'

beware_overflow/beware_overflow.c

@@ -0,0 +1,11 @@
+#include "beware_overflow.h"
+
+void *beware_overflow(void *ptr, size_t nmemb, size_t size)
+{
+    size_t c;
+    if (__builtin_mul_overflow(nmemb, size, &c))
+        return NULL;
+
+    char *byte_ptr = ptr;
+    return c + byte_ptr;
+}