diff options
-rw-r--r-- | drivers/firmware/dmi_scan.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c index eb760a218da4..232fa8fce26a 100644 --- a/drivers/firmware/dmi_scan.c +++ b/drivers/firmware/dmi_scan.c @@ -419,6 +419,13 @@ static void __init dmi_format_ids(char *buf, size_t len) dmi_get_system_info(DMI_BIOS_DATE)); } +/* + * Check for DMI/SMBIOS headers in the system firmware image. Any + * SMBIOS header must start 16 bytes before the DMI header, so take a + * 32 byte buffer and check for DMI at offset 16 and SMBIOS at offset + * 0. If the DMI header is present, set dmi_ver accordingly (SMBIOS + * takes precedence) and return 0. Otherwise return 1. + */ static int __init dmi_present(const u8 *buf) { int smbios_ver; @@ -506,6 +513,13 @@ void __init dmi_scan_machine(void) if (p == NULL) goto error; + /* + * Iterate over all possible DMI header addresses q. + * Maintain the 32 bytes around q in buf. On the + * first iteration, substitute zero for the + * out-of-range bytes so there is no chance of falsely + * detecting an SMBIOS header. + */ memset(buf, 0, 16); for (q = p; q < p + 0x10000; q += 16) { memcpy_fromio(buf + 16, q, 16); |