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From: Dapeng Mi <dapeng1.mi@linux.intel.com>
To: Sean Christopherson <seanjc@google.com>,
	Paolo Bonzini <pbonzini@redhat.com>,
	Jim Mattson <jmattson@google.com>
Cc: kvm@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Zhenyu Wang <zhenyuw@linux.intel.com>,
	Zhang Xiong <xiong.y.zhang@intel.com>,
	Mingwei Zhang <mizhang@google.com>,
	Like Xu <like.xu.linux@gmail.com>,
	Jinrong Liang <cloudliang@tencent.com>,
	Dapeng Mi <dapeng1.mi@intel.com>,
	Dapeng Mi <dapeng1.mi@linux.intel.com>
Subject: [kvm-unit-tests Patch v3 02/11] x86: pmu: Enlarge cnt[] length to 64 in check_counters_many()
Date: Wed,  3 Jan 2024 11:14:00 +0800
Message-Id: <20240103031409.2504051-3-dapeng1.mi@linux.intel.com>
In-Reply-To: <20240103031409.2504051-1-dapeng1.mi@linux.intel.com>
References: <20240103031409.2504051-1-dapeng1.mi@linux.intel.com>
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Considering there are already 8 GP counters and 4 fixed counters on
latest Intel processors, like Sapphire Rapids. The original cnt[] array
length 10 is definitely not enough to cover all supported PMU counters on these
new processors even through currently KVM only supports 3 fixed counters
at most. This would cause out of bound memory access and may trigger
false alarm on PMU counter validation

It's probably more and more GP and fixed counters are introduced in the
future and then directly extends the cnt[] array length to 64 once and
for all.

Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
---
 x86/pmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/x86/pmu.c b/x86/pmu.c
index 0def28695c70..a13b8a8398c6 100644
--- a/x86/pmu.c
+++ b/x86/pmu.c
@@ -254,7 +254,7 @@ static void check_fixed_counters(void)
 
 static void check_counters_many(void)
 {
-	pmu_counter_t cnt[10];
+	pmu_counter_t cnt[64];
 	int i, n;
 
 	for (i = 0, n = 0; n < pmu.nr_gp_counters; i++) {
-- 
2.34.1