MIPS: BCM63XX: fix nvram checksum calculation

The current checksum calculation code does nothing except checking that
the first byte of nvram is 0 without actually checking the checksum.

Implement the correct checksum calculation by calculating the crc32 with
the checksum field set to 0.

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>
Patchwork: http://patchwork.linux-mips.org/patch/4540
This commit is contained in:
Jonas Gorski 2012-11-11 12:22:34 +00:00 committed by John Crispin
parent 2da4c74dc3
commit ce8f0d0607

View File

@ -11,6 +11,7 @@
#define pr_fmt(fmt) "bcm63xx_nvram: " fmt
#include <linux/init.h>
#include <linux/crc32.h>
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/if_ether.h>
@ -40,23 +41,25 @@ static int mac_addr_used;
int __init bcm63xx_nvram_init(void *addr)
{
unsigned int check_len;
u8 *p;
u32 val;
u32 crc, expected_crc;
/* extract nvram data */
memcpy(&nvram, addr, sizeof(nvram));
/* check checksum before using data */
if (nvram.version <= 4)
check_len = offsetof(struct bcm963xx_nvram, checksum_old);
else
if (nvram.version <= 4) {
check_len = offsetof(struct bcm963xx_nvram, reserved3);
expected_crc = nvram.checksum_old;
nvram.checksum_old = 0;
} else {
check_len = sizeof(nvram);
val = 0;
p = (u8 *)&nvram;
expected_crc = nvram.checksum_high;
nvram.checksum_high = 0;
}
while (check_len--)
val += *p;
if (val)
crc = crc32_le(~0, (u8 *)&nvram, check_len);
if (crc != expected_crc)
return -EINVAL;
return 0;