int read_super(int fd, squashfs_super_block *sBlk, int *be, char *source) { read_bytes(fd, SQUASHFS_START, sizeof(squashfs_super_block), (char *) sBlk); /* Check it is a SQUASHFS superblock */ swap = 0; if(sBlk->s_magic != SQUASHFS_MAGIC) { if(sBlk->s_magic == SQUASHFS_MAGIC_SWAP) { squashfs_super_block sblk; ERROR("Reading a different endian SQUASHFS filesystem on %s - ignoring -le/-be options\n", source); SQUASHFS_SWAP_SUPER_BLOCK(&sblk, sBlk); memcpy(sBlk, &sblk, sizeof(squashfs_super_block)); swap = 1; } else { ERROR("Can't find a SQUASHFS superblock on %s\n", source); goto failed_mount; } } /* Check the MAJOR & MINOR versions */ if(sBlk->s_major != SQUASHFS_MAJOR || sBlk->s_minor > SQUASHFS_MINOR) { if(sBlk->s_major == 1) ERROR("Filesystem on %s is a SQUASHFS 1.x filesystem. Appending\nto SQUASHFS 1.x filesystems is not supported. Please convert it to a SQUASHFS 2.1 filesystem...n", source); else ERROR("Major/Minor mismatch, filesystem on %s is (%d:%d), I support (%d: <= %d)\n", source, sBlk->s_major, sBlk->s_minor, SQUASHFS_MAJOR, SQUASHFS_MINOR); goto failed_mount; } #if __BYTE_ORDER == __BIG_ENDIAN *be = !swap; #else *be = swap; #endif printf("Found a valid SQUASHFS superblock on %s.\n", source); printf("\tInodes are %scompressed\n", SQUASHFS_UNCOMPRESSED_INODES(sBlk->flags) ? "un" : ""); printf("\tData is %scompressed\n", SQUASHFS_UNCOMPRESSED_DATA(sBlk->flags) ? "un" : ""); printf("\tFragments are %scompressed\n", SQUASHFS_UNCOMPRESSED_FRAGMENTS(sBlk->flags) ? "un" : ""); printf("\tCheck data is %s present in the filesystem\n", SQUASHFS_CHECK_DATA(sBlk->flags) ? "" : "not"); printf("\tFragments are %s present in the filesystem\n", SQUASHFS_NO_FRAGMENTS(sBlk->flags) ? "not" : ""); printf("\tAlways_use_fragments option is %s specified\n", SQUASHFS_ALWAYS_FRAGMENTS(sBlk->flags) ? "" : "not"); printf("\tDuplicates are %s removed\n", SQUASHFS_DUPLICATES(sBlk->flags) ? "" : "not"); printf("\tFilesystem size %d bytes\n", sBlk->bytes_used); printf("\tBlock size %d\n", sBlk->block_size); printf("\tNumber of fragments %d\n", sBlk->fragments); printf("\tNumber of inodes %d\n", sBlk->inodes); printf("\tNumber of uids %d\n", sBlk->no_uids); printf("\tNumber of gids %d\n", sBlk->no_guids); TRACE("sBlk->inode_table_start %x\n", sBlk->inode_table_start); TRACE("sBlk->directory_table_start %x\n", sBlk->directory_table_start); TRACE("sBlk->uid_start %x\n", sBlk->uid_start); TRACE("sBlk->fragment_table_start %x\n", sBlk->fragment_table_start); printf("\n"); return TRUE; failed_mount: return FALSE; }
struct compressor *read_super(int fd, struct squashfs_super_block *sBlk, char *source) { int res, bytes = 0; char buffer[SQUASHFS_METADATA_SIZE] __attribute__ ((aligned)); res = read_fs_bytes(fd, SQUASHFS_START, sizeof(struct squashfs_super_block), sBlk); if(res == 0) { ERROR("Can't find a SQUASHFS superblock on %s\n", source); ERROR("Wrong filesystem or filesystem is corrupted!\n"); goto failed_mount; } SQUASHFS_INSWAP_SUPER_BLOCK(sBlk); if(sBlk->s_magic != SQUASHFS_MAGIC) { if(sBlk->s_magic == SQUASHFS_MAGIC_SWAP) ERROR("Pre 4.0 big-endian filesystem on %s, appending" " to this is unsupported\n", source); else { ERROR("Can't find a SQUASHFS superblock on %s\n", source); ERROR("Wrong filesystem or filesystem is corrupted!\n"); } goto failed_mount; } /* Check the MAJOR & MINOR versions */ if(sBlk->s_major != SQUASHFS_MAJOR || sBlk->s_minor > SQUASHFS_MINOR) { if(sBlk->s_major < 4) ERROR("Filesystem on %s is a SQUASHFS %d.%d filesystem." " Appending\nto SQUASHFS %d.%d filesystems is " "not supported. Please convert it to a " "SQUASHFS 4 filesystem\n", source, sBlk->s_major, sBlk->s_minor, sBlk->s_major, sBlk->s_minor); else ERROR("Filesystem on %s is %d.%d, which is a later " "filesystem version than I support\n", source, sBlk->s_major, sBlk->s_minor); goto failed_mount; } /* Check the compression type */ comp = lookup_compressor_id(sBlk->compression); if(!comp->supported) { ERROR("Filesystem on %s uses %s compression, this is " "unsupported by this version\n", source, comp->name); ERROR("Compressors available:\n"); display_compressors("", ""); goto failed_mount; } /* * Read extended superblock information from disk. * * Read compressor specific options from disk if present, and pass * to compressor to set compressor options. * * Note, if there's no compressor options present, the compressor * is still called to set the default options (the defaults may have * been changed by the user specifying options on the command * line which need to be over-ridden). * * Compressor_extract_options is also used to ensure that * we know how decompress a filesystem compressed with these * compression options. */ if(SQUASHFS_COMP_OPTS(sBlk->flags)) { bytes = read_block(fd, sizeof(*sBlk), NULL, 0, buffer); if(bytes == 0) { ERROR("Failed to read compressor options from append " "filesystem\n"); ERROR("Filesystem corrupted?\n"); goto failed_mount; } } res = compressor_extract_options(comp, sBlk->block_size, buffer, bytes); if(res == -1) { ERROR("Compressor failed to set compressor options\n"); goto failed_mount; } printf("Found a valid %sSQUASHFS superblock on %s.\n", SQUASHFS_EXPORTABLE(sBlk->flags) ? "exportable " : "", source); printf("\tCompression used %s\n", comp->name); printf("\tInodes are %scompressed\n", SQUASHFS_UNCOMPRESSED_INODES(sBlk->flags) ? "un" : ""); printf("\tData is %scompressed\n", SQUASHFS_UNCOMPRESSED_DATA(sBlk->flags) ? "un" : ""); printf("\tFragments are %scompressed\n", SQUASHFS_UNCOMPRESSED_FRAGMENTS(sBlk->flags) ? "un" : ""); printf("\tXattrs are %scompressed\n", SQUASHFS_UNCOMPRESSED_XATTRS(sBlk->flags) ? "un" : ""); printf("\tFragments are %spresent in the filesystem\n", SQUASHFS_NO_FRAGMENTS(sBlk->flags) ? "not " : ""); printf("\tAlways-use-fragments option is %sspecified\n", SQUASHFS_ALWAYS_FRAGMENTS(sBlk->flags) ? "" : "not "); printf("\tDuplicates are %sremoved\n", SQUASHFS_DUPLICATES(sBlk->flags) ? "" : "not "); printf("\tXattrs are %sstored\n", SQUASHFS_NO_XATTRS(sBlk->flags) ? "not " : ""); printf("\tFilesystem size %.2f Kbytes (%.2f Mbytes)\n", sBlk->bytes_used / 1024.0, sBlk->bytes_used / (1024.0 * 1024.0)); printf("\tBlock size %d\n", sBlk->block_size); printf("\tNumber of fragments %d\n", sBlk->fragments); printf("\tNumber of inodes %d\n", sBlk->inodes); printf("\tNumber of ids %d\n", sBlk->no_ids); TRACE("sBlk->inode_table_start %llx\n", sBlk->inode_table_start); TRACE("sBlk->directory_table_start %llx\n", sBlk->directory_table_start); TRACE("sBlk->id_table_start %llx\n", sBlk->id_table_start); TRACE("sBlk->fragment_table_start %llx\n", sBlk->fragment_table_start); TRACE("sBlk->lookup_table_start %llx\n", sBlk->lookup_table_start); TRACE("sBlk->xattr_id_table_start %llx\n", sBlk->xattr_id_table_start); printf("\n"); return comp; failed_mount: return NULL; }
static int squashfs_fill_super(struct super_block *sb, void *data, int silent) { struct squashfs_sb_info *msblk; struct squashfs_super_block *sblk = NULL; char b[BDEVNAME_SIZE]; struct inode *root; long long root_inode; unsigned short flags; unsigned int fragments; u64 lookup_table_start, xattr_id_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->devblksize = sb_min_blocksize(sb, SQUASHFS_DEVBLK_SIZE); msblk->devblksize_log2 = ffz(~msblk->devblksize); mutex_init(&msblk->read_data_mutex); 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 %s\n", bdevname(sb->s_bdev, b)); 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 > i_size_read(sb->s_bdev->bd_inode)) 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; } msblk->block_log = le16_to_cpu(sblk->block_log); if (msblk->block_log > SQUASHFS_FILE_MAX_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 %s\n", bdevname(sb->s_bdev, b)); 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; sb->s_op = &squashfs_super_ops; 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", 1, msblk->block_size); if (msblk->read_page == NULL) { ERROR("Failed to allocate read_page block\n"); goto failed_mount; } msblk->stream = squashfs_decompressor_init(sb, flags); if (IS_ERR(msblk->stream)) { err = PTR_ERR(msblk->stream); msblk->stream = NULL; goto failed_mount; } /* Handle xattrs */ #if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37) sb->s_xattr = (struct xattr_handler **) squashfs_xattr_handlers; #else sb->s_xattr = squashfs_xattr_handlers; #endif xattr_id_table_start = le64_to_cpu(sblk->xattr_id_table_start); if (xattr_id_table_start == SQUASHFS_INVALID_BLK) { next_table = msblk->bytes_used; goto allocate_id_index_table; } /* Allocate and read xattr id lookup table */ msblk->xattr_id_table = squashfs_read_xattr_id_table(sb, xattr_id_table_start, &msblk->xattr_table, &msblk->xattr_ids); if (IS_ERR(msblk->xattr_id_table)) { ERROR("unable to read xattr id index table\n"); err = PTR_ERR(msblk->xattr_id_table); msblk->xattr_id_table = NULL; if (err != -ENOTSUPP) goto failed_mount; } next_table = msblk->xattr_table; allocate_id_index_table: /* 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; /* Allocate and read inode lookup table */ msblk->inode_lookup_table = squashfs_read_inode_lookup_table(sb, lookup_table_start, next_table, msblk->inodes); if (IS_ERR(msblk->inode_lookup_table)) { ERROR("unable to read inode lookup table\n"); err = PTR_ERR(msblk->inode_lookup_table); msblk->inode_lookup_table = NULL; goto failed_mount; } next_table = le64_to_cpu(msblk->inode_lookup_table[0]); sb->s_export_op = &squashfs_export_ops; 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 = new_inode(sb); if (!root) { err = -ENOMEM; goto failed_mount; } err = squashfs_read_inode(root, root_inode); if (err) { make_bad_inode(root); iput(root); goto failed_mount; } insert_inode_hash(root); sb->s_root = d_alloc_root(root); if (sb->s_root == NULL) { ERROR("Root inode create failed\n"); err = -ENOMEM; iput(root); goto failed_mount; } TRACE("Leaving squashfs_fill_super\n"); 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_free(msblk, msblk->stream); 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; }
int read_super(int fd, squashfs_super_block *sBlk, int *be, char *source) { squashfs_super_block sblk; read_bytes(fd, SQUASHFS_START, sizeof(squashfs_super_block), (char *) sBlk); /* Check it is a SQUASHFS superblock */ swap = 0; switch (sBlk->s_magic) { case SQUASHFS_MAGIC_LZMA: if (!lzma) goto bad; break; case SQUASHFS_MAGIC: break; case SQUASHFS_MAGIC_SWAP: case SQUASHFS_MAGIC_LZMA_SWAP: ERROR("Reading a different endian SQUASHFS filesystem on %s - ignoring -le/-be options\n", source); SQUASHFS_SWAP_SUPER_BLOCK(&sblk, sBlk); memcpy(sBlk, &sblk, sizeof(squashfs_super_block)); swap = 1; break; bad: default: ERROR("Can't find a SQUASHFS superblock on %s\n", source); goto failed_mount; } /* Check the MAJOR & MINOR versions */ if(sBlk->s_major != SQUASHFS_MAJOR || sBlk->s_minor > SQUASHFS_MINOR) { if(sBlk->s_major < 3) ERROR("Filesystem on %s is a SQUASHFS %d.%d filesystem. Appending\nto SQUASHFS %d.%d filesystems is not supported. Please convert it to a SQUASHFS 3.0 filesystem\n", source, sBlk->s_major, sBlk->s_minor, sBlk->s_major, sBlk->s_minor); else ERROR("Major/Minor mismatch, filesystem on %s is %d.%d, I support 3.0\n", source, sBlk->s_major, sBlk->s_minor); goto failed_mount; } #if __BYTE_ORDER == __BIG_ENDIAN *be = !swap; #else *be = swap; #endif printf("Found a valid %s%s SQUASHFS superblock on %s.\n", SQUASHFS_EXPORTABLE(sBlk->flags) ? "exportable " : "", *be ? "big endian" : "little endian", source); printf("\tInodes are %scompressed\n", SQUASHFS_UNCOMPRESSED_INODES(sBlk->flags) ? "un" : ""); printf("\tData is %scompressed\n", SQUASHFS_UNCOMPRESSED_DATA(sBlk->flags) ? "un" : ""); printf("\tFragments are %scompressed\n", SQUASHFS_UNCOMPRESSED_FRAGMENTS(sBlk->flags) ? "un" : ""); printf("\tCheck data is %spresent in the filesystem\n", SQUASHFS_CHECK_DATA(sBlk->flags) ? "" : "not "); printf("\tFragments are %spresent in the filesystem\n", SQUASHFS_NO_FRAGMENTS(sBlk->flags) ? "not " : ""); printf("\tAlways_use_fragments option is %sspecified\n", SQUASHFS_ALWAYS_FRAGMENTS(sBlk->flags) ? "" : "not "); printf("\tDuplicates are %sremoved\n", SQUASHFS_DUPLICATES(sBlk->flags) ? "" : "not "); printf("\tFilesystem size %.2f Kbytes (%.2f Mbytes)\n", sBlk->bytes_used / 1024.0, sBlk->bytes_used / (1024.0 * 1024.0)); printf("\tBlock size %d\n", sBlk->block_size); printf("\tNumber of fragments %d\n", sBlk->fragments); printf("\tNumber of inodes %d\n", sBlk->inodes); printf("\tNumber of uids %d\n", sBlk->no_uids); printf("\tNumber of gids %d\n", sBlk->no_guids); TRACE("sBlk->inode_table_start %llx\n", sBlk->inode_table_start); TRACE("sBlk->directory_table_start %llx\n", sBlk->directory_table_start); TRACE("sBlk->uid_start %llx\n", sBlk->uid_start); TRACE("sBlk->fragment_table_start %llx\n", sBlk->fragment_table_start); TRACE("sBlk->lookup_table_start %xllx\n", sBlk->lookup_table_start); printf("\n"); return TRUE; failed_mount: return FALSE; }