.c b/block/vhdx.c index 6a09d0a55c..371f226286 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 =3D start + length; QLIST_FOREACH(r, &s->regions, entries) { if (!((start >=3D r->end) || (end <=3D r->start))) { + error_report("VHDX region %" PRIu64 "-%" PRIu64 " overlaps wit= h " + "region %" PRIu64 "-%." PRIu64, start, end, r->st= art, + r->end); ret =3D -EINVAL; goto exit; } @@ -877,6 +881,95 @@ static void vhdx_calc_bat_entries(BDRVVHDXState *s) =20 } =20 +static int vhdx_check_bat_entries(BlockDriverState *bs, int *errcnt) +{ + BDRVVHDXState *s =3D bs->opaque; + int64_t image_file_size =3D bdrv_getlength(bs->file->bs); + uint64_t payblocks =3D s->chunk_ratio; + uint64_t i; + int ret =3D 0; + + if (image_file_size < 0) { + error_report("Could not determinate VHDX image file size."); + return image_file_size; + } + + for (i =3D 0; i < s->bat_entries; i++) { + if ((s->bat[i] & VHDX_BAT_STATE_BIT_MASK) =3D=3D + PAYLOAD_BLOCK_FULLY_PRESENT) { + uint64_t offset =3D s->bat[i] & VHDX_BAT_FILE_OFF_MASK; + /* + * Allow that the last block exists only partially. The VHDX s= pec + * states that the image file can only grow in blocksize incre= ments, + * but QEMU created images with partial last blocks in the pas= t. + */ + uint32_t block_length =3D MIN(s->block_size, + bs->total_sectors * BDRV_SECTOR_SIZE - i * s->block_size); + /* + * Check for BAT entry overflow. + */ + if (offset > INT64_MAX - s->block_size) { + error_report("VHDX BAT entry %" PRIu64 " offset overflow."= , i); + ret =3D -EINVAL; + if (!errcnt) { + break; + } + (*errcnt)++; + } + /* + * Check if fully allocated BAT entries do not reside after + * end of the image file. + */ + if (offset >=3D image_file_size) { + error_report("VHDX BAT entry %" PRIu64 " start offset %" P= RIu64 + " points after end of file (%" PRIi64 "). Ima= ge" + " has probably been truncated.", + i, offset, image_file_size); + ret =3D -EINVAL; + if (!errcnt) { + break; + } + (*errcnt)++; + } else if (offset + block_length > image_file_size) { + error_report("VHDX BAT entry %" PRIu64 " end offset %" PRI= u64 + " points after end of file (%" PRIi64 "). Ima= ge" + " has probably been truncated.", + i, offset + block_length - 1, image_file_size= ); + ret =3D -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 =3D vhdx_region_check(s, offset, s->block_size); + if (ret2 < 0) { + ret =3D -EINVAL; + if (!errcnt) { + break; + } + (*errcnt)++; + } + } else { + payblocks =3D s->chunk_ratio; + /* + * Once differencing files are supported, verify sector bi= tmap + * blocks here + */ + } + } + } + + return ret; +} + static void vhdx_close(BlockDriverState *bs) { BDRVVHDXState *s =3D bs->opaque; @@ -981,25 +1074,15 @@ static int vhdx_open(BlockDriverState *bs, QDict *op= tions, int flags, goto fail; } =20 - uint64_t payblocks =3D s->chunk_ratio; - /* endian convert, and verify populated BAT field file offsets against - * region table and log entries */ + /* endian convert populated BAT field entires */ for (i =3D 0; i < s->bat_entries; i++) { s->bat[i] =3D le64_to_cpu(s->bat[i]); - if (payblocks--) { - /* payload bat entries */ - if ((s->bat[i] & VHDX_BAT_STATE_BIT_MASK) =3D=3D - PAYLOAD_BLOCK_FULLY_PRESENT) { - ret =3D vhdx_region_check(s, s->bat[i] & VHDX_BAT_FILE_OFF= _MASK, - s->block_size); - if (ret < 0) { - goto fail; - } - } - } else { - payblocks =3D s->chunk_ratio; - /* Once differencing files are supported, verify sector bitmap - * blocks here */ + } + + if (!(flags & BDRV_O_CHECK)) { + ret =3D vhdx_check_bat_entries(bs, NULL); + if (ret < 0) { + goto fail; } } =20 @@ -2072,6 +2155,9 @@ static int coroutine_fn vhdx_co_check(BlockDriverStat= e *bs, if (s->log_replayed_on_open) { result->corruptions_fixed++; } + + vhdx_check_bat_entries(bs, &result->corruptions); + return 0; } =20 --=20 2.17.1