[src/trunk]: src/usr.sbin/rtadvd Check valid lengths of RDNSS and DNSSL optio...

[roy <roy%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/8aecd7dc43b7
branches:  trunk
changeset: 787647:8aecd7dc43b7
user:      roy <roy%NetBSD.org@localhost>
date:      Thu Jun 27 15:46:40 2013 +0000

description:
Check valid lengths of RDNSS and DNSSL options when rtadvd receives RA/RS.
rtadvd doesn't actually look into the option itself, but it may do in the
future to warn about consistency.

diffstat:

 usr.sbin/rtadvd/rtadvd.c |  12 ++++++++++--
 1 files changed, 10 insertions(+), 2 deletions(-)

diffs (33 lines):

diff -r 88ed07250d55 -r 8aecd7dc43b7 usr.sbin/rtadvd/rtadvd.c
--- a/usr.sbin/rtadvd/rtadvd.c  Thu Jun 27 15:27:46 2013 +0000
+++ b/usr.sbin/rtadvd/rtadvd.c  Thu Jun 27 15:46:40 2013 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: rtadvd.c,v 1.41 2012/12/14 09:48:31 roy Exp $  */
+/*     $NetBSD: rtadvd.c,v 1.42 2013/06/27 15:46:40 roy Exp $  */
 /*     $KAME: rtadvd.c,v 1.92 2005/10/17 14:40:02 suz Exp $    */
 
 /*
@@ -1379,7 +1379,13 @@
                if ((hdr->nd_opt_type == ND_OPT_MTU &&
                    (optlen != sizeof(struct nd_opt_mtu))) ||
                    ((hdr->nd_opt_type == ND_OPT_PREFIX_INFORMATION &&
-                   optlen != sizeof(struct nd_opt_prefix_info)))) {
+                   optlen != sizeof(struct nd_opt_prefix_info))) ||
+                   (hdr->nd_opt_type == ND_OPT_RDNSS &&
+                   ((optlen < (int)sizeof(struct nd_opt_rdnss) ||
+                   (optlen - sizeof(struct nd_opt_rdnss)) % 16 != 0))) ||
+                   (hdr->nd_opt_type == ND_OPT_DNSSL &&
+                   optlen < (int)sizeof(struct nd_opt_dnssl)))
+               {
                        syslog(LOG_INFO, "<%s> invalid option length",
                            __func__);
                        continue;
@@ -1388,6 +1394,8 @@
                switch (hdr->nd_opt_type) {
                case ND_OPT_TARGET_LINKADDR:
                case ND_OPT_REDIRECTED_HEADER:
+               case ND_OPT_RDNSS:
+               case ND_OPT_DNSSL:
                        break;  /* we don't care about these options */
                case ND_OPT_SOURCE_LINKADDR:
                case ND_OPT_MTU: