static const char *ext4_encrypted_get_link(struct dentry *dentry, struct inode *inode, struct delayed_call *done) { struct page *cpage = NULL; char *caddr, *paddr = NULL; struct fscrypt_str cstr, pstr; struct fscrypt_symlink_data *sd; int res; u32 max_size = inode->i_sb->s_blocksize; if (!dentry) return ERR_PTR(-ECHILD); res = fscrypt_get_encryption_info(inode); if (res) return ERR_PTR(res); if (ext4_inode_is_fast_symlink(inode)) { caddr = (char *) EXT4_I(inode)->i_data; max_size = sizeof(EXT4_I(inode)->i_data); } else { cpage = read_mapping_page(inode->i_mapping, 0, NULL); if (IS_ERR(cpage)) return ERR_CAST(cpage); caddr = page_address(cpage); } /* Symlink is encrypted */ sd = (struct fscrypt_symlink_data *)caddr; cstr.name = sd->encrypted_path; cstr.len = le16_to_cpu(sd->len); if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > max_size) { /* Symlink data on the disk is corrupted */ res = -EFSCORRUPTED; goto errout; } res = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr); if (res) goto errout; paddr = pstr.name; res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr); if (res) goto errout; /* Null-terminate the name */ paddr[pstr.len] = '\0'; if (cpage) put_page(cpage); set_delayed_call(done, kfree_link, paddr); return paddr; errout: if (cpage) put_page(cpage); kfree(paddr); return ERR_PTR(res); }
/** * fscrypt_get_symlink - get the target of an encrypted symlink * @inode: the symlink inode * @caddr: the on-disk contents of the symlink * @max_size: size of @caddr buffer * @done: if successful, will be set up to free the returned target * * If the symlink's encryption key is available, we decrypt its target. * Otherwise, we encode its target for presentation. * * This may sleep, so the filesystem must have dropped out of RCU mode already. * * Return: the presentable symlink target or an ERR_PTR() */ const char *fscrypt_get_symlink(struct inode *inode, const void *caddr, unsigned int max_size, struct delayed_call *done) { const struct fscrypt_symlink_data *sd; struct fscrypt_str cstr, pstr; int err; /* This is for encrypted symlinks only */ if (WARN_ON(!IS_ENCRYPTED(inode))) return ERR_PTR(-EINVAL); /* * Try to set up the symlink's encryption key, but we can continue * regardless of whether the key is available or not. */ err = fscrypt_get_encryption_info(inode); if (err) return ERR_PTR(err); /* * For historical reasons, encrypted symlink targets are prefixed with * the ciphertext length, even though this is redundant with i_size. */ if (max_size < sizeof(*sd)) return ERR_PTR(-EUCLEAN); sd = caddr; cstr.name = (unsigned char *)sd->encrypted_path; cstr.len = le16_to_cpu(sd->len); if (cstr.len == 0) return ERR_PTR(-EUCLEAN); if (cstr.len + sizeof(*sd) - 1 > max_size) return ERR_PTR(-EUCLEAN); err = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr); if (err) return ERR_PTR(err); err = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr); if (err) goto err_kfree; err = -EUCLEAN; if (pstr.name[0] == '\0') goto err_kfree; pstr.name[pstr.len] = '\0'; set_delayed_call(done, kfree_link, pstr.name); return pstr.name; err_kfree: kfree(pstr.name); return ERR_PTR(err); }
static int ubifs_create(struct inode *dir, struct dentry *dentry, umode_t mode, bool excl) { struct inode *inode; struct ubifs_info *c = dir->i_sb->s_fs_info; struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1, .dirtied_ino = 1 }; struct ubifs_inode *dir_ui = ubifs_inode(dir); struct fscrypt_name nm; int err, sz_change; /* * Budget request settings: new inode, new direntry, changing the * parent directory inode. */ dbg_gen("dent '%pd', mode %#hx in dir ino %lu", dentry, mode, dir->i_ino); err = ubifs_budget_space(c, &req); if (err) return err; err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm); if (err) goto out_budg; sz_change = CALC_DENT_SIZE(fname_len(&nm)); inode = ubifs_new_inode(c, dir, mode); if (IS_ERR(inode)) { err = PTR_ERR(inode); goto out_fname; } err = ubifs_init_security(dir, inode, &dentry->d_name); if (err) goto out_inode; mutex_lock(&dir_ui->ui_mutex); dir->i_size += sz_change; dir_ui->ui_size = dir->i_size; dir->i_mtime = dir->i_ctime = inode->i_ctime; err = ubifs_jnl_update(c, dir, &nm, inode, 0, 0); if (err) goto out_cancel; mutex_unlock(&dir_ui->ui_mutex); ubifs_release_budget(c, &req); fscrypt_free_filename(&nm); insert_inode_hash(inode); d_instantiate(dentry, inode); return 0; out_cancel: dir->i_size -= sz_change; dir_ui->ui_size = dir->i_size; mutex_unlock(&dir_ui->ui_mutex); out_inode: make_bad_inode(inode); iput(inode); out_fname: fscrypt_free_filename(&nm); out_budg: ubifs_release_budget(c, &req); ubifs_err(c, "cannot create regular file, error %d", err); return err; } static int do_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode, struct inode **whiteout) { struct inode *inode; struct ubifs_info *c = dir->i_sb->s_fs_info; struct ubifs_budget_req req = { .new_ino = 1, .new_dent = 1}; struct ubifs_budget_req ino_req = { .dirtied_ino = 1 }; struct ubifs_inode *ui, *dir_ui = ubifs_inode(dir); int err, instantiated = 0; struct fscrypt_name nm; /* * Budget request settings: new dirty inode, new direntry, * budget for dirtied inode will be released via writeback. */ dbg_gen("dent '%pd', mode %#hx in dir ino %lu", dentry, mode, dir->i_ino); err = fscrypt_setup_filename(dir, &dentry->d_name, 0, &nm); if (err) return err; err = ubifs_budget_space(c, &req); if (err) { fscrypt_free_filename(&nm); return err; } err = ubifs_budget_space(c, &ino_req); if (err) { ubifs_release_budget(c, &req); fscrypt_free_filename(&nm); return err; } inode = ubifs_new_inode(c, dir, mode); if (IS_ERR(inode)) { err = PTR_ERR(inode); goto out_budg; } ui = ubifs_inode(inode); if (whiteout) { init_special_inode(inode, inode->i_mode, WHITEOUT_DEV); ubifs_assert(inode->i_op == &ubifs_file_inode_operations); } err = ubifs_init_security(dir, inode, &dentry->d_name); if (err) goto out_inode; mutex_lock(&ui->ui_mutex); insert_inode_hash(inode); if (whiteout) { mark_inode_dirty(inode); drop_nlink(inode); *whiteout = inode; } else { d_tmpfile(dentry, inode); } ubifs_assert(ui->dirty); instantiated = 1; mutex_unlock(&ui->ui_mutex); mutex_lock(&dir_ui->ui_mutex); err = ubifs_jnl_update(c, dir, &nm, inode, 1, 0); if (err) goto out_cancel; mutex_unlock(&dir_ui->ui_mutex); ubifs_release_budget(c, &req); return 0; out_cancel: mutex_unlock(&dir_ui->ui_mutex); out_inode: make_bad_inode(inode); if (!instantiated) iput(inode); out_budg: ubifs_release_budget(c, &req); if (!instantiated) ubifs_release_budget(c, &ino_req); fscrypt_free_filename(&nm); ubifs_err(c, "cannot create temporary file, error %d", err); return err; } static int ubifs_tmpfile(struct inode *dir, struct dentry *dentry, umode_t mode) { return do_tmpfile(dir, dentry, mode, NULL); } /** * vfs_dent_type - get VFS directory entry type. * @type: UBIFS directory entry type * * This function converts UBIFS directory entry type into VFS directory entry * type. */ static unsigned int vfs_dent_type(uint8_t type) { switch (type) { case UBIFS_ITYPE_REG: return DT_REG; case UBIFS_ITYPE_DIR: return DT_DIR; case UBIFS_ITYPE_LNK: return DT_LNK; case UBIFS_ITYPE_BLK: return DT_BLK; case UBIFS_ITYPE_CHR: return DT_CHR; case UBIFS_ITYPE_FIFO: return DT_FIFO; case UBIFS_ITYPE_SOCK: return DT_SOCK; default: BUG(); } return 0; } /* * The classical Unix view for directory is that it is a linear array of * (name, inode number) entries. Linux/VFS assumes this model as well. * Particularly, 'readdir()' call wants us to return a directory entry offset * which later may be used to continue 'readdir()'ing the directory or to * 'seek()' to that specific direntry. Obviously UBIFS does not really fit this * model because directory entries are identified by keys, which may collide. * * UBIFS uses directory entry hash value for directory offsets, so * 'seekdir()'/'telldir()' may not always work because of possible key * collisions. But UBIFS guarantees that consecutive 'readdir()' calls work * properly by means of saving full directory entry name in the private field * of the file description object. * * This means that UBIFS cannot support NFS which requires full * 'seekdir()'/'telldir()' support. */ static int ubifs_readdir(struct file *file, struct dir_context *ctx) { int fstr_real_len = 0, err = 0; struct fscrypt_name nm; struct fscrypt_str fstr = {0}; union ubifs_key key; struct ubifs_dent_node *dent; struct inode *dir = file_inode(file); struct ubifs_info *c = dir->i_sb->s_fs_info; bool encrypted = ubifs_crypt_is_encrypted(dir); dbg_gen("dir ino %lu, f_pos %#llx", dir->i_ino, ctx->pos); if (ctx->pos > UBIFS_S_KEY_HASH_MASK || ctx->pos == 2) /* * The directory was seek'ed to a senseless position or there * are no more entries. */ return 0; if (encrypted) { err = fscrypt_get_encryption_info(dir); if (err && err != -ENOKEY) return err; err = fscrypt_fname_alloc_buffer(dir, UBIFS_MAX_NLEN, &fstr); if (err) return err; fstr_real_len = fstr.len; } if (file->f_version == 0) { /* * The file was seek'ed, which means that @file->private_data * is now invalid. This may also be just the first * 'ubifs_readdir()' invocation, in which case * @file->private_data is NULL, and the below code is * basically a no-op. */ kfree(file->private_data); file->private_data = NULL; } /* * 'generic_file_llseek()' unconditionally sets @file->f_version to * zero, and we use this for detecting whether the file was seek'ed. */ file->f_version = 1; /* File positions 0 and 1 correspond to "." and ".." */ if (ctx->pos < 2) { ubifs_assert(!file->private_data); if (!dir_emit_dots(file, ctx)) { if (encrypted) fscrypt_fname_free_buffer(&fstr); return 0; } /* Find the first entry in TNC and save it */ lowest_dent_key(c, &key, dir->i_ino); fname_len(&nm) = 0; dent = ubifs_tnc_next_ent(c, &key, &nm); if (IS_ERR(dent)) { err = PTR_ERR(dent); goto out; } ctx->pos = key_hash_flash(c, &dent->key); file->private_data = dent; } dent = file->private_data; if (!dent) { /* * The directory was seek'ed to and is now readdir'ed. * Find the entry corresponding to @ctx->pos or the closest one. */ dent_key_init_hash(c, &key, dir->i_ino, ctx->pos); fname_len(&nm) = 0; dent = ubifs_tnc_next_ent(c, &key, &nm); if (IS_ERR(dent)) { err = PTR_ERR(dent); goto out; } ctx->pos = key_hash_flash(c, &dent->key); file->private_data = dent; } while (1) { dbg_gen("ino %llu, new f_pos %#x", (unsigned long long)le64_to_cpu(dent->inum), key_hash_flash(c, &dent->key)); ubifs_assert(le64_to_cpu(dent->ch.sqnum) > ubifs_inode(dir)->creat_sqnum); fname_len(&nm) = le16_to_cpu(dent->nlen); fname_name(&nm) = dent->name; if (encrypted) { fstr.len = fstr_real_len; err = fscrypt_fname_disk_to_usr(dir, key_hash_flash(c, &dent->key), le32_to_cpu(dent->cookie), &nm.disk_name, &fstr); if (err) goto out; } else { fstr.len = fname_len(&nm); fstr.name = fname_name(&nm); } if (!dir_emit(ctx, fstr.name, fstr.len, le64_to_cpu(dent->inum), vfs_dent_type(dent->type))) { if (encrypted) fscrypt_fname_free_buffer(&fstr); return 0; } /* Switch to the next entry */ key_read(c, &dent->key, &key); dent = ubifs_tnc_next_ent(c, &key, &nm); if (IS_ERR(dent)) { err = PTR_ERR(dent); goto out; } kfree(file->private_data); ctx->pos = key_hash_flash(c, &dent->key); file->private_data = dent; cond_resched(); } out: kfree(file->private_data); file->private_data = NULL; if (encrypted) fscrypt_fname_free_buffer(&fstr); if (err != -ENOENT) ubifs_err(c, "cannot find next direntry, error %d", err); else /* * -ENOENT is a non-fatal error in this context, the TNC uses * it to indicate that the cursor moved past the current directory * and readdir() has to stop. */ err = 0; /* 2 is a special value indicating that there are no more direntries */ ctx->pos = 2; return err; } /* Free saved readdir() state when the directory is closed */ static int ubifs_dir_release(struct inode *dir, struct file *file) { kfree(file->private_data); file->private_data = NULL; return 0; } /** * lock_2_inodes - a wrapper for locking two UBIFS inodes. * @inode1: first inode * @inode2: second inode * * We do not implement any tricks to guarantee strict lock ordering, because * VFS has already done it for us on the @i_mutex. So this is just a simple * wrapper function. */ static void lock_2_inodes(struct inode *inode1, struct inode *inode2) { mutex_lock_nested(&ubifs_inode(inode1)->ui_mutex, WB_MUTEX_1); mutex_lock_nested(&ubifs_inode(inode2)->ui_mutex, WB_MUTEX_2); }
struct dentry *f2fs_get_parent(struct dentry *child) { struct qstr dotdot = {.len = 2, .name = ".."}; struct page *page; unsigned long ino = f2fs_inode_by_name(d_inode(child), &dotdot, &page); if (!ino) { if (IS_ERR(page)) return ERR_CAST(page); return ERR_PTR(-ENOENT); } return d_obtain_alias(f2fs_iget(child->d_sb, ino)); } static int __recover_dot_dentries(struct inode *dir, nid_t pino) { struct f2fs_sb_info *sbi = F2FS_I_SB(dir); struct qstr dot = QSTR_INIT(".", 1); struct qstr dotdot = QSTR_INIT("..", 2); struct f2fs_dir_entry *de; struct page *page; int err = 0; if (f2fs_readonly(sbi->sb)) { f2fs_msg(sbi->sb, KERN_INFO, "skip recovering inline_dots inode (ino:%lu, pino:%u) " "in readonly mountpoint", dir->i_ino, pino); return 0; } f2fs_balance_fs(sbi, true); f2fs_lock_op(sbi); de = f2fs_find_entry(dir, &dot, &page); if (de) { f2fs_dentry_kunmap(dir, page); f2fs_put_page(page, 0); } else if (IS_ERR(page)) { err = PTR_ERR(page); goto out; } else { err = __f2fs_add_link(dir, &dot, NULL, dir->i_ino, S_IFDIR); if (err) goto out; } de = f2fs_find_entry(dir, &dotdot, &page); if (de) { f2fs_dentry_kunmap(dir, page); f2fs_put_page(page, 0); } else if (IS_ERR(page)) { err = PTR_ERR(page); } else { err = __f2fs_add_link(dir, &dotdot, NULL, pino, S_IFDIR); } out: if (!err) clear_inode_flag(dir, FI_INLINE_DOTS); f2fs_unlock_op(sbi); return err; } static struct dentry *f2fs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) { struct inode *inode = NULL; struct f2fs_dir_entry *de; struct page *page; nid_t ino; int err = 0; unsigned int root_ino = F2FS_ROOT_INO(F2FS_I_SB(dir)); if (f2fs_encrypted_inode(dir)) { int res = fscrypt_get_encryption_info(dir); /* * DCACHE_ENCRYPTED_WITH_KEY is set if the dentry is * created while the directory was encrypted and we * don't have access to the key. */ if (fscrypt_has_encryption_key(dir)) fscrypt_set_encrypted_dentry(dentry); fscrypt_set_d_op(dentry); if (res && res != -ENOKEY) return ERR_PTR(res); } if (dentry->d_name.len > F2FS_NAME_LEN) return ERR_PTR(-ENAMETOOLONG); de = f2fs_find_entry(dir, &dentry->d_name, &page); if (!de) { if (IS_ERR(page)) return (struct dentry *)page; return d_splice_alias(inode, dentry); } ino = le32_to_cpu(de->ino); f2fs_dentry_kunmap(dir, page); f2fs_put_page(page, 0); inode = f2fs_iget(dir->i_sb, ino); if (IS_ERR(inode)) return ERR_CAST(inode); if ((dir->i_ino == root_ino) && f2fs_has_inline_dots(dir)) { err = __recover_dot_dentries(dir, root_ino); if (err) goto err_out; } if (f2fs_has_inline_dots(inode)) { err = __recover_dot_dentries(inode, dir->i_ino); if (err) goto err_out; } if (!IS_ERR(inode) && f2fs_encrypted_inode(dir) && (S_ISDIR(inode->i_mode) || S_ISLNK(inode->i_mode)) && !fscrypt_has_permitted_context(dir, inode)) { bool nokey = f2fs_encrypted_inode(inode) && !fscrypt_has_encryption_key(inode); err = nokey ? -ENOKEY : -EPERM; goto err_out; } return d_splice_alias(inode, dentry); err_out: iput(inode); return ERR_PTR(err); } static int f2fs_unlink(struct inode *dir, struct dentry *dentry) { struct f2fs_sb_info *sbi = F2FS_I_SB(dir); struct inode *inode = d_inode(dentry); struct f2fs_dir_entry *de; struct page *page; int err = -ENOENT; trace_f2fs_unlink_enter(dir, dentry); de = f2fs_find_entry(dir, &dentry->d_name, &page); if (!de) { if (IS_ERR(page)) err = PTR_ERR(page); goto fail; } f2fs_balance_fs(sbi, true); f2fs_lock_op(sbi); err = acquire_orphan_inode(sbi); if (err) { f2fs_unlock_op(sbi); f2fs_dentry_kunmap(dir, page); f2fs_put_page(page, 0); goto fail; } f2fs_delete_entry(de, page, dir, inode); f2fs_unlock_op(sbi); if (IS_DIRSYNC(dir)) f2fs_sync_fs(sbi->sb, 1); fail: trace_f2fs_unlink_exit(inode, err); return err; } static void *f2fs_follow_link(struct dentry *dentry, struct nameidata *nd) { struct page *page; char *link; page = page_follow_link_light(dentry, nd); if (IS_ERR(page)) return page; link = nd_get_link(nd); if (IS_ERR(link)) return link; /* this is broken symlink case */ if (*link == 0) { kunmap(page); page_cache_release(page); return ERR_PTR(-ENOENT); } return page; } static int f2fs_symlink(struct inode *dir, struct dentry *dentry, const char *symname) { struct f2fs_sb_info *sbi = F2FS_I_SB(dir); struct inode *inode; size_t len = strlen(symname); struct fscrypt_str disk_link = FSTR_INIT((char *)symname, len + 1); struct fscrypt_symlink_data *sd = NULL; int err; if (f2fs_encrypted_inode(dir)) { err = fscrypt_get_encryption_info(dir); if (err) return err; if (!fscrypt_has_encryption_key(dir)) return -EPERM; disk_link.len = (fscrypt_fname_encrypted_size(dir, len) + sizeof(struct fscrypt_symlink_data)); } if (disk_link.len > dir->i_sb->s_blocksize) return -ENAMETOOLONG; inode = f2fs_new_inode(dir, S_IFLNK | S_IRWXUGO); if (IS_ERR(inode)) return PTR_ERR(inode); if (f2fs_encrypted_inode(inode)) inode->i_op = &f2fs_encrypted_symlink_inode_operations; else inode->i_op = &f2fs_symlink_inode_operations; inode_nohighmem(inode); inode->i_mapping->a_ops = &f2fs_dblock_aops; f2fs_balance_fs(sbi, true); f2fs_lock_op(sbi); err = f2fs_add_link(dentry, inode); if (err) goto out; f2fs_unlock_op(sbi); alloc_nid_done(sbi, inode->i_ino); if (f2fs_encrypted_inode(inode)) { struct qstr istr = QSTR_INIT(symname, len); struct fscrypt_str ostr; sd = kzalloc(disk_link.len, GFP_NOFS); if (!sd) { err = -ENOMEM; goto err_out; } err = fscrypt_get_encryption_info(inode); if (err) goto err_out; if (!fscrypt_has_encryption_key(inode)) { err = -EPERM; goto err_out; } ostr.name = sd->encrypted_path; ostr.len = disk_link.len; err = fscrypt_fname_usr_to_disk(inode, &istr, &ostr); if (err < 0) goto err_out; sd->len = cpu_to_le16(ostr.len); disk_link.name = (char *)sd; } err = page_symlink(inode, disk_link.name, disk_link.len); err_out: d_instantiate(dentry, inode); unlock_new_inode(inode); /* * Let's flush symlink data in order to avoid broken symlink as much as * possible. Nevertheless, fsyncing is the best way, but there is no * way to get a file descriptor in order to flush that. * * Note that, it needs to do dir->fsync to make this recoverable. * If the symlink path is stored into inline_data, there is no * performance regression. */ if (!err) { filemap_write_and_wait_range(inode->i_mapping, 0, disk_link.len - 1); if (IS_DIRSYNC(dir)) f2fs_sync_fs(sbi->sb, 1); } else { f2fs_unlink(dir, dentry); } kfree(sd); return err; out: handle_failed_inode(inode); return err; } static int f2fs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) { struct f2fs_sb_info *sbi = F2FS_I_SB(dir); struct inode *inode; int err; inode = f2fs_new_inode(dir, S_IFDIR | mode); if (IS_ERR(inode)) return PTR_ERR(inode); inode->i_op = &f2fs_dir_inode_operations; inode->i_fop = &f2fs_dir_operations; inode->i_mapping->a_ops = &f2fs_dblock_aops; mapping_set_gfp_mask(inode->i_mapping, GFP_F2FS_HIGH_ZERO); f2fs_balance_fs(sbi, true); set_inode_flag(inode, FI_INC_LINK); f2fs_lock_op(sbi); err = f2fs_add_link(dentry, inode); if (err) goto out_fail; f2fs_unlock_op(sbi); alloc_nid_done(sbi, inode->i_ino); d_instantiate(dentry, inode); unlock_new_inode(inode); if (IS_DIRSYNC(dir)) f2fs_sync_fs(sbi->sb, 1); return 0; out_fail: clear_inode_flag(inode, FI_INC_LINK); handle_failed_inode(inode); return err; } static int f2fs_rmdir(struct inode *dir, struct dentry *dentry) { struct inode *inode = d_inode(dentry); if (f2fs_empty_dir(inode)) return f2fs_unlink(dir, dentry); return -ENOTEMPTY; } static int f2fs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev) { struct f2fs_sb_info *sbi = F2FS_I_SB(dir); struct inode *inode; int err = 0; if (!new_valid_dev(rdev)) return -EINVAL; inode = f2fs_new_inode(dir, mode); if (IS_ERR(inode)) return PTR_ERR(inode); init_special_inode(inode, inode->i_mode, rdev); inode->i_op = &f2fs_special_inode_operations; f2fs_balance_fs(sbi, true); f2fs_lock_op(sbi); err = f2fs_add_link(dentry, inode); if (err) goto out; f2fs_unlock_op(sbi); alloc_nid_done(sbi, inode->i_ino); d_instantiate(dentry, inode); unlock_new_inode(inode); if (IS_DIRSYNC(dir)) f2fs_sync_fs(sbi->sb, 1); return 0; out: handle_failed_inode(inode); return err; } static int f2fs_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry) { struct f2fs_sb_info *sbi = F2FS_I_SB(old_dir); struct inode *old_inode = d_inode(old_dentry); struct inode *new_inode = d_inode(new_dentry); struct page *old_dir_page; struct page *old_page, *new_page; struct f2fs_dir_entry *old_dir_entry = NULL; struct f2fs_dir_entry *old_entry; struct f2fs_dir_entry *new_entry; bool is_old_inline = f2fs_has_inline_dentry(old_dir); int err = -ENOENT; if ((old_dir != new_dir) && f2fs_encrypted_inode(new_dir) && !fscrypt_has_permitted_context(new_dir, old_inode)) { err = -EPERM; goto out; } old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page); if (!old_entry) { if (IS_ERR(old_page)) err = PTR_ERR(old_page); goto out; } if (S_ISDIR(old_inode->i_mode)) { old_dir_entry = f2fs_parent_dir(old_inode, &old_dir_page); if (!old_dir_entry) { if (IS_ERR(old_dir_page)) err = PTR_ERR(old_dir_page); goto out_old; } } if (new_inode) { err = -ENOTEMPTY; if (old_dir_entry && !f2fs_empty_dir(new_inode)) goto out_dir; err = -ENOENT; new_entry = f2fs_find_entry(new_dir, &new_dentry->d_name, &new_page); if (!new_entry) { if (IS_ERR(new_page)) err = PTR_ERR(new_page); goto out_dir; } f2fs_balance_fs(sbi, true); f2fs_lock_op(sbi); err = acquire_orphan_inode(sbi); if (err) goto put_out_dir; err = update_dent_inode(old_inode, new_inode, &new_dentry->d_name); if (err) { release_orphan_inode(sbi); goto put_out_dir; } f2fs_set_link(new_dir, new_entry, new_page, old_inode); new_inode->i_ctime = CURRENT_TIME; down_write(&F2FS_I(new_inode)->i_sem); if (old_dir_entry) f2fs_i_links_write(new_inode, false); f2fs_i_links_write(new_inode, false); up_write(&F2FS_I(new_inode)->i_sem); if (!new_inode->i_nlink) add_orphan_inode(new_inode); else release_orphan_inode(sbi); } else { f2fs_balance_fs(sbi, true); f2fs_lock_op(sbi); err = f2fs_add_link(new_dentry, old_inode); if (err) { f2fs_unlock_op(sbi); goto out_dir; } if (old_dir_entry) f2fs_i_links_write(new_dir, true); /* * old entry and new entry can locate in the same inline * dentry in inode, when attaching new entry in inline dentry, * it could force inline dentry conversion, after that, * old_entry and old_page will point to wrong address, in * order to avoid this, let's do the check and update here. */ if (is_old_inline && !f2fs_has_inline_dentry(old_dir)) { f2fs_put_page(old_page, 0); old_page = NULL; old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page); if (!old_entry) { err = -ENOENT; if (IS_ERR(old_page)) err = PTR_ERR(old_page); f2fs_unlock_op(sbi); goto out_dir; } } } down_write(&F2FS_I(old_inode)->i_sem); file_lost_pino(old_inode); if (new_inode && file_enc_name(new_inode)) file_set_enc_name(old_inode); up_write(&F2FS_I(old_inode)->i_sem); old_inode->i_ctime = CURRENT_TIME; f2fs_mark_inode_dirty_sync(old_inode); f2fs_delete_entry(old_entry, old_page, old_dir, NULL); if (old_dir_entry) { if (old_dir != new_dir) { f2fs_set_link(old_inode, old_dir_entry, old_dir_page, new_dir); } else { f2fs_dentry_kunmap(old_inode, old_dir_page); f2fs_put_page(old_dir_page, 0); } f2fs_i_links_write(old_dir, false); } f2fs_unlock_op(sbi); if (IS_DIRSYNC(old_dir) || IS_DIRSYNC(new_dir)) f2fs_sync_fs(sbi->sb, 1); return 0; put_out_dir: f2fs_unlock_op(sbi); f2fs_dentry_kunmap(new_dir, new_page); f2fs_put_page(new_page, 0); out_dir: if (old_dir_entry) { f2fs_dentry_kunmap(old_inode, old_dir_page); f2fs_put_page(old_dir_page, 0); } out_old: f2fs_dentry_kunmap(old_dir, old_page); f2fs_put_page(old_page, 0); out: return err; } static void *f2fs_encrypted_follow_link(struct dentry *dentry, struct nameidata *nd) { struct page *cpage = NULL; char *caddr, *paddr = NULL; struct fscrypt_str cstr = FSTR_INIT(NULL, 0); struct fscrypt_str pstr = FSTR_INIT(NULL, 0); struct fscrypt_symlink_data *sd; struct inode *inode = d_inode(dentry); loff_t size = min_t(loff_t, i_size_read(inode), PAGE_SIZE - 1); u32 max_size = inode->i_sb->s_blocksize; int res; res = fscrypt_get_encryption_info(inode); if (res) return ERR_PTR(res); cpage = read_mapping_page(inode->i_mapping, 0, NULL); if (IS_ERR(cpage)) return cpage; caddr = kmap(cpage); caddr[size] = 0; /* Symlink is encrypted */ sd = (struct fscrypt_symlink_data *)caddr; cstr.name = sd->encrypted_path; cstr.len = le16_to_cpu(sd->len); /* this is broken symlink case */ if (unlikely(cstr.len == 0)) { res = -ENOENT; goto errout; } if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > max_size) { /* Symlink data on the disk is corrupted */ res = -EIO; goto errout; } res = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr); if (res) goto errout; res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr); if (res < 0) goto errout; /* this is broken symlink case */ if (unlikely(pstr.name[0] == 0)) { res = -ENOENT; goto errout; } paddr = pstr.name; /* Null-terminate the name */ paddr[res] = '\0'; nd_set_link(nd, paddr); kunmap(cpage); page_cache_release(cpage); return NULL; errout: fscrypt_fname_free_buffer(&pstr); kunmap(cpage); page_cache_release(cpage); return ERR_PTR(res); } void kfree_put_link(struct dentry *dentry, struct nameidata *nd, void *cookie) { char *s = nd_get_link(nd); if (!IS_ERR(s)) kfree(s); }
static const char *f2fs_encrypted_get_link(struct dentry *dentry, struct inode *inode, struct delayed_call *done) { struct page *cpage = NULL; char *caddr, *paddr = NULL; struct fscrypt_str cstr = FSTR_INIT(NULL, 0); struct fscrypt_str pstr = FSTR_INIT(NULL, 0); struct fscrypt_symlink_data *sd; u32 max_size = inode->i_sb->s_blocksize; int res; if (!dentry) return ERR_PTR(-ECHILD); res = fscrypt_get_encryption_info(inode); if (res) return ERR_PTR(res); cpage = read_mapping_page(inode->i_mapping, 0, NULL); if (IS_ERR(cpage)) return ERR_CAST(cpage); caddr = page_address(cpage); /* Symlink is encrypted */ sd = (struct fscrypt_symlink_data *)caddr; cstr.name = sd->encrypted_path; cstr.len = le16_to_cpu(sd->len); /* this is broken symlink case */ if (unlikely(cstr.len == 0)) { res = -ENOENT; goto errout; } if ((cstr.len + sizeof(struct fscrypt_symlink_data) - 1) > max_size) { /* Symlink data on the disk is corrupted */ res = -EIO; goto errout; } res = fscrypt_fname_alloc_buffer(inode, cstr.len, &pstr); if (res) goto errout; res = fscrypt_fname_disk_to_usr(inode, 0, 0, &cstr, &pstr); if (res) goto errout; /* this is broken symlink case */ if (unlikely(pstr.name[0] == 0)) { res = -ENOENT; goto errout; } paddr = pstr.name; /* Null-terminate the name */ paddr[pstr.len] = '\0'; put_page(cpage); set_delayed_call(done, kfree_link, paddr); return paddr; errout: fscrypt_fname_free_buffer(&pstr); put_page(cpage); return ERR_PTR(res); }