| Message ID | CAHPKR9KjB+6+WD9R4D81vZ6eFvcwgDJKgHFYvKxQQ2t_T7x9fg@mail.gmail.com |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
Balakumaran Kannan wrote: > IPv6 Routing table becomes broken once we do ifdown, ifup of the loopback(lo) > interface. After down-up, routes of other interface's IPv6 addresses through > 'lo' are lost. > > IPv6 addresses assigned to all interfaces are routed through 'lo' for internal > communication. Once 'lo' is down, those routing entries are removed from > routing table. But those removed entries are not being re-created properly when > 'lo' is brought up. So IPv6 addresses of other interfaces becomes unreachable > from the same machine. Also this breaks communication with other machines > because of NDISC packet processing failure. > > This patch fixes this issue by reading all interface's IPv6 addresses and > adding them to IPv6 routing table while bringing up 'lo'. > > Patch is prepared for Linux-3.9.rc4 kernel. > > Signed-off-by: Balakumaran Kannan <Balakumaran.Kannan@ap.sony.com> > Signed-off-by: Maruthi Thotad <Maruthi.Thotad@ap.sm.sony.com> > --- > ==Testing== > Before applying the patch: > $ route -A inet6 > Kernel IPv6 routing table > Destination Next Hop Flag Met Ref Use If > 2000::20/128 :: U 256 0 0 eth0 > fe80::/64 :: U 256 0 0 eth0 > ::/0 :: !n -1 1 1 lo > ::1/128 :: Un 0 1 0 lo > 2000::20/128 :: Un 0 1 0 lo > fe80::xxxx:xxxx:xxxx:xxxx/128 :: Un 0 1 0 lo > ff00::/8 :: U 256 0 0 eth0 > ::/0 :: !n -1 1 1 lo > $ sudo ifdown lo > $ sudo ifup lo > $ route -A inet6 > Kernel IPv6 routing table > Destination Next Hop Flag Met Ref Use If > 2000::20/128 :: U 256 0 0 eth0 > fe80::/64 :: U 256 0 0 eth0 > ::/0 :: !n -1 1 1 lo > ::1/128 :: Un 0 1 0 lo > ff00::/8 :: U 256 0 0 eth0 > ::/0 :: !n -1 1 1 lo > $ > > After applying the patch: > $ route -A inet6 > Kernel IPv6 routing > table > Destination Next Hop Flag Met Ref Use If > 2000::20/128 :: U 256 0 0 eth0 > fe80::/64 :: U 256 0 0 eth0 > ::/0 :: !n -1 1 1 lo > ::1/128 :: Un 0 1 0 lo > 2000::20/128 :: Un 0 1 0 lo > fe80::xxxx:xxxx:xxxx:xxxx/128 :: Un 0 1 0 lo > ff00::/8 :: U 256 0 0 eth0 > ::/0 :: !n -1 1 1 lo > $ sudo ifdown lo > $ sudo ifup lo > $ route -A inet6 > Kernel IPv6 routing table > Destination Next Hop Flag Met Ref Use If > 2000::20/128 :: U 256 0 0 eth0 > fe80::/64 :: U 256 0 0 eth0 > ::/0 :: !n -1 1 1 lo > ::1/128 :: Un 0 1 0 lo > 2000::20/128 :: Un 0 1 0 lo > fe80::xxxx:xxxx:xxxx:xxxx/128 :: Un 0 1 0 lo > ff00::/8 :: U 256 0 0 eth0 > ::/0 :: !n -1 1 1 lo > $ > --- > --- linux-3.9-rc4/net/ipv6/addrconf.c.orig 2013-03-27 10:40:26.382569527 +0530 > +++ linux-3.9-rc4/net/ipv6/addrconf.c 2013-03-27 10:56:45.227354856 +0530 > @@ -2529,6 +2529,11 @@ static void sit_add_v4_addrs(struct inet > static void init_loopback(struct net_device *dev) > { > struct inet6_dev *idev; > + struct net_device *sp_dev; > + struct inet6_ifaddr *sp_ifa; > + struct list_head *sp_ifap;> > static void addrconf_add_linklocal(struct inet6_dev *idev, const > struct in6_addr *addr) > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > > + struct rt6_info *sp_rt; > + int i = 1; > > /* ::1 */ > > @@ -2540,6 +2545,27 @@ static void init_loopback(struct net_dev > } > > add_addr(idev, &in6addr_loopback, 128, IFA_HOST); > + > + while ((sp_dev = dev_get_by_index(dev_net(dev), i++))) { > + I think this cannot work because we may have missing index. Why no dev_get_by_name()? > + if (!strcmp(sp_dev->name, dev->name)) { > + dev_put(sp_dev); > + continue; > + } > + > + idev = ipv6_find_idev(sp_dev); > + dev_put(sp_dev); > + if (NULL == idev) > + continue; > + > + list_for_each(sp_ifap, &idev->addr_list) { > + sp_ifa = list_entry(sp_ifap, struct inet6_ifaddr, > + if_list); > + sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, 0); > + if (!IS_ERR(sp_rt)) > + ip6_ins_rt(sp_rt); > + } > + } > } lock? --yoshfuji -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, 2013-03-27 at 19:55 +0900, YOSHIFUJI Hideaki wrote: > Balakumaran Kannan wrote: > > add_addr(idev, &in6addr_loopback, 128, IFA_HOST); > > + > > + while ((sp_dev = dev_get_by_index(dev_net(dev), i++))) { > > + > > I think this cannot work because we may have missing index. > Why no dev_get_by_name()? I might 'work' because lo interface index is 1 on all network namespaces. But yes, this ugly loop is not needed at all. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
--- linux-3.9-rc4/net/ipv6/addrconf.c.orig 2013-03-27 10:40:26.382569527 +0530 +++ linux-3.9-rc4/net/ipv6/addrconf.c 2013-03-27 10:56:45.227354856 +0530 @@ -2529,6 +2529,11 @@ static void sit_add_v4_addrs(struct inet static void init_loopback(struct net_device *dev) { struct inet6_dev *idev; + struct net_device *sp_dev; + struct inet6_ifaddr *sp_ifa; + struct list_head *sp_ifap; + struct rt6_info *sp_rt; + int i = 1; /* ::1 */ @@ -2540,6 +2545,27 @@ static void init_loopback(struct net_dev } add_addr(idev, &in6addr_loopback, 128, IFA_HOST); + + while ((sp_dev = dev_get_by_index(dev_net(dev), i++))) { + + if (!strcmp(sp_dev->name, dev->name)) { + dev_put(sp_dev); + continue; + } + + idev = ipv6_find_idev(sp_dev); + dev_put(sp_dev); + if (NULL == idev) + continue; + + list_for_each(sp_ifap, &idev->addr_list) { + sp_ifa = list_entry(sp_ifap, struct inet6_ifaddr, + if_list); + sp_rt = addrconf_dst_alloc(idev, &sp_ifa->addr, 0); + if (!IS_ERR(sp_rt)) + ip6_ins_rt(sp_rt); + } + } } static void addrconf_add_linklocal(struct inet6_dev *idev, const