Limit UDP payload size for EDNS0 to 0xffff, not use lower 16bit value.

from onoe@sm.sony.co.jp

1 files changed, 4 insertions, 2 deletions

diff --git a/src/lib/libc/net/res_mkquery.c b/src/lib/libc/net/res_mkquery.c
index 6e57ec3217..6cd6a00dbe 100644
--- a/src/lib/libc/net/res_mkquery.c
+++ b/src/lib/libc/net/res_mkquery.c
@@ -1,4 +1,4 @@
-/*      $OpenBSD: res_mkquery.c,v 1.11 2002/06/26 06:01:16 itojun Exp $ */
+/*      $OpenBSD: res_mkquery.c,v 1.12 2002/08/28 03:19:38 itojun Exp $ */
 
 /*
  * ++Copyright++ 1985, 1993
@@ -60,7 +60,7 @@
 static char sccsid[] = "@(#)res_mkquery.c       8.1 (Berkeley) 6/4/93";
 static char rcsid[] = "$From: res_mkquery.c,v 8.5 1996/08/27 08:33:28 vixie Exp $";
 #else
-static char rcsid[] = "$OpenBSD: res_mkquery.c,v 1.11 2002/06/26 06:01:16 itojun Exp $";
+static char rcsid[] = "$OpenBSD: res_mkquery.c,v 1.12 2002/08/28 03:19:38 itojun Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -217,6 +217,8 @@ res_opt(n0, buf, buflen, anslen)
 
         __putshort(T_OPT, cp);  /* TYPE */
         cp += INT16SZ;
+        if (anslen > 0xffff)
+                anslen = 0xffff;                /* limit to 16bit value */
         __putshort(anslen & 0xffff, cp);        /* CLASS = UDP payload size */
         cp += INT16SZ;
         *cp++ = NOERROR;        /* extended RCODE */