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Subject: Re: [f2fs-dev] KMSAN: uninit-value in f2fs_lookup
To:     Eric Biggers <ebiggers@kernel.org>, Chao Yu <yuchao0@huawei.com>
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 <eb03a5c9-eb77-eb91-e17f-8a3273aab7da@huawei.com>
 <20200925163819.GA3315208@gmail.com> <20200925164538.GB3315208@gmail.com>
Cc:     syzbot <syzbot+0eac6f0bbd558fd866d7@syzkaller.appspotmail.com>,
        glider@google.com, jaegeuk@kernel.org,
        linux-f2fs-devel@lists.sourceforge.net,
        linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com
From:   Chao Yu <chao@kernel.org>
Message-ID: <36d3ddc1-e8d1-6d0e-c1ea-aff198740182@kernel.org>
Date:   Sat, 26 Sep 2020 07:17:09 +0800
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On 2020-9-26 0:45, Eric Biggers wrote:
> On Fri, Sep 25, 2020 at 09:38:19AM -0700, Eric Biggers wrote:
>> On Fri, Sep 25, 2020 at 05:06:33PM +0800, Chao Yu wrote:
>>> Hi,
>>>
>>> I don't see any problem here, thanks for your report. :)
>>>
>>> Thanks,
>>
>> What about if max_depth == 0 in __f2fs_find_entry()?  Then __f2fs_find_entry()
>> would return NULL without initializing *res_page.
>
> ... and I now see Dan Carpenter already pointed this out.  I was a bit late!

Thanks for your check as well. :)

Thanks,

>
> - Eric
>