arm_pmu: Validate single/group leader events

stable inclusion
from stable-v5.10.113
commit c55327bc3712ca96dc05bc4c6aab805b6fa8bb74
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5ISAH

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=c55327bc3712ca96dc05bc4c6aab805b6fa8bb74

--------------------------------

commit e5c23779 upstream.

In the case where there is only a cycle counter available (i.e.
PMCR_EL0.N is 0) and an event other than CPU cycles is opened, the open
should fail as the event can never possibly be scheduled. However, the
event validation when an event is opened is skipped when the group
leader is opened. Fix this by always validating the group leader events.
Reported-by: NAl Grant <al.grant@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: NRob Herring <robh@kernel.org>
Acked-by: NMark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220408203330.4014015-1-robh@kernel.org
Cc: <stable@vger.kernel.org>
Signed-off-by: NWill Deacon <will@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Acked-by: NXie XiuQi <xiexiuqi@huawei.com>

drivers/perf/arm_pmu.c

@@ -398,6 +398,9 @@ validate_group(struct perf_event *event)
 	if (!validate_event(event->pmu, &fake_pmu, leader))
 		return -EINVAL;
 
+	if (event == leader)
+		return 0;
+
 	for_each_sibling_event(sibling, leader) {
 		if (!validate_event(event->pmu, &fake_pmu, sibling))
 			return -EINVAL;
@@ -487,12 +490,7 @@ __hw_perf_event_init(struct perf_event *event)
 		local64_set(&hwc->period_left, hwc->sample_period);
 	}
 
-	if (event->group_leader != event) {
-		if (validate_group(event) != 0)
-			return -EINVAL;
-	}
-
-	return 0;
+	return validate_group(event);
 }
 
 static int armpmu_event_init(struct perf_event *event)