From Suse glibc-2.8.90-12.3 glibc-getgroups-fortify.diff

diff -Naur glibc-2.8-20080929.orig/posix/bits/unistd.h glibc-2.8-20080929/posix/bits/unistd.h
--- glibc-2.8-20080929.orig/posix/bits/unistd.h	2007-09-26 20:44:55.000000000 +0000
+++ glibc-2.8-20080929/posix/bits/unistd.h	2008-10-17 20:25:45.000000000 +0000
@@ -270,7 +270,8 @@
       if (!__builtin_constant_p (__size))
 	return __getgroups_chk (__size, __list, __bos (__list));
 
-      if (__size * sizeof (__gid_t) > __bos (__list))
+      if (__size > 0
+	  && __size * sizeof (__gid_t) > __bos (__list))
 	return __getgroups_chk_warn (__size, __list, __bos (__list));
     }
   return __getgroups_alias (__size, __list);