rtnetlink: fallback to UNSPEC if current family has no doit callback
We need to use PF_UNSPEC in case the requested family has no doit
callback, otherwise this now fails with EOPNOTSUPP instead of running the
unspec doit callback, as before.
Fixes: 6853dd488119 ("rtnetlink: protect handler table with rcu")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 59eda69..9e9f141 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -4221,6 +4221,12 @@ static int rtnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
return err;
}
+ doit = READ_ONCE(handlers[type].doit);
+ if (!doit) {
+ family = PF_UNSPEC;
+ handlers = rcu_dereference(rtnl_msg_handlers[family]);
+ }
+
flags = READ_ONCE(handlers[type].flags);
if (flags & RTNL_FLAG_DOIT_UNLOCKED) {
refcount_inc(&rtnl_msg_handlers_ref[family]);
