diff options
| author |   Eric Dumazet <edumazet@google.com> | 2025-02-05 15:51:18 +0000 |
|---|---|---|
| committer |   Jakub Kicinski <kuba@kernel.org> | 2025-02-06 16:14:15 -0800 |
| commit | 3c8ffcd248da34fc41e52a46e51505900115fc2a (patch) | |
| tree | ad7b64e8bb9bbcb3d092e770f1aa04a4eb0e6948 | |
| parent | flow_dissector: use RCU protection to fetch dev_net() (diff) | |
| download | wireguard-linux-3c8ffcd248da34fc41e52a46e51505900115fc2a.tar.xz wireguard-linux-3c8ffcd248da34fc41e52a46e51505900115fc2a.zip | |
ipv6: use RCU protection in ip6_default_advmss()
ip6_default_advmss() needs rcu protection to make
sure the net structure it reads does not disappear.
Fixes: 5578689a4e3c ("[NETNS][IPV6] route6 - make route6 per namespace")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250205155120.1676781-11-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/ipv6/route.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 78362822b907..ef2d23a1e3d5 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -3196,13 +3196,18 @@ static unsigned int ip6_default_advmss(const struct dst_entry *dst) { struct net_device *dev = dst->dev; unsigned int mtu = dst_mtu(dst); - struct net *net = dev_net(dev); + struct net *net; mtu -= sizeof(struct ipv6hdr) + sizeof(struct tcphdr); + rcu_read_lock(); + + net = dev_net_rcu(dev); if (mtu < net->ipv6.sysctl.ip6_rt_min_advmss) mtu = net->ipv6.sysctl.ip6_rt_min_advmss; + rcu_read_unlock(); + /* * Maximal non-jumbo IPv6 payload is IPV6_MAXPLEN and * corresponding MSS is IPV6_MAXPLEN - tcp_header_size. |