From 60d7d5a63189c9f77a190c9965861dc15482c2d0 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Fri, 22 Mar 2013 11:26:21 +0000 Subject: [PATCH] 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 --- common/env_dataflash.c | 15 +++++++-------- common/env_eeprom.c | 13 +++++++------ common/env_fat.c | 11 ++++++----- common/env_mmc.c | 13 +++++++------ common/env_nand.c | 23 ++++++++++++----------- common/env_nvram.c | 26 ++++++++++++++++---------- common/env_onenand.c | 13 +++++++------ common/env_sf.c | 23 ++++++++++++----------- 8 files changed, 74 insertions(+), 63 deletions(-) diff --git a/common/env_dataflash.c b/common/env_dataflash.c index 38c9615..0591b99 100644 --- a/common/env_dataflash.c +++ b/common/env_dataflash.c @@ -30,6 +30,7 @@ DECLARE_GLOBAL_DATA_PTR; env_t *env_ptr; char *env_name_spec = "dataflash"; +static char env_buf[CONFIG_ENV_SIZE]; uchar env_get_char_spec(int index) { @@ -42,11 +43,9 @@ uchar env_get_char_spec(int index) void env_relocate_spec(void) { - char buf[CONFIG_ENV_SIZE]; + read_dataflash(CONFIG_ENV_ADDR, CONFIG_ENV_SIZE, env_buf); - read_dataflash(CONFIG_ENV_ADDR, CONFIG_ENV_SIZE, buf); - - env_import(buf, 1); + env_import(env_buf, 1); } #ifdef CONFIG_ENV_OFFSET_REDUND @@ -55,20 +54,20 @@ void env_relocate_spec(void) int saveenv(void) { - env_t env_new; + env_t *env_new = (env_t *)env_buf; ssize_t len; char *res; - res = (char *)&env_new.data; + 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->crc = crc32(0, env_new->data, ENV_SIZE); return write_dataflash(CONFIG_ENV_ADDR, - (unsigned long)&env_new, + (unsigned long)env_new, CONFIG_ENV_SIZE); } diff --git a/common/env_eeprom.c b/common/env_eeprom.c index 45c935b..b136f04 100644 --- a/common/env_eeprom.c +++ b/common/env_eeprom.c @@ -38,6 +38,7 @@ DECLARE_GLOBAL_DATA_PTR; env_t *env_ptr; +static char env_buf[CONFIG_ENV_SIZE]; char *env_name_spec = "EEPROM"; int env_eeprom_bus = -1; @@ -111,7 +112,7 @@ uchar env_get_char_spec(int index) void env_relocate_spec(void) { - char buf[CONFIG_ENV_SIZE]; + char *buf = env_buf; unsigned int off = CONFIG_ENV_OFFSET; #ifdef CONFIG_ENV_OFFSET_REDUND @@ -126,7 +127,7 @@ void env_relocate_spec(void) int saveenv(void) { - env_t env_new; + env_t *env_new = (env_t *)env_buf; ssize_t len; char *res; int rc; @@ -138,13 +139,13 @@ int saveenv(void) BUG_ON(env_ptr != NULL); - res = (char *)&env_new.data; + 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->crc = crc32(0, env_new->data, ENV_SIZE); #ifdef CONFIG_ENV_OFFSET_REDUND if (gd->env_valid == 1) { @@ -152,11 +153,11 @@ int saveenv(void) off_red = CONFIG_ENV_OFFSET; } - env_new.flags = ACTIVE_FLAG; + env_new->flags = ACTIVE_FLAG; #endif rc = eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR, - off, (uchar *)&env_new, CONFIG_ENV_SIZE); + off, (uchar *)env_new, CONFIG_ENV_SIZE); #ifdef CONFIG_ENV_OFFSET_REDUND if (rc == 0) { diff --git a/common/env_fat.c b/common/env_fat.c index c0f18ab..dd7139d 100644 --- a/common/env_fat.c +++ b/common/env_fat.c @@ -37,6 +37,7 @@ char *env_name_spec = "FAT"; env_t *env_ptr; +static char env_buf[CONFIG_ENV_SIZE]; DECLARE_GLOBAL_DATA_PTR; @@ -52,7 +53,7 @@ int env_init(void) #ifdef CONFIG_CMD_SAVEENV int saveenv(void) { - env_t env_new; + env_t *env_new = env_buf; ssize_t len; char *res; block_dev_desc_t *dev_desc = NULL; @@ -60,7 +61,7 @@ int saveenv(void) int part = FAT_ENV_PART; int err; - res = (char *)&env_new.data; + 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); @@ -95,8 +96,8 @@ int saveenv(void) return 1; } - env_new.crc = crc32(0, env_new.data, ENV_SIZE); - err = file_fat_write(FAT_ENV_FILE, (void *)&env_new, sizeof(env_t)); + env_new->crc = crc32(0, env_new->data, ENV_SIZE); + err = file_fat_write(FAT_ENV_FILE, (void *)env_new, sizeof(env_t)); if (err == -1) { printf("\n** Unable to write \"%s\" from %s%d:%d **\n", FAT_ENV_FILE, FAT_ENV_INTERFACE, dev, part); @@ -110,7 +111,7 @@ int saveenv(void) void env_relocate_spec(void) { - char buf[CONFIG_ENV_SIZE]; + char *buf = env_buf; block_dev_desc_t *dev_desc = NULL; int dev = FAT_ENV_DEVICE; int part = FAT_ENV_PART; diff --git a/common/env_mmc.c b/common/env_mmc.c index 02bd5ae..f568013 100644 --- a/common/env_mmc.c +++ b/common/env_mmc.c @@ -40,6 +40,8 @@ env_t *env_ptr = &environment; env_t *env_ptr; #endif /* ENV_IS_EMBEDDED */ +DEFINE_CACHE_ALIGN_BUFFER(char, env_buf, CONFIG_ENV_SIZE); + DECLARE_GLOBAL_DATA_PTR; #if !defined(CONFIG_ENV_OFFSET) @@ -112,7 +114,7 @@ static inline int write_env(struct mmc *mmc, unsigned long size, int saveenv(void) { - ALLOC_CACHE_ALIGN_BUFFER(env_t, env_new, 1); + env_t *env_new = (env_t *)env_buf; ssize_t len; char *res; struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV); @@ -127,7 +129,7 @@ int saveenv(void) goto fini; } - res = (char *)&env_new->data; + 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); @@ -135,7 +137,7 @@ int saveenv(void) goto fini; } - env_new->crc = crc32(0, &env_new->data[0], ENV_SIZE); + env_new->crc = crc32(0, env_new->data, ENV_SIZE); printf("Writing to MMC(%d)... ", CONFIG_SYS_MMC_ENV_DEV); if (write_env(mmc, CONFIG_ENV_SIZE, offset, (u_char *)env_new)) { puts("failed\n"); @@ -169,7 +171,6 @@ static inline int read_env(struct mmc *mmc, unsigned long size, void env_relocate_spec(void) { #if !defined(ENV_IS_EMBEDDED) - ALLOC_CACHE_ALIGN_BUFFER(char, buf, CONFIG_ENV_SIZE); struct mmc *mmc = find_mmc_device(CONFIG_SYS_MMC_ENV_DEV); u32 offset; int ret; @@ -184,12 +185,12 @@ void env_relocate_spec(void) goto fini; } - if (read_env(mmc, CONFIG_ENV_SIZE, offset, buf)) { + if (read_env(mmc, CONFIG_ENV_SIZE, offset, env_buf)) { ret = 1; goto fini; } - env_import(buf, 1); + env_import(env_buf, 1); ret = 0; fini: diff --git a/common/env_nand.c b/common/env_nand.c index 5b69889..8cc2055 100644 --- a/common/env_nand.c +++ b/common/env_nand.c @@ -64,6 +64,8 @@ env_t *env_ptr = (env_t *)CONFIG_NAND_ENV_DST; env_t *env_ptr; #endif /* ENV_IS_EMBEDDED */ +DEFINE_CACHE_ALIGN_BUFFER(char, env_buf, CONFIG_ENV_SIZE); + DECLARE_GLOBAL_DATA_PTR; /* @@ -173,7 +175,7 @@ static unsigned char env_flags; int saveenv(void) { - env_t env_new; + env_t *env_new = (env_t *)env_buf; ssize_t len; char *res; int ret = 0; @@ -185,14 +187,14 @@ int saveenv(void) if (CONFIG_ENV_RANGE < CONFIG_ENV_SIZE) return 1; - res = (char *)&env_new.data; + 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 = ++env_flags; /* increase the serial */ + env_new->crc = crc32(0, env_new->data, ENV_SIZE); + env_new->flags = ++env_flags; /* increase the serial */ if (gd->env_valid == 1) { puts("Erasing redundant NAND...\n"); @@ -201,7 +203,7 @@ int saveenv(void) return 1; puts("Writing to redundant NAND... "); - ret = writeenv(CONFIG_ENV_OFFSET_REDUND, (u_char *)&env_new); + ret = writeenv(CONFIG_ENV_OFFSET_REDUND, (u_char *)env_new); } else { puts("Erasing NAND...\n"); nand_erase_options.offset = CONFIG_ENV_OFFSET; @@ -209,7 +211,7 @@ int saveenv(void) return 1; puts("Writing to NAND... "); - ret = writeenv(CONFIG_ENV_OFFSET, (u_char *)&env_new); + ret = writeenv(CONFIG_ENV_OFFSET, (u_char *)env_new); } if (ret) { puts("FAILED!\n"); @@ -226,7 +228,7 @@ int saveenv(void) int saveenv(void) { int ret = 0; - ALLOC_CACHE_ALIGN_BUFFER(env_t, env_new, 1); + env_t *env_new = (env_t *)env_buf; ssize_t len; char *res; nand_erase_options_t nand_erase_options; @@ -238,7 +240,7 @@ int saveenv(void) if (CONFIG_ENV_RANGE < CONFIG_ENV_SIZE) return 1; - res = (char *)&env_new->data; + 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); @@ -404,7 +406,6 @@ void env_relocate_spec(void) { #if !defined(ENV_IS_EMBEDDED) int ret; - ALLOC_CACHE_ALIGN_BUFFER(char, buf, CONFIG_ENV_SIZE); #if defined(CONFIG_ENV_OFFSET_OOB) ret = get_nand_env_oob(&nand_info[0], &nand_env_oob_offset); @@ -420,13 +421,13 @@ void env_relocate_spec(void) } #endif - ret = readenv(CONFIG_ENV_OFFSET, (u_char *)buf); + ret = readenv(CONFIG_ENV_OFFSET, (u_char *)env_buf); if (ret) { set_default_env("!readenv() failed"); return; } - env_import(buf, 1); + env_import(env_buf, 1); #endif /* ! ENV_IS_EMBEDDED */ } #endif /* CONFIG_ENV_OFFSET_REDUND */ diff --git a/common/env_nvram.c b/common/env_nvram.c index eab0e7b..ff74a6c 100644 --- a/common/env_nvram.c +++ b/common/env_nvram.c @@ -60,6 +60,10 @@ env_t *env_ptr = (env_t *)CONFIG_ENV_ADDR; char *env_name_spec = "NVRAM"; #ifdef CONFIG_SYS_NVRAM_ACCESS_ROUTINE +static char env_buf[CONFIG_ENV_SIZE]; +#endif + +#ifdef CONFIG_SYS_NVRAM_ACCESS_ROUTINE uchar env_get_char_spec(int index) { uchar c; @@ -72,36 +76,38 @@ uchar env_get_char_spec(int index) void env_relocate_spec(void) { - char buf[CONFIG_ENV_SIZE]; + char *buf; #if defined(CONFIG_SYS_NVRAM_ACCESS_ROUTINE) + buf = env_buf; nvram_read(buf, CONFIG_ENV_ADDR, CONFIG_ENV_SIZE); #else - memcpy(buf, (void *)CONFIG_ENV_ADDR, CONFIG_ENV_SIZE); + buf = (void *)CONFIG_ENV_ADDR; #endif env_import(buf, 1); } int saveenv(void) { - env_t env_new; +#ifdef CONFIG_SYS_NVRAM_ACCESS_ROUTINE + env_t *env_new = (env_t *)env_buf; +#else + env_t *env_new = (env_t *)CONFIG_ENV_ADDR; +#endif ssize_t len; char *res; int rcode = 0; - res = (char *)&env_new.data; + 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->crc = crc32(0, env_new->data, ENV_SIZE); #ifdef CONFIG_SYS_NVRAM_ACCESS_ROUTINE - nvram_write(CONFIG_ENV_ADDR, &env_new, CONFIG_ENV_SIZE); -#else - if (memcpy((char *)CONFIG_ENV_ADDR, &env_new, CONFIG_ENV_SIZE) == NULL) - rcode = 1; + nvram_write(CONFIG_ENV_ADDR, env_new, CONFIG_ENV_SIZE); #endif return rcode; } @@ -115,7 +121,7 @@ int env_init(void) { #if defined(CONFIG_SYS_NVRAM_ACCESS_ROUTINE) ulong crc; - uchar data[ENV_SIZE]; + uchar *data = env_buf; nvram_read(&crc, CONFIG_ENV_ADDR, sizeof(ulong)); nvram_read(data, CONFIG_ENV_ADDR + sizeof(ulong), ENV_SIZE); diff --git a/common/env_onenand.c b/common/env_onenand.c index faa903d..6fd5613 100644 --- a/common/env_onenand.c +++ b/common/env_onenand.c @@ -42,6 +42,8 @@ char *env_name_spec = "OneNAND"; #define ONENAND_MAX_ENV_SIZE CONFIG_ENV_SIZE #define ONENAND_ENV_SIZE(mtd) (ONENAND_MAX_ENV_SIZE - ENV_HEADER_SIZE) +static char env_buf[CONFIG_ENV_SIZE]; + DECLARE_GLOBAL_DATA_PTR; void env_relocate_spec(void) @@ -56,8 +58,7 @@ void env_relocate_spec(void) char *buf = (char *)&environment; #else loff_t env_addr = CONFIG_ENV_ADDR; - char onenand_env[ONENAND_MAX_ENV_SIZE]; - char *buf = (char *)&onenand_env[0]; + char *buf = env_buf; #endif /* ENV_IS_EMBEDDED */ #ifndef ENV_IS_EMBEDDED @@ -81,7 +82,7 @@ void env_relocate_spec(void) int saveenv(void) { - env_t env_new; + env_t *env_new = env_buf; ssize_t len; char *res; struct mtd_info *mtd = &onenand_mtd; @@ -94,13 +95,13 @@ int saveenv(void) .callback = NULL, }; - res = (char *)&env_new.data; + 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->crc = crc32(0, env_new->data, ENV_SIZE); instr.len = CONFIG_ENV_SIZE; #ifdef CONFIG_ENV_ADDR_FLEX @@ -119,7 +120,7 @@ int saveenv(void) } if (mtd->write(mtd, env_addr, ONENAND_MAX_ENV_SIZE, &retlen, - (u_char *)&env_new)) { + (u_char *)env_new)) { printf("OneNAND: write failed at 0x%llx\n", instr.addr); return 2; } diff --git a/common/env_sf.c b/common/env_sf.c index d9e9085..9a592ba 100644 --- a/common/env_sf.c +++ b/common/env_sf.c @@ -58,11 +58,12 @@ 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_new = (env_t *)env_buf; ssize_t len; char *res, *saved_buffer = NULL, flag = OBSOLETE_FLAG; u32 saved_size, saved_offset, sector = 1; @@ -78,14 +79,14 @@ int saveenv(void) } } - res = (char *)&env_new.data; + 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; + 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; @@ -125,7 +126,7 @@ int saveenv(void) puts("Writing to SPI flash..."); ret = spi_flash_write(env_flash, env_new_offset, - CONFIG_ENV_SIZE, &env_new); + CONFIG_ENV_SIZE, env_new); if (ret) goto done; @@ -137,7 +138,7 @@ int saveenv(void) } ret = spi_flash_write(env_flash, env_offset + offsetof(env_t, flags), - sizeof(env_new.flags), &flag); + sizeof(env_new->flags), &flag); if (ret) goto done; @@ -243,7 +244,7 @@ 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_new = (env_t *)env_buf; ssize_t len; if (!env_flash) { @@ -276,13 +277,13 @@ int saveenv(void) sector++; } - res = (char *)&env_new.data; + 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); + env_new->crc = crc32(0, env_new->data, ENV_SIZE); puts("Erasing SPI flash..."); ret = spi_flash_erase(env_flash, CONFIG_ENV_OFFSET, @@ -292,7 +293,7 @@ int saveenv(void) puts("Writing to SPI flash..."); ret = spi_flash_write(env_flash, CONFIG_ENV_OFFSET, - CONFIG_ENV_SIZE, &env_new); + CONFIG_ENV_SIZE, env_new); if (ret) goto done; @@ -315,7 +316,7 @@ int saveenv(void) void env_relocate_spec(void) { - char buf[CONFIG_ENV_SIZE]; + char *buf = env_buf; int ret; env_flash = spi_flash_probe(CONFIG_ENV_SPI_BUS, CONFIG_ENV_SPI_CS,