1002 if ((quirks & MT_QUIRK_IGNORE_DUPLICATES) && mt) { 1003 struct input_mt_slot *i_slot = &mt->slots[slotnum]; 1004 1005 if (input_mt_is_active(i_slot) && 1006 input_mt_is_used(mt, i_slot)) 1007 return -EAGAIN; 1008 } We previously assumed 'mt' could be null (see line 1002). The following situation is similar, so add a judgement. Signed-off-by: Pan Zhang <zhangpan26@xxxxxxxxxx> --- drivers/hid/hid-multitouch.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c index 3cfeb16..368de81 100644 --- a/drivers/hid/hid-multitouch.c +++ b/drivers/hid/hid-multitouch.c @@ -1019,7 +1019,7 @@ static int mt_process_slot(struct mt_device *td, struct input_dev *input, tool = MT_TOOL_DIAL; else if (unlikely(!confidence_state)) { tool = MT_TOOL_PALM; - if (!active && + if (!active && mt && input_mt_is_active(&mt->slots[slotnum])) { /* * The non-confidence was reported for -- 2.7.4