RDS: lock rds_conn_count decrement in rds_conn_destroy()

rds_conn_destroy() can race with all other modifications of the
rds_conn_count but it was modifying the count without locking.

Signed-off-by: Zach Brown <zach.brown@oracle.com>

diff --git a/net/rds/connection.c b/net/rds/connection.c
index 0de40d9563ca82a0d2505c7e2381b79238a15dee..75a1a37d64d34e5975bbce1c262454a87f2c483f 100644 (file)
--- a/net/rds/connection.c
+++ b/net/rds/connection.c
@@ -313,6 +313,7 @@ void rds_conn_shutdown(struct rds_connection *conn)
 void rds_conn_destroy(struct rds_connection *conn)
 {
        struct rds_message *rm, *rtmp;
+       unsigned long flags;
 
        rdsdebug("freeing conn %p for %pI4 -> "
                 "%pI4\n", conn, &conn->c_laddr,
@@ -350,7 +351,9 @@ void rds_conn_destroy(struct rds_connection *conn)
        BUG_ON(!list_empty(&conn->c_retrans));
        kmem_cache_free(rds_conn_slab, conn);
 
+       spin_lock_irqsave(&rds_conn_lock, flags);
        rds_conn_count--;
+       spin_unlock_irqrestore(&rds_conn_lock, flags);
 }
 EXPORT_SYMBOL_GPL(rds_conn_destroy);