wdm_in_callback() is a completion handler function for the USB driver.
So it should not sleep. But it calls service_outstanding_interrupt(),
which calls usb_submit_urb() with GFP_KERNEL.
To fix this bug, GFP_KERNEL is replaced with GFP_ATOMIC.
This bug is found by my static analysis tool DSAC.
Signed-off-by: Jia-Ju Bai <baijiaju1990@xxxxxxxxx>
---
v2:
* Add more description.
---
drivers/usb/class/cdc-wdm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/usb/class/cdc-wdm.c b/drivers/usb/class/cdc-wdm.c
index a0d284ef3f40..632a2bfabc08 100644
--- a/drivers/usb/class/cdc-wdm.c
+++ b/drivers/usb/class/cdc-wdm.c
@@ -458,7 +458,7 @@ static int service_outstanding_interrupt(struct wdm_device *desc)
set_bit(WDM_RESPONDING, &desc->flags);
spin_unlock_irq(&desc->iuspin);
- rv = usb_submit_urb(desc->response, GFP_KERNEL);
+ rv = usb_submit_urb(desc->response, GFP_ATOMIC);
spin_lock_irq(&desc->iuspin);
if (rv) {
dev_err(&desc->intf->dev,
--
2.17.0
