From 4af00f4cc1ba34da4654ac31830843cae871642d Mon Sep 17 00:00:00 2001 From: Jon Maloy Date: Thu, 11 Oct 2018 22:02:29 +0200 Subject: [PATCH] tipc: initialize broadcast link stale counter correctly In the commit referred to below we added link tolerance as an additional criteria for declaring broadcast transmission "stale" and resetting the unicast links to the affected node. Unfortunately, this 'improvement' introduced two bugs, which each and one alone cause only limited problems, but combined lead to seemingly stochastic unicast link resets, depending on the amount of broadcast traffic transmitted. The first issue, a missing initialization of the 'tolerance' field of the receiver broadcast link, was recently fixed by commit 047491ea334a ("tipc: set link tolerance correctly in broadcast link"). Ths second issue, where we omit to reset the 'stale_cnt' field of the same link after a 'stale' period is over, leads to this counter accumulating over time, and in the absence of the 'tolerance' criteria leads to the above described symptoms. This commit adds the missing initialization. Fixes: a4dc70d46cf1 ("tipc: extend link reset criteria for stale packet retransmission") Signed-off-by: Jon Maloy Acked-by: Ying Xue Signed-off-by: David S. Miller --- net/tipc/link.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/tipc/link.c b/net/tipc/link.c index f6552e4f4b43..201c3b5bc96b 100644 --- a/net/tipc/link.c +++ b/net/tipc/link.c @@ -1041,6 +1041,7 @@ static int tipc_link_retrans(struct tipc_link *l, struct tipc_link *r, if (r->last_retransm != buf_seqno(skb)) { r->last_retransm = buf_seqno(skb); r->stale_limit = jiffies + msecs_to_jiffies(r->tolerance); + r->stale_cnt = 0; } else if (++r->stale_cnt > 99 && time_after(jiffies, r->stale_limit)) { link_retransmit_failure(l, skb); if (link_is_bc_sndlink(l)) -- 2.30.2