The BAD_MADT_ENTRY() macro is designed to work for all of the subtables of the MADT. In the ACPI 5.1 version of the spec, the struct for the GICC subtable (struct acpi_madt_generic_interrupt) is 76 bytes long; in ACPI 6.0, the struct is 80 bytes long. But, there is only one definition in ACPICA for this struct -- and that is the 6.0 version. Hence, when BAD_MADT_ENTRY() compares the struct size to the length in the GICC subtable, it fails if 5.1 structs are in use, and there are systems in the wild that have them.
This patch adds the BAD_MADT_GICC_ENTRY() that checks the GICC subtable only, accounting for the difference in specification versions that are possible. The BAD_MADT_ENTRY() will continue to work as is for all other MADT subtables.
This code is being added to an arm64 header file since that is currently the only architecture using the GICC subtable of the MADT. As a GIC is specific to ARM, it is also unlikely the subtable will be used elsewhere.
Fixes: aeb823bbacc2 (ACPICA: ACPI 6.0: Add changes for FADT table.) Signed-off-by: Al Stone al.stone@linaro.org --- arch/arm64/include/asm/acpi.h | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h index 39248d3..a3c26a4 100644 --- a/arch/arm64/include/asm/acpi.h +++ b/arch/arm64/include/asm/acpi.h @@ -19,6 +19,17 @@ #include <asm/psci.h> #include <asm/smp_plat.h>
+/* Macros for consistency checks of the GICC subtable of MADT */ +#define ACPI_MADT_GICC_51_LENGTH 76 +#define ACPI_MADT_GICC_60_LENGTH 80 + +#define BAD_MADT_GICC_ENTRY(entry, end) ( \ + (!entry) || (unsigned long)entry + sizeof(*entry) > end || \ + ((ACPI_FADT_SPEC_VERSION == ACPI_FADT_SPEC_VERSION_51) && \ + (entry->header.length != ACPI_MADT_GICC_51_LENGTH)) || \ + ((ACPI_FADT_SPEC_VERSION == ACPI_FADT_SPEC_VERSION_60) && \ + (entry->header.length != ACPI_MADT_GICC_60_LENGTH))) + /* Basic configuration for ACPI */ #ifdef CONFIG_ACPI /* ACPI table mapping after acpi_gbl_permanent_mmap is set */