sctp has changed to use rhlist for transport rhashtable since commit
7fda702f9315 ("sctp: use new rhlist interface on sctp transport
rhashtable").
But rhltable_insert_key doesn't check the duplicate node when inserting
a node, unlike rhashtable_lookup_insert_key. It may cause duplicate
assoc/transport in rhashtable. like:
client (addr A, B) server (addr X, Y)
connect to X INIT (1)
------------>
connect to Y INIT (2)
------------>
INIT_ACK (1)
<------------
INIT_ACK (2)
<------------
After sending INIT (2), one transport will be created and hashed into
rhashtable. But when receiving INIT_ACK (1) and processing the address
params, another transport will be created and hashed into rhashtable
with the same addr Y and EP as the last transport. This will confuse
the assoc/transport's lookup.
This patch is to fix it by returning err if any duplicate node exists
before inserting it.
Fixes: 7fda702f9315 ("sctp: use new rhlist interface on sctp transport rhashtable")
Reported-by: Fabio M. Di Nitto <fdinitto@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
int sctp_hash_transport(struct sctp_transport *t)
{
+ struct sctp_transport *transport;
+ struct rhlist_head *tmp, *list;
struct sctp_hash_cmp_arg arg;
int err;
arg.paddr = &t->ipaddr;
arg.lport = htons(t->asoc->base.bind_addr.port);
+ list = rhltable_lookup(&sctp_transport_hashtable, &arg,
+ sctp_hash_params);
+
+ rhl_for_each_entry_rcu(transport, tmp, list, node)
+ if (transport->asoc->ep == t->asoc->ep) {
+ err = -EEXIST;
+ goto out;
+ }
+
err = rhltable_insert_key(&sctp_transport_hashtable, &arg,
&t->node, sctp_hash_params);
+
+out:
if (err)
pr_err_once("insert transport fail, errno %d\n", err);