RDMA/rtrs-clt: Fix memory leak of not-freed sess->stats and stats->pcpu_stats

sess->stats and sess->stats->pcpu_stats objects are freed
when sysfs entry is removed. If something wrong happens and
session is closed before sysfs entry is created,
sess->stats and sess->stats->pcpu_stats objects are not freed.

This patch adds freeing of them at three places:
1. When client uses wrong address and session creation fails.
2. When client fails to create a sysfs entry.
3. When client adds wrong address via sysfs add_path.

Fixes: 215378b8 ("RDMA/rtrs: client: sysfs interface functions")
Link: https://lore.kernel.org/r/20210528113018.52290-21-jinpu.wang@ionos.comSigned-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/ulp/rtrs/rtrs-clt.c

@@ -2765,6 +2765,8 @@ struct rtrs_clt *rtrs_clt_open(struct rtrs_clt_ops *ops,
 		if (err) {
 			list_del_rcu(&sess->s.entry);
 			rtrs_clt_close_conns(sess, true);
+			free_percpu(sess->stats->pcpu_stats);
+			kfree(sess->stats);
 			free_sess(sess);
 			goto close_all_sess;
 		}
@@ -2773,6 +2775,8 @@ struct rtrs_clt *rtrs_clt_open(struct rtrs_clt_ops *ops,
 		if (err) {
 			list_del_rcu(&sess->s.entry);
 			rtrs_clt_close_conns(sess, true);
+			free_percpu(sess->stats->pcpu_stats);
+			kfree(sess->stats);
 			free_sess(sess);
 			goto close_all_sess;
 		}
@@ -3048,6 +3052,8 @@ int rtrs_clt_create_path_from_sysfs(struct rtrs_clt *clt,
 close_sess:
 	rtrs_clt_remove_path_from_arr(sess);
 	rtrs_clt_close_conns(sess, true);
+	free_percpu(sess->stats->pcpu_stats);
+	kfree(sess->stats);
 	free_sess(sess);
 
 	return err;