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Message-ID: <ffda7120-c2aa-d093-a2a5-f5d169c7651e@gmail.com>
Date:   Thu, 10 Nov 2022 12:18:50 +0800
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Subject: Re: [PATCH] module: Fix NULL vs IS_ERR checking for
 module_get_next_page
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To:     Luis Chamberlain <mcgrof@kernel.org>
Cc:     Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        linux-modules@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20221110025834.1624394-1-linmq006@gmail.com>
 <Y2x5a1YVbvmqrK9O@bombadil.infradead.org>
From:   Miaoqian Lin <linmq006@gmail.com>
In-Reply-To: <Y2x5a1YVbvmqrK9O@bombadil.infradead.org>
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Hi,

On 2022/11/10 12:09, Luis Chamberlain wrote:
> On Thu, Nov 10, 2022 at 06:58:34AM +0400, Miaoqian Lin wrote:
>> The module_get_next_page() function return error pointers on error
>> instead of NULL.
>> Use IS_ERR() to check the return value to fix this.
>>
>> Fixes: b1ae6dc41eaa ("module: add in-kernel support for decompressing")
>> Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
>> ---
> Thanks queued up. How did you find out? Just code inspection? I see
> chances are low of this triggering, but just curious how you found it.
I found this by static analysis, specifically, I obtained functions that return error pointers and

inspected whether their callers followed the correct specification.

>   Luis