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To:     Arnaldo Carvalho de Melo <acme@kernel.org>
Cc:     Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Andi Kleen <ak@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        "linux-security-module@vger.kernel.org" 
        <linux-security-module@vger.kernel.org>,
        "linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>,
        linux-man@vger.kernel.org
From:   Alexey Budankov <alexey.budankov@linux.intel.com>
Subject: [PATCH v1 0/2] doc/admin-guide: update perf-security.rst with
 CAP_PERFMON usage flows
Organization: Intel Corp.
Message-ID: <161a51d3-7cdf-f9ee-c438-42bb7404693e@linux.intel.com>
Date:   Mon, 19 Oct 2020 20:15:14 +0300
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Assignment of CAP_PERFMON [1] Linux capability to an executable located
on a file system requires extended attributes (xattrs) [2] to be supported
by the file system. Even if the file system supports xattrs an fs device
should be mounted with permission to use xattrs for files located on the
device (e.g. without nosuid option [3]). No xattrs support and nosuid
mounts are quite common in HPC and Cloud multiuser environments thus
applicability of privileged Perf user groups based on file capabilities
[4] is limited in that environments. Alternative method to confer Linux
capabilities into a process does still exist and it is thru creation of
capabilities-enabled-semi-privileged shell environment. Usage of this
method to extend privileged Perf user groups approach is documented in
this patch set as an extension to perf-security.rst admin guide file.

[1] https://man7.org/linux/man-pages/man7/capabilities.7.html
[2] https://man7.org/linux/man-pages/man7/xattr.7.html
[3] https://man7.org/linux/man-pages/man8/mount.8.html
[4] https://www.kernel.org/doc/html/latest/admin-guide/perf-security.html#privileged-perf-users-groups

---
Alexey Budankov (2):
  doc/admin-guide: note credentials consolidation under CAP_PERFMON
  doc/admin-guide: document creation of CAP_PERFMON privileged shell

 Documentation/admin-guide/perf-security.rst | 81 ++++++++++++++++++---
 1 file changed, 70 insertions(+), 11 deletions(-)

-- 
2.24.1