diff options
| author | Jakub Sitnicki <jakub@cloudflare.com> | 2020-01-21 13:31:47 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-01-22 20:30:20 +0100 |
| commit | 58c8db929db1c1d785a6f5d8f8692e5dbcc35e84 (patch) | |
| tree | 555b6341eafcee8b16cb7d6a8f59701582085f50 | |
| parent | d0f418516022c32ecceaf4275423e5bd3f8743a9 (diff) | |
net, sk_msg: Don't check if sock is locked when tearing down psock
As John Fastabend reports [0], psock state tear-down can happen on receive
path *after* unlocking the socket, if the only other psock user, that is
sockmap or sockhash, releases its psock reference before tcp_bpf_recvmsg
does so:
tcp_bpf_recvmsg()
psock = sk_psock_get(sk) <- refcnt 2
lock_sock(sk);
...
sock_map_free() <- refcnt 1
release_sock(sk)
sk_psock_put() <- refcnt 0
Remove the lockdep check for socket lock in psock tear-down that got
introduced in 7e81a3530206 ("bpf: Sockmap, ensure sock lock held during
tear down").
[0] https://lore.kernel.org/netdev/5e25dc995d7d_74082aaee6e465b441@john-XPS-13-9370.notmuch/
Fixes: 7e81a3530206 ("bpf: Sockmap, ensure sock lock held during tear down")
Reported-by: syzbot+d73682fcf7fee6982fe3@syzkaller.appspotmail.com
Suggested-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/core/skmsg.c | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/net/core/skmsg.c b/net/core/skmsg.c index 3866d7e20c07..ded2d5227678 100644 --- a/net/core/skmsg.c +++ b/net/core/skmsg.c @@ -594,8 +594,6 @@ EXPORT_SYMBOL_GPL(sk_psock_destroy); void sk_psock_drop(struct sock *sk, struct sk_psock *psock) { - sock_owned_by_me(sk); - sk_psock_cork_free(psock); sk_psock_zap_ingress(psock); |