5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Matthieu Baerts (NGI0) matttbe@kernel.org
commit 2a1f596ebb23eadc0f9b95a8012e18ef76295fc8 upstream.
The 'mptcp_subflow_context' structure has two items related to the backup flags:
- 'backup': the subflow has been marked as backup by the other peer
- 'request_bkup': the backup flag has been set by the host
Looking only at the 'backup' flag can make sense in some cases, but it is not the behaviour of the default packet scheduler when selecting paths.
As explained in the commit b6a66e521a20 ("mptcp: sched: check both directions for backup"), the packet scheduler should look at both flags, because that was the behaviour from the beginning: the 'backup' flag was set by accident instead of the 'request_bkup' one. Now that the latter has been fixed, get_retrans() needs to be adapted as well.
Fixes: b6a66e521a20 ("mptcp: sched: check both directions for backup") Cc: stable@vger.kernel.org Reviewed-by: Mat Martineau martineau@kernel.org Signed-off-by: Matthieu Baerts (NGI0) matttbe@kernel.org Link: https://patch.msgid.link/20240826-net-mptcp-close-extra-sf-fin-v1-3-905199fe... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/mptcp/protocol.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2213,7 +2213,7 @@ static struct sock *mptcp_subflow_get_re continue; }
- if (subflow->backup) { + if (subflow->backup || subflow->request_bkup) { if (!backup) backup = ssk; continue;