From 59299aa1028fce051adbd25aaff7c387b865cd6d Mon Sep 17 00:00:00 2001
From: Marc Dionne <marc.dionne@auristor.com>
Date: Fri, 30 Mar 2018 21:04:44 +0100
Subject: [PATCH] rxrpc: Fix resend event time calculation
Commit a158bdd3 ("rxrpc: Fix call timeouts") reworked the time calculation
for the next resend event. For this calculation, "oldest" will be before
"now", so ktime_sub(oldest, now) will yield a negative value. When passed
to nsecs_to_jiffies which expects an unsigned value, the end result will be
a very large value, and a resend event scheduled far into the future. This
could cause calls to stall if some packets were lost.
Fix by ordering the arguments to ktime_sub correctly.
Fixes: a158bdd3247b ("rxrpc: Fix call timeouts")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
---
net/rxrpc/call_event.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/rxrpc/call_event.c b/net/rxrpc/call_event.c
index 3dee89c7a06e..6e0d788b4dc4 100644
--- a/net/rxrpc/call_event.c
+++ b/net/rxrpc/call_event.c
@@ -226,7 +226,7 @@ static void rxrpc_resend(struct rxrpc_call *call, unsigned long now_j)
ktime_to_ns(ktime_sub(skb->tstamp, max_age)));
}
- resend_at = nsecs_to_jiffies(ktime_to_ns(ktime_sub(oldest, now)));
+ resend_at = nsecs_to_jiffies(ktime_to_ns(ktime_sub(now, oldest)));
resend_at += jiffies + rxrpc_resend_timeout;
WRITE_ONCE(call->resend_at, resend_at);