ipv6 addrconf: Fix route lifetime setting in corner case.

Because of arithmetic overflow avoidance, the actual lifetime setting
(vs the value given by RA) did not increase monotonically around
0x7fffffff/HZ.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
YOSHIFUJI Hideaki 2008-05-19 16:54:29 -07:00 committed by David S. Miller
parent 44dc19c829
commit a3264435b4

View File

@ -475,7 +475,7 @@ int rt6_route_rcv(struct net_device *dev, u8 *opt, int len,
lifetime = ntohl(rinfo->lifetime);
if (lifetime == 0xffffffff) {
/* infinity */
} else if (lifetime > 0x7fffffff/HZ) {
} else if (lifetime > 0x7fffffff/HZ - 1) {
/* Avoid arithmetic overflow */
lifetime = 0x7fffffff/HZ - 1;
}