From: Jens Rosenboom <me@jayr.de>
Date: Thu, 25 Jun 2009 04:55:50 +0000 (+0000)
Subject: ipv6: avoid wraparound for expired preferred lifetime
X-Git-Tag: firefly_0821_release~13027^2~277
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a1faa69810b2af562b70b2a71c116c7d03575dd3;p=firefly-linux-kernel-4.4.55.git

ipv6: avoid wraparound for expired preferred lifetime

Avoid showing wrong high values when the preferred lifetime of an address
is expired.

Signed-off-by: Jens Rosenboom <me@jayr.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 8c1e86afbbf5..3883b4036a74 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -3362,7 +3362,10 @@ static int inet6_fill_ifaddr(struct sk_buff *skb, struct inet6_ifaddr *ifa,
 		valid = ifa->valid_lft;
 		if (preferred != INFINITY_LIFE_TIME) {
 			long tval = (jiffies - ifa->tstamp)/HZ;
-			preferred -= tval;
+			if (preferred > tval)
+				preferred -= tval;
+			else
+				preferred = 0;
 			if (valid != INFINITY_LIFE_TIME)
 				valid -= tval;
 		}