From f9b42568a13151521cb8edf38f567e8c5cf25396 Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Mon, 4 Nov 2013 22:32:23 +0100 Subject: [PATCH 30/87] qcow2: Correct snapshots size for overlap check RH-Author: Max Reitz Message-id: <1383604354-12743-33-git-send-email-mreitz@redhat.com> Patchwork-id: 55332 O-Subject: [RHEL-7.0 qemu-kvm PATCH 32/43] qcow2: Correct snapshots size for overlap check Bugzilla: 1004347 RH-Acked-by: Kevin Wolf RH-Acked-by: Laszlo Ersek RH-Acked-by: Fam Zheng RH-Acked-by: Stefan Hajnoczi BZ: 1004347 Using s->snapshots_size instead of snapshots_size for the metadata overlap check in qcow2_write_snapshots leads to the detection of an overlap with the main qcow2 image header when deleting the last snapshot, since s->snapshots_size has not yet been updated and is therefore non-zero. However, the offset returned by qcow2_alloc_clusters will be zero since snapshots_size is zero. Therefore, an overlap is detected albeit no such will occur. This patch fixes this by replacing s->snapshots_size by snapshots_size when calling qcow2_pre_write_overlap_check. Signed-off-by: Max Reitz Signed-off-by: Stefan Hajnoczi (cherry picked from commit 0f39ac9a07cc10278e37d87076b143008f28aa3b) Signed-off-by: Max Reitz --- block/qcow2-snapshot.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Signed-off-by: Miroslav Rezanina --- block/qcow2-snapshot.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c index e7e6013..450e4f5 100644 --- a/block/qcow2-snapshot.c +++ b/block/qcow2-snapshot.c @@ -192,7 +192,7 @@ static int qcow2_write_snapshots(BlockDriverState *bs) /* The snapshot list position has not yet been updated, so these clusters * must indeed be completely free */ ret = qcow2_pre_write_overlap_check(bs, QCOW2_OL_DEFAULT, offset, - s->snapshots_size); + snapshots_size); if (ret < 0) { return ret; } -- 1.7.1