[PATCH AUTOSEL 4.19 42/59] ACPICA: actypes.h: Expand the ACPI_ACCESS_ definitions

From: Sasha Levin
Date: Mon Jan 17 2022 - 22:03:07 EST


From: Mark Langsdorf <mlangsdo@xxxxxxxxxx>

[ Upstream commit f81bdeaf816142e0729eea0cc84c395ec9673151 ]

ACPICA commit bc02c76d518135531483dfc276ed28b7ee632ce1

The current ACPI_ACCESS_*_WIDTH defines do not provide a way to
test that size is small enough to not cause an overflow when
applied to a 32-bit integer.

Rather than adding more magic numbers, add ACPI_ACCESS_*_SHIFT,
ACPI_ACCESS_*_MAX, and ACPI_ACCESS_*_DEFAULT #defines and
redefine ACPI_ACCESS_*_WIDTH in terms of the new #defines.

This was inititally reported on Linux where a size of 102 in
ACPI_ACCESS_BIT_WIDTH caused an overflow error in the SPCR
initialization code.

Link: https://github.com/acpica/acpica/commit/bc02c76d
Signed-off-by: Mark Langsdorf <mlangsdo@xxxxxxxxxx>
Signed-off-by: Bob Moore <robert.moore@xxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
include/acpi/actypes.h | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h
index 2939a6cd7fecb..9fc1dfc7f4c32 100644
--- a/include/acpi/actypes.h
+++ b/include/acpi/actypes.h
@@ -532,8 +532,14 @@ typedef u64 acpi_integer;
* Can be used with access_width of struct acpi_generic_address and access_size of
* struct acpi_resource_generic_register.
*/
-#define ACPI_ACCESS_BIT_WIDTH(size) (1 << ((size) + 2))
-#define ACPI_ACCESS_BYTE_WIDTH(size) (1 << ((size) - 1))
+#define ACPI_ACCESS_BIT_SHIFT 2
+#define ACPI_ACCESS_BYTE_SHIFT -1
+#define ACPI_ACCESS_BIT_MAX (31 - ACPI_ACCESS_BIT_SHIFT)
+#define ACPI_ACCESS_BYTE_MAX (31 - ACPI_ACCESS_BYTE_SHIFT)
+#define ACPI_ACCESS_BIT_DEFAULT (8 - ACPI_ACCESS_BIT_SHIFT)
+#define ACPI_ACCESS_BYTE_DEFAULT (8 - ACPI_ACCESS_BYTE_SHIFT)
+#define ACPI_ACCESS_BIT_WIDTH(size) (1 << ((size) + ACPI_ACCESS_BIT_SHIFT))
+#define ACPI_ACCESS_BYTE_WIDTH(size) (1 << ((size) + ACPI_ACCESS_BYTE_SHIFT))

/*******************************************************************************
*
--
2.34.1