From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60088) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VN4j6-0003RY-Bi for qemu-devel@nongnu.org; Fri, 20 Sep 2013 13:42:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VN4j0-0005Dt-5C for qemu-devel@nongnu.org; Fri, 20 Sep 2013 13:42:44 -0400 Received: from mx1.redhat.com ([209.132.183.28]:46082) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VN4iz-0005DZ-Q7 for qemu-devel@nongnu.org; Fri, 20 Sep 2013 13:42:38 -0400 From: Stefan Hajnoczi Date: Fri, 20 Sep 2013 19:42:08 +0200 Message-Id: <1379698931-946-9-git-send-email-stefanha@redhat.com> In-Reply-To: <1379698931-946-1-git-send-email-stefanha@redhat.com> References: <1379698931-946-1-git-send-email-stefanha@redhat.com> Subject: [Qemu-devel] [PULL 08/11] qcow2: Correct snapshots size for overlap check List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Stefan Hajnoczi , Anthony Liguori , Max Reitz From: Max Reitz 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 --- block/qcow2-snapshot.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c index 7d14420..5e8a779 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; } -- 1.8.3.1