From cd2b708750582e327789d8fb07c6eb5f79f7759f Mon Sep 17 00:00:00 2001 From: Xin Long Date: Fri, 17 Feb 2017 16:35:24 +0800 Subject: sctp: check duplicate node before inserting a new transport 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 Signed-off-by: Xin Long Signed-off-by: David S. Miller --- net/sctp/input.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'net/sctp/input.c') diff --git a/net/sctp/input.c b/net/sctp/input.c index 704ad19..fc45896 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -872,6 +872,8 @@ void sctp_transport_hashtable_destroy(void) 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; @@ -882,8 +884,19 @@ int sctp_hash_transport(struct sctp_transport *t) 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); -- cgit v1.1