qcow2: Check snapshot L1 table in qcow2_snapshot_goto()

This function copies a snapshot's L1 table into the active one without
validating it first.

We now have a function to take care of this, so let's use it.

Cc: Eric Blake <eblake@redhat.com>
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/block/qcow2-snapshot.c b/block/qcow2-snapshot.c
index bf94f4f434..0faf728dc4 100644
--- a/block/qcow2-snapshot.c
+++ b/block/qcow2-snapshot.c
@@ -465,6 +465,7 @@ int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
 {
     BDRVQcow2State *s = bs->opaque;
     QCowSnapshot *sn;
+    Error *local_err = NULL;
     int i, snapshot_index;
     int cur_l1_bytes, sn_l1_bytes;
     int ret;
@@ -477,6 +478,14 @@ int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
     }
     sn = &s->snapshots[snapshot_index];
 
+    ret = qcow2_validate_table(bs, sn->l1_table_offset, sn->l1_size,
+                               sizeof(uint64_t), QCOW_MAX_L1_SIZE,
+                               "Snapshot L1 table", &local_err);
+    if (ret < 0) {
+        error_report_err(local_err);
+        goto fail;
+    }
+
     if (sn->disk_size != bs->total_sectors * BDRV_SECTOR_SIZE) {
         error_report("qcow2: Loading snapshots with different disk "
             "size is not implemented");