1 files changed, 48 insertions, 21 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index a55500cc0b29..9a852156a8f3 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -824,12 +824,13 @@ 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, age;
+	unsigned long tmp_prefered_lft, tmp_valid_lft, tmp_tstamp, age;
 	unsigned long regen_advance;
 	int tmp_plen;
 	int ret = 0;
 	int max_addresses;
 	u32 addr_flags;
+	unsigned long now = jiffies;
 
 	write_lock(&idev->lock);
 	if (ift) {
@@ -874,7 +875,7 @@ retry:
 		goto out;
 	}
 	memcpy(&addr.s6_addr[8], idev->rndid, 8);
-	age = (jiffies - ifp->tstamp) / HZ;
+	age = (now - ifp->tstamp) / HZ;
 	tmp_valid_lft = min_t(__u32,
 			      ifp->valid_lft,
 			      idev->cnf.temp_valid_lft + age);
@@ -884,7 +885,6 @@ retry:
 				 idev->cnf.max_desync_factor);
 	tmp_plen = ifp->prefix_len;
 	max_addresses = idev->cnf.max_addresses;
-	tmp_cstamp = ifp->cstamp;
 	tmp_tstamp = ifp->tstamp;
 	spin_unlock_bh(&ifp->lock);
 
@@ -929,7 +929,7 @@ retry:
 	ift->ifpub = ifp;
 	ift->valid_lft = tmp_valid_lft;
 	ift->prefered_lft = tmp_prefered_lft;
-	ift->cstamp = tmp_cstamp;
+	ift->cstamp = now;
 	ift->tstamp = tmp_tstamp;
 	spin_unlock_bh(&ift->lock);
 
@@ -1999,25 +1999,50 @@ ok:
 #ifdef CONFIG_IPV6_PRIVACY
 			read_lock_bh(&in6_dev->lock);
 			/* update all temporary addresses in the list */
-			list_for_each_entry(ift, &in6_dev->tempaddr_list, tmp_list) {
-				/*
-				 * When adjusting the lifetimes of an existing
-				 * temporary address, only lower the lifetimes.
-				 * Implementations must not increase the
-				 * lifetimes of an existing temporary address
-				 * when processing a Prefix Information Option.
-				 */
+			list_for_each_entry(ift, &in6_dev->tempaddr_list,
+					    tmp_list) {
+				int age, max_valid, max_prefered;
+
 				if (ifp != ift->ifpub)
 					continue;
 
+				/*
+				 * RFC 4941 section 3.3:
+				 * If a received option will extend the lifetime
+				 * of a public address, the lifetimes of
+				 * temporary addresses should be extended,
+				 * subject to the overall constraint that no
+				 * temporary addresses should ever remain
+				 * "valid" or "preferred" for a time longer than
+				 * (TEMP_VALID_LIFETIME) or
+				 * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR),
+				 * respectively.
+				 */
+				age = (now - ift->cstamp) / HZ;
+				max_valid = in6_dev->cnf.temp_valid_lft - age;
+				if (max_valid < 0)
+					max_valid = 0;
+
+				max_prefered = in6_dev->cnf.temp_prefered_lft -
+					       in6_dev->cnf.max_desync_factor -
+					       age;
+				if (max_prefered < 0)
+					max_prefered = 0;
+
+				if (valid_lft > max_valid)
+					valid_lft = max_valid;
+
+				if (prefered_lft > max_prefered)
+					prefered_lft = max_prefered;
+
 				spin_lock(&ift->lock);
 				flags = ift->flags;
-				if (ift->valid_lft > valid_lft &&
-				    ift->valid_lft - valid_lft > (jiffies - ift->tstamp) / HZ)
-					ift->valid_lft = valid_lft + (jiffies - ift->tstamp) / HZ;
-				if (ift->prefered_lft > prefered_lft &&
-				    ift->prefered_lft - prefered_lft > (jiffies - ift->tstamp) / HZ)
-					ift->prefered_lft = prefered_lft + (jiffies - ift->tstamp) / HZ;
+				ift->valid_lft = valid_lft;
+				ift->prefered_lft = prefered_lft;
+				ift->tstamp = now;
+				if (prefered_lft > 0)
+					ift->flags &= ~IFA_F_DEPRECATED;
+
 				spin_unlock(&ift->lock);
 				if (!(flags&IFA_F_TENTATIVE))
 					ipv6_ifa_notify(0, ift);
@@ -2025,9 +2050,11 @@ ok:
 
 			if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
 				/*
-				 * When a new public address is created as described in [ADDRCONF],
-				 * also create a new temporary address. Also create a temporary
-				 * address if it's enabled but no temporary address currently exists.
+				 * When a new public address is created as
+				 * described in [ADDRCONF], also create a new
+				 * temporary address. Also create a temporary
+				 * address if it's enabled but no temporary
+				 * address currently exists.
 				 */
 				read_unlock_bh(&in6_dev->lock);
 				ipv6_create_tempaddr(ifp, NULL);