The ->rtm_tos option is normally used to route packets based on both
the destination address and the DS field. However it's ignored for
IPv6 routes. Setting ->rtm_tos for IPv6 is thus invalid as the route
is going to work only on the destination address anyway, so it won't
behave as specified.
Suggested-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
Signed-off-by: Guillaume Nault <gnault@xxxxxxxxxx>
---
The same problem exists for ->rtm_scope. I'm working only on ->rtm_tos
here because IPv4 recently started to validate this option too (as part
of the DSCP/ECN clarification effort).
I'll give this patch some soak time, then send another one for
rejecting ->rtm_scope in IPv6 routes if nobody complains.
net/ipv6/route.c | 6 ++++++
tools/testing/selftests/net/fib_tests.sh | 13 +++++++++++++
2 files changed, 19 insertions(+)
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index f4884cda13b9..dd98a11fbdb6 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -5009,6 +5009,12 @@ static int rtm_to_fib6_config(struct sk_buff *skb, struct nlmsghdr *nlh,
err = -EINVAL;
rtm = nlmsg_data(nlh);
+ if (rtm->rtm_tos) {
+ NL_SET_ERR_MSG(extack,
+ "Invalid dsfield (tos): option not available for IPv6");
+ goto errout;
+ }
+
*cfg = (struct fib6_config){
.fc_table = rtm->rtm_table,
.fc_dst_len = rtm->rtm_dst_len,
diff --git a/tools/testing/selftests/net/fib_tests.sh b/tools/testing/selftests/net/fib_tests.sh
index bb73235976b3..e2690cc42da3 100755
--- a/tools/testing/selftests/net/fib_tests.sh
+++ b/tools/testing/selftests/net/fib_tests.sh
@@ -988,12 +988,25 @@ ipv6_rt_replace()
ipv6_rt_replace_mpath
}
+ipv6_rt_dsfield()
+{
+ echo
+ echo "IPv6 route with dsfield tests"
+
+ run_cmd "$IP -6 route flush 2001:db8:102::/64"
+
+ # IPv6 doesn't support routing based on dsfield
+ run_cmd "$IP -6 route add 2001:db8:102::/64 dsfield 0x04 via 2001:db8:101::2"
+ log_test $? 2 "Reject route with dsfield"
+}
+
ipv6_route_test()
{
route_setup
ipv6_rt_add
ipv6_rt_replace
+ ipv6_rt_dsfield
route_cleanup
}
--
2.21.3
