[PATCH 6.6.y 3/3] mptcp: fix bad accounting in __mptcp_subflow_push_pending()

["Matthieu Baerts (NGI0)" <matttbe@kernel.org>]

From: Paolo Abeni <pabeni@redhat.com>

commit f3ef03357396d4b147d8e76c75fb612c2f264ffc upstream.

If __subflow_push_pending() errors out we should avoid updating the
copied byte counters, to avoid mismatch push call later on.

Fixes: 0fa1b3783a17 ("mptcp: use get_send wrapper")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20260917-net-mptcp-misc-fixes-7-3-rc4-v2-3-0cf5c72667c8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 net/mptcp/protocol.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 3c1ad8601fb2..cd76b2d742d3 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -1750,7 +1750,8 @@ static void __mptcp_subflow_push_pending(struct sock *sk, struct sock *ssk, bool
 			ret = __subflow_push_pending(sk, ssk, &info);
 			if (ret <= 0)
 				keep_pushing = false;
-			copied += ret;
+			else
+				copied += ret;
 		}
 
 		mptcp_for_each_subflow(msk, subflow) {
-- 
2.55.0