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Date:   Wed, 16 Nov 2022 18:16:43 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Denis Arefev <arefev@swemel.ru>
Cc:     Alexander Viro <viro@zeniv.linux.org.uk>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        trufanov@swemel.ru, vfh@swemel.ru
Subject: Re: [PATCH] namespace: Added pointer check in copy_mnt_ns()
Message-ID: <Y3UpC8AT8gTeupib@casper.infradead.org>
References: <20221116091255.84576-1-arefev@swemel.ru>
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On Wed, Nov 16, 2022 at 12:12:55PM +0300, Denis Arefev wrote:
> Return value of a function 'next_mnt' is dereferenced at
> namespace.c:3377 without checking for null,
>  but it is usually checked for this function
> 
> Found by Linux Verification Center (linuxtesting.org) with SVACE.

You need to do human analysis, not just send the results from a bot.
What conditions can lead to this function returning NULL?  Do we
already know those conditions can or cannot hold?