| Message ID | 50d96f78ce6ba23c154218e81c3e24ae882a7ca8.1559872578.git.sbrivio@redhat.com |
|---|---|
| State | Changes Requested |
| Delegated to: | David Miller |
| Headers | show |
| Series | ipv6: Fix listing and flushing of cached route exceptions | expand |
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c index f468fa9b5da6..4ebae1b208e3 100644 --- a/net/ipv6/ip6_fib.c +++ b/net/ipv6/ip6_fib.c @@ -1549,7 +1549,8 @@ static struct fib6_node *fib6_locate_1(struct fib6_node *root, if (plen == fn->fn_bit) return fn; - prev = fn; + if (fn->fn_flags & RTN_RTINFO) + prev = fn; next: /*
When we perform an inexact match on FIB nodes via fib6_locate_1(), longer prefixes will be preferred to shorter ones. However, it might happen that a node, with higher fn_bit value than some other, has no valid routing information. In this case, we'll pick that node, but it will be discarded by the check on RTN_RTINFO in fib6_locate(), and we might miss nodes with valid routing information but with lower fn_bit value. This is apparent when a routing exception is created for a default route: # ip -6 route list fc00:1::/64 dev veth_A-R1 proto kernel metric 256 pref medium fc00:2::/64 dev veth_A-R2 proto kernel metric 256 pref medium fc00:4::1 via fc00:2::2 dev veth_A-R2 metric 1024 pref medium fe80::/64 dev veth_A-R1 proto kernel metric 256 pref medium fe80::/64 dev veth_A-R2 proto kernel metric 256 pref medium default via fc00:1::2 dev veth_A-R1 metric 1024 pref medium # ip -6 route list cache fc00:4::1 via fc00:2::2 dev veth_A-R2 metric 1024 expires 593sec mtu 1500 pref medium fc00:3::1 via fc00:1::2 dev veth_A-R1 metric 1024 expires 593sec mtu 1500 pref medium # ip -6 route flush cache # node for default route is discarded Failed to send flush request: No such process # ip -6 route list cache fc00:3::1 via fc00:1::2 dev veth_A-R1 metric 1024 expires 586sec mtu 1500 pref medium Check right away if the node has a RTN_RTINFO flag, before replacing the 'prev' pointer, that indicates the longest matching prefix found so far. Fixes: 38fbeeeeccdb ("ipv6: prepare fib6_locate() for exception table") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> --- v2: No changes net/ipv6/ip6_fib.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)