diff --git a/qemu-malloc.c b/qemu-malloc.c
index 6761857..5e9f47f 100644
--- a/qemu-malloc.c
+++ b/qemu-malloc.c
@@ -43,6 +43,8 @@
 
 void *qemu_malloc(size_t size)
 {
+    if (!size)
+        abort();
     return oom_check(malloc(size));
 }
 
@@ -50,8 +52,11 @@
 {
     if (size)
         return oom_check(realloc(ptr, size));
-    else
-        return realloc(ptr, size);
+    else {
+        if (ptr)
+            return realloc(ptr, size);
+    }
+    abort();
 }
 
 void *qemu_mallocz(size_t size)