Commit 59299aa1 authored Mar 30, 2018 by Marc Dionne Committed by David Howells Mar 30, 2018

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: a158bdd3 ("rxrpc: Fix call timeouts")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>

parent 57b0c9d4

net/rxrpc/call_event.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -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);

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