[IPV6]: Fix sending extension headers before and including routing header.

Based on suggestion from Masahide Nakamura <nakam@linux-ipv6.org>.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

4 files changed, 31 insertions, 12 deletions

diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index 748577b76d75..be6faf311387 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -673,3 +673,22 @@ out:
         return ERR_PTR(err);
 }
 
+struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
+                                          struct ipv6_txoptions *opt)
+{
+        /*
+         * ignore the dest before srcrt unless srcrt is being included.
+         * --yoshfuji
+         */
+        if (opt && opt->dst0opt && !opt->srcrt) {
+                if (opt_space != opt) {
+                        memcpy(opt_space, opt, sizeof(*opt_space));
+                        opt = opt_space;
+                }
+                opt->opt_nflen -= ipv6_optlen(opt->dst0opt);
+                opt->dst0opt = NULL;
+        }
+
+        return opt;
+}
+
diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
index bbbe80cdaf72..1cf02765fb5c 100644
--- a/net/ipv6/ip6_flowlabel.c
+++ b/net/ipv6/ip6_flowlabel.c
@@ -225,20 +225,16 @@ struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space,
                                          struct ip6_flowlabel * fl,
                                          struct ipv6_txoptions * fopt)
 {
-        struct ipv6_txoptions * fl_opt = fl ? fl->opt : NULL;
-
-        if (fopt == NULL || fopt->opt_flen == 0) {
-                if (!fl_opt || !fl_opt->dst0opt || fl_opt->srcrt)
-                        return fl_opt;
-        }
-
+        struct ipv6_txoptions * fl_opt = fl->opt;
+        
+        if (fopt == NULL || fopt->opt_flen == 0)
+                return fl_opt;
+        
         if (fl_opt != NULL) {
                 opt_space->hopopt = fl_opt->hopopt;
-                opt_space->dst0opt = fl_opt->srcrt ? fl_opt->dst0opt : NULL;
+                opt_space->dst0opt = fl_opt->dst0opt;
                 opt_space->srcrt = fl_opt->srcrt;
                 opt_space->opt_nflen = fl_opt->opt_nflen;
-                if (fl_opt->dst0opt && !fl_opt->srcrt)
-                        opt_space->opt_nflen -= ipv6_optlen(fl_opt->dst0opt);
         } else {
                 if (fopt->opt_nflen == 0)
                         return fopt;
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index a1265a320b11..d77d3352c967 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -756,7 +756,9 @@ static int rawv6_sendmsg(struct kiocb *iocb, struct sock *sk,
         }
         if (opt == NULL)
                 opt = np->opt;
-        opt = fl6_merge_options(&opt_space, flowlabel, opt);
+        if (flowlabel)
+                opt = fl6_merge_options(&opt_space, flowlabel, opt);
+        opt = ipv6_fixup_options(&opt_space, opt);
 
         fl.proto = proto;
         rawv6_probe_proto_opt(&fl, msg);
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index bf9519341fd3..e2b87cc68b7b 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -778,7 +778,9 @@ do_udp_sendmsg:
         }
         if (opt == NULL)
                 opt = np->opt;
-        opt = fl6_merge_options(&opt_space, flowlabel, opt);
+        if (flowlabel)
+                opt = fl6_merge_options(&opt_space, flowlabel, opt);
+        opt = ipv6_fixup_options(&opt_space, opt);
 
         fl->proto = IPPROTO_UDP;
         ipv6_addr_copy(&fl->fl6_dst, daddr);