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Subject: [PATCH v5 10/10] drivers/oprofile: open access for CAP_PERFMON
 privileged process
From:   Alexey Budankov <alexey.budankov@linux.intel.com>
To:     Peter Zijlstra <peterz@infradead.org>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
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        Paul Mackerras <paulus@samba.org>,
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        Mark Rutland <mark.rutland@arm.com>,
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        Alexei Starovoitov <ast@kernel.org>
Cc:     Jiri Olsa <jolsa@redhat.com>, Andi Kleen <ak@linux.intel.com>,
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        Igor Lubashev <ilubashe@akamai.com>,
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References: <0548c832-7f4b-dc4c-8883-3f2b6d351a08@linux.intel.com>
Organization: Intel Corp.
Message-ID: <196ea578-5079-a27f-07ca-23df0e38485c@linux.intel.com>
Date:   Mon, 20 Jan 2020 14:33:42 +0300
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Open access to monitoring for CAP_PERFMON privileged processes.
For backward compatibility reasons access to the monitoring remains
open for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage
for secure monitoring is discouraged with respect to CAP_PERFMON
capability. Providing the access under CAP_PERFMON capability singly,
without the rest of CAP_SYS_ADMIN credentials, excludes chances to
misuse the credentials and makes the operations more secure.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
---
 drivers/oprofile/event_buffer.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/oprofile/event_buffer.c b/drivers/oprofile/event_buffer.c
index 12ea4a4ad607..6c9edc8bbc95 100644
--- a/drivers/oprofile/event_buffer.c
+++ b/drivers/oprofile/event_buffer.c
@@ -113,7 +113,7 @@ static int event_buffer_open(struct inode *inode, struct file *file)
 {
 	int err = -EPERM;
 
-	if (!capable(CAP_SYS_ADMIN))
+	if (!perfmon_capable())
 		return -EPERM;
 
 	if (test_and_set_bit_lock(0, &buffer_opened))
-- 
2.20.1