linux-kernel - Re: [PATCH] drivers/perf: arm_spe: Use perf_allow

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: <20240807111520.GC37996@noisy.programming.kicks-ass.net>
Date: Wed, 7 Aug 2024 13:15:20 +0200
From: Peter Zijlstra <peterz@...radead.org>
To: James Clark <james.clark@...aro.org>
Cc: linux-arm-kernel@...ts.infradead.org, Al Grant <al.grant@....com>,
	Will Deacon <will@...nel.org>, Mark Rutland <mark.rutland@....com>,
	Ingo Molnar <mingo@...hat.com>,
	Arnaldo Carvalho de Melo <acme@...nel.org>,
	Namhyung Kim <namhyung@...nel.org>,
	Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
	Jiri Olsa <jolsa@...nel.org>, Ian Rogers <irogers@...gle.com>,
	Adrian Hunter <adrian.hunter@...el.com>,
	"Liang, Kan" <kan.liang@...ux.intel.com>,
	Paul Moore <paul@...l-moore.com>, James Morris <jmorris@...ei.org>,
	"Serge E. Hallyn" <serge@...lyn.com>, linux-kernel@...r.kernel.org,
	linux-perf-users@...r.kernel.org,
	linux-security-module@...r.kernel.org
Subject: Re: [PATCH] drivers/perf: arm_spe: Use perf_allow_kernel() for
 permissions

On Wed, Aug 07, 2024 at 11:54:41AM +0100, James Clark wrote:
> diff --git a/kernel/events/core.c b/kernel/events/core.c
> index aa3450bdc227..4a69583e329a 100644
> --- a/kernel/events/core.c
> +++ b/kernel/events/core.c
> @@ -417,6 +417,7 @@ static struct kmem_cache *perf_event_cache;
>   *   2 - disallow kernel profiling for unpriv
>   */
>  int sysctl_perf_event_paranoid __read_mostly = 2;
> +EXPORT_SYMBOL_GPL(sysctl_perf_event_paranoid);

I'm never a fan of exporting variables. Perhaps create a helper function
that returns the value and use that where required?

That avoids modules getting the idea it would be okay to change this
valie themselves.