ipv6: Clamp reported valid_lft to a minimum of 0
Since addresses are only revalidated every 2 minutes, the reported
valid_lft can underflow shortly before the address is deleted.
Clamp it to a minimum of 0, as for prefered_lft.
Reported-by: Piotr Lewandowski <piotr.lewandowski@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index c20a7c2..51a273f 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -3495,8 +3495,12 @@
preferred -= tval;
else
preferred = 0;
- if (valid != INFINITY_LIFE_TIME)
- valid -= tval;
+ if (valid != INFINITY_LIFE_TIME) {
+ if (valid > tval)
+ valid -= tval;
+ else
+ valid = 0;
+ }
}
} else {
preferred = INFINITY_LIFE_TIME;