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Message-ID: <a5036c5d-9658-37a0-3003-aa2138819b58@acm.org>
Date:   Wed, 27 Jul 2022 10:47:44 -0700
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Subject: Re: [PATCH 3/3] RDMA/srpt: Fix a use-after-free
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To:     Leon Romanovsky <leon@kernel.org>, Christoph Lameter <cl@gentwo.de>
Cc:     Jason Gunthorpe <jgg@ziepe.ca>, linux-rdma@vger.kernel.org,
        Li Zhijian <lizhijian@fujitsu.com>,
        Hillf Danton <hdanton@sina.com>,
        Mike Christie <michael.christie@oracle.com>
References: <20220726212156.1318010-1-bvanassche@acm.org>
 <20220726212156.1318010-4-bvanassche@acm.org> <YuEHOM/iGFEtaGde@unreal>
 <alpine.DEB.2.22.394.2207271426110.1244244@gentwo.de>
 <YuEwK35/xuNe24/G@unreal>
From:   Bart Van Assche <bvanassche@acm.org>
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On 7/27/22 05:31, Leon Romanovsky wrote:
> On Wed, Jul 27, 2022 at 02:26:43PM +0200, Christoph Lameter wrote:
>> On Wed, 27 Jul 2022, Leon Romanovsky wrote:
>>
>>> Please no BUG_ON() in new code.
>>
>> Do we now prefer NULL pointer dereferences causing bugs?
> 
> There are two possible scenarios.
> 1. "NULL can be in this flow." - In such case, the code should deal with
> such flow and do not crash whole machine.
> 2. "NULL can't be in this flow." - Put WARN_ON() which serves as a
> documentation/debug help to catch situations that are not possible.

Hi Leon and Christoph,

Thanks for having taken a look. Since the wwn.priv pointers cannot be 
NULL, I will remove the BUG_ON() statements that check these pointers.

Bart.