md/bitmap: fix memory leak of temporary bitmap

Callers of get_bitmap_from_slot() are responsible to free the bitmap.
Suggested-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Zhao Heming <heming.zhao@suse.com>
Signed-off-by: Song Liu <songliubraving@fb.com>

drivers/md/md-bitmap.c

@@ -1950,6 +1950,7 @@ int md_bitmap_load(struct mddev *mddev)
 }
 EXPORT_SYMBOL_GPL(md_bitmap_load);
 
+/* caller need to free returned bitmap with md_bitmap_free() */
 struct bitmap *get_bitmap_from_slot(struct mddev *mddev, int slot)
 {
 	int rv = 0;
@@ -2013,6 +2014,7 @@ int md_bitmap_copy_from_slot(struct mddev *mddev, int slot,
 	md_bitmap_unplug(mddev->bitmap);
 	*low = lo;
 	*high = hi;
+	md_bitmap_free(bitmap);
 
 	return rv;
 }
@@ -2616,4 +2618,3 @@ struct attribute_group md_bitmap_group = {
 	.name = "bitmap",
 	.attrs = md_bitmap_attrs,
 };
-

drivers/md/md-cluster.c

@@ -1166,6 +1166,7 @@ static int resize_bitmaps(struct mddev *mddev, sector_t newsize, sector_t oldsiz
 			 * can't resize bitmap
 			 */
 			goto out;
+		md_bitmap_free(bitmap);
 	}
 
 	return 0;