This is a note to let you know that I've just added the patch titled
ACPI: LPIT: Avoid u32 multiplication overflow
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
acpi-lpit-avoid-u32-multiplication-overflow.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 8cdc64640abf09c310337b144cb939ad88dc0834
Author: Nikita Kiryushin <kiryushin@xxxxxxxx>
Date: Thu Nov 9 21:08:59 2023 +0300
ACPI: LPIT: Avoid u32 multiplication overflow
[ Upstream commit 56d2eeda87995245300836ee4dbd13b002311782 ]
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>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
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;
