From 69800e516e968fa1cf9202b872dc86515eeeebe6 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Fri, 30 Sep 2022 08:59:31 -0700 Subject: mptcp: propagate fastclose error When an mptcp socket is closed due to an incoming FASTCLOSE option, so specific sk_err is set and later syscall will fail usually with EPIPE. Align the current fastclose error handling with TCP reset, properly setting the socket error according to the current msk state and propagating such error. Additionally sendmsg() is currently not handling properly the sk_err, always returning EPIPE. Reviewed-by: Matthieu Baerts Reviewed-by: Mat Martineau Signed-off-by: Paolo Abeni Signed-off-by: Mat Martineau Signed-off-by: David S. Miller --- net/mptcp/protocol.c | 47 ++++++++++++++++++++++++++++++++++++----------- 1 file changed, 36 insertions(+), 11 deletions(-) (limited to 'net') diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 760404b15cd0..cad0346c9281 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -1707,7 +1707,7 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) goto out; } else if (ret) { release_sock(ssk); - goto out; + goto do_error; } release_sock(ssk); } @@ -1717,9 +1717,13 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) if ((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) { ret = sk_stream_wait_connect(sk, &timeo); if (ret) - goto out; + goto do_error; } + ret = -EPIPE; + if (unlikely(sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))) + goto do_error; + pfrag = sk_page_frag(sk); while (msg_data_left(msg)) { @@ -1728,11 +1732,6 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) bool dfrag_collapsed; size_t psize, offset; - if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) { - ret = -EPIPE; - goto out; - } - /* reuse tail pfrag, if possible, or carve a new one from the * page allocator */ @@ -1764,7 +1763,7 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) if (copy_page_from_iter(dfrag->page, offset, psize, &msg->msg_iter) != psize) { ret = -EFAULT; - goto out; + goto do_error; } /* data successfully copied into the write queue */ @@ -1796,7 +1795,7 @@ wait_for_memory: __mptcp_push_pending(sk, msg->msg_flags); ret = sk_stream_wait_memory(sk, &timeo); if (ret) - goto out; + goto do_error; } if (copied) @@ -1804,7 +1803,14 @@ wait_for_memory: out: release_sock(sk); - return copied ? : ret; + return copied; + +do_error: + if (copied) + goto out; + + copied = sk_stream_error(sk, msg->msg_flags, ret); + goto out; } static int __mptcp_recvmsg_mskq(struct mptcp_sock *msk, @@ -2441,12 +2447,31 @@ static void mptcp_check_fastclose(struct mptcp_sock *msk) unlock_sock_fast(tcp_sk, slow); } + /* Mirror the tcp_reset() error propagation */ + switch (sk->sk_state) { + case TCP_SYN_SENT: + sk->sk_err = ECONNREFUSED; + break; + case TCP_CLOSE_WAIT: + sk->sk_err = EPIPE; + break; + case TCP_CLOSE: + return; + default: + sk->sk_err = ECONNRESET; + } + inet_sk_state_store(sk, TCP_CLOSE); sk->sk_shutdown = SHUTDOWN_MASK; smp_mb__before_atomic(); /* SHUTDOWN must be visible first */ set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &msk->flags); - mptcp_close_wake_up(sk); + /* the calling mptcp_worker will properly destroy the socket */ + if (sock_flag(sk, SOCK_DEAD)) + return; + + sk->sk_state_change(sk); + sk_error_report(sk); } static void __mptcp_retrans(struct sock *sk) -- cgit v1.2.3