14.07.2017 13:42, Peter Maydell wrote:
On 11 July 2017 at 17:07, Max Reitz <mre...@redhat.com> wrote:
From: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Realize .bdrv_remove_persistent_dirty_bitmap interface.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Reviewed-by: Max Reitz <mre...@redhat.com>
Reviewed-by: John Snow <js...@redhat.com>
Message-id: 20170628120530.31251-29-vsement...@virtuozzo.com
Signed-off-by: Max Reitz <mre...@redhat.com>
+void qcow2_remove_persistent_dirty_bitmap(BlockDriverState *bs,
+ const char *name,
+ Error **errp)
+{
+ int ret;
+ BDRVQcow2State *s = bs->opaque;
+ Qcow2Bitmap *bm;
+ Qcow2BitmapList *bm_list;
+
+ if (s->nb_bitmaps == 0) {
+ /* Absence of the bitmap is not an error: see explanation above
+ * bdrv_remove_persistent_dirty_bitmap() definition. */
+ return;
+ }
+
+ bm_list = bitmap_list_load(bs, s->bitmap_directory_offset,
+ s->bitmap_directory_size, errp);
+ if (bm_list == NULL) {
+ return;
+ }
+
+ bm = find_bitmap_by_name(bm_list, name);
+ if (bm == NULL) {
+ goto fail;
+ }
+
+ QSIMPLEQ_REMOVE(bm_list, bm, Qcow2Bitmap, entry);
+
+ ret = update_ext_header_and_dir(bs, bm_list);
+ if (ret < 0) {
+ error_setg_errno(errp, -ret, "Failed to update bitmap extension");
+ goto fail;
+ }
+
+ free_bitmap_clusters(bs, &bm->table);
+
+fail:
+ bitmap_free(bm);
+ bitmap_list_free(bm_list);
+}
Coverity points out that this can crash in the error-exit paths,
because bitmap_free() doesn't handle being passed a NULL pointer.
(CID 1377700).
Probably the best fix for this is to make bitmap_free() do
nothing when handed NULL.
Agree, my stupid omission. Can this be fixed in flight? Just squash into
commit "qcow2: add bitmaps extension"
diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c
index 8448bec46d..39dfe16fc0 100644
--- a/block/qcow2-bitmap.c
+++ b/block/qcow2-bitmap.c
@@ -487,6 +487,10 @@ static inline void bitmap_directory_to_be(uint8_t
*dir, size_t size)
static void bitmap_free(Qcow2Bitmap *bm)
{
+ if (bm == NULL) {
+ return;
+ }
+
g_free(bm->name);
g_free(bm);
}
//
thanks
-- PMM
--
Best regards,
Vladimir
