Re: [PATCH] cpupower: Correctly detect if running as root

From: Rafael J. Wysocki
Date: Sun Dec 14 2014 - 16:08:04 EST


On Sunday, December 14, 2014 01:36:52 PM Michal Privoznik wrote:
> Some operations, like frequency-set, need root privileges. However,
> the way that this is detected is not correct. The getuid() is called,
> while in fact geteuid() should be. This way we can allow
> distributions or users to set SETUID flags on the cpupower binary if
> they want to and let regular users change the cpu frequency governor.
>
> Signed-off-by: Michal Privoznik <mprivozn@xxxxxxxxxx>

An ACK from Thomas is needed.

> ---
> tools/power/cpupower/utils/cpupower.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/power/cpupower/utils/cpupower.c b/tools/power/cpupower/utils/cpupower.c
> index 7cdcf88..9ea9143 100644
> --- a/tools/power/cpupower/utils/cpupower.c
> +++ b/tools/power/cpupower/utils/cpupower.c
> @@ -199,7 +199,7 @@ int main(int argc, const char *argv[])
> }
>
> get_cpu_info(0, &cpupower_cpu_info);
> - run_as_root = !getuid();
> + run_as_root = !geteuid();
> if (run_as_root) {
> ret = uname(&uts);
> if (!ret && !strcmp(uts.machine, "x86_64") &&
>

--
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.
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