diff mbox series

[4/7] target: fix cmd_count ref leak

Message ID 1603666998-8086-5-git-send-email-michael.christie@oracle.com (mailing list archive)
State New, archived
Headers show
Series target: fix up locking in IO paths | expand

Commit Message

Mike Christie Oct. 25, 2020, 11:03 p.m. UTC 
percpu_ref_init sets the refcount to 1 and percpu_ref_kill drops it.
Drivers like iscsi and loop do not call target_sess_cmd_list_set_waiting
during session shutdown though, so they have been calling
percpu_ref_exit
with a refcount still taken and leaking the cmd_counts memory.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
---
 drivers/target/target_core_transport.c | 8 ++++++++
 1 file changed, 8 insertions(+)
diff mbox series

Patch

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index ee2d2db..465b6583 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -238,6 +238,14 @@  int transport_init_session(struct se_session *se_sess)
 
 void transport_uninit_session(struct se_session *se_sess)
 {
+	/*
+	 * Drivers like iscsi and loop do not call
+	 * target_sess_cmd_list_set_waiting during session shutdown so we
+	 * have to drop the ref taken at init time here.
+	 */
+	if (!se_sess->sess_tearing_down)
+		percpu_ref_put(&se_sess->cmd_count);
+
 	percpu_ref_exit(&se_sess->cmd_count);
 }