diff options
| -rw-r--r-- | net/mptcp/protocol.c | 50 |
1 files changed, 46 insertions, 4 deletions
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 1833bc1f4a43..4cf88e3d5121 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -57,10 +57,43 @@ static bool __mptcp_needs_tcp_fallback(const struct mptcp_sock *msk) return msk->first && !sk_is_mptcp(msk->first); } +static struct socket *mptcp_is_tcpsk(struct sock *sk) +{ + struct socket *sock = sk->sk_socket; + + if (sock->sk != sk) + return NULL; + + if (unlikely(sk->sk_prot == &tcp_prot)) { + /* we are being invoked after mptcp_accept() has + * accepted a non-mp-capable flow: sk is a tcp_sk, + * not an mptcp one. + * + * Hand the socket over to tcp so all further socket ops + * bypass mptcp. + */ + sock->ops = &inet_stream_ops; + return sock; +#if IS_ENABLED(CONFIG_MPTCP_IPV6) + } else if (unlikely(sk->sk_prot == &tcpv6_prot)) { + sock->ops = &inet6_stream_ops; + return sock; +#endif + } + + return NULL; +} + static struct socket *__mptcp_tcp_fallback(struct mptcp_sock *msk) { + struct socket *sock; + sock_owned_by_me((const struct sock *)msk); + sock = mptcp_is_tcpsk((struct sock *)msk); + if (unlikely(sock)) + return sock; + if (likely(!__mptcp_needs_tcp_fallback(msk))) return NULL; @@ -84,6 +117,10 @@ static struct socket *__mptcp_socket_create(struct mptcp_sock *msk, int state) struct socket *ssock; int err; + ssock = __mptcp_tcp_fallback(msk); + if (unlikely(ssock)) + return ssock; + ssock = __mptcp_nmpc_socket(msk); if (ssock) goto set_state; @@ -1752,7 +1789,9 @@ static __poll_t mptcp_poll(struct file *file, struct socket *sock, msk = mptcp_sk(sk); lock_sock(sk); - ssock = __mptcp_nmpc_socket(msk); + ssock = __mptcp_tcp_fallback(msk); + if (!ssock) + ssock = __mptcp_nmpc_socket(msk); if (ssock) { mask = ssock->ops->poll(file, ssock, wait); release_sock(sk); @@ -1762,9 +1801,6 @@ static __poll_t mptcp_poll(struct file *file, struct socket *sock, release_sock(sk); sock_poll_wait(file, sock, wait); lock_sock(sk); - ssock = __mptcp_tcp_fallback(msk); - if (unlikely(ssock)) - return ssock->ops->poll(file, ssock, NULL); if (test_bit(MPTCP_DATA_READY, &msk->flags)) mask = EPOLLIN | EPOLLRDNORM; @@ -1783,11 +1819,17 @@ static int mptcp_shutdown(struct socket *sock, int how) { struct mptcp_sock *msk = mptcp_sk(sock->sk); struct mptcp_subflow_context *subflow; + struct socket *ssock; int ret = 0; pr_debug("sk=%p, how=%d", msk, how); lock_sock(sock->sk); + ssock = __mptcp_tcp_fallback(msk); + if (ssock) { + release_sock(sock->sk); + return inet_shutdown(ssock, how); + } if (how == SHUT_WR || how == SHUT_RDWR) inet_sk_state_store(sock->sk, TCP_FIN_WAIT1); |