erts: Fix bug for remote control message containing fat maps

that could cause the static factory to overflow

Fix: Introduce a new factory mode FACTORY_TMP

1 files changed, 27 insertions, 2 deletions

diff --git a/erts/emulator/beam/erl_message.c b/erts/emulator/beam/erl_message.c
index 2a703fb102..fa6b2fc613 100644
--- a/erts/emulator/beam/erl_message.c
+++ b/erts/emulator/beam/erl_message.c
@@ -1174,6 +1174,9 @@ void erts_factory_message_init(ErtsHeapFactory* factory,
     ASSERT(factory->hp >= factory->hp_start && factory->hp <= factory->hp_end);
 }
 
+/* One static sized heap that must suffice.
+   No extra heap fragments will be allocated.
+*/
 void erts_factory_static_init(ErtsHeapFactory* factory,
 			     Eterm* hp,
 			     Uint size,
@@ -1188,6 +1191,23 @@ void erts_factory_static_init(ErtsHeapFactory* factory,
     factory->off_heap_saved.overhead = factory->off_heap->overhead;
 }
 
+/* A temporary heap with default buffer allocated/freed by client.
+ * factory_close is same as factory_undo
+ */
+void erts_factory_tmp_init(ErtsHeapFactory* factory, Eterm* hp, Uint size,
+			   Uint32 atype)
+{
+    factory->mode     = FACTORY_TMP;
+    factory->hp_start = hp;
+    factory->hp       = hp;
+    factory->hp_end   = hp + size;
+    factory->heap_frags = NULL;
+    factory->off_heap_saved.first    = NULL;
+    factory->off_heap_saved.overhead = 0;
+    factory->off_heap = &factory->off_heap_saved;
+    factory->alloc_type = atype;
+}
+
 /* When we know the term is an immediate and need no heap.
 */
 void erts_factory_dummy_init(ErtsHeapFactory* factory)
@@ -1231,6 +1251,7 @@ static void reserve_heap(ErtsHeapFactory* factory, Uint need, Uint xtra)
 	return;
 
     case FACTORY_HEAP_FRAGS:
+    case FACTORY_TMP:
 	bp = factory->heap_frags;
 
         if (bp) {
@@ -1280,6 +1301,9 @@ void erts_factory_close(ErtsHeapFactory* factory)
 	    bp->used_size = factory->hp - bp->mem;
         }
 	break;
+    case FACTORY_TMP:
+	erts_factory_undo(factory);
+	break;
     case FACTORY_STATIC: break;
     case FACTORY_CLOSED: break;
     default:
@@ -1371,19 +1395,20 @@ void erts_factory_undo(ErtsHeapFactory* factory)
         }
         break;
 
+    case FACTORY_TMP:
     case FACTORY_HEAP_FRAGS:
 	erts_cleanup_offheap(factory->off_heap);
 	factory->off_heap->first = NULL;
 
         bp = factory->heap_frags;
-        do {
+        while (bp != NULL) {
             ErlHeapFragment* next_bp = bp->next;
 
             ASSERT(bp->off_heap.first == NULL);
             ERTS_HEAP_FREE(factory->alloc_type, (void *) bp,
                            ERTS_HEAP_FRAG_SIZE(bp->alloc_size));
             bp = next_bp;
-        }while (bp != NULL);
+        }
 	break;
 
     case FACTORY_CLOSED: break;