ipv6: don't stop backtracking in fib6_lookup_1 if subtree does not match
In case a subtree did not match we currently stop backtracking and return
NULL (root table from fib_lookup). This could yield in invalid routing
table lookups when using subtrees.
Instead continue to backtrack until a valid subtree or node is found
and return this match.
Also remove unneeded NULL check.
Reported-by: Teco Boot <teco@inf-net.nl>
Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Cc: David Lamparter <equinox@diac24.net>
Cc: <boutier@pps.univ-paris-diderot.fr>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index bff3d82..c4ff5bb 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -993,14 +993,22 @@
if (ipv6_prefix_equal(&key->addr, args->addr, key->plen)) {
#ifdef CONFIG_IPV6_SUBTREES
- if (fn->subtree)
- fn = fib6_lookup_1(fn->subtree, args + 1);
+ if (fn->subtree) {
+ struct fib6_node *sfn;
+ sfn = fib6_lookup_1(fn->subtree,
+ args + 1);
+ if (!sfn)
+ goto backtrack;
+ fn = sfn;
+ }
#endif
- if (!fn || fn->fn_flags & RTN_RTINFO)
+ if (fn->fn_flags & RTN_RTINFO)
return fn;
}
}
-
+#ifdef CONFIG_IPV6_SUBTREES
+backtrack:
+#endif
if (fn->fn_flags & RTN_ROOT)
break;