From: Bob Moore Date: Wed, 26 Apr 2017 08:17:43 +0000 (+0800) Subject: ACPICA: Disassembler: Enhance resource descriptor detection X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=da28e1955d7f;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git ACPICA: Disassembler: Enhance resource descriptor detection ACPICA commit ba5020b2dbe1538e4ccd7ac2dfd8843a690c007f This change enhances the detection of resource descriptors within a buffer object. For the end_tag opcode, the second byte is defined to be either a checksum or zero. All known ASL compilers insert a zero for this byte. The disassembler now ensures this byte is zero before deciding that a buffer should be disassembled to a resource descriptor. This helps eliminate incorrect decisions when attempting to disassemble a buffer to a resource descriptor. Link: https://github.com/acpica/acpica/commit/ba5020b2 Signed-off-by: Bob Moore Signed-off-by: Lv Zheng Signed-off-by: Rafael J. Wysocki --- diff --git a/drivers/acpi/acpica/utresrc.c b/drivers/acpi/acpica/utresrc.c index ff096d9755b9..e0587c85bafd 100644 --- a/drivers/acpi/acpica/utresrc.c +++ b/drivers/acpi/acpica/utresrc.c @@ -474,6 +474,15 @@ acpi_ut_walk_aml_resources(struct acpi_walk_state *walk_state, return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG); } + /* + * The end_tag opcode must be followed by a zero byte. + * Although this byte is technically defined to be a checksum, + * in practice, all ASL compilers set this byte to zero. + */ + if (*(aml + 1) != 0) { + return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG); + } + /* Return the pointer to the end_tag if requested */ if (!user_function) {