From 14ef37b6d00eb5d06704e45989ba4c21e7be7673 Mon Sep 17 00:00:00 2001 From: Andreas Hofmeister Date: Wed, 26 Oct 2011 03:24:29 +0000 Subject: [PATCH] ipv6: fix route lookup in addrconf_prefix_rcv() The route lookup to find a previously auto-configured route for a prefixes used to use rt6_lookup(), with the prefix from the RA used as an address. However, that kind of lookup ignores routing tables, the prefix length and route flags, so when there were other matching routes, even in different tables and/or with a different prefix length, the wrong route would be manipulated. Now, a new function "addrconf_get_prefix_route()" is used for the route lookup, which searches in RT6_TABLE_PREFIX and takes the prefix-length and route flags into account. Signed-off-by: Andreas Hofmeister Signed-off-by: David S. Miller --- net/ipv6/addrconf.c | 43 ++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 40 insertions(+), 3 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index e39239e6426e..d0611a5de45f 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -1713,6 +1713,40 @@ addrconf_prefix_route(struct in6_addr *pfx, int plen, struct net_device *dev, ip6_route_add(&cfg); } + +static struct rt6_info *addrconf_get_prefix_route(const struct in6_addr *pfx, + int plen, + const struct net_device *dev, + u32 flags, u32 noflags) +{ + struct fib6_node *fn; + struct rt6_info *rt = NULL; + struct fib6_table *table; + + table = fib6_get_table(dev_net(dev), RT6_TABLE_PREFIX); + if (table == NULL) + return NULL; + + write_lock_bh(&table->tb6_lock); + fn = fib6_locate(&table->tb6_root, pfx, plen, NULL, 0); + if (!fn) + goto out; + for (rt = fn->leaf; rt; rt = rt->dst.rt6_next) { + if (rt->rt6i_dev->ifindex != dev->ifindex) + continue; + if ((rt->rt6i_flags & flags) != flags) + continue; + if ((noflags != 0) && ((rt->rt6i_flags & flags) != 0)) + continue; + dst_hold(&rt->dst); + break; + } +out: + write_unlock_bh(&table->tb6_lock); + return rt; +} + + /* Create "default" multicast route to the interface */ static void addrconf_add_mroute(struct net_device *dev) @@ -1842,10 +1876,13 @@ void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len) if (addrconf_finite_timeout(rt_expires)) rt_expires *= HZ; - rt = rt6_lookup(net, &pinfo->prefix, NULL, - dev->ifindex, 1); + rt = addrconf_get_prefix_route(&pinfo->prefix, + pinfo->prefix_len, + dev, + RTF_ADDRCONF | RTF_PREFIX_RT, + RTF_GATEWAY | RTF_DEFAULT); - if (rt && addrconf_is_prefix_route(rt)) { + if (rt) { /* Autoconf prefix route */ if (valid_lft == 0) { ip6_del_rt(rt); -- 2.34.1