diff options
Diffstat (limited to 'drivers/acpi')
| -rw-r--r-- | drivers/acpi/acpica/tbutils.c | 210 |
1 files changed, 120 insertions, 90 deletions
diff --git a/drivers/acpi/acpica/tbutils.c b/drivers/acpi/acpica/tbutils.c index 3d6bb83aa7e7..ee6067062cdc 100644 --- a/drivers/acpi/acpica/tbutils.c +++ b/drivers/acpi/acpica/tbutils.c @@ -49,69 +49,11 @@ ACPI_MODULE_NAME("tbutils") /* Local prototypes */ +static acpi_status acpi_tb_validate_xsdt(acpi_physical_address address); + static acpi_physical_address acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size); -/******************************************************************************* - * - * FUNCTION: acpi_tb_check_xsdt - * - * PARAMETERS: address - Pointer to the XSDT - * - * RETURN: status - * AE_OK - XSDT is okay - * AE_NO_MEMORY - can't map XSDT - * AE_INVALID_TABLE_LENGTH - invalid table length - * AE_NULL_ENTRY - XSDT has NULL entry - * - * DESCRIPTION: validate XSDT -******************************************************************************/ - -static acpi_status -acpi_tb_check_xsdt(acpi_physical_address address) -{ - struct acpi_table_header *table; - u32 length; - u64 xsdt_entry_address; - u8 *table_entry; - u32 table_count; - int i; - - table = acpi_os_map_memory(address, sizeof(struct acpi_table_header)); - if (!table) - return AE_NO_MEMORY; - - length = table->length; - acpi_os_unmap_memory(table, sizeof(struct acpi_table_header)); - if (length < sizeof(struct acpi_table_header)) - return AE_INVALID_TABLE_LENGTH; - - table = acpi_os_map_memory(address, length); - if (!table) - return AE_NO_MEMORY; - - /* Calculate the number of tables described in XSDT */ - table_count = - (u32) ((table->length - - sizeof(struct acpi_table_header)) / sizeof(u64)); - table_entry = - ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header); - for (i = 0; i < table_count; i++) { - ACPI_MOVE_64_TO_64(&xsdt_entry_address, table_entry); - if (!xsdt_entry_address) { - /* XSDT has NULL entry */ - break; - } - table_entry += sizeof(u64); - } - acpi_os_unmap_memory(table, length); - - if (i < table_count) - return AE_NULL_ENTRY; - else - return AE_OK; -} - #if (!ACPI_REDUCED_HARDWARE) /******************************************************************************* * @@ -383,7 +325,7 @@ acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size) * Get the table physical address (32-bit for RSDT, 64-bit for XSDT): * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT */ - if (table_entry_size == sizeof(u32)) { + if (table_entry_size == ACPI_RSDT_ENTRY_SIZE) { /* * 32-bit platform, RSDT: Return 32-bit table entry * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return @@ -415,6 +357,87 @@ acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size) /******************************************************************************* * + * FUNCTION: acpi_tb_validate_xsdt + * + * PARAMETERS: address - Physical address of the XSDT (from RSDP) + * + * RETURN: Status. AE_OK if the table appears to be valid. + * + * DESCRIPTION: Validate an XSDT to ensure that it is of minimum size and does + * not contain any NULL entries. A problem that is seen in the + * field is that the XSDT exists, but is actually useless because + * of one or more (or all) NULL entries. + * + ******************************************************************************/ + +static acpi_status acpi_tb_validate_xsdt(acpi_physical_address xsdt_address) +{ + struct acpi_table_header *table; + u8 *next_entry; + acpi_physical_address address; + u32 length; + u32 entry_count; + acpi_status status; + u32 i; + + /* Get the XSDT length */ + + table = + acpi_os_map_memory(xsdt_address, sizeof(struct acpi_table_header)); + if (!table) { + return (AE_NO_MEMORY); + } + + length = table->length; + acpi_os_unmap_memory(table, sizeof(struct acpi_table_header)); + + /* + * Minimum XSDT length is the size of the standard ACPI header + * plus one physical address entry + */ + if (length < (sizeof(struct acpi_table_header) + ACPI_XSDT_ENTRY_SIZE)) { + return (AE_INVALID_TABLE_LENGTH); + } + + /* Map the entire XSDT */ + + table = acpi_os_map_memory(xsdt_address, length); + if (!table) { + return (AE_NO_MEMORY); + } + + /* Get the number of entries and pointer to first entry */ + + status = AE_OK; + next_entry = ACPI_ADD_PTR(u8, table, sizeof(struct acpi_table_header)); + entry_count = (u32)((table->length - sizeof(struct acpi_table_header)) / + ACPI_XSDT_ENTRY_SIZE); + + /* Validate each entry (physical address) within the XSDT */ + + for (i = 0; i < entry_count; i++) { + address = + acpi_tb_get_root_table_entry(next_entry, + ACPI_XSDT_ENTRY_SIZE); + if (!address) { + + /* Detected a NULL entry, XSDT is invalid */ + + status = AE_NULL_ENTRY; + break; + } + + next_entry += ACPI_XSDT_ENTRY_SIZE; + } + + /* Unmap table */ + + acpi_os_unmap_memory(table, length); + return (status); +} + +/******************************************************************************* + * * FUNCTION: acpi_tb_parse_root_table * * PARAMETERS: rsdp - Pointer to the RSDP @@ -438,16 +461,14 @@ acpi_status __init acpi_tb_parse_root_table(acpi_physical_address rsdp_address) u32 table_count; struct acpi_table_header *table; acpi_physical_address address; - acpi_physical_address uninitialized_var(rsdt_address); u32 length; u8 *table_entry; acpi_status status; ACPI_FUNCTION_TRACE(tb_parse_root_table); - /* - * Map the entire RSDP and extract the address of the RSDT or XSDT - */ + /* Map the entire RSDP and extract the address of the RSDT or XSDT */ + rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp)); if (!rsdp) { return_ACPI_STATUS(AE_NO_MEMORY); @@ -459,22 +480,20 @@ acpi_status __init acpi_tb_parse_root_table(acpi_physical_address rsdp_address) /* Differentiate between RSDT and XSDT root tables */ - if (rsdp->revision > 1 && rsdp->xsdt_physical_address + if ((rsdp->revision > 1) && rsdp->xsdt_physical_address && !acpi_rsdt_forced) { /* - * Root table is an XSDT (64-bit physical addresses). We must use the - * XSDT if the revision is > 1 and the XSDT pointer is present, as per - * the ACPI specification. + * RSDP contains an XSDT (64-bit physical addresses). We must use + * the XSDT if the revision is > 1 and the XSDT pointer is present, + * as per the ACPI specification. */ address = (acpi_physical_address) rsdp->xsdt_physical_address; - table_entry_size = sizeof(u64); - rsdt_address = (acpi_physical_address) - rsdp->rsdt_physical_address; + table_entry_size = ACPI_XSDT_ENTRY_SIZE; } else { /* Root table is an RSDT (32-bit physical addresses) */ address = (acpi_physical_address) rsdp->rsdt_physical_address; - table_entry_size = sizeof(u32); + table_entry_size = ACPI_RSDT_ENTRY_SIZE; } /* @@ -483,15 +502,25 @@ acpi_status __init acpi_tb_parse_root_table(acpi_physical_address rsdp_address) */ acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp)); - if (table_entry_size == sizeof(u64)) { - if (acpi_tb_check_xsdt(address) == AE_NULL_ENTRY) { - /* XSDT has NULL entry, RSDT is used */ - address = rsdt_address; - table_entry_size = sizeof(u32); - ACPI_WARNING((AE_INFO, "BIOS XSDT has NULL entry, " - "using RSDT")); + /* + * If it is present, validate the XSDT for access/size and ensure + * that all table entries are at least non-NULL + */ + if (table_entry_size == ACPI_XSDT_ENTRY_SIZE) { + status = acpi_tb_validate_xsdt(address); + if (ACPI_FAILURE(status)) { + ACPI_BIOS_WARNING((AE_INFO, + "XSDT is invalid (%s), using RSDT", + acpi_format_exception(status))); + + /* Fall back to the RSDT */ + + address = + (acpi_physical_address) rsdp->rsdt_physical_address; + table_entry_size = ACPI_RSDT_ENTRY_SIZE; } } + /* Map the RSDT/XSDT table header to get the full table length */ table = acpi_os_map_memory(address, sizeof(struct acpi_table_header)); @@ -501,12 +530,14 @@ acpi_status __init acpi_tb_parse_root_table(acpi_physical_address rsdp_address) acpi_tb_print_table_header(address, table); - /* Get the length of the full table, verify length and map entire table */ - + /* + * Validate length of the table, and map entire table. + * Minimum length table must contain at least one entry. + */ length = table->length; acpi_os_unmap_memory(table, sizeof(struct acpi_table_header)); - if (length < sizeof(struct acpi_table_header)) { + if (length < (sizeof(struct acpi_table_header) + table_entry_size)) { ACPI_BIOS_ERROR((AE_INFO, "Invalid table length 0x%X in RSDT/XSDT", length)); @@ -526,22 +557,21 @@ acpi_status __init acpi_tb_parse_root_table(acpi_physical_address rsdp_address) return_ACPI_STATUS(status); } - /* Calculate the number of tables described in the root table */ + /* Get the number of entries and pointer to first entry */ table_count = (u32)((table->length - sizeof(struct acpi_table_header)) / table_entry_size); + table_entry = ACPI_ADD_PTR(u8, table, sizeof(struct acpi_table_header)); + /* * First two entries in the table array are reserved for the DSDT * and FACS, which are not actually present in the RSDT/XSDT - they * come from the FADT */ - table_entry = - ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header); acpi_gbl_root_table_list.current_table_count = 2; - /* - * Initialize the root table array from the RSDT/XSDT - */ + /* Initialize the root table array from the RSDT/XSDT */ + for (i = 0; i < table_count; i++) { if (acpi_gbl_root_table_list.current_table_count >= acpi_gbl_root_table_list.max_table_count) { @@ -584,7 +614,7 @@ acpi_status __init acpi_tb_parse_root_table(acpi_physical_address rsdp_address) acpi_tb_install_table(acpi_gbl_root_table_list.tables[i]. address, NULL, i); - /* Special case for FADT - get the DSDT and FACS */ + /* Special case for FADT - validate it then get the DSDT and FACS */ if (ACPI_COMPARE_NAME (&acpi_gbl_root_table_list.tables[i].signature, |
