1 files changed, 2 insertions, 0 deletions
diff --git a/src/heap.c b/src/heap.c
index 52b5253..9a11cba 100644
--- a/src/heap.c
+++ b/src/heap.c
@@ -76,6 +76,8 @@ void free(void *buf)
 		return;
 
 	alloc_t *alloc = (alloc_t *)((uint8_t *)buf - sizeof(alloc_t));
+	if (alloc->next != 0)
+		return;
 	heap_used -= alloc->size;
 	alloc->next = free_blocks;
 	free_blocks = alloc;