sctp: Add RCU protection to assoc->transport_addr_list
peer.transport_addr_list is currently only protected by sk_sock
which is inpractical to acquire for procfs dumping purposes.
This patch adds RCU protection allowing for the procfs readers to
enter RCU read-side critical sections.
Modification of the list continues to be serialized via sk_lock.
V2: Use list_del_rcu() in sctp_association_free() to be safe
Skip transports marked dead when dumping for procfs
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index ba3f9cc..b45ed1f 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -448,7 +448,7 @@
/* Release the transport structures. */
list_for_each_safe(pos, temp, &asoc->peer.transport_addr_list) {
transport = list_entry(pos, struct sctp_transport, transports);
- list_del(pos);
+ list_del_rcu(pos);
sctp_transport_free(transport);
}
@@ -568,7 +568,7 @@
sctp_assoc_update_retran_path(asoc);
/* Remove this peer from the list. */
- list_del(&peer->transports);
+ list_del_rcu(&peer->transports);
/* Get the first transport of asoc. */
pos = asoc->peer.transport_addr_list.next;
@@ -769,7 +769,7 @@
peer->state = peer_state;
/* Attach the remote transport to our asoc. */
- list_add_tail(&peer->transports, &asoc->peer.transport_addr_list);
+ list_add_tail_rcu(&peer->transports, &asoc->peer.transport_addr_list);
asoc->peer.transport_count++;
/* If we do not yet have a primary path, set one. */