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Subject: Re: [PATCH] ata: pata_platform: Fix a NULL pointer dereference in
 __pata_platform_probe()
To:     Zhou Qingyang <zhou1615@umn.edu>
CC:     <kjlu@umn.edu>, Damien Le Moal <damien.lemoal@opensource.wdc.com>,
        Alexander Shiyan <shc_work@mail.ru>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
        Jens Axboe <axboe@kernel.dk>, <linux-ide@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <20220124164525.53068-1-zhou1615@umn.edu>
From:   Sergey Shtylyov <s.shtylyov@omp.ru>
Organization: Open Mobile Platform
Message-ID: <578d6a7e-1488-43b9-9bfe-9c99c88da4fd@omp.ru>
Date:   Tue, 25 Jan 2022 12:46:56 +0300
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On 1/24/22 7:45 PM, Zhou Qingyang wrote:

> In __pata_platform_probe(), devm_kzalloc() is assigned to ap->ops and
> there is a dereference of it right after that, which could introduce a
> NULL pointer dereference bug.
> 
> Fix this by adding a NULL check of ap->ops.
> 
> This bug was found by a static analyzer.
> 
> Builds with 'make allyesconfig' show no new warnings,
> and our static analyzer no longer warns about this code.
> 
> Fixes: f3d5e4f18dba ("ata: pata_of_platform: Allow to use 16-bit wide data transfer")
> Signed-off-by: Zhou Qingyang <zhou1615@umn.edu>

Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>

[...]

MBR, Sergey