[PATCH AUTOSEL 5.19 17/38] HID: nintendo: fix rumble worker null pointer deref

From: Sasha Levin
Date: Sat Sep 10 2022 - 17:18:10 EST


From: "Daniel J. Ogorchock" <djogorchock@xxxxxxxxx>

[ Upstream commit 1ff89e06c2e5fab30274e4b02360d4241d6e605e ]

We can dereference a null pointer trying to queue work to a destroyed
workqueue.

If the device is disconnected, nintendo_hid_remove is called, in which
the rumble_queue is destroyed. Avoid using that queue to defer rumble
work once the controller state is set to JOYCON_CTLR_STATE_REMOVED.

This eliminates the null pointer dereference.

Signed-off-by: Daniel J. Ogorchock <djogorchock@xxxxxxxxx>
Signed-off-by: Jiri Kosina <jkosina@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/hid/hid-nintendo.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/hid/hid-nintendo.c b/drivers/hid/hid-nintendo.c
index 4b1173957c17c..f33a03c96ba68 100644
--- a/drivers/hid/hid-nintendo.c
+++ b/drivers/hid/hid-nintendo.c
@@ -1222,6 +1222,7 @@ static void joycon_parse_report(struct joycon_ctlr *ctlr,

spin_lock_irqsave(&ctlr->lock, flags);
if (IS_ENABLED(CONFIG_NINTENDO_FF) && rep->vibrator_report &&
+ ctlr->ctlr_state != JOYCON_CTLR_STATE_REMOVED &&
(msecs - ctlr->rumble_msecs) >= JC_RUMBLE_PERIOD_MS &&
(ctlr->rumble_queue_head != ctlr->rumble_queue_tail ||
ctlr->rumble_zero_countdown > 0)) {
@@ -1546,12 +1547,13 @@ static int joycon_set_rumble(struct joycon_ctlr *ctlr, u16 amp_r, u16 amp_l,
ctlr->rumble_queue_head = 0;
memcpy(ctlr->rumble_data[ctlr->rumble_queue_head], data,
JC_RUMBLE_DATA_SIZE);
- spin_unlock_irqrestore(&ctlr->lock, flags);

/* don't wait for the periodic send (reduces latency) */
- if (schedule_now)
+ if (schedule_now && ctlr->ctlr_state != JOYCON_CTLR_STATE_REMOVED)
queue_work(ctlr->rumble_queue, &ctlr->rumble_worker);

+ spin_unlock_irqrestore(&ctlr->lock, flags);
+
return 0;
}

--
2.35.1