[PATCH] input: appletouch: initialize work before device registration

[PATCH] input: appletouch: initialize work before device registration

[Pavel Skripkin]

Syzbot has reported warning in __flush_work(). This warning is caused by
work->func == NULL, which means missing work initialization.

This may happen, since input_dev->close() calls cancel_work_sync(&dev->work),
but dev->work initalization happens _after_ input_register_device()
call.

So this patch moves dev->work initialization before registering input
device

Fixes: 5a6eb676d3bc ("Input: appletouch - improve powersaving for Geyser3 devices")
Reported-and-tested-by: syzbot+b88c5eae27386b252bbd@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
---

Happy New Year and Merry Christmas! :)


With regards,
Pavel Skripkin

---
 drivers/input/mouse/appletouch.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/input/mouse/appletouch.c b/drivers/input/mouse/appletouch.c
index bfa26651c0be..627048bc6a12 100644
--- a/drivers/input/mouse/appletouch.c
+++ b/drivers/input/mouse/appletouch.c
@@ -916,6 +916,8 @@ static int atp_probe(struct usb_interface *iface,
 	set_bit(BTN_TOOL_TRIPLETAP, input_dev->keybit);
 	set_bit(BTN_LEFT, input_dev->keybit);
 
+	INIT_WORK(&dev->work, atp_reinit);
+
 	error = input_register_device(dev->input);
 	if (error)
 		goto err_free_buffer;
@@ -923,8 +925,6 @@ static int atp_probe(struct usb_interface *iface,
 	/* save our data pointer in this interface device */
 	usb_set_intfdata(iface, dev);
 
-	INIT_WORK(&dev->work, atp_reinit);
-
 	return 0;
 
  err_free_buffer:
-- 
2.34.1

Re: [PATCH] input: appletouch: initialize work before device registration

[Dmitry Torokhov]

On Thu, Dec 30, 2021 at 05:11:51PM +0300, Pavel Skripkin wrote:
> Syzbot has reported warning in __flush_work(). This warning is caused by
> work->func == NULL, which means missing work initialization.
> 
> This may happen, since input_dev->close() calls cancel_work_sync(&dev->work),
> but dev->work initalization happens _after_ input_register_device()
> call.
> 
> So this patch moves dev->work initialization before registering input
> device
> 
> Fixes: 5a6eb676d3bc ("Input: appletouch - improve powersaving for Geyser3 devices")
> Reported-and-tested-by: syzbot+b88c5eae27386b252bbd@syzkaller.appspotmail.com
> Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>

Applied, thank you.

-- 
Dmitry