From 0e100f485fe38667187f17525f1ed7d66c788c8f Mon Sep 17 00:00:00 2001 From: Xin Long Date: Mon, 30 Jan 2023 11:25:33 -0500 Subject: [PATCH] sctp: do not check hb_timer.expires when resetting hb_timer [ Upstream commit 8f35ae17ef565a605de5f409e04bcd49a55d7646 ] It tries to avoid the frequently hb_timer refresh in commit 2b4aba5b269d ("sctp: avoid refreshing heartbeat timer too often"), and it only allows mod_timer when the new expires is after hb_timer.expires. It means even a much shorter interval for hb timer gets applied, it will have to wait until the current hb timer to time out. In sctp_do_8_2_transport_strike(), when a transport enters PF state, it expects to update the hb timer to resend a heartbeat every rto after calling sctp_transport_reset_hb_timer(), which will not work as the change mentioned above. The frequently hb_timer refresh was caused by sctp_transport_reset_timers() called in sctp_outq_flush() and it was already removed in the commit above. So we don't have to check hb_timer.expires when resetting hb_timer as it is now not called very often. Fixes: 2b4aba5b269d ("sctp: avoid refreshing heartbeat timer too often") Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Link: https://lore.kernel.org/r/d958c06985713ec84049a2d5664879802710179a.1675095933.git.lucien.xin@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- net/sctp/transport.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/net/sctp/transport.c b/net/sctp/transport.c index f8fd98784977a..b3f1a91e9a079 100644 --- a/net/sctp/transport.c +++ b/net/sctp/transport.c @@ -196,9 +196,7 @@ void sctp_transport_reset_hb_timer(struct sctp_transport *transport) /* When a data chunk is sent, reset the heartbeat interval. */ expires = jiffies + sctp_transport_timeout(transport); - if ((time_before(transport->hb_timer.expires, expires) || - !timer_pending(&transport->hb_timer)) && - !mod_timer(&transport->hb_timer, + if (!mod_timer(&transport->hb_timer, expires + prandom_u32_max(transport->rto))) sctp_transport_hold(transport); } -- 2.39.5