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authorBenoit Boissinot <benoit.boissinot@ens-lyon.org>2008-04-02 00:01:35 -0700
committerDavid S. Miller <davem@davemloft.net>2008-04-02 00:01:35 -0700
commiteac55bf97094f6b64116426864cf4666ef7587bc (patch)
tree467776de93a7fdbb75904dbd702f7c417e18aa69
parentc6fbfac2e61c9a8617f64b93e8c990b8d864bce5 (diff)
downloadlinux-eac55bf97094f6b64116426864cf4666ef7587bc.tar.bz2
IPv6: do not create temporary adresses with too short preferred lifetime
From RFC341: A temporary address is created only if this calculated Preferred Lifetime is greater than REGEN_ADVANCE time units. In particular, an implementation must not create a temporary address with a zero Preferred Lifetime. Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org> Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--net/ipv6/addrconf.c16
1 files changed, 16 insertions, 0 deletions
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index e11f10eceffc..e7a1882db048 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -776,6 +776,7 @@ static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, struct inet6_ifaddr *i
struct inet6_dev *idev = ifp->idev;
struct in6_addr addr, *tmpaddr;
unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_cstamp, tmp_tstamp;
+ unsigned long regen_advance;
int tmp_plen;
int ret = 0;
int max_addresses;
@@ -836,8 +837,23 @@ retry:
tmp_tstamp = ifp->tstamp;
spin_unlock_bh(&ifp->lock);
+ regen_advance = idev->cnf.regen_max_retry *
+ idev->cnf.dad_transmits *
+ idev->nd_parms->retrans_time / HZ;
write_unlock(&idev->lock);
+ /* A temporary address is created only if this calculated Preferred
+ * Lifetime is greater than REGEN_ADVANCE time units. In particular,
+ * an implementation must not create a temporary address with a zero
+ * Preferred Lifetime.
+ */
+ if (tmp_prefered_lft <= regen_advance) {
+ in6_ifa_put(ifp);
+ in6_dev_put(idev);
+ ret = -1;
+ goto out;
+ }
+
addr_flags = IFA_F_TEMPORARY;
/* set in addrconf_prefix_rcv() */
if (ifp->flags & IFA_F_OPTIMISTIC)