[PATCH net] sctp: check duplicate node before inserting a new transport

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



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@xxxxxxxxxx>
Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx>
---
 net/sctp/input.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/net/sctp/input.c b/net/sctp/input.c
index 458e506..f65245b 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);
 
-- 
2.1.0

--
To unsubscribe from this list: send the line "unsubscribe linux-sctp" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux Networking Development]     [Linux OMAP]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux