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Subject: Re: Re: [PATCH] usb: asix: Fix uninit-value in asix_mdio_write
To:     David Miller <davem@davemloft.net>
References: <0000000000009763320594f993ee@google.com>
 <20191107004404.23707-1-tranmanphong@gmail.com>
 <20191107.152118.922830217121663373.davem@davemloft.net>
From:   Phong Tran <tranmanphong@gmail.com>
Message-ID: <5679efce-797a-ea2c-f7fb-882ac450e9d2@gmail.com>
Date:   Sun, 10 Nov 2019 21:11:11 +0700
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On 11/8/19 6:21 AM, David Miller wrote:
> From: Phong Tran <tranmanphong@gmail.com>
> Date: Thu,  7 Nov 2019 07:44:04 +0700
> 
>> The local variables use without initilization value.
>> This fixes the syzbot report.
>>
>> Reported-by: syzbot+7dc7c28d4577bbe55b10@syzkaller.appspotmail.com
>>
>> Test result:
>>
>> https://groups.google.com/d/msg/syzkaller-bugs/3H_n05x_sPU/sUoHhxgAAgAJ
>>
>> Signed-off-by: Phong Tran <tranmanphong@gmail.com>
> 
> There are several more situations in this file where the data blob passed
> to asix_read_cmd() is read without pre-initialization not checking the
> return value from asix_read_cmd().
> 
> So, syzbot can see some of them but not all of them, yet all of them
> are buggy and should be fixed.
> 
> These kinds of patches drive me absolutely crazy :-)
> 
> Really, one of two things needs to happen, either asix_read_cmd() clears
> the incoming buffer unconditionally, 

thank you for your suggestion.
Sent Patch v2 reply-to this mail thread.

regards,
Phong.