Windows seems to allow arbitrary table signatures for Load/load_table opcodes: ACPI BIOS Error (bug): Table has invalid signature [PRAD] (0x44415250) So this patch removes dynamic load signature checks. However we need to find a way to avoid table loading against tables like MADT. This is not covered by this commit. This Windows behavior has been validated on link #1. An end user bug report can also be found on link #2. This patch also includes simple cleanup for static load signature check code. Reported by Ye Xiaolong, Fixed by Lv Zheng. Link: https://github.com/acpica/acpica/pull/121 [#1] Link: https://bugzilla.kernel.org/show_bug.cgi?id=118601 [#2] Reported-by: Ye Xiaolong <xiaolong.ye@xxxxxxxxx> Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx> --- drivers/acpi/acpica/tbinstal.c | 28 ---------------------------- drivers/acpi/acpica/tbxfload.c | 2 +- 2 files changed, 1 insertion(+), 29 deletions(-) diff --git a/drivers/acpi/acpica/tbinstal.c b/drivers/acpi/acpica/tbinstal.c index ee74515..9d21296 100644 --- a/drivers/acpi/acpica/tbinstal.c +++ b/drivers/acpi/acpica/tbinstal.c @@ -222,34 +222,6 @@ acpi_tb_install_standard_table(acpi_physical_address address, (void)acpi_ut_acquire_mutex(ACPI_MTX_TABLES); if (reload) { - /* - * Validate the incoming table signature. - * - * 1) Originally, we checked the table signature for "SSDT" or "PSDT". - * 2) We added support for OEMx tables, signature "OEM". - * 3) Valid tables were encountered with a null signature, so we just - * gave up on validating the signature, (05/2008). - * 4) We encountered non-AML tables such as the MADT, which caused - * interpreter errors and kernel faults. So now, we once again allow - * only "SSDT", "OEMx", and now, also a null signature. (05/2011). - */ - if ((new_table_desc.signature.ascii[0] != 0x00) && - (!ACPI_COMPARE_NAME - (&new_table_desc.signature, ACPI_SIG_SSDT)) - && (strncmp(new_table_desc.signature.ascii, "OEM", 3))) { - ACPI_BIOS_ERROR((AE_INFO, - "Table has invalid signature [%4.4s] (0x%8.8X), " - "must be SSDT or OEMx", - acpi_ut_valid_nameseg(new_table_desc. - signature. - ascii) ? - new_table_desc.signature. - ascii : "????", - new_table_desc.signature.integer)); - - status = AE_BAD_SIGNATURE; - goto unlock_and_exit; - } /* Check if table is already registered */ diff --git a/drivers/acpi/acpica/tbxfload.c b/drivers/acpi/acpica/tbxfload.c index b71ce3b..d81f442 100644 --- a/drivers/acpi/acpica/tbxfload.c +++ b/drivers/acpi/acpica/tbxfload.c @@ -206,7 +206,7 @@ acpi_status acpi_tb_load_namespace(void) for (i = 0; i < acpi_gbl_root_table_list.current_table_count; ++i) { table = &acpi_gbl_root_table_list.tables[i]; - if (!acpi_gbl_root_table_list.tables[i].address || + if (!table->address || (!ACPI_COMPARE_NAME(table->signature.ascii, ACPI_SIG_SSDT) && !ACPI_COMPARE_NAME(table->signature.ascii, ACPI_SIG_PSDT) -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
