From 66d58af7f4af53e8318e852efa31a7cb0e31bfb6 Mon Sep 17 00:00:00 2001 From: David Howells Date: Sat, 17 Sep 2016 10:49:12 +0100 Subject: [PATCH] rxrpc: Fix the putting of client connections In rxrpc_put_one_client_conn(), if a connection has RXRPC_CONN_COUNTED set on it, then it's accounted for in rxrpc_nr_client_conns and may be on various lists - and this is cleaned up correctly. However, if the connection doesn't have RXRPC_CONN_COUNTED set on it, then the put routine returns rather than just skipping the extra bit of cleanup. Fix this by making the extra bit of clean up conditional instead and always killing off the connection. This manifests itself as connections with a zero usage count hanging around in /proc/net/rxrpc_conns because the connection allocated, but discarded, due to a race with another process that set up a parallel connection, which was then shared instead. Signed-off-by: David Howells --- net/rxrpc/conn_client.c | 28 +++++++++++++--------------- 1 file changed, 13 insertions(+), 15 deletions(-) diff --git a/net/rxrpc/conn_client.c b/net/rxrpc/conn_client.c index 9344a8416ceb..5a675c43cace 100644 --- a/net/rxrpc/conn_client.c +++ b/net/rxrpc/conn_client.c @@ -818,7 +818,7 @@ idle_connection: static struct rxrpc_connection * rxrpc_put_one_client_conn(struct rxrpc_connection *conn) { - struct rxrpc_connection *next; + struct rxrpc_connection *next = NULL; struct rxrpc_local *local = conn->params.local; unsigned int nr_conns; @@ -834,24 +834,22 @@ rxrpc_put_one_client_conn(struct rxrpc_connection *conn) ASSERTCMP(conn->cache_state, ==, RXRPC_CONN_CLIENT_INACTIVE); - if (!test_bit(RXRPC_CONN_COUNTED, &conn->flags)) - return NULL; - - spin_lock(&rxrpc_client_conn_cache_lock); - nr_conns = --rxrpc_nr_client_conns; + if (test_bit(RXRPC_CONN_COUNTED, &conn->flags)) { + spin_lock(&rxrpc_client_conn_cache_lock); + nr_conns = --rxrpc_nr_client_conns; + + if (nr_conns < rxrpc_max_client_connections && + !list_empty(&rxrpc_waiting_client_conns)) { + next = list_entry(rxrpc_waiting_client_conns.next, + struct rxrpc_connection, cache_link); + rxrpc_get_connection(next); + rxrpc_activate_conn(next); + } - next = NULL; - if (nr_conns < rxrpc_max_client_connections && - !list_empty(&rxrpc_waiting_client_conns)) { - next = list_entry(rxrpc_waiting_client_conns.next, - struct rxrpc_connection, cache_link); - rxrpc_get_connection(next); - rxrpc_activate_conn(next); + spin_unlock(&rxrpc_client_conn_cache_lock); } - spin_unlock(&rxrpc_client_conn_cache_lock); rxrpc_kill_connection(conn); - if (next) rxrpc_activate_channels(next); -- 2.30.2