diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2021-04-23 11:17:07 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-04-23 14:06:32 -0700 |
| commit | 987858e5d026d355535b34f17c6ceeb1d71ccf75 (patch) | |
| tree | 4e0f78464b3da95b115d4f74aac0d2ee5dd00c4b /net | |
| parent | d976092ce1b04d634d408f475224347cfae81201 (diff) | |
| download | linux-987858e5d026d355535b34f17c6ceeb1d71ccf75.tar.bz2 | |
mptcp: ignore unsupported msg flags
Currently mptcp_sendmsg() fails with EOPNOTSUPP if the
user-space provides some unsupported flag. That is unexpected
and may foul existing applications migrated to MPTCP, which
expect a different behavior.
Change the mentioned function to silently ignore the unsupported
flags except MSG_FASTOPEN. This is the only flags currently not
supported by MPTCP with user-space visible side-effects.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/162
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/mptcp/protocol.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index ae08c563c712..a996dd5bb0c2 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -1614,9 +1614,13 @@ static int mptcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len) int ret = 0; long timeo; - if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL)) + /* we don't support FASTOPEN yet */ + if (msg->msg_flags & MSG_FASTOPEN) return -EOPNOTSUPP; + /* silently ignore everything else */ + msg->msg_flags &= MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL; + mptcp_lock_sock(sk, __mptcp_wmem_reserve(sk, min_t(size_t, 1 << 20, len))); timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); @@ -1951,9 +1955,6 @@ static int mptcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, if (unlikely(flags & MSG_ERRQUEUE)) return inet_recv_error(sk, msg, len, addr_len); - if (msg->msg_flags & ~(MSG_WAITALL | MSG_DONTWAIT)) - return -EOPNOTSUPP; - mptcp_lock_sock(sk, __mptcp_splice_receive_queue(sk)); if (unlikely(sk->sk_state == TCP_LISTEN)) { copied = -ENOTCONN; |