From 17f83612c866a213d6786eeb36123cec5c39c527 Mon Sep 17 00:00:00 2001 Message-Id: <17f83612c866a213d6786eeb36123cec5c39c527.1369658547.git.minovotn@redhat.com> In-Reply-To: <07146f8b79923c529fd93fa528e6fcbd6f571a02.1369658547.git.minovotn@redhat.com> References: <07146f8b79923c529fd93fa528e6fcbd6f571a02.1369658547.git.minovotn@redhat.com> From: Fam Zheng Date: Mon, 20 May 2013 03:36:53 +0200 Subject: [PATCH 38/47] vmdk: Fix data corruption bug in WRITE and READ handling RH-Author: Fam Zheng Message-id: <1369021022-22728-39-git-send-email-famz@redhat.com> Patchwork-id: 51474 O-Subject: [PATCH RHEL-6.5 qemu-kvm v3 38/47] vmdk: Fix data corruption bug in WRITE and READ handling Bugzilla: 960685 RH-Acked-by: Stefan Hajnoczi RH-Acked-by: Jeffrey Cody RH-Acked-by: Kevin Wolf From: Gerhard Wiesinger Fixed a MAJOR BUG in VMDK files on file boundaries on reads and ALSO ON WRITES WHICH MIGHT CORRUPT THE IMAGE AND DATA!!!!!! Triggered for example with the following VMDK file (partly listed): RW 4193792 FLAT "XP-W1-f001.vmdk" 0 RW 2097664 FLAT "XP-W1-f002.vmdk" 0 RW 4193792 FLAT "XP-W1-f003.vmdk" 0 RW 512 FLAT "XP-W1-f004.vmdk" 0 RW 4193792 FLAT "XP-W1-f005.vmdk" 0 RW 2097664 FLAT "XP-W1-f006.vmdk" 0 RW 4193792 FLAT "XP-W1-f007.vmdk" 0 RW 512 FLAT "XP-W1-f008.vmdk" 0 Patch includes: 1.) Patch fixes wrong calculation on extent boundaries. Especially it fixes the relativeness of the sector number to the current extent. Verfied correctness with: 1.) Converted either with Virtualbox to VDI and then with qemu-img and then with qemu-img only: VBoxManage clonehd --format vdi /VM/XP-W/new/XP-W1.vmdk ~/.VirtualBox/Harddisks/XP-W1-new-test.vdi ./qemu-img convert -O raw ~/.VirtualBox/Harddisks/XP-W1-new-test.vdi /root/QEMU/VM-XP-W1/XP-W1-via-VBOX.img md5sum /root/QEMU/VM-XP-W/XP-W1-direct.img md5sum /root/QEMU/VM-XP-W/XP-W1-via-VBOX.img => same MD5 hash 2.) Verified debug log files 3.) Run Windows XP successfully 4.) chkdsk run successfully without any errors Signed-off-by: Gerhard Wiesinger Acked-by: Fam Zheng Signed-off-by: Kevin Wolf (cherry picked from commit b1649fae49a899a222c3ac53c5009dd6f23349e1) Signed-off-by: Fam Zheng --- block/vmdk.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) Signed-off-by: Michal Novotny --- block/vmdk.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/block/vmdk.c b/block/vmdk.c index c1e83ba..a4ced38 100644 --- a/block/vmdk.c +++ b/block/vmdk.c @@ -1083,6 +1083,7 @@ static int vmdk_read(BlockDriverState *bs, int64_t sector_num, BDRVVmdkState *s = bs->opaque; int ret; uint64_t n, index_in_cluster; + uint64_t extent_begin_sector, extent_relative_sector_num; VmdkExtent *extent = NULL; uint64_t cluster_offset; @@ -1094,7 +1095,9 @@ static int vmdk_read(BlockDriverState *bs, int64_t sector_num, ret = get_cluster_offset( bs, extent, NULL, sector_num << 9, 0, &cluster_offset); - index_in_cluster = sector_num % extent->cluster_sectors; + extent_begin_sector = extent->end_sector - extent->sectors; + extent_relative_sector_num = sector_num - extent_begin_sector; + index_in_cluster = extent_relative_sector_num % extent->cluster_sectors; n = extent->cluster_sectors - index_in_cluster; if (n > nb_sectors) { n = nb_sectors; @@ -1145,6 +1148,7 @@ static int vmdk_write(BlockDriverState *bs, int64_t sector_num, VmdkExtent *extent = NULL; int n, ret; int64_t index_in_cluster; + uint64_t extent_begin_sector, extent_relative_sector_num; uint64_t cluster_offset; VmdkMetaData m_data; @@ -1187,7 +1191,9 @@ static int vmdk_write(BlockDriverState *bs, int64_t sector_num, if (ret) { return -EINVAL; } - index_in_cluster = sector_num % extent->cluster_sectors; + extent_begin_sector = extent->end_sector - extent->sectors; + extent_relative_sector_num = sector_num - extent_begin_sector; + index_in_cluster = extent_relative_sector_num % extent->cluster_sectors; n = extent->cluster_sectors - index_in_cluster; if (n > nb_sectors) { n = nb_sectors; -- 1.7.11.7