platform/surface: fix potential integer overflow on shift of a int
authorColin Ian King <colin.king@canonical.com>
Mon, 11 Jan 2021 14:46:48 +0000 (14:46 +0000)
committerHans de Goede <hdegoede@redhat.com>
Wed, 13 Jan 2021 09:25:10 +0000 (10:25 +0100)
commitd26cbdd27f8c4ff2f3df227a8bc5782697ecce51
tree8352fb176843fd6f5b3a6e23ab1aac7245c5ba10
parentd69cd7eea93eb59a93061beeb43e4f5e19afc4ea
platform/surface: fix potential integer overflow on shift of a int

The left shift of int 32 bit integer constant 1 is evaluated using 32 bit
arithmetic and then passed as a 64 bit function argument. In the case where
func is 32 or more this can lead to an oveflow.  Avoid this by shifting
using the BIT_ULL macro instead.

Addresses-Coverity: ("Unintentional integer overflow")
Fixes: fc00bc8ac1da ("platform/surface: Add Surface ACPI Notify driver")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210111144648.20498-1-colin.king@canonical.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
drivers/platform/surface/surface_acpi_notify.c