This is a note to let you know that I've just added the patch titled
mptcp: fix bogus sendmsg() return code under pressure
to the 5.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mptcp-fix-bogus-sendmsg-return-code-under-pressure.patch
and it can be found in the queue-5.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Mon 10 Aug 2020 02:00:10 PM CEST
From: Paolo Abeni <pabeni@xxxxxxxxxx>
Date: Mon, 3 Aug 2020 18:40:39 +0200
Subject: mptcp: fix bogus sendmsg() return code under pressure
From: Paolo Abeni <pabeni@xxxxxxxxxx>
[ Upstream commit 8555c6bfd5fddb1cf363d3cd157d70a1bb27f718 ]
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 <matthieu.baerts@xxxxxxxxxxxx>
Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/mptcp/protocol.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -802,7 +802,6 @@ fallback:
mptcp_set_timeout(sk, ssk);
if (copied) {
- ret = copied;
tcp_push(ssk, msg->msg_flags, mss_now, tcp_sk(ssk)->nonagle,
size_goal);
@@ -815,7 +814,7 @@ fallback:
release_sock(ssk);
out:
release_sock(sk);
- return ret;
+ return copied ? : ret;
}
static void mptcp_wait_data(struct sock *sk, long *timeo)
Patches currently in stable-queue which might be from pabeni@xxxxxxxxxx are
queue-5.7/mptcp-be-careful-on-subflow-creation.patch
queue-5.7/mptcp-fix-bogus-sendmsg-return-code-under-pressure.patch
