From 6e22e3af7bb3a7b9dc53cb4687659f6e63fca427 Mon Sep 17 00:00:00 2001
From: Jia-Ju Bai <baijiaju1990@gmail.com>
Date: Sat, 1 Sep 2018 16:12:10 +0800
Subject: [PATCH] usb: cdc-wdm: Fix a sleep-in-atomic-context bug in
service_outstanding_interrupt()
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@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
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 bec581fb7c636..656d247819c9d 100644
--- a/drivers/usb/class/cdc-wdm.c
+++ b/drivers/usb/class/cdc-wdm.c
@@ -460,7 +460,7 @@ 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,