linux-kernel - Re: [PATCH] kernel/irq: Limit validation of cpumask_var_t to CONFIG_CPUMASK

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:   Wed, 12 Apr 2017 09:23:58 +0200 (CEST)
From:   Thomas Gleixner <tglx@...utronix.de>
To:     Matthias Kaehlcke <mka@...omium.org>
cc:     linux-kernel@...r.kernel.org,
        Grant Grundler <grundler@...omium.org>,
        Greg Hackmann <ghackmann@...gle.com>,
        Michael Davidson <md@...gle.com>
Subject: Re: [PATCH] kernel/irq: Limit validation of cpumask_var_t to
 CONFIG_CPUMASK_OFFSTACK=y

On Tue, 11 Apr 2017, Matthias Kaehlcke wrote:
> With CONFIG_CPUMASK_OFFSTACK=y cpumask_var_t is a struct cpumask
> pointer, otherwise a struct cpumask array with a single element.
> 
> irq_thread_check_affinity() validates the cpumask_var_t field in the
> interrupt descriptor by checking if it is not NULL. This works for
> both CONFIG_CPUMASK_OFFSTACK=y/n, however clang raises the following
> warning with CONFIG_CPUMASK_OFFSTACK=n:
> 
> kernel/irq/manage.c:839:28: error: address of array
> 'desc->irq_common_data.affinity' will always evaluate to 'true'
> [-Werror,-Wpointer-bool-conversion]
> 
> To get rid of the warning only validate the cpumask_var_t field when
> CONFIG_CPUMASK_OFFSTACK=y.

This ifdeffery is horrible. Can you please create a helper inline
cpumask_available() or something like that which hides this in a header
file. The irq code is probably not the only place which does this.

Thanks,

	tglx