1 files changed, 3 insertions, 0 deletions

diff --git a/net/ipv4/tcp_illinois.c b/net/ipv4/tcp_illinois.c
index 4adc47c55351..b2b2256d3b84 100644
--- a/net/ipv4/tcp_illinois.c
+++ b/net/ipv4/tcp_illinois.c
@@ -90,6 +90,9 @@ static void tcp_illinois_acked(struct sock *sk, u32 pkts_acked, ktime_t last)
 
         ca->acked = pkts_acked;
 
+        if (ktime_equal(last, net_invalid_timestamp()))
+                return;
+
         rtt = ktime_to_us(net_timedelta(last));
 
         /* ignore bogus values, this prevents wraparound in alpha math */