From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35132) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XlL3y-0001rT-9V for qemu-devel@nongnu.org; Mon, 03 Nov 2014 12:05:12 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XlL3s-000219-4E for qemu-devel@nongnu.org; Mon, 03 Nov 2014 12:05:06 -0500 Received: from mx1.redhat.com ([209.132.183.28]:55191) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XlL3r-00020x-SO for qemu-devel@nongnu.org; Mon, 03 Nov 2014 12:05:00 -0500 From: Max Reitz Date: Mon, 3 Nov 2014 18:04:28 +0100 Message-Id: <1415034271-8774-10-git-send-email-mreitz@redhat.com> In-Reply-To: <1415034271-8774-1-git-send-email-mreitz@redhat.com> References: <1415034271-8774-1-git-send-email-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH 09/12] qcow2/overlaps: Protect snapshot table List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , =?UTF-8?q?Beno=C3=AEt=20Canet?= , Peter Lieven , Max Reitz , Stefan Hajnoczi Keep track of the snapshot table in the metadata list to protect it against accidental modifications. Signed-off-by: Max Reitz --- block/qcow2-snapshot.c | 10 ++++++++++ block/qcow2.c | 6 ++++++ 2 files changed, 16 insertions(+) diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c index d83a939..c32d889 100644 --- a/block/qcow2-snapshot.c +++ b/block/qcow2-snapshot.c @@ -262,8 +262,18 @@ static int qcow2_write_snapshots(BlockDriverState *bs) /* free the old snapshot table */ qcow2_free_clusters(bs, s->snapshots_offset, s->snapshots_size, QCOW2_DISCARD_SNAPSHOT); + + qcow2_metadata_list_remove(bs, s->snapshots_offset, + size_to_clusters(s, s->snapshots_size), + QCOW2_OL_SNAPSHOT_TABLE); + s->snapshots_offset = snapshots_offset; s->snapshots_size = snapshots_size; + + qcow2_metadata_list_enter(bs, s->snapshots_offset, + size_to_clusters(s, s->snapshots_size), + QCOW2_OL_SNAPSHOT_TABLE); + return 0; fail: diff --git a/block/qcow2.c b/block/qcow2.c index d0950fc..468090d 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -798,6 +798,12 @@ static int qcow2_open(BlockDriverState *bs, QDict *options, int flags, error_setg(errp, "Invalid snapshot table offset"); goto fail; } + if (header.nb_snapshots) { + qcow2_metadata_list_enter(bs, header.snapshots_offset, + size_to_clusters(s, header.nb_snapshots * + sizeof(QCowSnapshotHeader)), + QCOW2_OL_SNAPSHOT_TABLE); + } /* read the level 1 table */ if (header.l1_size > QCOW_MAX_L1_SIZE) { -- 1.9.3