From 541a496644512ebed429b33f19a3fadfb19c6ee7 Mon Sep 17 00:00:00 2001
From: Thomas Richter <tmricht@linux.ibm.com>
Date: Tue, 14 Jun 2022 12:40:46 +0200
Subject: [PATCH] s390/pai: Prevent invalid event number for pai_crypto PMU

The pai_crypto PMU has to check the event number. It has to be in
the supported range. This is not the case, the lower limit is not
checked. Fix this and obey the lower limit.

Fixes: 39d62336f5c1 ("s390/pai: add support for cryptography counters")

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Suggested-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
---
 arch/s390/kernel/perf_pai_crypto.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/s390/kernel/perf_pai_crypto.c b/arch/s390/kernel/perf_pai_crypto.c
index 8c1545946d85e..188c6cf09c7a2 100644
--- a/arch/s390/kernel/perf_pai_crypto.c
+++ b/arch/s390/kernel/perf_pai_crypto.c
@@ -193,8 +193,9 @@ static int paicrypt_event_init(struct perf_event *event)
 	/* PAI crypto PMU registered as PERF_TYPE_RAW, check event type */
 	if (a->type != PERF_TYPE_RAW && event->pmu->type != a->type)
 		return -ENOENT;
-	/* PAI crypto event must be valid */
-	if (a->config > PAI_CRYPTO_BASE + paicrypt_cnt)
+	/* PAI crypto event must be in valid range */
+	if (a->config < PAI_CRYPTO_BASE ||
+	    a->config > PAI_CRYPTO_BASE + paicrypt_cnt)
 		return -EINVAL;
 	/* Allow only CPU wide operation, no process context for now. */
 	if (event->hw.target || event->cpu == -1)
-- 
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