ipv6: do not set routes if disable_ipv6 has been enabled
Do not allow setting ipv6 routes from userspace if disable_ipv6 has been
enabled. The issue can be triggered using the following reproducer:
- sysctl net.ipv6.conf.all.disable_ipv6=1
- ip -6 route add a:b:c:d::/64 dev em1
- ip -6 route show
a:b:c:d::/64 dev em1 metric 1024 pref medium
Fix it checking disable_ipv6 value in ip6_route_info_create routine
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index ba8d5df..e461ef1 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -2917,6 +2917,12 @@ static struct rt6_info *ip6_route_info_create(struct fib6_config *cfg,
if (!dev)
goto out;
+ if (idev->cnf.disable_ipv6) {
+ NL_SET_ERR_MSG(extack, "IPv6 is disabled on nexthop device");
+ err = -EACCES;
+ goto out;
+ }
+
if (!(dev->flags & IFF_UP)) {
NL_SET_ERR_MSG(extack, "Nexthop device is not up");
err = -ENETDOWN;