diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2019-02-21 11:19:42 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-03-19 13:11:55 +0100 |
| commit | 34bb9431e491c8739ce33e9a9964cb4275729cfb (patch) | |
| tree | a64a24fe0d4096c657b839fe70713d6047418a19 /net | |
| parent | 1f1cdcc0ccd9e0660ce881c9c0b16e85d81fd44a (diff) | |
ipv6: route: enforce RCU protection in ip6_route_check_nh_onlink()
[ Upstream commit bf1dc8bad1d42287164d216d8efb51c5cd381b18 ]
We need a RCU critical section around rt6_info->from deference, and
proper annotation.
Fixes: 4ed591c8ab44 ("net/ipv6: Allow onlink routes to have a device mismatch if it is the default route")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv6/route.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 7e21797d7ae8..603488cf132d 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2752,20 +2752,24 @@ static int ip6_route_check_nh_onlink(struct net *net, u32 tbid = l3mdev_fib_table(dev) ? : RT_TABLE_MAIN; const struct in6_addr *gw_addr = &cfg->fc_gateway; u32 flags = RTF_LOCAL | RTF_ANYCAST | RTF_REJECT; + struct fib6_info *from; struct rt6_info *grt; int err; err = 0; grt = ip6_nh_lookup_table(net, cfg, gw_addr, tbid, 0); if (grt) { + rcu_read_lock(); + from = rcu_dereference(grt->from); if (!grt->dst.error && /* ignore match if it is the default route */ - grt->from && !ipv6_addr_any(&grt->from->fib6_dst.addr) && + from && !ipv6_addr_any(&from->fib6_dst.addr) && (grt->rt6i_flags & flags || dev != grt->dst.dev)) { NL_SET_ERR_MSG(extack, "Nexthop has invalid gateway or device mismatch"); err = -EINVAL; } + rcu_read_unlock(); ip6_rt_put(grt); } |