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Date: Wed, 7 Jun 2017 10:43:14 -0400 (EDT)
From: Alan Stern <stern@rowland.harvard.edu>
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To: Andrey Konovalov <andreyknvl@google.com>
cc: Felipe Balbi <balbi@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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        Dmitry Vyukov <dvyukov@google.com>, Kostya Serebryany <kcc@google.com>,
        syzkaller <syzkaller@googlegroups.com>
Subject: Re: usb/gadget: another GPF in usb_gadget_unregister_driver
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On Wed, 7 Jun 2017, Andrey Konovalov wrote:

> Hi,
> 
> I've got the following error report while fuzzing the kernel with syzkaller.
> 
> On commit b29794ec95c6856b316c2295904208bf11ffddd9 (4.12-rc4+).
> 
> This looks quite similar to
> https://groups.google.com/forum/#!topic/syzkaller/HDawLBeeORI

It does look very similar, but that problem was supposed to have been 
fixed by commit 7b0173811260 ("usb: gadget: udc: core: fix return code 
of usb_gadget_probe_driver()").

> I'm able to reproduce this, so I can collect some debug traces if needed.

Can you provide an strace or the equivalent?

Alan Stern