2 files changed, 89 insertions, 13 deletions

diff --git a/include/net/route.h b/include/net/route.h
index 30d6cae3841a..dc102445ec47 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -207,6 +207,7 @@ extern int		ip_rt_dump(struct sk_buff *skb,  struct netlink_callback *cb);
 
 struct in_ifaddr;
 extern void fib_add_ifaddr(struct in_ifaddr *);
+extern void fib_del_ifaddr(struct in_ifaddr *, struct in_ifaddr *);
 
 static inline void ip_rt_put(struct rtable * rt)
 {
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index a373a259253c..02c3ba61884a 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -722,12 +722,17 @@ void fib_add_ifaddr(struct in_ifaddr *ifa)
         }
 }
 
-static void fib_del_ifaddr(struct in_ifaddr *ifa)
+/* Delete primary or secondary address.
+ * Optionally, on secondary address promotion consider the addresses
+ * from subnet iprim as deleted, even if they are in device list.
+ * In this case the secondary ifa can be in device list.
+ */
+void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim)
 {
         struct in_device *in_dev = ifa->ifa_dev;
         struct net_device *dev = in_dev->dev;
         struct in_ifaddr *ifa1;
-        struct in_ifaddr *prim = ifa;
+        struct in_ifaddr *prim = ifa, *prim1 = NULL;
         __be32 brd = ifa->ifa_address | ~ifa->ifa_mask;
         __be32 any = ifa->ifa_address & ifa->ifa_mask;
 #define LOCAL_OK        1
@@ -735,17 +740,26 @@ static void fib_del_ifaddr(struct in_ifaddr *ifa)
 #define BRD0_OK         4
 #define BRD1_OK         8
         unsigned ok = 0;
+        int subnet = 0;         /* Primary network */
+        int gone = 1;           /* Address is missing */
+        int same_prefsrc = 0;   /* Another primary with same IP */
 
-        if (!(ifa->ifa_flags & IFA_F_SECONDARY))
-                fib_magic(RTM_DELROUTE,
-                          dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
-                          any, ifa->ifa_prefixlen, prim);
-        else {
+        if (ifa->ifa_flags & IFA_F_SECONDARY) {
                 prim = inet_ifa_byprefix(in_dev, any, ifa->ifa_mask);
                 if (prim == NULL) {
                         printk(KERN_WARNING "fib_del_ifaddr: bug: prim == NULL\n");
                         return;
                 }
+                if (iprim && iprim != prim) {
+                        printk(KERN_WARNING "fib_del_ifaddr: bug: iprim != prim\n");
+                        return;
+                }
+        } else if (!ipv4_is_zeronet(any) &&
+                   (any != ifa->ifa_local || ifa->ifa_prefixlen < 32)) {
+                fib_magic(RTM_DELROUTE,
+                          dev->flags & IFF_LOOPBACK ? RTN_LOCAL : RTN_UNICAST,
+                          any, ifa->ifa_prefixlen, prim);
+                subnet = 1;
         }
 
         /* Deletion is more complicated than add.
@@ -755,6 +769,49 @@ static void fib_del_ifaddr(struct in_ifaddr *ifa)
          */
 
         for (ifa1 = in_dev->ifa_list; ifa1; ifa1 = ifa1->ifa_next) {
+                if (ifa1 == ifa) {
+                        /* promotion, keep the IP */
+                        gone = 0;
+                        continue;
+                }
+                /* Ignore IFAs from our subnet */
+                if (iprim && ifa1->ifa_mask == iprim->ifa_mask &&
+                    inet_ifa_match(ifa1->ifa_address, iprim))
+                        continue;
+
+                /* Ignore ifa1 if it uses different primary IP (prefsrc) */
+                if (ifa1->ifa_flags & IFA_F_SECONDARY) {
+                        /* Another address from our subnet? */
+                        if (ifa1->ifa_mask == prim->ifa_mask &&
+                            inet_ifa_match(ifa1->ifa_address, prim))
+                                prim1 = prim;
+                        else {
+                                /* We reached the secondaries, so
+                                 * same_prefsrc should be determined.
+                                 */
+                                if (!same_prefsrc)
+                                        continue;
+                                /* Search new prim1 if ifa1 is not
+                                 * using the current prim1
+                                 */
+                                if (!prim1 ||
+                                    ifa1->ifa_mask != prim1->ifa_mask ||
+                                    !inet_ifa_match(ifa1->ifa_address, prim1))
+                                        prim1 = inet_ifa_byprefix(in_dev,
+                                                        ifa1->ifa_address,
+                                                        ifa1->ifa_mask);
+                                if (!prim1)
+                                        continue;
+                                if (prim1->ifa_local != prim->ifa_local)
+                                        continue;
+                        }
+                } else {
+                        if (prim->ifa_local != ifa1->ifa_local)
+                                continue;
+                        prim1 = ifa1;
+                        if (prim != prim1)
+                                same_prefsrc = 1;
+                }
                 if (ifa->ifa_local == ifa1->ifa_local)
                         ok |= LOCAL_OK;
                 if (ifa->ifa_broadcast == ifa1->ifa_broadcast)
@@ -763,19 +820,37 @@ static void fib_del_ifaddr(struct in_ifaddr *ifa)
                         ok |= BRD1_OK;
                 if (any == ifa1->ifa_broadcast)
                         ok |= BRD0_OK;
+                /* primary has network specific broadcasts */
+                if (prim1 == ifa1 && ifa1->ifa_prefixlen < 31) {
+                        __be32 brd1 = ifa1->ifa_address | ~ifa1->ifa_mask;
+                        __be32 any1 = ifa1->ifa_address & ifa1->ifa_mask;
+
+                        if (!ipv4_is_zeronet(any1)) {
+                                if (ifa->ifa_broadcast == brd1 ||
+                                    ifa->ifa_broadcast == any1)
+                                        ok |= BRD_OK;
+                                if (brd == brd1 || brd == any1)
+                                        ok |= BRD1_OK;
+                                if (any == brd1 || any == any1)
+                                        ok |= BRD0_OK;
+                        }
+                }
         }
 
         if (!(ok & BRD_OK))
                 fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
-        if (!(ok & BRD1_OK))
-                fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim);
-        if (!(ok & BRD0_OK))
-                fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim);
+        if (subnet && ifa->ifa_prefixlen < 31) {
+                if (!(ok & BRD1_OK))
+                        fib_magic(RTM_DELROUTE, RTN_BROADCAST, brd, 32, prim);
+                if (!(ok & BRD0_OK))
+                        fib_magic(RTM_DELROUTE, RTN_BROADCAST, any, 32, prim);
+        }
         if (!(ok & LOCAL_OK)) {
                 fib_magic(RTM_DELROUTE, RTN_LOCAL, ifa->ifa_local, 32, prim);
 
                 /* Check, that this local address finally disappeared. */
-                if (inet_addr_type(dev_net(dev), ifa->ifa_local) != RTN_LOCAL) {
+                if (gone &&
+                    inet_addr_type(dev_net(dev), ifa->ifa_local) != RTN_LOCAL) {
                         /* And the last, but not the least thing.
                          * We must flush stray FIB entries.
                          *
@@ -896,7 +971,7 @@ static int fib_inetaddr_event(struct notifier_block *this, unsigned long event,
                 rt_cache_flush(dev_net(dev), -1);
                 break;
         case NETDEV_DOWN:
-                fib_del_ifaddr(ifa);
+                fib_del_ifaddr(ifa, NULL);
                 fib_update_nh_saddrs(dev);
                 if (ifa->ifa_dev->ifa_list == NULL) {
                         /* Last address was deleted from this interface.