linux-kernel - Re: [0/2] powerpc/powernv/vas: Adjustments for two function implementations

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]

Message-ID: <d3818747-cb02-409f-99a0-7e8c1338b859@web.de>
Date: Tue, 16 Apr 2024 14:04:39 +0200
From: Markus Elfring <Markus.Elfring@....de>
To: Michael Ellerman <mpe@...erman.id.au>, linuxppc-dev@...ts.ozlabs.org,
 kernel-janitors@...r.kernel.org, "Aneesh Kumar K.V"
 <aneesh.kumar@...nel.org>, Christophe Leroy <christophe.leroy@...roup.eu>,
 "Naveen N. Rao" <naveen.n.rao@...ux.ibm.com>,
 Nicholas Piggin <npiggin@...il.com>
Cc: LKML <linux-kernel@...r.kernel.org>, cocci@...ia.fr
Subject: Re: [0/2] powerpc/powernv/vas: Adjustments for two function
 implementations

>>>   One function call less in vas_window_alloc() after error detection
>>
>> https://patchwork.ozlabs.org/project/linuxppc-dev/patch/1f1c21cf-c34c-418c-b00c-8e6474f12612@web.de/
>
> It introduced a new goto and label to avoid a kfree(NULL) call, but
> kfree() explicitly accepts NULL and handles it. So it complicates the
> source code for no gain.

I proposed to avoid such a redundant function call for the affected
exception handling.

>>>   Return directly after a failed kasprintf() in map_paste_region()
>>
>> https://patchwork.ozlabs.org/project/linuxppc-dev/patch/f46f04bc-613c-4e98-b602-4c5120556b09@web.de/
>
> Basically the same reasoning. And it also changes the function from
> having two return paths (success and error), to three.

See also a corresponding advice once more from the section “7) Centralized exiting of functions”:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/coding-style.rst?h=v6.9-rc4#n532

Regards,
Markus