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Date:   Thu, 17 May 2018 16:42:52 -0400 (EDT)
Message-Id: <20180517.164252.466789510812778167.davem@davemloft.net>
To:     mmullins@fb.com
Cc:     netdev@vger.kernel.org, davejwatson@fb.com,
        linux-kernel@vger.kernel.org, aviadye@mellanox.com, doronrk@fb.com
Subject: Re: [PATCH net] tls: don't use stack memory in a scatterlist
From:   David Miller <davem@davemloft.net>
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From: Matt Mullins <mmullins@fb.com>
Date: Thu, 17 May 2018 20:28:46 +0000

> On Thu, 2018-05-17 at 14:50 -0400, David Miller wrote:
>> I'm surprised this problem wasn't discovered sooner.  How exactly did you
>> discover it?  Did you actually see it trigger or is this purely from code
>> inspection?
> 
> Honestly, I'm not sure how it got uncovered, but it was observed at
> runtime.  Doron Roberts-Kedes hit a null pointer dereference so we
> turned on CONFIG_DEBUG_SG -- then it became a proper
> BUG_ON(!virt_addr_valid(buf)); in sg_set_buf.

Fair enough, thanks for the info.