diff options
| author | Jakub Sitnicki <jakub@cloudflare.com> | 2020-01-21 15:31:47 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-01-29 18:45:31 +0300 |
| commit | 5d001c4f74e0417c25e1da6fc861e8f9ee0ba290 (patch) | |
| tree | f2704049dc3f33d030fc52c3d33b139bac9c4136 /net/core | |
| parent | b2e061912c3ec2843e149208fc0160c2bed877cb (diff) | |
| download | linux-5d001c4f74e0417c25e1da6fc861e8f9ee0ba290.tar.xz | |
net, sk_msg: Don't check if sock is locked when tearing down psock
commit 58c8db929db1c1d785a6f5d8f8692e5dbcc35e84 upstream.
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/core')
| -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); |