[src/trunk]: src/sys/netinet6 Kick nested fragments.

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

details:   https://anonhg.NetBSD.org/src/rev/99e285bcfc0b
branches:  trunk
changeset: 359122:99e285bcfc0b
user:      maxv <maxv%NetBSD.org@localhost>
date:      Tue Jan 30 15:35:31 2018 +0000

description:
Kick nested fragments.

diffstat:

 sys/netinet6/ip6_input.c |  13 ++++++++++---
 1 files changed, 10 insertions(+), 3 deletions(-)

diffs (48 lines):

diff -r a71d2a1d5163 -r 99e285bcfc0b sys/netinet6/ip6_input.c
--- a/sys/netinet6/ip6_input.c  Tue Jan 30 15:28:39 2018 +0000
+++ b/sys/netinet6/ip6_input.c  Tue Jan 30 15:35:31 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ip6_input.c,v 1.187 2018/01/30 14:49:25 maxv Exp $     */
+/*     $NetBSD: ip6_input.c,v 1.188 2018/01/30 15:35:31 maxv Exp $     */
 /*     $KAME: ip6_input.c,v 1.188 2001/03/29 05:34:31 itojun Exp $     */
 
 /*
@@ -62,7 +62,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ip6_input.c,v 1.187 2018/01/30 14:49:25 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ip6_input.c,v 1.188 2018/01/30 15:35:31 maxv Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_gateway.h"
@@ -248,7 +248,7 @@
        int hit, off = sizeof(struct ip6_hdr), nest;
        u_int32_t plen;
        u_int32_t rtalert = ~0;
-       int nxt, ours = 0, rh_present = 0;
+       int nxt, ours = 0, rh_present = 0, frg_present;
        struct ifnet *deliverifp = NULL;
        int srcrt = 0;
        struct rtentry *rt = NULL;
@@ -741,6 +741,7 @@
        percpu_putref(ip6_forward_rt_percpu);
 
        rh_present = 0;
+       frg_present = 0;
        while (nxt != IPPROTO_DONE) {
                if (ip6_hdrnestlimit && (++nest > ip6_hdrnestlimit)) {
                        IP6_STATINC(IP6_STAT_TOOMANYHDR);
@@ -764,6 +765,12 @@
                                IP6_STATINC(IP6_STAT_BADOPTIONS);
                                goto bad;
                        }
+               } else if (nxt == IPPROTO_FRAGMENT) {
+                       if (frg_present++) {
+                               in6_ifstat_inc(rcvif, ifs6_in_hdrerr);
+                               IP6_STATINC(IP6_STAT_BADOPTIONS);
+                               goto bad;
+                       }
                }
 
 #ifdef IPSEC