md/bitmap: fix memory leak of temporary bitmap

Callers of get_bitmap_from_slot() are responsible to free the bitmap.

Suggested-by: Guoqing Jiang <[e-mail]>
Signed-off-by: Zhao Heming <[e-mail]>
Signed-off-by: Song Liu <[e-mail]>

drivers/md/md-bitmap.c

···
 }
 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;
···
 	md_bitmap_unplug(mddev->bitmap);
 	*low = lo;
 	*high = hi;
+	md_bitmap_free(bitmap);
 
 	return rv;
 }
···
 	.name = "bitmap",
 	.attrs = md_bitmap_attrs,
 };
-

drivers/md/md-cluster.c

···
 			 * can't resize bitmap
 			 */
 			goto out;
+		md_bitmap_free(bitmap);
 	}
 
 	return 0;