[src/trunk]: src/sys/netinet Fix usage of curlwp_bind in ip_output

[ozaki-r <ozaki-r%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/7bb955d5f0c7
branches:  trunk
changeset: 828633:7bb955d5f0c7
user:      ozaki-r <ozaki-r%NetBSD.org@localhost>
date:      Fri Dec 22 11:22:37 2017 +0000

description:
Fix usage of curlwp_bind in ip_output

curlwp_bindx must be called in LIFO order, i.e., we can't call curlwp_bind
and curlwp_bindx like this:
  bound1 = curlwp_bind();
  bound2 = curlwp_bind();
  curlwp_bindx(bound1);
  curlwp_bindx(bound2);

ip_outout did so if NET_MPSAFE. Fix it.

diffstat:

 sys/netinet/ip_output.c |  10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diffs (38 lines):

diff -r 7b33dacaeb45 -r 7bb955d5f0c7 sys/netinet/ip_output.c
--- a/sys/netinet/ip_output.c   Fri Dec 22 10:24:49 2017 +0000
+++ b/sys/netinet/ip_output.c   Fri Dec 22 11:22:37 2017 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ip_output.c,v 1.287 2017/12/15 04:03:46 ozaki-r Exp $  */
+/*     $NetBSD: ip_output.c,v 1.288 2017/12/22 11:22:37 ozaki-r Exp $  */
 
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -91,7 +91,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ip_output.c,v 1.287 2017/12/15 04:03:46 ozaki-r Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ip_output.c,v 1.288 2017/12/22 11:22:37 ozaki-r Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_inet.h"
@@ -303,6 +303,10 @@
            !in_hosteq(dst->sin_addr, ip->ip_dst)))
                rtcache_free(ro);
 
+       /* XXX must be before rtcache operations */
+       bound = curlwp_bind();
+       bind_need_restore = true;
+
        if ((rt = rtcache_validate(ro)) == NULL &&
            (rt = rtcache_update(ro, 1)) == NULL) {
                dst = &udst.sin;
@@ -311,8 +315,6 @@
                        goto bad;
        }
 
-       bound = curlwp_bind();
-       bind_need_restore = true;
        /*
         * If routing to interface only, short circuit routing lookup.
         */