linux-kernel - Re: [PATCH v1] drivers: edac: Drop unnecessary error check for debugfs_create

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 28 Aug 2023 16:00:41 +0200
From:   Michal Simek <michal.simek@....com>
To:     Atul Kumar Pant <atulpant.linux@...il.com>
CC:     <shubhrajyoti.datta@....com>, <sai.krishna.potthuri@....com>,
        <bp@...en8.de>, <tony.luck@...el.com>, <james.morse@....com>,
        <mchehab@...nel.org>, <rric@...nel.org>,
        <linux-edac@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>, <shuah@...nel.org>
Subject: Re: [PATCH v1] drivers: edac: Drop unnecessary error check for
 debugfs_create_dir



On 8/28/23 15:35, Atul Kumar Pant wrote:
> On Fri, Aug 25, 2023 at 09:31:54AM +0200, Michal Simek wrote:
>>
>>
>> On 8/15/23 22:38, Atul Kumar Pant wrote:
>>> This patch removes the error checking for debugfs_create_dir.
>>
>> Avoid using "This patch".
> 
> 	Thanks for pointing this out. I'll remember this.
> 
>>
>>> Even if we get an error from this function, other debugfs APIs will
>>> handle the error value and doesn't crash in that case. Hence caller can
>>> safely ignore the errors that occur during the creation of debugfs nodes.
>>
>> First of all which issue do you have? Did you see that folder is not created?
> 
> 	I have not seen any issue as such. But going by the comments before
> 	the debugfs_create_dir API (https://elixir.bootlin.com/linux/latest/source/fs/debugfs/inode.c#L583),
> 	we can ignore safely ignore the return value from this API.
> 
>>
>> I am not quite sure if this is the right behavior.
>> In the code there is
>> 135         if (!parent)
>> 136                 parent = edac_debugfs;
>>
>> It means you are right that if creating ocm folder can fail and properties
>> will be still created under edac_debugfs but is this the right behavior?
>>
>> altera_edac/armada_xp_edac/i10nm/i5100/igen6/others are checking return
>> value that's why I can't see any reason to remove this checking from one
>> driver.
>>
>> If you want to fix all please send patch for all but I don't think it will
>> improve situation and it will just hide different issue if creating folder
>> fails.
> 
> 	Understood your point. Are you suggesting that we should keep these
> 	checks as it is, or should I fix for all the drivers and upload the
> 	patch ?

Up to Boris to decide but I would say keep it as is. Even debugfs is not stable 
interface I would like to be informed if something fails. But just 2c.

Thanks,
Michal