[PATCH] ACPI: LPIT: fix u32 multiplication overflow

From: Nikita Kiryushin
Date: Thu Nov 09 2023 - 13:09:13 EST


In lpit_update_residency there is a possibility of overflow
in multiplication, if tsc_khz is large enough (> UINT_MAX/1000).

Change multiplication to mul_u32_u32.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: eeb2d80d502a ("ACPI / LPIT: Add Low Power Idle Table (LPIT) support")
Signed-off-by: Nikita Kiryushin <kiryushin@xxxxxxxx>
---
drivers/acpi/acpi_lpit.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/acpi/acpi_lpit.c b/drivers/acpi/acpi_lpit.c
index c5598b6d5db8..794962c5c88e 100644
--- a/drivers/acpi/acpi_lpit.c
+++ b/drivers/acpi/acpi_lpit.c
@@ -105,7 +105,7 @@ static void lpit_update_residency(struct lpit_residency_info *info,
return;
info->frequency = lpit_native->counter_frequency ?
- lpit_native->counter_frequency : tsc_khz * 1000;
+ lpit_native->counter_frequency : mul_u32_u32(tsc_khz, 1000U);
if (!info->frequency)
info->frequency = 1;
-- 2.34.1