sit: fix prefix length of ll and v4mapped addresses

When the local IPv4 endpoint is wilcard (0.0.0.0), the prefix length is
correctly set, ie 64 if the address is a link local one or 96 if the address is
a v4 mapped one.
But when the local endpoint is specified, the prefix length is set to 128 for
both kind of address. This patch fix this wrong prefix length.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 7 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 542d09561ed6..27fedc3e4449 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2528,7 +2528,7 @@ static void sit_add_v4_addrs(struct inet6_dev *idev)
         struct in6_addr addr;
         struct net_device *dev;
         struct net *net = dev_net(idev->dev);
-        int scope;
+        int scope, plen;
 
         ASSERT_RTNL();
 
@@ -2538,12 +2538,14 @@ static void sit_add_v4_addrs(struct inet6_dev *idev)
         if (idev->dev->flags&IFF_POINTOPOINT) {
                 addr.s6_addr32[0] = htonl(0xfe800000);
                 scope = IFA_LINK;
+                plen = 64;
         } else {
                 scope = IPV6_ADDR_COMPATv4;
+                plen = 96;
         }
 
         if (addr.s6_addr32[3]) {
-                add_addr(idev, &addr, 128, scope);
+                add_addr(idev, &addr, plen, scope);
                 return;
         }
 
@@ -2555,7 +2557,6 @@ static void sit_add_v4_addrs(struct inet6_dev *idev)
                         int flag = scope;
 
                         for (ifa = in_dev->ifa_list; ifa; ifa = ifa->ifa_next) {
-                                int plen;
 
                                 addr.s6_addr32[3] = ifa->ifa_local;
 
@@ -2566,10 +2567,6 @@ static void sit_add_v4_addrs(struct inet6_dev *idev)
                                                 continue;
                                         flag |= IFA_HOST;
                                 }
-                                if (idev->dev->flags&IFF_POINTOPOINT)
-                                        plen = 64;
-                                else
-                                        plen = 96;
 
                                 add_addr(idev, &addr, plen, flag);
                         }