Re: [syzbot] [usb?] WARNING in wdm_rxwork/usb_submit_urb (2)

[Hillf Danton]

On Wed, 24 Apr 2024 21:40:22 -0700
> syzbot has found a reproducer for the following issue on:
> 
> HEAD commit:    a160e1202ca3 usb: dwc3: qcom: Add multiport suspend/resume..
> git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=166f3d27180000

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git  usb-testing

--- x/drivers/usb/class/cdc-wdm.c
+++ y/drivers/usb/class/cdc-wdm.c
@@ -311,11 +311,12 @@ static void wdm_int_callback(struct urb
 		&& !test_bit(WDM_DISCONNECTING, &desc->flags)
 		&& !test_bit(WDM_SUSPENDING, &desc->flags)) {
 		rv = usb_submit_urb(desc->response, GFP_ATOMIC);
+		if (rv)
+			clear_bit(WDM_RESPONDING, &desc->flags);
 		dev_dbg(&desc->intf->dev, "submit response URB %d\n", rv);
 	}
 	spin_unlock_irqrestore(&desc->iuspin, flags);
 	if (rv < 0) {
-		clear_bit(WDM_RESPONDING, &desc->flags);
 		if (rv == -EPERM)
 			return;
 		if (rv == -ENOMEM) {
--