From 8555c6bfd5fddb1cf363d3cd157d70a1bb27f718 Mon Sep 17 00:00:00 2001 From: Paolo Abeni Date: Mon, 3 Aug 2020 18:40:39 +0200 Subject: mptcp: fix bogus sendmsg() return code under pressure In case of memory pressure, mptcp_sendmsg() may call sk_stream_wait_memory() after succesfully xmitting some bytes. If the latter fails we currently return to the user-space the error code, ignoring the succeful xmit. Address the issue always checking for the xmitted bytes before mptcp_sendmsg() completes. Fixes: f296234c98a8 ("mptcp: Add handling of incoming MP_JOIN requests") Reviewed-by: Matthieu Baerts Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller --- net/mptcp/protocol.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'net') diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 400824eabf73..8c1d1a595701 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -984,7 +984,6 @@ wait_for_sndbuf: mptcp_set_timeout(sk, ssk); if (copied) { - ret = copied; tcp_push(ssk, msg->msg_flags, mss_now, tcp_sk(ssk)->nonagle, size_goal); @@ -997,7 +996,7 @@ wait_for_sndbuf: release_sock(ssk); out: release_sock(sk); - return ret; + return copied ? : ret; } static void mptcp_wait_data(struct sock *sk, long *timeo) -- cgit v1.2.3