4.18-stable review patch. If anyone has any objections, please let me know.
------------------ From: Erik Schmauss <[email protected]> [ Upstream commit f016b19a9275089a2ab06c2144567c2ad8d5d6ad ] The value coming from acpi_hw_read() should not be used if it returns an error code, so check the status returned by it before using that value in two places in acpi_hw_register_read(). Reported-by: Mark Gross <[email protected]> Signed-off-by: Erik Schmauss <[email protected]> [ rjw: Changelog ] Signed-off-by: Rafael J. Wysocki <[email protected]> Signed-off-by: Sasha Levin <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/acpi/acpica/hwregs.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/drivers/acpi/acpica/hwregs.c +++ b/drivers/acpi/acpica/hwregs.c @@ -528,13 +528,18 @@ acpi_status acpi_hw_register_read(u32 re status = acpi_hw_read(&value64, &acpi_gbl_FADT.xpm2_control_block); - value = (u32)value64; + if (ACPI_SUCCESS(status)) { + value = (u32)value64; + } break; case ACPI_REGISTER_PM_TIMER: /* 32-bit access */ status = acpi_hw_read(&value64, &acpi_gbl_FADT.xpm_timer_block); - value = (u32)value64; + if (ACPI_SUCCESS(status)) { + value = (u32)value64; + } + break; case ACPI_REGISTER_SMI_COMMAND_BLOCK: /* 8-bit access */

