memmove(dst, src, 0) leads to overflow in while(n-- > 0) as n is uint64 (thanks

Matúš Jókay <matus.jokay@stuba.sk>)

kernel/string.c

@@ -33,6 +33,9 @@ memmove(void *dst, const void *src, uint n)
   const char *s;
   char *d;
 
+  if(n == 0)
+    return dst;
+  
   s = src;
   d = dst;
   if(s < d && s + n > d){