David reported breakages of VRF scenarios due to the
commit 6e617de84e87 ("net: avoid a full fib lookup when rp_filter is
disabled."): the local addresses based test is too strict when VRFs
are in place.
With this change we fall-back to a full lookup when custom fib rules
are in place; so that we address the VRF use case and possibly other
similar issues in non trivial setups.
Reported-by: David Ahern <dsah...@gmail.com>
Fixes: 6e617de84e87 ("net: avoid a full fib lookup when rp_filter is disabled.")
Signed-off-by: Paolo Abeni <pab...@redhat.com>
---
net/ipv4/fib_frontend.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index f02819134ba2..95a904098dd1 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -405,10 +405,12 @@ int fib_validate_source(struct sk_buff *skb, __be32 src,
__be32 dst,
(dev->ifindex != oif || !IN_DEV_TX_REDIRECTS(idev))) {
if (IN_DEV_ACCEPT_LOCAL(idev))
goto ok;
- /* if no local routes are added from user space we can check
- * for local addresses looking-up the ifaddr table
+ /* with custom local routes in place, checking local addresses
+ * only will be too optimistic, with custom rules, checking
+ * local addresses only can be too strict, e.g. due to vrf
*/
- if (net->ipv4.fib_has_custom_local_routes)
+ if (net->ipv4.fib_has_custom_local_routes ||
+ net->ipv4.fib_has_custom_rules)
goto full_check;
if (inet_lookup_ifaddr_rcu(net, src))
return -EINVAL;
--
2.13.6
