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Subject: Re: [PATCH] usb: host: xhci_debugfs: Fix a null pointer dereference
 in xhci_debugfs_create_endpoint()
To:     Jia-Ju Bai <baijiaju1990@gmail.com>,
        Greg KH <gregkh@linuxfoundation.org>
Cc:     mathias.nyman@intel.com, linux-usb@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20190504033748.17964-1-baijiaju1990@gmail.com>
 <20190504063340.GA26311@kroah.com>
 <db68433e-d655-217a-4a73-4bb83069addc@gmail.com>
From:   Mathias Nyman <mathias.nyman@linux.intel.com>
Message-ID: <939faa2c-54a8-1ae9-500c-3e25e1e2c691@linux.intel.com>
Date:   Mon, 6 May 2019 14:16:30 +0300
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On 4.5.2019 10.30, Jia-Ju Bai wrote:
> 
> 
> On 2019/5/4 14:33, Greg KH wrote:
>> On Sat, May 04, 2019 at 11:37:48AM +0800, Jia-Ju Bai wrote:
>>> In xhci_debugfs_create_slot(), kzalloc() can fail and
>>> dev->debugfs_private will be NULL.
>>> In xhci_debugfs_create_endpoint(), dev->debugfs_private is used without
>>> any null-pointer check, and can cause a null pointer dereference.
>>>
>>> To fix this bug, a null-pointer check is added in
>>> xhci_debugfs_create_endpoint().
>>>
>>> This bug is found by a runtime fuzzing tool named FIZZER written by us.
>>>
>>> Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
>> Very rare case, but nice fix.  You should put "potential" in your
>> subject line as this is something that no one should ever hit :)
> 
> Okay, Greg, thanks for this advice :)
> 

Adding patch to queue, and added "potential" to subject line.

-Mathias