1 files changed, 10 insertions, 0 deletions
diff --git a/malloc/beware_overflow/beware_overflow.c b/malloc/beware_overflow/beware_overflow.c
new file mode 100644
index 0000000..4b2555c
--- /dev/null
+++ b/malloc/beware_overflow/beware_overflow.c
@@ -0,0 +1,10 @@
+#include "beware_overflow.h"
+
+void *beware_overflow(void *ptr, size_t nmemb, size_t size)
+{
+    size_t res;
+    if (__builtin_umull_overflow(nmemb, size, &res))
+        return NULL;
+    char *r = ptr;
+    return r + res;
+}