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Subject: Re: [PATCH] media: stkwebcam: move stk_camera_read_reg() scratch
 buffer to struct stk_camera
To:     Pavel Skripkin <paskripkin@gmail.com>, mchehab@kernel.org,
        hverkuil-cisco@xs4all.nl, cai.huoqing@linux.dev,
        xose.vazquez@gmail.com
Cc:     linux-media@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20220312173049.1410977-1-trix@redhat.com>
 <65a1d178-8511-a023-2655-94540114086c@gmail.com>
 <c3723690-cacb-0c42-cc5d-397a3363b4da@redhat.com>
 <0d8dfedb-1c2c-1a70-18dc-0c4439cf4bda@gmail.com>
From:   Tom Rix <trix@redhat.com>
Message-ID: <b5711870-b047-d1cb-d272-b193175d6238@redhat.com>
Date:   Sun, 13 Mar 2022 08:35:40 -0700
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On 3/13/22 8:11 AM, Pavel Skripkin wrote:
> Hi Tom,
>
> On 3/13/22 02:48, Tom Rix wrote:
>> These do show up in my usual static analysis and it why I was looking at
>> this file.
>>
>> And was sidetracked by the short malloc.
>>
>> Unfortunately I looked and there are many other similar instances
>> treewide ~100
>>
>
> Most of them are in very old drivers and I don't think they ever be 
> fixed. I've looked into one bug reported by syzkaller and there was 
> like 30 calls w/o proper error handling in one driver. Redoing whole 
> driver logic without access to hw seems dangerous :))

 From the checkpatch change below, there are about 150 dinky allocs treewide

Here is a refactoring

https://lore.kernel.org/lkml/20220313141008.1503638-1-trix@redhat.com/

>
>
>> These aren't caught in checkpatch, so working on that..
>>
>
> I think, it's not checkpath responsibility. Maybe it worth adding such 
> check to smatch. I tried to implement such checker, but never finished 
> it :(
>
>
Poking new development to not do dinky allocs I think is worth it, here 
is my checkpatch patch

https://lore.kernel.org/lkml/20220313140827.1503359-1-trix@redhat.com/

steal the regex for smatch.

Tom

>
> With regards,
> Pavel Skripkin
>