1 files changed, 29 insertions, 1 deletions

diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index 6d85800daeb7..5345b0bee6df 100644
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -64,6 +64,8 @@
 #include <net/rtnetlink.h>
 #include <net/net_namespace.h>
 
+#include "fib_lookup.h"
+
 static struct ipv4_devconf ipv4_devconf = {
         .data = {
                 [IPV4_DEVCONF_ACCEPT_REDIRECTS - 1] = 1,
@@ -151,6 +153,20 @@ struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref)
                         break;
                 }
         }
+        if (!result) {
+                struct flowi4 fl4 = { .daddr = addr };
+                struct fib_result res = { 0 };
+                struct fib_table *local;
+
+                /* Fallback to FIB local table so that communication
+                 * over loopback subnets work.
+                 */
+                local = fib_get_table(net, RT_TABLE_LOCAL);
+                if (local &&
+                    !fib_table_lookup(local, &fl4, &res, FIB_LOOKUP_NOREF) &&
+                    res.type == RTN_LOCAL)
+                        result = FIB_RES_DEV(res);
+        }
         if (result && devref)
                 dev_hold(result);
         rcu_read_unlock();
@@ -345,6 +361,17 @@ static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
                 }
         }
 
+        /* On promotion all secondaries from subnet are changing
+         * the primary IP, we must remove all their routes silently
+         * and later to add them back with new prefsrc. Do this
+         * while all addresses are on the device list.
+         */
+        for (ifa = promote; ifa; ifa = ifa->ifa_next) {
+                if (ifa1->ifa_mask == ifa->ifa_mask &&
+                    inet_ifa_match(ifa1->ifa_address, ifa))
+                        fib_del_ifaddr(ifa, ifa1);
+        }
+
         /* 2. Unlink it */
 
         *ifap = ifa1->ifa_next;
@@ -364,6 +391,7 @@ static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
         blocking_notifier_call_chain(&inetaddr_chain, NETDEV_DOWN, ifa1);
 
         if (promote) {
+                struct in_ifaddr *next_sec = promote->ifa_next;
 
                 if (prev_prom) {
                         prev_prom->ifa_next = promote->ifa_next;
@@ -375,7 +403,7 @@ static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
                 rtmsg_ifa(RTM_NEWADDR, promote, nlh, pid);
                 blocking_notifier_call_chain(&inetaddr_chain,
                                 NETDEV_UP, promote);
-                for (ifa = promote->ifa_next; ifa; ifa = ifa->ifa_next) {
+                for (ifa = next_sec; ifa; ifa = ifa->ifa_next) {
                         if (ifa1->ifa_mask != ifa->ifa_mask ||
                             !inet_ifa_match(ifa1->ifa_address, ifa))
                                         continue;