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| author | Cong Wang <cong.wang@bytedance.com> | 2024-08-22 11:25:44 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-08-26 09:55:40 -0700 |
| commit | 1461f5a3d810869e182f1d11caaac7dee0458ff7 (patch) | |
| tree | 41bf49633545c056b7357227ad56384db30b1c70 /net/l2tp | |
| parent | 7888173eb18063c15e10d099310a58ab8c3a4b44 (diff) | |
| download | lwn-1461f5a3d810869e182f1d11caaac7dee0458ff7.tar.gz lwn-1461f5a3d810869e182f1d11caaac7dee0458ff7.zip | |
l2tp: avoid overriding sk->sk_user_data
Although commit 4a4cd70369f1 ("l2tp: don't set sk_user_data in tunnel socket")
removed sk->sk_user_data usage, setup_udp_tunnel_sock() still touches
sk->sk_user_data, this conflicts with sockmap which also leverages
sk->sk_user_data to save psock.
Restore this sk->sk_user_data check to avoid such conflicts.
Fixes: 4a4cd70369f1 ("l2tp: don't set sk_user_data in tunnel socket")
Reported-by: syzbot+8dbe3133b840c470da0e@syzkaller.appspotmail.com
Cc: Tom Parkin <tparkin@katalix.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Tested-by: James Chapman <jchapman@katalix.com>
Reviewed-by: James Chapman <jchapman@katalix.com>
Link: https://patch.msgid.link/20240822182544.378169-1-xiyou.wangcong@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/l2tp')
| -rw-r--r-- | net/l2tp/l2tp_core.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c index af87c781d6a6..df73c35363cb 100644 --- a/net/l2tp/l2tp_core.c +++ b/net/l2tp/l2tp_core.c @@ -1620,6 +1620,9 @@ static int l2tp_validate_socket(const struct sock *sk, const struct net *net, (encap == L2TP_ENCAPTYPE_IP && sk->sk_protocol != IPPROTO_L2TP)) return -EPROTONOSUPPORT; + if (encap == L2TP_ENCAPTYPE_UDP && sk->sk_user_data) + return -EBUSY; + tunnel = l2tp_sk_to_tunnel(sk); if (tunnel) { l2tp_tunnel_put(tunnel); |