Commit cd2b7087 authored by Xin Long's avatar Xin Long Committed by David S. Miller

sctp: check duplicate node before inserting a new transport

sctp has changed to use rhlist for transport rhashtable since commit
7fda702f ("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: 7fda702f ("sctp: use new rhlist interface on sctp transport rhashtable")
Reported-by: default avatarFabio M. Di Nitto <fdinitto@redhat.com>
Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 7e1392fb
...@@ -872,6 +872,8 @@ void sctp_transport_hashtable_destroy(void) ...@@ -872,6 +872,8 @@ void sctp_transport_hashtable_destroy(void)
int sctp_hash_transport(struct sctp_transport *t) int sctp_hash_transport(struct sctp_transport *t)
{ {
struct sctp_transport *transport;
struct rhlist_head *tmp, *list;
struct sctp_hash_cmp_arg arg; struct sctp_hash_cmp_arg arg;
int err; int err;
...@@ -882,8 +884,19 @@ int sctp_hash_transport(struct sctp_transport *t) ...@@ -882,8 +884,19 @@ int sctp_hash_transport(struct sctp_transport *t)
arg.paddr = &t->ipaddr; arg.paddr = &t->ipaddr;
arg.lport = htons(t->asoc->base.bind_addr.port); 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, err = rhltable_insert_key(&sctp_transport_hashtable, &arg,
&t->node, sctp_hash_params); &t->node, sctp_hash_params);
out:
if (err) if (err)
pr_err_once("insert transport fail, errno %d\n", err); pr_err_once("insert transport fail, errno %d\n", err);
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment