In acpi_initrd_override(), it checks several things to ensure the table it found is valid. In later patches, we need to do these check somewhere else. So this patch introduces a common function acpi_verify_table() to do all these checks, and reuse it in different places. The function will be used in the subsequent patches. Signed-off-by: Tang Chen <tangchen@xxxxxxxxxxxxxx> Reviewed-by: Zhang Yanfei <zhangyanfei@xxxxxxxxxxxxxx> Acked-by: Toshi Kani <toshi.kani@xxxxxx> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> --- drivers/acpi/osl.c | 86 +++++++++++++++++++++++++++++++++++++--------------- 1 files changed, 61 insertions(+), 25 deletions(-) diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index 3b8bab2..0043e9f 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -572,9 +572,68 @@ static const char * const table_sigs[] = { /* Must not increase 10 or needs code modification below */ #define ACPI_OVERRIDE_TABLES 10 +/******************************************************************************* + * + * FUNCTION: acpi_verify_table + * + * PARAMETERS: File - The initrd file + * Path - Path to acpi overriding tables in cpio file + * Signature - Signature of the table + * + * RETURN: 0 if it passes all the checks, -EINVAL if any check fails. + * + * DESCRIPTION: Check if an acpi table found in initrd is invalid. + * @signature can be NULL. If it is NULL, the function will check + * if the table signature matches any signature in table_sigs[]. + * + ******************************************************************************/ +int __init acpi_verify_table(struct cpio_data *file, + const char *path, const char *signature) +{ + int idx; + struct acpi_table_header *table = file->data; + + if (file->size < sizeof(struct acpi_table_header)) { + ACPI_INVALID_TABLE("Table smaller than ACPI header", + path, file->name); + return -EINVAL; + } + + if (signature) { + if (memcmp(table->signature, signature, 4)) { + ACPI_INVALID_TABLE("Table signature does not match", + path, file->name); + return -EINVAL; + } + } else { + for (idx = 0; table_sigs[idx]; idx++) + if (!memcmp(table->signature, table_sigs[idx], 4)) + break; + + if (!table_sigs[idx]) { + ACPI_INVALID_TABLE("Unknown signature", path, file->name); + return -EINVAL; + } + } + + if (file->size != table->length) { + ACPI_INVALID_TABLE("File length does not match table length", + path, file->name); + return -EINVAL; + } + + if (acpi_table_checksum(file->data, table->length)) { + ACPI_INVALID_TABLE("Bad table checksum", + path, file->name); + return -EINVAL; + } + + return 0; +} + void __init acpi_initrd_override(void *data, size_t size) { - int sig, no, table_nr = 0, total_offset = 0; + int no, table_nr = 0, total_offset = 0; long offset = 0; struct acpi_table_header *table; char cpio_path[32] = "kernel/firmware/acpi/"; @@ -593,33 +652,10 @@ void __init acpi_initrd_override(void *data, size_t size) data += offset; size -= offset; - if (file.size < sizeof(struct acpi_table_header)) { - ACPI_INVALID_TABLE("Table smaller than ACPI header", - cpio_path, file.name); - continue; - } - table = file.data; - for (sig = 0; table_sigs[sig]; sig++) - if (!memcmp(table->signature, table_sigs[sig], 4)) - break; - - if (!table_sigs[sig]) { - ACPI_INVALID_TABLE("Unknown signature", - cpio_path, file.name); + if (acpi_verify_table(&file, cpio_path, NULL)) continue; - } - if (file.size != table->length) { - ACPI_INVALID_TABLE("File length does not match table length", - cpio_path, file.name); - continue; - } - if (acpi_table_checksum(file.data, table->length)) { - ACPI_INVALID_TABLE("Bad table checksum", - cpio_path, file.name); - continue; - } pr_info("%4.4s ACPI table found in initrd [%s%s][0x%x]\n", table->signature, cpio_path, file.name, table->length); -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html