u-boot/common/env_sf.c
Rob Herring 60d7d5a631 env: fix potential stack overflow in environment functions
Most of the various environment functions create CONFIG_ENV_SIZE buffers on
the stack. At least on ARM and PPC which have 4KB stacks, this can overflow
the stack if we have large environment sizes. So move all the buffers off
the stack to static buffers.

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2013-04-02 16:23:34 -04:00

352 lines
8.2 KiB
C

/*
* (C) Copyright 2000-2010
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Andreas Heppel <aheppel@sysgo.de>
*
* (C) Copyright 2008 Atmel Corporation
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <environment.h>
#include <malloc.h>
#include <spi_flash.h>
#include <search.h>
#include <errno.h>
#ifndef CONFIG_ENV_SPI_BUS
# define CONFIG_ENV_SPI_BUS 0
#endif
#ifndef CONFIG_ENV_SPI_CS
# define CONFIG_ENV_SPI_CS 0
#endif
#ifndef CONFIG_ENV_SPI_MAX_HZ
# define CONFIG_ENV_SPI_MAX_HZ 1000000
#endif
#ifndef CONFIG_ENV_SPI_MODE
# define CONFIG_ENV_SPI_MODE SPI_MODE_3
#endif
#ifdef CONFIG_ENV_OFFSET_REDUND
static ulong env_offset = CONFIG_ENV_OFFSET;
static ulong env_new_offset = CONFIG_ENV_OFFSET_REDUND;
#define ACTIVE_FLAG 1
#define OBSOLETE_FLAG 0
#endif /* CONFIG_ENV_OFFSET_REDUND */
DECLARE_GLOBAL_DATA_PTR;
char *env_name_spec = "SPI Flash";
static struct spi_flash *env_flash;
static char env_buf[CONFIG_ENV_SIZE];
#if defined(CONFIG_ENV_OFFSET_REDUND)
int saveenv(void)
{
env_t *env_new = (env_t *)env_buf;
ssize_t len;
char *res, *saved_buffer = NULL, flag = OBSOLETE_FLAG;
u32 saved_size, saved_offset, sector = 1;
int ret;
if (!env_flash) {
env_flash = spi_flash_probe(CONFIG_ENV_SPI_BUS,
CONFIG_ENV_SPI_CS,
CONFIG_ENV_SPI_MAX_HZ, CONFIG_ENV_SPI_MODE);
if (!env_flash) {
set_default_env("!spi_flash_probe() failed");
return 1;
}
}
res = (char *)env_new->data;
len = hexport_r(&env_htab, '\0', 0, &res, ENV_SIZE, 0, NULL);
if (len < 0) {
error("Cannot export environment: errno = %d\n", errno);
return 1;
}
env_new->crc = crc32(0, env_new->data, ENV_SIZE);
env_new->flags = ACTIVE_FLAG;
if (gd->env_valid == 1) {
env_new_offset = CONFIG_ENV_OFFSET_REDUND;
env_offset = CONFIG_ENV_OFFSET;
} else {
env_new_offset = CONFIG_ENV_OFFSET;
env_offset = CONFIG_ENV_OFFSET_REDUND;
}
/* Is the sector larger than the env (i.e. embedded) */
if (CONFIG_ENV_SECT_SIZE > CONFIG_ENV_SIZE) {
saved_size = CONFIG_ENV_SECT_SIZE - CONFIG_ENV_SIZE;
saved_offset = env_new_offset + CONFIG_ENV_SIZE;
saved_buffer = malloc(saved_size);
if (!saved_buffer) {
ret = 1;
goto done;
}
ret = spi_flash_read(env_flash, saved_offset,
saved_size, saved_buffer);
if (ret)
goto done;
}
if (CONFIG_ENV_SIZE > CONFIG_ENV_SECT_SIZE) {
sector = CONFIG_ENV_SIZE / CONFIG_ENV_SECT_SIZE;
if (CONFIG_ENV_SIZE % CONFIG_ENV_SECT_SIZE)
sector++;
}
puts("Erasing SPI flash...");
ret = spi_flash_erase(env_flash, env_new_offset,
sector * CONFIG_ENV_SECT_SIZE);
if (ret)
goto done;
puts("Writing to SPI flash...");
ret = spi_flash_write(env_flash, env_new_offset,
CONFIG_ENV_SIZE, env_new);
if (ret)
goto done;
if (CONFIG_ENV_SECT_SIZE > CONFIG_ENV_SIZE) {
ret = spi_flash_write(env_flash, saved_offset,
saved_size, saved_buffer);
if (ret)
goto done;
}
ret = spi_flash_write(env_flash, env_offset + offsetof(env_t, flags),
sizeof(env_new->flags), &flag);
if (ret)
goto done;
puts("done\n");
gd->env_valid = gd->env_valid == 2 ? 1 : 2;
printf("Valid environment: %d\n", (int)gd->env_valid);
done:
if (saved_buffer)
free(saved_buffer);
return ret;
}
void env_relocate_spec(void)
{
int ret;
int crc1_ok = 0, crc2_ok = 0;
env_t *tmp_env1 = NULL;
env_t *tmp_env2 = NULL;
env_t *ep = NULL;
tmp_env1 = (env_t *)malloc(CONFIG_ENV_SIZE);
tmp_env2 = (env_t *)malloc(CONFIG_ENV_SIZE);
if (!tmp_env1 || !tmp_env2) {
set_default_env("!malloc() failed");
goto out;
}
env_flash = spi_flash_probe(CONFIG_ENV_SPI_BUS, CONFIG_ENV_SPI_CS,
CONFIG_ENV_SPI_MAX_HZ, CONFIG_ENV_SPI_MODE);
if (!env_flash) {
set_default_env("!spi_flash_probe() failed");
goto out;
}
ret = spi_flash_read(env_flash, CONFIG_ENV_OFFSET,
CONFIG_ENV_SIZE, tmp_env1);
if (ret) {
set_default_env("!spi_flash_read() failed");
goto err_read;
}
if (crc32(0, tmp_env1->data, ENV_SIZE) == tmp_env1->crc)
crc1_ok = 1;
ret = spi_flash_read(env_flash, CONFIG_ENV_OFFSET_REDUND,
CONFIG_ENV_SIZE, tmp_env2);
if (!ret) {
if (crc32(0, tmp_env2->data, ENV_SIZE) == tmp_env2->crc)
crc2_ok = 1;
}
if (!crc1_ok && !crc2_ok) {
set_default_env("!bad CRC");
goto err_read;
} else if (crc1_ok && !crc2_ok) {
gd->env_valid = 1;
} else if (!crc1_ok && crc2_ok) {
gd->env_valid = 2;
} else if (tmp_env1->flags == ACTIVE_FLAG &&
tmp_env2->flags == OBSOLETE_FLAG) {
gd->env_valid = 1;
} else if (tmp_env1->flags == OBSOLETE_FLAG &&
tmp_env2->flags == ACTIVE_FLAG) {
gd->env_valid = 2;
} else if (tmp_env1->flags == tmp_env2->flags) {
gd->env_valid = 2;
} else if (tmp_env1->flags == 0xFF) {
gd->env_valid = 2;
} else {
/*
* this differs from code in env_flash.c, but I think a sane
* default path is desirable.
*/
gd->env_valid = 2;
}
if (gd->env_valid == 1)
ep = tmp_env1;
else
ep = tmp_env2;
ret = env_import((char *)ep, 0);
if (!ret) {
error("Cannot import environment: errno = %d\n", errno);
set_default_env("env_import failed");
}
err_read:
spi_flash_free(env_flash);
env_flash = NULL;
out:
free(tmp_env1);
free(tmp_env2);
}
#else
int saveenv(void)
{
u32 saved_size, saved_offset, sector = 1;
char *res, *saved_buffer = NULL;
int ret = 1;
env_t *env_new = (env_t *)env_buf;
ssize_t len;
if (!env_flash) {
env_flash = spi_flash_probe(CONFIG_ENV_SPI_BUS,
CONFIG_ENV_SPI_CS,
CONFIG_ENV_SPI_MAX_HZ, CONFIG_ENV_SPI_MODE);
if (!env_flash) {
set_default_env("!spi_flash_probe() failed");
return 1;
}
}
/* Is the sector larger than the env (i.e. embedded) */
if (CONFIG_ENV_SECT_SIZE > CONFIG_ENV_SIZE) {
saved_size = CONFIG_ENV_SECT_SIZE - CONFIG_ENV_SIZE;
saved_offset = CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE;
saved_buffer = malloc(saved_size);
if (!saved_buffer)
goto done;
ret = spi_flash_read(env_flash, saved_offset,
saved_size, saved_buffer);
if (ret)
goto done;
}
if (CONFIG_ENV_SIZE > CONFIG_ENV_SECT_SIZE) {
sector = CONFIG_ENV_SIZE / CONFIG_ENV_SECT_SIZE;
if (CONFIG_ENV_SIZE % CONFIG_ENV_SECT_SIZE)
sector++;
}
res = (char *)env_new->data;
len = hexport_r(&env_htab, '\0', 0, &res, ENV_SIZE, 0, NULL);
if (len < 0) {
error("Cannot export environment: errno = %d\n", errno);
goto done;
}
env_new->crc = crc32(0, env_new->data, ENV_SIZE);
puts("Erasing SPI flash...");
ret = spi_flash_erase(env_flash, CONFIG_ENV_OFFSET,
sector * CONFIG_ENV_SECT_SIZE);
if (ret)
goto done;
puts("Writing to SPI flash...");
ret = spi_flash_write(env_flash, CONFIG_ENV_OFFSET,
CONFIG_ENV_SIZE, env_new);
if (ret)
goto done;
if (CONFIG_ENV_SECT_SIZE > CONFIG_ENV_SIZE) {
ret = spi_flash_write(env_flash, saved_offset,
saved_size, saved_buffer);
if (ret)
goto done;
}
ret = 0;
puts("done\n");
done:
if (saved_buffer)
free(saved_buffer);
return ret;
}
void env_relocate_spec(void)
{
char *buf = env_buf;
int ret;
env_flash = spi_flash_probe(CONFIG_ENV_SPI_BUS, CONFIG_ENV_SPI_CS,
CONFIG_ENV_SPI_MAX_HZ, CONFIG_ENV_SPI_MODE);
if (!env_flash) {
set_default_env("!spi_flash_probe() failed");
return;
}
ret = spi_flash_read(env_flash,
CONFIG_ENV_OFFSET, CONFIG_ENV_SIZE, buf);
if (ret) {
set_default_env("!spi_flash_read() failed");
goto out;
}
ret = env_import(buf, 1);
if (ret)
gd->env_valid = 1;
out:
spi_flash_free(env_flash);
env_flash = NULL;
}
#endif
int env_init(void)
{
/* SPI flash isn't usable before relocation */
gd->env_addr = (ulong)&default_environment[0];
gd->env_valid = 1;
return 0;
}