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Subject: Re: [Linux-kernel-mentees] [PATCH] fs: fix KMSAN uninit-value bug by
 initializing nd in do_file_open_root
To:     Al Viro <viro@zeniv.linux.org.uk>,
        Greg KH <gregkh@linuxfoundation.org>
Cc:     Eric Biggers <ebiggers@kernel.org>, linux-fsdevel@vger.kernel.org,
        linux-kernel-mentees@lists.linuxfoundation.org,
        syzbot+4191a44ad556eacc1a7a@syzkaller.appspotmail.com,
        linux-kernel@vger.kernel.org
References: <20200916052657.18683-1-anant.thazhemadam@gmail.com>
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 <20200917002238.GO3421308@ZenIV.linux.org.uk>
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 <20200919165558.GH3421308@ZenIV.linux.org.uk>
From:   Anant Thazhemadam <anant.thazhemadam@gmail.com>
Message-ID: <26d881e5-f68a-b3b7-4cb0-04a3c6c384ac@gmail.com>
Date:   Sat, 19 Sep 2020 17:03:50 +0530
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On 19-09-2020 22:25, Al Viro wrote:
> On Sat, Sep 19, 2020 at 05:17:27PM +0100, Al Viro wrote:
>
>> Lovely...  That would get an empty path and non-directory for a starting
>> point, but it should end up with LAST_ROOT in nd->last_type.  Which should
>> not be able to reach the readers of those fields...  Which kernel had
>> that been on?
> Yecchhh...  I see what's going on; I suspect that this ought to be enough.
> Folks, could somebody test it on the original reproducer setup?

Sure. I can do that.

Thanks,
Anant