4.18-stable review patch. If anyone has any objections, please let me know.
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From: Erik Schmauss erik.schmauss@intel.com
[ 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 mark.gross@intel.com Signed-off-by: Erik Schmauss erik.schmauss@intel.com [ rjw: Changelog ] Signed-off-by: Rafael J. Wysocki rafael.j.wysocki@intel.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 */