From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <edumazet@google.com>
Subject: Re: [PATCH v2] net: core: Prevent from dereferencing null pointer when
Date: Mon, 24 Apr 2017 18:10:32 -0700
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 <20170424.120235.438297438450788048.davem@davemloft.net> <20170425010052.GA8717@fqdn.specialj.com>
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Cc: David Miller <davem@davemloft.net>, netdev <netdev@vger.kernel.org>
To: Myungho Jung <mhjungk@gmail.com>
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On Mon, Apr 24, 2017 at 6:00 PM, Myungho Jung <mhjungk@gmail.com> wrote:
> On Mon, Apr 24, 2017 at 12:02:35PM -0400, David Miller wrote:
>> From: Myungho Jung <mhjungk@gmail.com>
>> Date: Thu, 20 Apr 2017 16:59:20 -0700
>>
>> > Added NULL check to make __dev_kfree_skb_irq consistent with kfree
>> > family of functions.
>> >
>> > Link: https://bugzilla.kernel.org/show_bug.cgi?id=195289
>> >
>> > Signed-off-by: Myungho Jung <mhjungk@gmail.com>
>> > ---
>> > Changes in v2:
>> >  - Correct category in subject
>>
>> This subject line is an incomplete sentence.
>>
>> This patch prevents dereferenccing a null pointer when "what"?
>
> As it was reported on bugzilla, it would happen when plugging p54 usb device
> to RPi2. But, i'm not 100% sure that this patch will resolve the issue because
> the reporter didn't try my patch yet and I don't have the device to test.
>
> And there might be some other places calling the function without checking
> null pointer. The thing is that only the function don't check null among
> kfree functions. So, I just hope this patch will prevent potential oops
> issues.

Okay, but your patch title was : "net: core: Prevent from
dereferencing null pointer when"

"when" is usually followed by other words.