From 8ca56e9e0b878a90bac9860e971b0d849d7a83e7 Mon Sep 17 00:00:00 2001
From: Frans Kaashoek <kaashoek@mit.edu>
Date: Wed, 1 Sep 2021 07:29:12 -0400
Subject: [PATCH] =?UTF-8?q?memmove(dst,=20src,=200)=20leads=20to=20overflo?=
 =?UTF-8?q?w=20in=20`while(n--=20>=200)`=20as=20`n`=20is=20uint64=20(thank?=
 =?UTF-8?q?s=20Mat=C3=BA=C5=A1=20J=C3=B3kay=20<matus.jokay@stuba.sk>)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 kernel/string.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/string.c b/kernel/string.c
index d99e612..153536f 100644
--- a/kernel/string.c
+++ b/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){