static struct dentry *squashfs_export_iget(struct super_block *sb, unsigned int ino_num) { long long ino; struct dentry *dentry = ERR_PTR(-ENOENT); TRACE("Entered squashfs_export_iget\n"); ino = squashfs_inode_lookup(sb, ino_num); if (ino >= 0) dentry = d_obtain_alias(squashfs_iget(sb, ino, ino_num)); return dentry; }
static struct dentry *squashfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { const unsigned char *name = dentry->d_name.name; int len = dentry->d_name.len; struct inode *inode = NULL; struct squashfs_sb_info *msblk = dir->i_sb->s_fs_info; struct squashfs_dir_header dirh; struct squashfs_dir_entry *dire; u64 block = squashfs_i(dir)->start + msblk->directory_table; int offset = squashfs_i(dir)->offset; int err, length; unsigned int dir_count, size; TRACE("Entered squashfs_lookup [%llx:%x]\n", block, offset); dire = kmalloc(sizeof(*dire) + SQUASHFS_NAME_LEN + 1, GFP_KERNEL); if (dire == NULL) { ERROR("Failed to allocate squashfs_dir_entry\n"); return ERR_PTR(-ENOMEM); } if (len > SQUASHFS_NAME_LEN) { err = -ENAMETOOLONG; goto failed; } length = get_dir_index_using_name(dir->i_sb, &block, &offset, squashfs_i(dir)->dir_idx_start, squashfs_i(dir)->dir_idx_offset, squashfs_i(dir)->dir_idx_cnt, name, len); while (length < i_size_read(dir)) { /* * Read directory header. */ err = squashfs_read_metadata(dir->i_sb, &dirh, &block, &offset, sizeof(dirh)); if (err < 0) goto read_failure; length += sizeof(dirh); dir_count = le32_to_cpu(dirh.count) + 1; if (dir_count > SQUASHFS_DIR_COUNT) goto data_error; while (dir_count--) { /* * Read directory entry. */ err = squashfs_read_metadata(dir->i_sb, dire, &block, &offset, sizeof(*dire)); if (err < 0) goto read_failure; size = le16_to_cpu(dire->size) + 1; /* size should never be larger than SQUASHFS_NAME_LEN */ if (size > SQUASHFS_NAME_LEN) goto data_error; err = squashfs_read_metadata(dir->i_sb, dire->name, &block, &offset, size); if (err < 0) goto read_failure; length += sizeof(*dire) + size; if (name[0] < dire->name[0]) goto exit_lookup; if (len == size && !strncmp(name, dire->name, len)) { unsigned int blk, off, ino_num; long long ino; blk = le32_to_cpu(dirh.start_block); off = le16_to_cpu(dire->offset); ino_num = le32_to_cpu(dirh.inode_number) + (short) le16_to_cpu(dire->inode_number); ino = SQUASHFS_MKINODE(blk, off); TRACE("calling squashfs_iget for directory " "entry %s, inode %x:%x, %d\n", name, blk, off, ino_num); inode = squashfs_iget(dir->i_sb, ino, ino_num); goto exit_lookup; } } } exit_lookup: kfree(dire); return d_splice_alias(inode, dentry); data_error: err = -EIO; read_failure: ERROR("Unable to read directory block [%llx:%x]\n", squashfs_i(dir)->start + msblk->directory_table, squashfs_i(dir)->offset); failed: kfree(dire); return ERR_PTR(err); }
static int squashfs_fill_super(struct super_block *sb, void *data, int silent) { struct squashfs_sb_info *msblk; struct fs_device_d *fsdev = (struct fs_device_d *)data; struct squashfs_super_block *sblk = NULL; struct inode *root; long long root_inode; unsigned short flags; unsigned int fragments; u64 lookup_table_start, next_table; int err; TRACE("Entered squashfs_fill_superblock\n"); sb->s_fs_info = kzalloc(sizeof(*msblk), GFP_KERNEL); if (sb->s_fs_info == NULL) { ERROR("Failed to allocate squashfs_sb_info\n"); return -ENOMEM; } msblk = sb->s_fs_info; msblk->cdev = fsdev->cdev; msblk->dev = &fsdev->dev; msblk->devblksize = 1024; msblk->devblksize_log2 = ffz(~msblk->devblksize); mutex_init(&msblk->meta_index_mutex); /* * msblk->bytes_used is checked in squashfs_read_table to ensure reads * are not beyond filesystem end. But as we're using * squashfs_read_table here to read the superblock (including the value * of bytes_used) we need to set it to an initial sensible dummy value */ msblk->bytes_used = sizeof(*sblk); sblk = squashfs_read_table(sb, SQUASHFS_START, sizeof(*sblk)); if (IS_ERR(sblk)) { ERROR("unable to read squashfs_super_block\n"); err = PTR_ERR(sblk); sblk = NULL; goto failed_mount; } err = -EINVAL; /* Check it is a SQUASHFS superblock */ sb->s_magic = le32_to_cpu(sblk->s_magic); if (sb->s_magic != SQUASHFS_MAGIC) { if (!silent) ERROR("Can't find a SQUASHFS superblock on %pg\n", sb->s_bdev); goto failed_mount; } /* Check the MAJOR & MINOR versions and lookup compression type */ msblk->decompressor = supported_squashfs_filesystem( le16_to_cpu(sblk->s_major), le16_to_cpu(sblk->s_minor), le16_to_cpu(sblk->compression)); if (msblk->decompressor == NULL) goto failed_mount; /* Check the filesystem does not extend beyond the end of the block device */ msblk->bytes_used = le64_to_cpu(sblk->bytes_used); if (msblk->bytes_used < 0 || msblk->bytes_used > msblk->cdev->size) goto failed_mount; /* Check block size for sanity */ msblk->block_size = le32_to_cpu(sblk->block_size); if (msblk->block_size > SQUASHFS_FILE_MAX_SIZE) goto failed_mount; /* * Check the system page size is not larger than the filesystem * block size (by default 128K). This is currently not supported. */ if (PAGE_CACHE_SIZE > msblk->block_size) { ERROR("Page size > filesystem block size (%d). This is " "currently not supported!\n", msblk->block_size); goto failed_mount; } /* Check block log for sanity */ msblk->block_log = le16_to_cpu(sblk->block_log); if (msblk->block_log > SQUASHFS_FILE_MAX_LOG) goto failed_mount; /* Check that block_size and block_log match */ if (msblk->block_size != (1 << msblk->block_log)) goto failed_mount; /* Check the root inode for sanity */ root_inode = le64_to_cpu(sblk->root_inode); if (SQUASHFS_INODE_OFFSET(root_inode) > SQUASHFS_METADATA_SIZE) goto failed_mount; msblk->inode_table = le64_to_cpu(sblk->inode_table_start); msblk->directory_table = le64_to_cpu(sblk->directory_table_start); msblk->inodes = le32_to_cpu(sblk->inodes); flags = le16_to_cpu(sblk->flags); TRACE("Found valid superblock on %pg\n", sb->s_bdev); TRACE("Inodes are %scompressed\n", SQUASHFS_UNCOMPRESSED_INODES(flags) ? "un" : ""); TRACE("Data is %scompressed\n", SQUASHFS_UNCOMPRESSED_DATA(flags) ? "un" : ""); TRACE("Filesystem size %lld bytes\n", msblk->bytes_used); TRACE("Block size %d\n", msblk->block_size); TRACE("Number of inodes %d\n", msblk->inodes); TRACE("Number of fragments %d\n", le32_to_cpu(sblk->fragments)); TRACE("Number of ids %d\n", le16_to_cpu(sblk->no_ids)); TRACE("sblk->inode_table_start %llx\n", msblk->inode_table); TRACE("sblk->directory_table_start %llx\n", msblk->directory_table); TRACE("sblk->fragment_table_start %llx\n", (u64) le64_to_cpu(sblk->fragment_table_start)); TRACE("sblk->id_table_start %llx\n", (u64) le64_to_cpu(sblk->id_table_start)); sb->s_maxbytes = MAX_LFS_FILESIZE; sb->s_flags |= MS_RDONLY; err = -ENOMEM; msblk->block_cache = squashfs_cache_init("metadata", SQUASHFS_CACHED_BLKS, SQUASHFS_METADATA_SIZE); if (msblk->block_cache == NULL) goto failed_mount; /* Allocate read_page block */ msblk->read_page = squashfs_cache_init("data", squashfs_max_decompressors(), msblk->block_size); if (msblk->read_page == NULL) { ERROR("Failed to allocate read_page block\n"); goto failed_mount; } msblk->stream = squashfs_decompressor_setup(sb, flags); if (IS_ERR(msblk->stream)) { err = PTR_ERR(msblk->stream); msblk->stream = NULL; goto failed_mount; } next_table = msblk->bytes_used; /* Allocate and read id index table */ msblk->id_table = squashfs_read_id_index_table(sb, le64_to_cpu(sblk->id_table_start), next_table, le16_to_cpu(sblk->no_ids)); if (IS_ERR(msblk->id_table)) { ERROR("unable to read id index table\n"); err = PTR_ERR(msblk->id_table); msblk->id_table = NULL; goto failed_mount; } next_table = le64_to_cpu(msblk->id_table[0]); /* Handle inode lookup table */ lookup_table_start = le64_to_cpu(sblk->lookup_table_start); if (lookup_table_start == SQUASHFS_INVALID_BLK) goto handle_fragments; handle_fragments: fragments = le32_to_cpu(sblk->fragments); if (fragments == 0) goto check_directory_table; msblk->fragment_cache = squashfs_cache_init("fragment", SQUASHFS_CACHED_FRAGMENTS, msblk->block_size); if (msblk->fragment_cache == NULL) { err = -ENOMEM; goto failed_mount; } /* Allocate and read fragment index table */ msblk->fragment_index = squashfs_read_fragment_index_table(sb, le64_to_cpu(sblk->fragment_table_start), next_table, fragments); if (IS_ERR(msblk->fragment_index)) { ERROR("unable to read fragment index table\n"); err = PTR_ERR(msblk->fragment_index); msblk->fragment_index = NULL; goto failed_mount; } next_table = le64_to_cpu(msblk->fragment_index[0]); check_directory_table: /* Sanity check directory_table */ if (msblk->directory_table > next_table) { err = -EINVAL; goto failed_mount; } /* Sanity check inode_table */ if (msblk->inode_table >= msblk->directory_table) { err = -EINVAL; goto failed_mount; } /* allocate root */ root = squashfs_iget(sb, root_inode, 1); if (!root) { err = -ENOMEM; goto failed_mount; } sb->s_root = d_make_root(root); if (sb->s_root == NULL) { ERROR("Root inode create failed\n"); err = -ENOMEM; goto failed_mount; } kfree(sblk); return 0; failed_mount: squashfs_cache_delete(msblk->block_cache); squashfs_cache_delete(msblk->fragment_cache); squashfs_cache_delete(msblk->read_page); squashfs_decompressor_destroy(msblk); kfree(msblk->inode_lookup_table); kfree(msblk->fragment_index); kfree(msblk->id_table); kfree(msblk->xattr_id_table); kfree(sb->s_fs_info); sb->s_fs_info = NULL; kfree(sblk); return err; }
static struct dentry *squashfs_lookup_2(struct inode *i, struct dentry *dentry, struct nameidata *nd) { const unsigned char *name = dentry->d_name.name; int len = dentry->d_name.len; struct inode *inode = NULL; struct squashfs_sb_info *msblk = i->i_sb->s_fs_info; struct squashfs_super_block *sblk = &msblk->sblk; long long next_block = SQUASHFS_I(i)->start_block + sblk->directory_table_start; int next_offset = SQUASHFS_I(i)->offset, length = 0, dir_count; struct squashfs_dir_header_2 dirh; struct squashfs_dir_entry_2 *dire; int sorted = sblk->s_major == 2 && sblk->s_minor >= 1; TRACE("Entered squashfs_lookup_2 [%llx:%x]\n", next_block, next_offset); if (!(dire = kmalloc(sizeof(struct squashfs_dir_entry) + SQUASHFS_NAME_LEN + 1, GFP_KERNEL))) { ERROR("Failed to allocate squashfs_dir_entry\n"); goto exit_loop; } if (len > SQUASHFS_NAME_LEN) goto exit_loop; length = get_dir_index_using_name(i->i_sb, &next_block, &next_offset, SQUASHFS_I(i)->u.s2.directory_index_start, SQUASHFS_I(i)->u.s2.directory_index_offset, SQUASHFS_I(i)->u.s2.directory_index_count, name, len); while (length < i_size_read(i)) { /* read directory header */ if (msblk->swap) { struct squashfs_dir_header_2 sdirh; if (!squashfs_get_cached_block(i->i_sb, (char *) &sdirh, next_block, next_offset, sizeof(sdirh), &next_block, &next_offset)) goto failed_read; length += sizeof(sdirh); SQUASHFS_SWAP_DIR_HEADER_2(&dirh, &sdirh); } else { if (!squashfs_get_cached_block(i->i_sb, (char *) &dirh, next_block, next_offset, sizeof(dirh), &next_block, &next_offset)) goto failed_read; length += sizeof(dirh); } dir_count = dirh.count + 1; while (dir_count--) { if (msblk->swap) { struct squashfs_dir_entry_2 sdire; if (!squashfs_get_cached_block(i->i_sb, (char *) &sdire, next_block,next_offset, sizeof(sdire), &next_block, &next_offset)) goto failed_read; length += sizeof(sdire); SQUASHFS_SWAP_DIR_ENTRY_2(dire, &sdire); } else { if (!squashfs_get_cached_block(i->i_sb, (char *) dire, next_block,next_offset, sizeof(*dire), &next_block, &next_offset)) goto failed_read; length += sizeof(*dire); } if (!squashfs_get_cached_block(i->i_sb, dire->name, next_block, next_offset, dire->size + 1, &next_block, &next_offset)) goto failed_read; length += dire->size + 1; if (sorted && name[0] < dire->name[0]) goto exit_loop; if ((len == dire->size + 1) && !strncmp(name, dire->name, len)) { squashfs_inode_t ino = SQUASHFS_MKINODE(dirh.start_block, dire->offset); unsigned int inode_number = SQUASHFS_MK_VFS_INODE(dirh.start_block, dire->offset); TRACE("calling squashfs_iget for directory " "entry %s, inode %x:%x, %lld\n", name, dirh.start_block, dire->offset, ino); inode = squashfs_iget(i->i_sb, ino, inode_number); goto exit_loop; } } } exit_loop: kfree(dire); d_add(dentry, inode); return ERR_PTR(0); failed_read: ERROR("Unable to read directory block [%llx:%x]\n", next_block, next_offset); goto exit_loop; }