| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * This file is part of UBIFS. |
| * |
| * Copyright (C) 2006-2008 Nokia Corporation. |
| * |
| * Authors: Artem Bityutskiy (Битюцкий Артём) |
| * Adrian Hunter |
| */ |
| |
| /* |
| * This file implements UBIFS superblock. The superblock is stored at the first |
| * LEB of the volume and is never changed by UBIFS. Only user-space tools may |
| * change it. The superblock node mostly contains geometry information. |
| */ |
| |
| #include "ubifs.h" |
| #include <linux/slab.h> |
| #include <linux/math64.h> |
| #include <linux/uuid.h> |
| |
| /* |
| * Default journal size in logical eraseblocks as a percent of total |
| * flash size. |
| */ |
| #define DEFAULT_JNL_PERCENT 5 |
| |
| /* Default maximum journal size in bytes */ |
| #define DEFAULT_MAX_JNL (32*1024*1024) |
| |
| /* Default indexing tree fanout */ |
| #define DEFAULT_FANOUT 8 |
| |
| /* Default number of data journal heads */ |
| #define DEFAULT_JHEADS_CNT 1 |
| |
| /* Default positions of different LEBs in the main area */ |
| #define DEFAULT_IDX_LEB 0 |
| #define DEFAULT_DATA_LEB 1 |
| #define DEFAULT_GC_LEB 2 |
| |
| /* Default number of LEB numbers in LPT's save table */ |
| #define DEFAULT_LSAVE_CNT 256 |
| |
| /* Default reserved pool size as a percent of maximum free space */ |
| #define DEFAULT_RP_PERCENT 5 |
| |
| /* The default maximum size of reserved pool in bytes */ |
| #define DEFAULT_MAX_RP_SIZE (5*1024*1024) |
| |
| /* Default time granularity in nanoseconds */ |
| #define DEFAULT_TIME_GRAN 1000000000 |
| |
| static int get_default_compressor(struct ubifs_info *c) |
| { |
| if (ubifs_compr_present(c, UBIFS_COMPR_LZO)) |
| return UBIFS_COMPR_LZO; |
| |
| if (ubifs_compr_present(c, UBIFS_COMPR_ZLIB)) |
| return UBIFS_COMPR_ZLIB; |
| |
| return UBIFS_COMPR_NONE; |
| } |
| |
| /** |
| * create_default_filesystem - format empty UBI volume. |
| * @c: UBIFS file-system description object |
| * |
| * This function creates default empty file-system. Returns zero in case of |
| * success and a negative error code in case of failure. |
| */ |
| static int create_default_filesystem(struct ubifs_info *c) |
| { |
| struct ubifs_sb_node *sup; |
| struct ubifs_mst_node *mst; |
| struct ubifs_idx_node *idx; |
| struct ubifs_branch *br; |
| struct ubifs_ino_node *ino; |
| struct ubifs_cs_node *cs; |
| union ubifs_key key; |
| int err, tmp, jnl_lebs, log_lebs, max_buds, main_lebs, main_first; |
| int lpt_lebs, lpt_first, orph_lebs, big_lpt, ino_waste, sup_flags = 0; |
| int min_leb_cnt = UBIFS_MIN_LEB_CNT; |
| int idx_node_size; |
| long long tmp64, main_bytes; |
| __le64 tmp_le64; |
| __le32 tmp_le32; |
| struct timespec64 ts; |
| u8 hash[UBIFS_HASH_ARR_SZ]; |
| u8 hash_lpt[UBIFS_HASH_ARR_SZ]; |
| |
| /* Some functions called from here depend on the @c->key_len filed */ |
| c->key_len = UBIFS_SK_LEN; |
| |
| /* |
| * First of all, we have to calculate default file-system geometry - |
| * log size, journal size, etc. |
| */ |
| if (c->leb_cnt < 0x7FFFFFFF / DEFAULT_JNL_PERCENT) |
| /* We can first multiply then divide and have no overflow */ |
| jnl_lebs = c->leb_cnt * DEFAULT_JNL_PERCENT / 100; |
| else |
| jnl_lebs = (c->leb_cnt / 100) * DEFAULT_JNL_PERCENT; |
| |
| if (jnl_lebs < UBIFS_MIN_JNL_LEBS) |
| jnl_lebs = UBIFS_MIN_JNL_LEBS; |
| if (jnl_lebs * c->leb_size > DEFAULT_MAX_JNL) |
| jnl_lebs = DEFAULT_MAX_JNL / c->leb_size; |
| |
| /* |
| * The log should be large enough to fit reference nodes for all bud |
| * LEBs. Because buds do not have to start from the beginning of LEBs |
| * (half of the LEB may contain committed data), the log should |
| * generally be larger, make it twice as large. |
| */ |
| tmp = 2 * (c->ref_node_alsz * jnl_lebs) + c->leb_size - 1; |
| log_lebs = tmp / c->leb_size; |
| /* Plus one LEB reserved for commit */ |
| log_lebs += 1; |
| if (c->leb_cnt - min_leb_cnt > 8) { |
| /* And some extra space to allow writes while committing */ |
| log_lebs += 1; |
| min_leb_cnt += 1; |
| } |
| |
| max_buds = jnl_lebs - log_lebs; |
| if (max_buds < UBIFS_MIN_BUD_LEBS) |
| max_buds = UBIFS_MIN_BUD_LEBS; |
| |
| /* |
| * Orphan nodes are stored in a separate area. One node can store a lot |
| * of orphan inode numbers, but when new orphan comes we just add a new |
| * orphan node. At some point the nodes are consolidated into one |
| * orphan node. |
| */ |
| orph_lebs = UBIFS_MIN_ORPH_LEBS; |
| if (c->leb_cnt - min_leb_cnt > 1) |
| /* |
| * For debugging purposes it is better to have at least 2 |
| * orphan LEBs, because the orphan subsystem would need to do |
| * consolidations and would be stressed more. |
| */ |
| orph_lebs += 1; |
| |
| main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - log_lebs; |
| main_lebs -= orph_lebs; |
| |
| lpt_first = UBIFS_LOG_LNUM + log_lebs; |
| c->lsave_cnt = DEFAULT_LSAVE_CNT; |
| c->max_leb_cnt = c->leb_cnt; |
| err = ubifs_create_dflt_lpt(c, &main_lebs, lpt_first, &lpt_lebs, |
| &big_lpt, hash_lpt); |
| if (err) |
| return err; |
| |
| dbg_gen("LEB Properties Tree created (LEBs %d-%d)", lpt_first, |
| lpt_first + lpt_lebs - 1); |
| |
| main_first = c->leb_cnt - main_lebs; |
| |
| sup = kzalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_KERNEL); |
| mst = kzalloc(c->mst_node_alsz, GFP_KERNEL); |
| idx_node_size = ubifs_idx_node_sz(c, 1); |
| idx = kzalloc(ALIGN(idx_node_size, c->min_io_size), GFP_KERNEL); |
| ino = kzalloc(ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size), GFP_KERNEL); |
| cs = kzalloc(ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size), GFP_KERNEL); |
| |
| if (!sup || !mst || !idx || !ino || !cs) { |
| err = -ENOMEM; |
| goto out; |
| } |
| |
| /* Create default superblock */ |
| |
| tmp64 = (long long)max_buds * c->leb_size; |
| if (big_lpt) |
| sup_flags |= UBIFS_FLG_BIGLPT; |
| sup_flags |= UBIFS_FLG_DOUBLE_HASH; |
| |
| if (ubifs_authenticated(c)) { |
| sup_flags |= UBIFS_FLG_AUTHENTICATION; |
| sup->hash_algo = cpu_to_le16(c->auth_hash_algo); |
| err = ubifs_hmac_wkm(c, sup->hmac_wkm); |
| if (err) |
| goto out; |
| } else { |
| sup->hash_algo = 0xffff; |
| } |
| |
| sup->ch.node_type = UBIFS_SB_NODE; |
| sup->key_hash = UBIFS_KEY_HASH_R5; |
| sup->flags = cpu_to_le32(sup_flags); |
| sup->min_io_size = cpu_to_le32(c->min_io_size); |
| sup->leb_size = cpu_to_le32(c->leb_size); |
| sup->leb_cnt = cpu_to_le32(c->leb_cnt); |
| sup->max_leb_cnt = cpu_to_le32(c->max_leb_cnt); |
| sup->max_bud_bytes = cpu_to_le64(tmp64); |
| sup->log_lebs = cpu_to_le32(log_lebs); |
| sup->lpt_lebs = cpu_to_le32(lpt_lebs); |
| sup->orph_lebs = cpu_to_le32(orph_lebs); |
| sup->jhead_cnt = cpu_to_le32(DEFAULT_JHEADS_CNT); |
| sup->fanout = cpu_to_le32(DEFAULT_FANOUT); |
| sup->lsave_cnt = cpu_to_le32(c->lsave_cnt); |
| sup->fmt_version = cpu_to_le32(UBIFS_FORMAT_VERSION); |
| sup->time_gran = cpu_to_le32(DEFAULT_TIME_GRAN); |
| if (c->mount_opts.override_compr) |
| sup->default_compr = cpu_to_le16(c->mount_opts.compr_type); |
| else |
| sup->default_compr = cpu_to_le16(get_default_compressor(c)); |
| |
| generate_random_uuid(sup->uuid); |
| |
| main_bytes = (long long)main_lebs * c->leb_size; |
| tmp64 = div_u64(main_bytes * DEFAULT_RP_PERCENT, 100); |
| if (tmp64 > DEFAULT_MAX_RP_SIZE) |
| tmp64 = DEFAULT_MAX_RP_SIZE; |
| sup->rp_size = cpu_to_le64(tmp64); |
| sup->ro_compat_version = cpu_to_le32(UBIFS_RO_COMPAT_VERSION); |
| |
| dbg_gen("default superblock created at LEB 0:0"); |
| |
| /* Create default master node */ |
| |
| mst->ch.node_type = UBIFS_MST_NODE; |
| mst->log_lnum = cpu_to_le32(UBIFS_LOG_LNUM); |
| mst->highest_inum = cpu_to_le64(UBIFS_FIRST_INO); |
| mst->cmt_no = 0; |
| mst->root_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB); |
| mst->root_offs = 0; |
| tmp = ubifs_idx_node_sz(c, 1); |
| mst->root_len = cpu_to_le32(tmp); |
| mst->gc_lnum = cpu_to_le32(main_first + DEFAULT_GC_LEB); |
| mst->ihead_lnum = cpu_to_le32(main_first + DEFAULT_IDX_LEB); |
| mst->ihead_offs = cpu_to_le32(ALIGN(tmp, c->min_io_size)); |
| mst->index_size = cpu_to_le64(ALIGN(tmp, 8)); |
| mst->lpt_lnum = cpu_to_le32(c->lpt_lnum); |
| mst->lpt_offs = cpu_to_le32(c->lpt_offs); |
| mst->nhead_lnum = cpu_to_le32(c->nhead_lnum); |
| mst->nhead_offs = cpu_to_le32(c->nhead_offs); |
| mst->ltab_lnum = cpu_to_le32(c->ltab_lnum); |
| mst->ltab_offs = cpu_to_le32(c->ltab_offs); |
| mst->lsave_lnum = cpu_to_le32(c->lsave_lnum); |
| mst->lsave_offs = cpu_to_le32(c->lsave_offs); |
| mst->lscan_lnum = cpu_to_le32(main_first); |
| mst->empty_lebs = cpu_to_le32(main_lebs - 2); |
| mst->idx_lebs = cpu_to_le32(1); |
| mst->leb_cnt = cpu_to_le32(c->leb_cnt); |
| ubifs_copy_hash(c, hash_lpt, mst->hash_lpt); |
| |
| /* Calculate lprops statistics */ |
| tmp64 = main_bytes; |
| tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size); |
| tmp64 -= ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size); |
| mst->total_free = cpu_to_le64(tmp64); |
| |
| tmp64 = ALIGN(ubifs_idx_node_sz(c, 1), c->min_io_size); |
| ino_waste = ALIGN(UBIFS_INO_NODE_SZ, c->min_io_size) - |
| UBIFS_INO_NODE_SZ; |
| tmp64 += ino_waste; |
| tmp64 -= ALIGN(ubifs_idx_node_sz(c, 1), 8); |
| mst->total_dirty = cpu_to_le64(tmp64); |
| |
| /* The indexing LEB does not contribute to dark space */ |
| tmp64 = ((long long)(c->main_lebs - 1) * c->dark_wm); |
| mst->total_dark = cpu_to_le64(tmp64); |
| |
| mst->total_used = cpu_to_le64(UBIFS_INO_NODE_SZ); |
| |
| dbg_gen("default master node created at LEB %d:0", UBIFS_MST_LNUM); |
| |
| /* Create the root indexing node */ |
| |
| c->key_fmt = UBIFS_SIMPLE_KEY_FMT; |
| c->key_hash = key_r5_hash; |
| |
| idx->ch.node_type = UBIFS_IDX_NODE; |
| idx->child_cnt = cpu_to_le16(1); |
| ino_key_init(c, &key, UBIFS_ROOT_INO); |
| br = ubifs_idx_branch(c, idx, 0); |
| key_write_idx(c, &key, &br->key); |
| br->lnum = cpu_to_le32(main_first + DEFAULT_DATA_LEB); |
| br->len = cpu_to_le32(UBIFS_INO_NODE_SZ); |
| |
| dbg_gen("default root indexing node created LEB %d:0", |
| main_first + DEFAULT_IDX_LEB); |
| |
| /* Create default root inode */ |
| |
| ino_key_init_flash(c, &ino->key, UBIFS_ROOT_INO); |
| ino->ch.node_type = UBIFS_INO_NODE; |
| ino->creat_sqnum = cpu_to_le64(++c->max_sqnum); |
| ino->nlink = cpu_to_le32(2); |
| |
| ktime_get_real_ts64(&ts); |
| ts = timespec64_trunc(ts, DEFAULT_TIME_GRAN); |
| tmp_le64 = cpu_to_le64(ts.tv_sec); |
| ino->atime_sec = tmp_le64; |
| ino->ctime_sec = tmp_le64; |
| ino->mtime_sec = tmp_le64; |
| tmp_le32 = cpu_to_le32(ts.tv_nsec); |
| ino->atime_nsec = tmp_le32; |
| ino->ctime_nsec = tmp_le32; |
| ino->mtime_nsec = tmp_le32; |
| ino->mode = cpu_to_le32(S_IFDIR | S_IRUGO | S_IWUSR | S_IXUGO); |
| ino->size = cpu_to_le64(UBIFS_INO_NODE_SZ); |
| |
| /* Set compression enabled by default */ |
| ino->flags = cpu_to_le32(UBIFS_COMPR_FL); |
| |
| dbg_gen("root inode created at LEB %d:0", |
| main_first + DEFAULT_DATA_LEB); |
| |
| /* |
| * The first node in the log has to be the commit start node. This is |
| * always the case during normal file-system operation. Write a fake |
| * commit start node to the log. |
| */ |
| |
| cs->ch.node_type = UBIFS_CS_NODE; |
| |
| err = ubifs_write_node_hmac(c, sup, UBIFS_SB_NODE_SZ, 0, 0, |
| offsetof(struct ubifs_sb_node, hmac)); |
| if (err) |
| goto out; |
| |
| err = ubifs_write_node(c, ino, UBIFS_INO_NODE_SZ, |
| main_first + DEFAULT_DATA_LEB, 0); |
| if (err) |
| goto out; |
| |
| ubifs_node_calc_hash(c, ino, hash); |
| ubifs_copy_hash(c, hash, ubifs_branch_hash(c, br)); |
| |
| err = ubifs_write_node(c, idx, idx_node_size, main_first + DEFAULT_IDX_LEB, 0); |
| if (err) |
| goto out; |
| |
| ubifs_node_calc_hash(c, idx, hash); |
| ubifs_copy_hash(c, hash, mst->hash_root_idx); |
| |
| err = ubifs_write_node_hmac(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM, 0, |
| offsetof(struct ubifs_mst_node, hmac)); |
| if (err) |
| goto out; |
| |
| err = ubifs_write_node_hmac(c, mst, UBIFS_MST_NODE_SZ, UBIFS_MST_LNUM + 1, |
| 0, offsetof(struct ubifs_mst_node, hmac)); |
| if (err) |
| goto out; |
| |
| err = ubifs_write_node(c, cs, UBIFS_CS_NODE_SZ, UBIFS_LOG_LNUM, 0); |
| if (err) |
| goto out; |
| |
| ubifs_msg(c, "default file-system created"); |
| |
| err = 0; |
| out: |
| kfree(sup); |
| kfree(mst); |
| kfree(idx); |
| kfree(ino); |
| kfree(cs); |
| |
| return err; |
| } |
| |
| /** |
| * validate_sb - validate superblock node. |
| * @c: UBIFS file-system description object |
| * @sup: superblock node |
| * |
| * This function validates superblock node @sup. Since most of data was read |
| * from the superblock and stored in @c, the function validates fields in @c |
| * instead. Returns zero in case of success and %-EINVAL in case of validation |
| * failure. |
| */ |
| static int validate_sb(struct ubifs_info *c, struct ubifs_sb_node *sup) |
| { |
| long long max_bytes; |
| int err = 1, min_leb_cnt; |
| |
| if (!c->key_hash) { |
| err = 2; |
| goto failed; |
| } |
| |
| if (sup->key_fmt != UBIFS_SIMPLE_KEY_FMT) { |
| err = 3; |
| goto failed; |
| } |
| |
| if (le32_to_cpu(sup->min_io_size) != c->min_io_size) { |
| ubifs_err(c, "min. I/O unit mismatch: %d in superblock, %d real", |
| le32_to_cpu(sup->min_io_size), c->min_io_size); |
| goto failed; |
| } |
| |
| if (le32_to_cpu(sup->leb_size) != c->leb_size) { |
| ubifs_err(c, "LEB size mismatch: %d in superblock, %d real", |
| le32_to_cpu(sup->leb_size), c->leb_size); |
| goto failed; |
| } |
| |
| if (c->log_lebs < UBIFS_MIN_LOG_LEBS || |
| c->lpt_lebs < UBIFS_MIN_LPT_LEBS || |
| c->orph_lebs < UBIFS_MIN_ORPH_LEBS || |
| c->main_lebs < UBIFS_MIN_MAIN_LEBS) { |
| err = 4; |
| goto failed; |
| } |
| |
| /* |
| * Calculate minimum allowed amount of main area LEBs. This is very |
| * similar to %UBIFS_MIN_LEB_CNT, but we take into account real what we |
| * have just read from the superblock. |
| */ |
| min_leb_cnt = UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs; |
| min_leb_cnt += c->lpt_lebs + c->orph_lebs + c->jhead_cnt + 6; |
| |
| if (c->leb_cnt < min_leb_cnt || c->leb_cnt > c->vi.size) { |
| ubifs_err(c, "bad LEB count: %d in superblock, %d on UBI volume, %d minimum required", |
| c->leb_cnt, c->vi.size, min_leb_cnt); |
| goto failed; |
| } |
| |
| if (c->max_leb_cnt < c->leb_cnt) { |
| ubifs_err(c, "max. LEB count %d less than LEB count %d", |
| c->max_leb_cnt, c->leb_cnt); |
| goto failed; |
| } |
| |
| if (c->main_lebs < UBIFS_MIN_MAIN_LEBS) { |
| ubifs_err(c, "too few main LEBs count %d, must be at least %d", |
| c->main_lebs, UBIFS_MIN_MAIN_LEBS); |
| goto failed; |
| } |
| |
| max_bytes = (long long)c->leb_size * UBIFS_MIN_BUD_LEBS; |
| if (c->max_bud_bytes < max_bytes) { |
| ubifs_err(c, "too small journal (%lld bytes), must be at least %lld bytes", |
| c->max_bud_bytes, max_bytes); |
| goto failed; |
| } |
| |
| max_bytes = (long long)c->leb_size * c->main_lebs; |
| if (c->max_bud_bytes > max_bytes) { |
| ubifs_err(c, "too large journal size (%lld bytes), only %lld bytes available in the main area", |
| c->max_bud_bytes, max_bytes); |
| goto failed; |
| } |
| |
| if (c->jhead_cnt < NONDATA_JHEADS_CNT + 1 || |
| c->jhead_cnt > NONDATA_JHEADS_CNT + UBIFS_MAX_JHEADS) { |
| err = 9; |
| goto failed; |
| } |
| |
| if (c->fanout < UBIFS_MIN_FANOUT || |
| ubifs_idx_node_sz(c, c->fanout) > c->leb_size) { |
| err = 10; |
| goto failed; |
| } |
| |
| if (c->lsave_cnt < 0 || (c->lsave_cnt > DEFAULT_LSAVE_CNT && |
| c->lsave_cnt > c->max_leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS - |
| c->log_lebs - c->lpt_lebs - c->orph_lebs)) { |
| err = 11; |
| goto failed; |
| } |
| |
| if (UBIFS_SB_LEBS + UBIFS_MST_LEBS + c->log_lebs + c->lpt_lebs + |
| c->orph_lebs + c->main_lebs != c->leb_cnt) { |
| err = 12; |
| goto failed; |
| } |
| |
| if (c->default_compr >= UBIFS_COMPR_TYPES_CNT) { |
| err = 13; |
| goto failed; |
| } |
| |
| if (c->rp_size < 0 || max_bytes < c->rp_size) { |
| err = 14; |
| goto failed; |
| } |
| |
| if (le32_to_cpu(sup->time_gran) > 1000000000 || |
| le32_to_cpu(sup->time_gran) < 1) { |
| err = 15; |
| goto failed; |
| } |
| |
| if (!c->double_hash && c->fmt_version >= 5) { |
| err = 16; |
| goto failed; |
| } |
| |
| if (c->encrypted && c->fmt_version < 5) { |
| err = 17; |
| goto failed; |
| } |
| |
| return 0; |
| |
| failed: |
| ubifs_err(c, "bad superblock, error %d", err); |
| ubifs_dump_node(c, sup); |
| return -EINVAL; |
| } |
| |
| /** |
| * ubifs_read_sb_node - read superblock node. |
| * @c: UBIFS file-system description object |
| * |
| * This function returns a pointer to the superblock node or a negative error |
| * code. Note, the user of this function is responsible of kfree()'ing the |
| * returned superblock buffer. |
| */ |
| static struct ubifs_sb_node *ubifs_read_sb_node(struct ubifs_info *c) |
| { |
| struct ubifs_sb_node *sup; |
| int err; |
| |
| sup = kmalloc(ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size), GFP_NOFS); |
| if (!sup) |
| return ERR_PTR(-ENOMEM); |
| |
| err = ubifs_read_node(c, sup, UBIFS_SB_NODE, UBIFS_SB_NODE_SZ, |
| UBIFS_SB_LNUM, 0); |
| if (err) { |
| kfree(sup); |
| return ERR_PTR(err); |
| } |
| |
| return sup; |
| } |
| |
| static int authenticate_sb_node(struct ubifs_info *c, |
| const struct ubifs_sb_node *sup) |
| { |
| unsigned int sup_flags = le32_to_cpu(sup->flags); |
| u8 hmac_wkm[UBIFS_HMAC_ARR_SZ]; |
| int authenticated = !!(sup_flags & UBIFS_FLG_AUTHENTICATION); |
| int hash_algo; |
| int err; |
| |
| if (c->authenticated && !authenticated) { |
| ubifs_err(c, "authenticated FS forced, but found FS without authentication"); |
| return -EINVAL; |
| } |
| |
| if (!c->authenticated && authenticated) { |
| ubifs_err(c, "authenticated FS found, but no key given"); |
| return -EINVAL; |
| } |
| |
| ubifs_msg(c, "Mounting in %sauthenticated mode", |
| c->authenticated ? "" : "un"); |
| |
| if (!c->authenticated) |
| return 0; |
| |
| if (!IS_ENABLED(CONFIG_UBIFS_FS_AUTHENTICATION)) |
| return -EOPNOTSUPP; |
| |
| hash_algo = le16_to_cpu(sup->hash_algo); |
| if (hash_algo >= HASH_ALGO__LAST) { |
| ubifs_err(c, "superblock uses unknown hash algo %d", |
| hash_algo); |
| return -EINVAL; |
| } |
| |
| if (strcmp(hash_algo_name[hash_algo], c->auth_hash_name)) { |
| ubifs_err(c, "This filesystem uses %s for hashing," |
| " but %s is specified", hash_algo_name[hash_algo], |
| c->auth_hash_name); |
| return -EINVAL; |
| } |
| |
| /* |
| * The super block node can either be authenticated by a HMAC or |
| * by a signature in a ubifs_sig_node directly following the |
| * super block node to support offline image creation. |
| */ |
| if (ubifs_hmac_zero(c, sup->hmac)) { |
| err = ubifs_sb_verify_signature(c, sup); |
| } else { |
| err = ubifs_hmac_wkm(c, hmac_wkm); |
| if (err) |
| return err; |
| if (ubifs_check_hmac(c, hmac_wkm, sup->hmac_wkm)) { |
| ubifs_err(c, "provided key does not fit"); |
| return -ENOKEY; |
| } |
| err = ubifs_node_verify_hmac(c, sup, sizeof(*sup), |
| offsetof(struct ubifs_sb_node, |
| hmac)); |
| } |
| |
| if (err) |
| ubifs_err(c, "Failed to authenticate superblock: %d", err); |
| |
| return err; |
| } |
| |
| /** |
| * ubifs_write_sb_node - write superblock node. |
| * @c: UBIFS file-system description object |
| * @sup: superblock node read with 'ubifs_read_sb_node()' |
| * |
| * This function returns %0 on success and a negative error code on failure. |
| */ |
| int ubifs_write_sb_node(struct ubifs_info *c, struct ubifs_sb_node *sup) |
| { |
| int len = ALIGN(UBIFS_SB_NODE_SZ, c->min_io_size); |
| int err; |
| |
| err = ubifs_prepare_node_hmac(c, sup, UBIFS_SB_NODE_SZ, |
| offsetof(struct ubifs_sb_node, hmac), 1); |
| if (err) |
| return err; |
| |
| return ubifs_leb_change(c, UBIFS_SB_LNUM, sup, len); |
| } |
| |
| /** |
| * ubifs_read_superblock - read superblock. |
| * @c: UBIFS file-system description object |
| * |
| * This function finds, reads and checks the superblock. If an empty UBI volume |
| * is being mounted, this function creates default superblock. Returns zero in |
| * case of success, and a negative error code in case of failure. |
| */ |
| int ubifs_read_superblock(struct ubifs_info *c) |
| { |
| int err, sup_flags; |
| struct ubifs_sb_node *sup; |
| |
| if (c->empty) { |
| err = create_default_filesystem(c); |
| if (err) |
| return err; |
| } |
| |
| sup = ubifs_read_sb_node(c); |
| if (IS_ERR(sup)) |
| return PTR_ERR(sup); |
| |
| c->sup_node = sup; |
| |
| c->fmt_version = le32_to_cpu(sup->fmt_version); |
| c->ro_compat_version = le32_to_cpu(sup->ro_compat_version); |
| |
| /* |
| * The software supports all previous versions but not future versions, |
| * due to the unavailability of time-travelling equipment. |
| */ |
| if (c->fmt_version > UBIFS_FORMAT_VERSION) { |
| ubifs_assert(c, !c->ro_media || c->ro_mount); |
| if (!c->ro_mount || |
| c->ro_compat_version > UBIFS_RO_COMPAT_VERSION) { |
| ubifs_err(c, "on-flash format version is w%d/r%d, but software only supports up to version w%d/r%d", |
| c->fmt_version, c->ro_compat_version, |
| UBIFS_FORMAT_VERSION, |
| UBIFS_RO_COMPAT_VERSION); |
| if (c->ro_compat_version <= UBIFS_RO_COMPAT_VERSION) { |
| ubifs_msg(c, "only R/O mounting is possible"); |
| err = -EROFS; |
| } else |
| err = -EINVAL; |
| goto out; |
| } |
| |
| /* |
| * The FS is mounted R/O, and the media format is |
| * R/O-compatible with the UBIFS implementation, so we can |
| * mount. |
| */ |
| c->rw_incompat = 1; |
| } |
| |
| if (c->fmt_version < 3) { |
| ubifs_err(c, "on-flash format version %d is not supported", |
| c->fmt_version); |
| err = -EINVAL; |
| goto out; |
| } |
| |
| switch (sup->key_hash) { |
| case UBIFS_KEY_HASH_R5: |
| c->key_hash = key_r5_hash; |
| c->key_hash_type = UBIFS_KEY_HASH_R5; |
| break; |
| |
| case UBIFS_KEY_HASH_TEST: |
| c->key_hash = key_test_hash; |
| c->key_hash_type = UBIFS_KEY_HASH_TEST; |
| break; |
| } |
| |
| c->key_fmt = sup->key_fmt; |
| |
| switch (c->key_fmt) { |
| case UBIFS_SIMPLE_KEY_FMT: |
| c->key_len = UBIFS_SK_LEN; |
| break; |
| default: |
| ubifs_err(c, "unsupported key format"); |
| err = -EINVAL; |
| goto out; |
| } |
| |
| c->leb_cnt = le32_to_cpu(sup->leb_cnt); |
| c->max_leb_cnt = le32_to_cpu(sup->max_leb_cnt); |
| c->max_bud_bytes = le64_to_cpu(sup->max_bud_bytes); |
| c->log_lebs = le32_to_cpu(sup->log_lebs); |
| c->lpt_lebs = le32_to_cpu(sup->lpt_lebs); |
| c->orph_lebs = le32_to_cpu(sup->orph_lebs); |
| c->jhead_cnt = le32_to_cpu(sup->jhead_cnt) + NONDATA_JHEADS_CNT; |
| c->fanout = le32_to_cpu(sup->fanout); |
| c->lsave_cnt = le32_to_cpu(sup->lsave_cnt); |
| c->rp_size = le64_to_cpu(sup->rp_size); |
| c->rp_uid = make_kuid(&init_user_ns, le32_to_cpu(sup->rp_uid)); |
| c->rp_gid = make_kgid(&init_user_ns, le32_to_cpu(sup->rp_gid)); |
| sup_flags = le32_to_cpu(sup->flags); |
| if (!c->mount_opts.override_compr) |
| c->default_compr = le16_to_cpu(sup->default_compr); |
| |
| c->vfs_sb->s_time_gran = le32_to_cpu(sup->time_gran); |
| memcpy(&c->uuid, &sup->uuid, 16); |
| c->big_lpt = !!(sup_flags & UBIFS_FLG_BIGLPT); |
| c->space_fixup = !!(sup_flags & UBIFS_FLG_SPACE_FIXUP); |
| c->double_hash = !!(sup_flags & UBIFS_FLG_DOUBLE_HASH); |
| c->encrypted = !!(sup_flags & UBIFS_FLG_ENCRYPTION); |
| |
| err = authenticate_sb_node(c, sup); |
| if (err) |
| goto out; |
| |
| if ((sup_flags & ~UBIFS_FLG_MASK) != 0) { |
| ubifs_err(c, "Unknown feature flags found: %#x", |
| sup_flags & ~UBIFS_FLG_MASK); |
| err = -EINVAL; |
| goto out; |
| } |
| |
| if (!IS_ENABLED(CONFIG_FS_ENCRYPTION) && c->encrypted) { |
| ubifs_err(c, "file system contains encrypted files but UBIFS" |
| " was built without crypto support."); |
| err = -EINVAL; |
| goto out; |
| } |
| |
| /* Automatically increase file system size to the maximum size */ |
| if (c->leb_cnt < c->vi.size && c->leb_cnt < c->max_leb_cnt) { |
| int old_leb_cnt = c->leb_cnt; |
| |
| c->leb_cnt = min_t(int, c->max_leb_cnt, c->vi.size); |
| sup->leb_cnt = cpu_to_le32(c->leb_cnt); |
| |
| c->superblock_need_write = 1; |
| |
| dbg_mnt("Auto resizing from %d LEBs to %d LEBs", |
| old_leb_cnt, c->leb_cnt); |
| } |
| |
| c->log_bytes = (long long)c->log_lebs * c->leb_size; |
| c->log_last = UBIFS_LOG_LNUM + c->log_lebs - 1; |
| c->lpt_first = UBIFS_LOG_LNUM + c->log_lebs; |
| c->lpt_last = c->lpt_first + c->lpt_lebs - 1; |
| c->orph_first = c->lpt_last + 1; |
| c->orph_last = c->orph_first + c->orph_lebs - 1; |
| c->main_lebs = c->leb_cnt - UBIFS_SB_LEBS - UBIFS_MST_LEBS; |
| c->main_lebs -= c->log_lebs + c->lpt_lebs + c->orph_lebs; |
| c->main_first = c->leb_cnt - c->main_lebs; |
| |
| err = validate_sb(c, sup); |
| out: |
| return err; |
| } |
| |
| /** |
| * fixup_leb - fixup/unmap an LEB containing free space. |
| * @c: UBIFS file-system description object |
| * @lnum: the LEB number to fix up |
| * @len: number of used bytes in LEB (starting at offset 0) |
| * |
| * This function reads the contents of the given LEB number @lnum, then fixes |
| * it up, so that empty min. I/O units in the end of LEB are actually erased on |
| * flash (rather than being just all-0xff real data). If the LEB is completely |
| * empty, it is simply unmapped. |
| */ |
| static int fixup_leb(struct ubifs_info *c, int lnum, int len) |
| { |
| int err; |
| |
| ubifs_assert(c, len >= 0); |
| ubifs_assert(c, len % c->min_io_size == 0); |
| ubifs_assert(c, len < c->leb_size); |
| |
| if (len == 0) { |
| dbg_mnt("unmap empty LEB %d", lnum); |
| return ubifs_leb_unmap(c, lnum); |
| } |
| |
| dbg_mnt("fixup LEB %d, data len %d", lnum, len); |
| err = ubifs_leb_read(c, lnum, c->sbuf, 0, len, 1); |
| if (err) |
| return err; |
| |
| return ubifs_leb_change(c, lnum, c->sbuf, len); |
| } |
| |
| /** |
| * fixup_free_space - find & remap all LEBs containing free space. |
| * @c: UBIFS file-system description object |
| * |
| * This function walks through all LEBs in the filesystem and fiexes up those |
| * containing free/empty space. |
| */ |
| static int fixup_free_space(struct ubifs_info *c) |
| { |
| int lnum, err = 0; |
| struct ubifs_lprops *lprops; |
| |
| ubifs_get_lprops(c); |
| |
| /* Fixup LEBs in the master area */ |
| for (lnum = UBIFS_MST_LNUM; lnum < UBIFS_LOG_LNUM; lnum++) { |
| err = fixup_leb(c, lnum, c->mst_offs + c->mst_node_alsz); |
| if (err) |
| goto out; |
| } |
| |
| /* Unmap unused log LEBs */ |
| lnum = ubifs_next_log_lnum(c, c->lhead_lnum); |
| while (lnum != c->ltail_lnum) { |
| err = fixup_leb(c, lnum, 0); |
| if (err) |
| goto out; |
| lnum = ubifs_next_log_lnum(c, lnum); |
| } |
| |
| /* |
| * Fixup the log head which contains the only a CS node at the |
| * beginning. |
| */ |
| err = fixup_leb(c, c->lhead_lnum, |
| ALIGN(UBIFS_CS_NODE_SZ, c->min_io_size)); |
| if (err) |
| goto out; |
| |
| /* Fixup LEBs in the LPT area */ |
| for (lnum = c->lpt_first; lnum <= c->lpt_last; lnum++) { |
| int free = c->ltab[lnum - c->lpt_first].free; |
| |
| if (free > 0) { |
| err = fixup_leb(c, lnum, c->leb_size - free); |
| if (err) |
| goto out; |
| } |
| } |
| |
| /* Unmap LEBs in the orphans area */ |
| for (lnum = c->orph_first; lnum <= c->orph_last; lnum++) { |
| err = fixup_leb(c, lnum, 0); |
| if (err) |
| goto out; |
| } |
| |
| /* Fixup LEBs in the main area */ |
| for (lnum = c->main_first; lnum < c->leb_cnt; lnum++) { |
| lprops = ubifs_lpt_lookup(c, lnum); |
| if (IS_ERR(lprops)) { |
| err = PTR_ERR(lprops); |
| goto out; |
| } |
| |
| if (lprops->free > 0) { |
| err = fixup_leb(c, lnum, c->leb_size - lprops->free); |
| if (err) |
| goto out; |
| } |
| } |
| |
| out: |
| ubifs_release_lprops(c); |
| return err; |
| } |
| |
| /** |
| * ubifs_fixup_free_space - find & fix all LEBs with free space. |
| * @c: UBIFS file-system description object |
| * |
| * This function fixes up LEBs containing free space on first mount, if the |
| * appropriate flag was set when the FS was created. Each LEB with one or more |
| * empty min. I/O unit (i.e. free-space-count > 0) is re-written, to make sure |
| * the free space is actually erased. E.g., this is necessary for some NAND |
| * chips, since the free space may have been programmed like real "0xff" data |
| * (generating a non-0xff ECC), causing future writes to the not-really-erased |
| * NAND pages to behave badly. After the space is fixed up, the superblock flag |
| * is cleared, so that this is skipped for all future mounts. |
| */ |
| int ubifs_fixup_free_space(struct ubifs_info *c) |
| { |
| int err; |
| struct ubifs_sb_node *sup = c->sup_node; |
| |
| ubifs_assert(c, c->space_fixup); |
| ubifs_assert(c, !c->ro_mount); |
| |
| ubifs_msg(c, "start fixing up free space"); |
| |
| err = fixup_free_space(c); |
| if (err) |
| return err; |
| |
| /* Free-space fixup is no longer required */ |
| c->space_fixup = 0; |
| sup->flags &= cpu_to_le32(~UBIFS_FLG_SPACE_FIXUP); |
| |
| c->superblock_need_write = 1; |
| |
| ubifs_msg(c, "free space fixup complete"); |
| return err; |
| } |
| |
| int ubifs_enable_encryption(struct ubifs_info *c) |
| { |
| int err; |
| struct ubifs_sb_node *sup = c->sup_node; |
| |
| if (!IS_ENABLED(CONFIG_FS_ENCRYPTION)) |
| return -EOPNOTSUPP; |
| |
| if (c->encrypted) |
| return 0; |
| |
| if (c->ro_mount || c->ro_media) |
| return -EROFS; |
| |
| if (c->fmt_version < 5) { |
| ubifs_err(c, "on-flash format version 5 is needed for encryption"); |
| return -EINVAL; |
| } |
| |
| sup->flags |= cpu_to_le32(UBIFS_FLG_ENCRYPTION); |
| |
| err = ubifs_write_sb_node(c, sup); |
| if (!err) |
| c->encrypted = 1; |
| |
| return err; |
| } |