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Date:   Tue, 13 Apr 2021 12:57:24 -0400
From:   Alan Stern <stern@rowland.harvard.edu>
To:     Dmitry Vyukov <dvyukov@google.com>
Cc:     syzbot <syzbot+eb4674092e6cc8d9e0bd@syzkaller.appspotmail.com>,
        Andrey Konovalov <andreyknvl@gmail.com>,
        Felipe Balbi <balbi@kernel.org>,
        Dan Carpenter <dan.carpenter@oracle.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        LKML <linux-kernel@vger.kernel.org>,
        USB list <linux-usb@vger.kernel.org>,
        syzkaller-bugs <syzkaller-bugs@googlegroups.com>
Subject: Re: [syzbot] general protection fault in gadget_setup
Message-ID: <20210413165724.GD1454681@rowland.harvard.edu>
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On Tue, Apr 13, 2021 at 06:47:47PM +0200, Dmitry Vyukov wrote:
> On Tue, Apr 13, 2021 at 6:13 PM Alan Stern <stern@rowland.harvard.edu> wrote:
> > Hopefully this patch will make the race a lot more likely to occur.  Is
> > there any way to tell syzkaller to test it, despite the fact that
> > syzkaller doesn't think it has a reproducer for this issue?
> 
> If there is no reproducer the only way syzbot can test it is if it's
> in linux-next under CONFIG_DEBUG_AID_FOR_SYZBOT:
> http://bit.do/syzbot#no-custom-patches

There _is_ a theoretical reproducer: the test that provoked syzkaller's 
original bug report.  But syzkaller doesn't realize that it is (or may 
be) a reproducer.

It ought to be possible to ask syzkaller to run a particular test that 
it has done before, with a patch applied -- and without having to add 
anything to linux-next.

Alan Stern