[PATCH 3.19 138/177] firmware: dmi_scan: Fix dmi_len type

Greg Kroah-Hartman
2015-03-16T15:31:03Z

From: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>

commit 6d9ff473317245e3e5cd9922b4520411c2296388 upstream.

According to SMBIOSv3 specification the length of DMI table can be
up to 32bits wide. So use appropriate type to avoid overflow.

It's obvious that dmi_num theoretically can be more than u16 also,
so it's can be changed to u32 or at least it's better to use int
instead of u16, but on that moment I cannot imagine dmi structure
count more than 65535 and it can require changing type of vars that
work with it. So I didn't correct it.

Acked-by: Ard Biesheuvel <ard@linaro.org>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/firmware/dmi_scan.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/firmware/dmi_scan.c
+++ b/drivers/firmware/dmi_scan.c
@@ -78,7 +78,7 @@ static const char * __init dmi_string(co
* We have to be cautious here. We have seen BIOSes with DMI pointers
* pointing to completely the wrong place for example
*/
-static void dmi_table(u8 *buf, int len, int num,
+static void dmi_table(u8 *buf, u32 len, int num,
void (*decode)(const struct dmi_header *, void *),
void *private_data)
{
@@ -114,7 +114,7 @@ static void dmi_table(u8 *buf, int len,
}

static phys_addr_t dmi_base;
-static u16 dmi_len;
+static u32 dmi_len;
static u16 dmi_num;

static int __init dmi_walk_early(void (*decode)(const struct dmi_header *,