1 files changed, 7 insertions, 5 deletions

diff --git a/block.c b/block.c
index 6c2b2bd2e2..9c810534d6 100644
--- a/block.c
+++ b/block.c
@@ -1998,18 +1998,19 @@ char *bdrv_perm_names(uint64_t perm)
         { 0, NULL }
     };
 
-    char *result = g_strdup("");
+    GString *result = g_string_sized_new(30);
     struct perm_name *p;
 
     for (p = permissions; p->name; p++) {
         if (perm & p->perm) {
-            char *old = result;
-            result = g_strdup_printf("%s%s%s", old, *old ? ", " : "", p->name);
-            g_free(old);
+            if (result->len > 0) {
+                g_string_append(result, ", ");
+            }
+            g_string_append(result, p->name);
         }
     }
 
-    return result;
+    return g_string_free(result, FALSE);
 }
 
 /*
@@ -6441,6 +6442,7 @@ void bdrv_refresh_filename(BlockDriverState *bs)
                 child->bs->exact_filename);
         pstrcpy(bs->filename, sizeof(bs->filename), child->bs->filename);
 
+        qobject_unref(bs->full_open_options);
         bs->full_open_options = qobject_ref(child->bs->full_open_options);
 
         return;