HID: nintendo: fix rumble worker null pointer deref

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@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/hid-nintendo.c b/drivers/hid/hid-nintendo.c
index 92ac4f605f134606486b20027b80e097b0d67223..6028af3c3aae54929f1fc354b0d7bc36ce9a4ebf 100644 (file)
--- a/drivers/hid/hid-nintendo.c
+++ b/drivers/hid/hid-nintendo.c
@@ -1221,6 +1221,7 @@ 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)) {
@@ -1545,12 +1546,13 @@ 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;
 }