diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2023-02-07 14:04:14 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2023-02-08 09:39:34 +0000 |
| commit | 21e43569685de4ad773fb060c11a15f3fd5e7ac4 (patch) | |
| tree | 9b0b464844a8dd4b1d42f9806ba76ee2eb718e35 /net | |
| parent | d4e85922e3e7ef2071f91f65e61629b60f3a9cf4 (diff) | |
mptcp: fix locking for setsockopt corner-case
We need to call the __mptcp_nmpc_socket(), and later subflow socket
access under the msk socket lock, or e.g. a racing connect() could
change the socket status under the hood, with unexpected results.
Fixes: 54635bd04701 ("mptcp: add TCP_FASTOPEN_CONNECT socket option")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/mptcp/sockopt.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c index d4b1e6ec1b36..7f2c3727ab23 100644 --- a/net/mptcp/sockopt.c +++ b/net/mptcp/sockopt.c @@ -760,14 +760,21 @@ static int mptcp_setsockopt_v4(struct mptcp_sock *msk, int optname, static int mptcp_setsockopt_first_sf_only(struct mptcp_sock *msk, int level, int optname, sockptr_t optval, unsigned int optlen) { + struct sock *sk = (struct sock *)msk; struct socket *sock; + int ret = -EINVAL; /* Limit to first subflow, before the connection establishment */ + lock_sock(sk); sock = __mptcp_nmpc_socket(msk); if (!sock) - return -EINVAL; + goto unlock; - return tcp_setsockopt(sock->sk, level, optname, optval, optlen); + ret = tcp_setsockopt(sock->sk, level, optname, optval, optlen); + +unlock: + release_sock(sk); + return ret; } static int mptcp_setsockopt_sol_tcp(struct mptcp_sock *msk, int optname, |