ipv6: Use result arg in fib_lookup_arg consistently

arg.result is sometimes used as fib6_result and sometimes used to
hold the rt6_info. Add rt6_info to fib6_result and make the use
of arg.result consistent through ipv6 rules.

The rt6 entry is filled in for lookups returning a dst_entry, but not
for direct fib_lookups that just want a fib6_info.

Fixes: effda4dd97e8 ("ipv6: Pass fib6_result to fib lookups")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 4 deletions

diff --git a/net/ipv6/fib6_rules.c b/net/ipv6/fib6_rules.c
index dbedbe655c91..06d1b7763600 100644
--- a/net/ipv6/fib6_rules.c
+++ b/net/ipv6/fib6_rules.c
@@ -94,9 +94,11 @@ struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
                                    int flags, pol_lookup_t lookup)
 {
         if (net->ipv6.fib6_has_custom_rules) {
+                struct fib6_result res = {};
                 struct fib_lookup_arg arg = {
                         .lookup_ptr = lookup,
                         .lookup_data = skb,
+                        .result = &res,
                         .flags = FIB_LOOKUP_NOREF,
                 };
 
@@ -106,8 +108,8 @@ struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
                 fib_rules_lookup(net->ipv6.fib6_rules_ops,
                                  flowi6_to_flowi(fl6), flags, &arg);
 
-                if (arg.result)
-                        return arg.result;
+                if (res.rt6)
+                        return &res.rt6->dst;
         } else {
                 struct rt6_info *rt;
 
@@ -191,6 +193,7 @@ static int fib6_rule_action_alt(struct fib_rule *rule, struct flowi *flp,
 static int __fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
                               int flags, struct fib_lookup_arg *arg)
 {
+        struct fib6_result *res = arg->result;
         struct flowi6 *flp6 = &flp->u.ip6;
         struct rt6_info *rt = NULL;
         struct fib6_table *table;
@@ -245,7 +248,7 @@ again:
 discard_pkt:
         dst_hold(&rt->dst);
 out:
-        arg->result = rt;
+        res->rt6 = rt;
         return err;
 }
 
@@ -260,9 +263,13 @@ static int fib6_rule_action(struct fib_rule *rule, struct flowi *flp,
 
 static bool fib6_rule_suppress(struct fib_rule *rule, struct fib_lookup_arg *arg)
 {
-        struct rt6_info *rt = (struct rt6_info *) arg->result;
+        struct fib6_result *res = arg->result;
+        struct rt6_info *rt = res->rt6;
         struct net_device *dev = NULL;
 
+        if (!rt)
+                return false;
+
         if (rt->rt6i_idev)
                 dev = rt->rt6i_idev->dev;