linux-kernel - Re: [PATCH] container_of.h: make container

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: <20220211140523.738c14327b03647f535c4df8@linux-foundation.org>
Date:   Fri, 11 Feb 2022 14:05:23 -0800
From:   Andrew Morton <akpm@...ux-foundation.org>
To:     Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
Cc:     linux-kernel@...r.kernel.org,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Subject: Re: [PATCH] container_of.h: make container_of const-aware

On Thu, 10 Feb 2022 20:04:34 +0300 Dmitry Baryshkov <dmitry.baryshkov@...aro.org> wrote:

> container_of() macro has one major drawback. It does not check whether
> the passed ptr has a const pointer, the result will always be a
> non-const pointer. Use a _Generic() construct (supported since gcc 4.9
> and Clang 3.0) to teach container_of that if converting a const pointer,
> the returned pointer should also have the const modifier.
> 

Nice idea, but my x86_64 allnoconfig build explodes with zillions of
warnings.

In file included from ./include/linux/list.h:5,
                 from ./include/linux/module.h:12,
                 from init/do_mounts.c:2:
./include/net/sock.h: In function 'sk_entry':
./include/linux/container_of.h:17:42: warning: return discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]