Re: [PATCH v7 04/12] perf tool: extend Perf tool with CAP_PERFMON capability support

From: James Morris
Date: Tue Feb 18 2020 - 14:24:56 EST

On Mon, 17 Feb 2020, Alexey Budankov wrote:

> Extend error messages to mention CAP_PERFMON capability as an option
> to substitute CAP_SYS_ADMIN capability for secure system performance
> monitoring and observability. Make perf_event_paranoid_check() and
> __cmd_ftrace() to be aware of CAP_PERFMON capability.
> CAP_PERFMON implements the principal of least privilege for performance
> monitoring and observability operations (POSIX IEEE 1003.1e
> principle of least privilege: A security design principle that states
> that a process or program be granted only those privileges (e.g.,
> capabilities) necessary to accomplish its legitimate function, and only
> for the time that such privileges are actually required)
> For backward compatibility reasons access to perf_events subsystem
> remains open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN
> usage for secure perf_events monitoring is discouraged with respect to
> CAP_PERFMON capability.
> Signed-off-by: Alexey Budankov <alexey.budankov@xxxxxxxxxxxxxxx>

Reviewed-by: James Morris <jamorris@xxxxxxxxxxxxxxxxxxx>

James Morris