We always need to set subflow->data_avail after each tcp_read_sock() or mptcp_subflow_recv_lookup() may pick the wrong sock.

Squash-to: "mptcp: recvmsg() can drain data from multiple subflows" Signed-off-by: Paolo Abeni <pabeni(a)redhat.com&gt; --- net/mptcp/protocol.c | 18 +++++++++--------- net/mptcp/subflow.c | 1 + 2 files changed, 10 insertions(+), 9 deletions(-) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 3af5f121af9e..696f1d03a61d 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -473,6 +473,7 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, read_descriptor_t desc; struct socket *ssock; struct tcp_sock *tp; + bool done = false; struct sock *ssk; int copied = 0; int target; @@ -498,7 +499,7 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, len = min_t(size_t, len, INT_MAX); target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); - while (copied < len) { + while (!done) { u32 map_remaining; int bytes_read; @@ -515,7 +516,7 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, tp = tcp_sk(ssk); lock_sock(ssk); - while (mptcp_subflow_data_available(ssk)) { + while (mptcp_subflow_data_available(ssk) && !done) { /* try to read as much data as available */ map_remaining = subflow->map_data_len - mptcp_subflow_get_map_offset(subflow); @@ -526,8 +527,8 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, if (bytes_read < 0) { if (!copied) copied = bytes_read; - release_sock(ssk); - goto out; + done = true; + continue; } pr_debug("msk ack_seq=%llx -> %llx", msk->ack_seq, @@ -535,13 +536,13 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, msk->ack_seq += bytes_read; copied += bytes_read; if (copied >= len) { - release_sock(ssk); - goto out; + done = true; + continue; } if (tp->urg_data && tp->urg_seq == tp->copied_seq) { pr_err("Urgent data present, cannot proceed"); - release_sock(ssk); - goto out; + done = true; + continue; } } release_sock(ssk); @@ -590,7 +591,6 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, mptcp_wait_data(sk, &timeo); } -out: release_sock(sk); return copied; } diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 7bae7c35ea6b..f08c4b713978 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -576,6 +576,7 @@ bool mptcp_subflow_data_available(struct sock *sk) } if (!subflow_check_data_avail(sk)) { + subflow->data_avail = 0; /* set EoF only there is no data available - we already spooled * all the pending skbs */ -- 2.21.0 _______________________________________________ mptcp mailing list -- mptcp(a)lists.01.org To unsubscribe send an email to mptcp-leave(a)lists.01.org