From: Song Liu <songliubraving@fb.com>
Date: Wed, 11 Apr 2018 18:02:37 +0000
Subject: perf/core: Need CAP_SYS_ADMIN to create k/uprobe with
 perf_event_open()
Git-commit: 32e6e967fb36bf77ed99221ae3ce1909f045d8f9
Patch-mainline: v4.17-rc1
References: References: FATE#326782, bsc#1115391
Signed-off-by: Tony Jones <tonyj@suse.de>

Non-root user cannot create kprobe or uprobe through the text-based
interface (kprobe_events, uprobe_events),so they should not be able
to create probes via perf_event_open() either.

Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Song Liu <songliubraving@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 33ea4b24277b ("perf/core: Implement the 'perf_uprobe' PMU")
Fixes: e12f03d7031a ("perf/core: Implement the 'perf_kprobe' PMU")
Link: http://lkml.kernel.org/r/C0B2EFB5-C403-4BDB-9046-C14B3EE66999@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 kernel/events/core.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index d7af82827373..2d5fe26551f8 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8400,6 +8400,10 @@ static int perf_kprobe_event_init(struct perf_event *event)
 
 	if (event->attr.type != perf_kprobe.type)
 		return -ENOENT;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
 	/*
 	 * no branch sampling for probe events
 	 */
@@ -8437,6 +8441,10 @@ static int perf_uprobe_event_init(struct perf_event *event)
 
 	if (event->attr.type != perf_uprobe.type)
 		return -ENOENT;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return -EACCES;
+
 	/*
 	 * no branch sampling for probe events
 	 */