safe handling of realloc()

src/utils.c

@@ -168,12 +168,12 @@ realloc_buffer(
     if (!buffer_p || !max_elements_p)
         return NULL;
 
-    void *buffer = *buffer_p;
     if (*max_elements_p > num_elements)
-        return buffer;
+        return *buffer_p;
 
+    void *buffer;
     num_elements += 4;
-    if ((buffer = realloc(buffer, num_elements * element_size)) == NULL) {
+    if ((buffer = realloc(*buffer_p, num_elements * element_size)) == NULL) {
         free(*buffer_p);
         *buffer_p = NULL;
         return NULL;

src/xvba_subpic.c

@@ -54,7 +54,7 @@ subpicture_add_association(
 )
 {
     SubpictureAssociationP *assocs;
-    assocs = realloc_buffer(&obj_subpicture->assocs,
+    assocs = realloc_buffer((void **)&obj_subpicture->assocs,
                             &obj_subpicture->assocs_count_max,
                             1 + obj_subpicture->assocs_count,
                             sizeof(obj_subpicture->assocs[0]));
@@ -94,8 +94,14 @@ subpicture_remove_association(
 
     unsigned int i;
     for (i = 0; i < obj_subpicture->assocs_count; i++) {
-        if (obj_subpicture->assocs[i] == assoc)
-            return subpicture_remove_association_at(obj_subpicture, i);
+        if (obj_subpicture->assocs[i] == assoc) {
+            /* Free association at 'index' */
+            SubpictureAssociationP a = obj_subpicture->assocs[i];
+            ASSERT(a);
+            int idx = subpicture_remove_association_at(obj_subpicture, i);
+            free(a);
+            return idx;
+        }
     }
     return -1;
 }