[PATCH v2 1/1] usb: typec: ucsi: Fix NULL pointer access

[Andrei Kuchynski]

Resources should be released only after all threads that utilize them
have been destroyed.
This commit ensures that resources are not released prematurely by waiting
for the associated workqueue to complete before deallocating them.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: b9aa02ca39a4 ("usb: typec: ucsi: Add polling mechanism for partner tasks like alt mode checking")
Signed-off-by: Andrei Kuchynski <akuchynski@xxxxxxxxxxxx>
---
 drivers/usb/typec/ucsi/ucsi.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index fcf499cc9458..43b4f8207bb3 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -1825,11 +1825,11 @@ static int ucsi_init(struct ucsi *ucsi)
 
 err_unregister:
 	for (con = connector; con->port; con++) {
+		if (con->wq)
+			destroy_workqueue(con->wq);
 		ucsi_unregister_partner(con);
 		ucsi_unregister_altmodes(con, UCSI_RECIPIENT_CON);
 		ucsi_unregister_port_psy(con);
-		if (con->wq)
-			destroy_workqueue(con->wq);
 
 		usb_power_delivery_unregister_capabilities(con->port_sink_caps);
 		con->port_sink_caps = NULL;
@@ -2013,10 +2013,6 @@ void ucsi_unregister(struct ucsi *ucsi)
 
 	for (i = 0; i < ucsi->cap.num_connectors; i++) {
 		cancel_work_sync(&ucsi->connector[i].work);
-		ucsi_unregister_partner(&ucsi->connector[i]);
-		ucsi_unregister_altmodes(&ucsi->connector[i],
-					 UCSI_RECIPIENT_CON);
-		ucsi_unregister_port_psy(&ucsi->connector[i]);
 
 		if (ucsi->connector[i].wq) {
 			struct ucsi_work *uwork;
@@ -2032,6 +2028,11 @@ void ucsi_unregister(struct ucsi *ucsi)
 			destroy_workqueue(ucsi->connector[i].wq);
 		}
 
+		ucsi_unregister_partner(&ucsi->connector[i]);
+		ucsi_unregister_altmodes(&ucsi->connector[i],
+					 UCSI_RECIPIENT_CON);
+		ucsi_unregister_port_psy(&ucsi->connector[i]);
+
 		usb_power_delivery_unregister_capabilities(ucsi->connector[i].port_sink_caps);
 		ucsi->connector[i].port_sink_caps = NULL;
 		usb_power_delivery_unregister_capabilities(ucsi->connector[i].port_source_caps);
-- 
2.49.0.rc0.332.g42c0ae87b1-goog