[Qemu-devel] [PATCH 18/29] qcow2-bitmap: disallow storing bitmap to other bs

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

Check, that bitmap is stored to the owning bs.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
---
 block/dirty-bitmap.c         | 12 ++++++++++++
 block/qcow2-bitmap.c         |  5 +++++
 include/block/dirty-bitmap.h |  2 ++
 3 files changed, 19 insertions(+)

diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c
index 1d0ea25..90ac794 100644
--- a/block/dirty-bitmap.c
+++ b/block/dirty-bitmap.c
@@ -613,3 +613,15 @@ BdrvDirtyBitmap *bdrv_load_dirty_bitmap(BlockDriverState *bs, const char *name,
     }
     return NULL;
 }
+
+bool bdrv_has_dirty_bitmap(BlockDriverState *bs, const BdrvDirtyBitmap *bitmap)
+{
+    BdrvDirtyBitmap *bm, *next;
+    QLIST_FOREACH_SAFE(bm, &bs->dirty_bitmaps, list, next) {
+        if (bm == bitmap) {
+            return true;
+        }
+    }
+
+    return false;
+}
diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c
index 0e95121..bfc1db8 100644
--- a/block/qcow2-bitmap.c
+++ b/block/qcow2-bitmap.c
@@ -881,6 +881,11 @@ void qcow2_bitmap_store(BlockDriverState *bs,
     uint32_t table_size;
     uint64_t *bitmap_table;
 
+    if (!bdrv_has_dirty_bitmap(bs, bitmap)) {
+        error_setg(errp, "Can't store bitmap to the other node.");
+        return;
+    }
+
     /* find/create dirty bitmap */
     bmh = find_bitmap_by_name(bs, bm_name);
     if (bmh != NULL) {
diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h
index d482098..1af3890 100644
--- a/include/block/dirty-bitmap.h
+++ b/include/block/dirty-bitmap.h
@@ -84,4 +84,6 @@ void bdrv_finalize_persistent_dirty_bitmaps(BlockDriverState *bs);
 BdrvDirtyBitmap *bdrv_load_dirty_bitmap(BlockDriverState *bs, const char *name,
                                         Error **errp);
 
+bool bdrv_has_dirty_bitmap(BlockDriverState *bs, const BdrvDirtyBitmap *bitmap);
+
 #endif
-- 
1.8.3.1