3 files changed, 50 insertions, 22 deletions

diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index 582e4ae70753..cbc6bb0a6838 100644
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h
@@ -8,7 +8,7 @@
 
 #define TEMP_VALID_LIFETIME             (7*86400)
 #define TEMP_PREFERRED_LIFETIME         (86400)
-#define REGEN_MAX_RETRY                 (5)
+#define REGEN_MAX_RETRY                 (3)
 #define MAX_DESYNC_FACTOR               (600)
 
 #define ADDR_CHECK_FREQUENCY            (120*HZ)
diff --git a/include/net/if_inet6.h b/include/net/if_inet6.h
index 11cf373970a9..51a7031b4aa3 100644
--- a/include/net/if_inet6.h
+++ b/include/net/if_inet6.h
@@ -41,6 +41,7 @@ struct inet6_ifaddr {
         struct in6_addr         addr;
         __u32                   prefix_len;
         
+        /* In seconds, relative to tstamp. Expiry is at tstamp + HZ * lft. */
         __u32                   valid_lft;
         __u32                   prefered_lft;
         atomic_t                refcnt;
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);