Re: [syzbot] [usb?] general protection fault in usb_gadget_udc_reset (4)

[Alan Stern]

On Sun, Mar 08, 2026 at 09:01:01AM -0700, syzbot wrote:
> Hello,
> 
> syzbot has tested the proposed patch and the reproducer did not trigger any issue:
> 
> Reported-by: syzbot+19bed92c97bee999e5db@xxxxxxxxxxxxxxxxxxxxxxxxx
> Tested-by: syzbot+19bed92c97bee999e5db@xxxxxxxxxxxxxxxxxxxxxxxxx
> 
> Tested on:
> 
> commit:         65169048 Merge tag 'spi-fix-v7.0-rc2' of git://git.ker..
> git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> console output: https://syzkaller.appspot.com/x/log.txt?x=133f3fe6580000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=2a019678b1a3a692
> dashboard link: https://syzkaller.appspot.com/bug?extid=19bed92c97bee999e5db
> compiler:       Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
> patch:          https://syzkaller.appspot.com/x/patch.diff?x=178dc8ba580000
> 
> Note: testing is done by a robot and is best-effort only.

That's not very helpful.  Let's try a slightly different approach.

Alan Stern

#syz test: upstream 651690480a96

Index: usb-devel/drivers/usb/gadget/udc/core.c
===================================================================
--- usb-devel.orig/drivers/usb/gadget/udc/core.c
+++ usb-devel/drivers/usb/gadget/udc/core.c
@@ -1192,7 +1192,9 @@ EXPORT_SYMBOL_GPL(usb_udc_vbus_handler);
 void usb_gadget_udc_reset(struct usb_gadget *gadget,
 		struct usb_gadget_driver *driver)
 {
+	dev_info(&gadget->dev, "Reset #1, driver %p\n", driver);
 	driver->reset(gadget);
+	dev_info(&gadget->dev, "Reset #2\n");
 	usb_gadget_set_state(gadget, USB_STATE_DEFAULT);
 }
 EXPORT_SYMBOL_GPL(usb_gadget_udc_reset);