[PATCH v2 1/2] usb: gadget: composite: avoid warning on aborted delayed status

[Keisuke Tsukuda <catnyaaan@outlook.com>]

A SET_CONFIGURATION request that disables the current configuration, or a
disconnect, can abort a control transfer whose status stage was delayed by
a function driver. The asynchronous function work can nevertheless finish
later and call usb_composite_setup_continue() after reset_config() has
cleared delayed_status.

This is an expected consequence of aborting the old control transfer, and
does not require a kernel warning. Keep the diagnostic available under
dynamic debug and ignore the obsolete completion as before.

Fixes: 2bac51a1827a ("usb: gadget: composite: reset delayed_status on reset_config")
Reported-by: syzbot+a83a5a1ba9ff57935171@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=a83a5a1ba9ff57935171
Signed-off-by: Keisuke Tsukuda <tkdkei@outlook.jp>
---
 drivers/usb/gadget/composite.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index df39e34..1b22381 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -2740,7 +2740,7 @@ void usb_composite_setup_continue(struct usb_composite_dev *cdev)
 	spin_lock_irqsave(&cdev->lock, flags);
 
 	if (cdev->delayed_status == 0) {
-		WARN(cdev, "%s: Unexpected call\n", __func__);
+		DBG(cdev, "%s: Ignoring obsolete call\n", __func__);
 
 	} else if (--cdev->delayed_status == 0) {
 		DBG(cdev, "%s: Completing delayed status\n", __func__);
-- 
2.50.1 (Apple Git-155)