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- // SPDX-License-Identifier: GPL-2.0
- /*
- * Copyright 2020 Google LLC
- */
- #include <linux/file.h>
- #include <linux/fs.h>
- #include <linux/fsnotify.h>
- #include <linux/namei.h>
- #include <linux/poll.h>
- #include <linux/syscalls.h>
- #include <uapi/linux/incrementalfs.h>
- #include "pseudo_files.h"
- #include "data_mgmt.h"
- #include "format.h"
- #include "integrity.h"
- #include "vfs.h"
- #define READ_WRITE_FILE_MODE 0666
- static bool is_pseudo_filename(struct mem_range name);
- /*******************************************************************************
- * .pending_reads pseudo file definition
- ******************************************************************************/
- #define INCFS_PENDING_READS_INODE 2
- static const char pending_reads_file_name[] = INCFS_PENDING_READS_FILENAME;
- /* State of an open .pending_reads file, unique for each file descriptor. */
- struct pending_reads_state {
- /* A serial number of the last pending read obtained from this file. */
- int last_pending_read_sn;
- };
- static ssize_t pending_reads_read(struct file *f, char __user *buf, size_t len,
- loff_t *ppos)
- {
- struct pending_reads_state *pr_state = f->private_data;
- struct mount_info *mi = get_mount_info(file_superblock(f));
- bool report_uid;
- unsigned long page = 0;
- struct incfs_pending_read_info *reads_buf = NULL;
- struct incfs_pending_read_info2 *reads_buf2 = NULL;
- size_t record_size;
- size_t reads_to_collect;
- int last_known_read_sn = READ_ONCE(pr_state->last_pending_read_sn);
- int new_max_sn = last_known_read_sn;
- int reads_collected = 0;
- ssize_t result = 0;
- if (!mi)
- return -EFAULT;
- report_uid = mi->mi_options.report_uid;
- record_size = report_uid ? sizeof(*reads_buf2) : sizeof(*reads_buf);
- reads_to_collect = len / record_size;
- if (!incfs_fresh_pending_reads_exist(mi, last_known_read_sn))
- return 0;
- page = get_zeroed_page(GFP_NOFS);
- if (!page)
- return -ENOMEM;
- if (report_uid)
- reads_buf2 = (struct incfs_pending_read_info2 *) page;
- else
- reads_buf = (struct incfs_pending_read_info *) page;
- reads_to_collect =
- min_t(size_t, PAGE_SIZE / record_size, reads_to_collect);
- reads_collected = incfs_collect_pending_reads(mi, last_known_read_sn,
- reads_buf, reads_buf2, reads_to_collect,
- &new_max_sn);
- if (reads_collected < 0) {
- result = reads_collected;
- goto out;
- }
- /*
- * Just to make sure that we don't accidentally copy more data
- * to reads buffer than userspace can handle.
- */
- reads_collected = min_t(size_t, reads_collected, reads_to_collect);
- result = reads_collected * record_size;
- /* Copy reads info to the userspace buffer */
- if (copy_to_user(buf, (void *)page, result)) {
- result = -EFAULT;
- goto out;
- }
- WRITE_ONCE(pr_state->last_pending_read_sn, new_max_sn);
- *ppos = 0;
- out:
- free_page(page);
- return result;
- }
- static __poll_t pending_reads_poll(struct file *file, poll_table *wait)
- {
- struct pending_reads_state *state = file->private_data;
- struct mount_info *mi = get_mount_info(file_superblock(file));
- __poll_t ret = 0;
- poll_wait(file, &mi->mi_pending_reads_notif_wq, wait);
- if (incfs_fresh_pending_reads_exist(mi,
- state->last_pending_read_sn))
- ret = EPOLLIN | EPOLLRDNORM;
- return ret;
- }
- static int pending_reads_open(struct inode *inode, struct file *file)
- {
- struct pending_reads_state *state = NULL;
- state = kzalloc(sizeof(*state), GFP_NOFS);
- if (!state)
- return -ENOMEM;
- file->private_data = state;
- return 0;
- }
- static int pending_reads_release(struct inode *inode, struct file *file)
- {
- kfree(file->private_data);
- return 0;
- }
- static long ioctl_permit_fill(struct file *f, void __user *arg)
- {
- struct incfs_permit_fill __user *usr_permit_fill = arg;
- struct incfs_permit_fill permit_fill;
- long error = 0;
- struct file *file = NULL;
- struct incfs_file_data *fd;
- if (copy_from_user(&permit_fill, usr_permit_fill, sizeof(permit_fill)))
- return -EFAULT;
- file = fget(permit_fill.file_descriptor);
- if (IS_ERR_OR_NULL(file)) {
- if (!file)
- return -ENOENT;
- return PTR_ERR(file);
- }
- if (file->f_op != &incfs_file_ops) {
- error = -EPERM;
- goto out;
- }
- if (file->f_inode->i_sb != f->f_inode->i_sb) {
- error = -EPERM;
- goto out;
- }
- fd = file->private_data;
- switch (fd->fd_fill_permission) {
- case CANT_FILL:
- fd->fd_fill_permission = CAN_FILL;
- break;
- case CAN_FILL:
- pr_debug("CAN_FILL already set");
- break;
- default:
- pr_warn("Invalid file private data");
- error = -EFAULT;
- goto out;
- }
- out:
- fput(file);
- return error;
- }
- static int chmod(struct dentry *dentry, umode_t mode)
- {
- struct inode *inode = dentry->d_inode;
- struct inode *delegated_inode = NULL;
- struct iattr newattrs;
- int error;
- retry_deleg:
- inode_lock(inode);
- newattrs.ia_mode = (mode & S_IALLUGO) | (inode->i_mode & ~S_IALLUGO);
- newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
- error = notify_change(dentry, &newattrs, &delegated_inode);
- inode_unlock(inode);
- if (delegated_inode) {
- error = break_deleg_wait(&delegated_inode);
- if (!error)
- goto retry_deleg;
- }
- return error;
- }
- static bool incfs_equal_ranges(struct mem_range lhs, struct mem_range rhs)
- {
- if (lhs.len != rhs.len)
- return false;
- return memcmp(lhs.data, rhs.data, lhs.len) == 0;
- }
- static int validate_name(char *file_name)
- {
- struct mem_range name = range(file_name, strlen(file_name));
- int i = 0;
- if (name.len > INCFS_MAX_NAME_LEN)
- return -ENAMETOOLONG;
- if (is_pseudo_filename(name))
- return -EINVAL;
- for (i = 0; i < name.len; i++)
- if (name.data[i] == '/')
- return -EINVAL;
- return 0;
- }
- static int dir_relative_path_resolve(
- struct mount_info *mi,
- const char __user *relative_path,
- struct path *result_path,
- struct path *base_path)
- {
- int dir_fd = get_unused_fd_flags(0);
- struct file *dir_f = NULL;
- int error = 0;
- if (!base_path)
- base_path = &mi->mi_backing_dir_path;
- if (dir_fd < 0)
- return dir_fd;
- dir_f = dentry_open(base_path, O_RDONLY | O_NOATIME, current_cred());
- if (IS_ERR(dir_f)) {
- error = PTR_ERR(dir_f);
- goto out;
- }
- fd_install(dir_fd, dir_f);
- if (!relative_path) {
- /* No relative path given, just return the base dir. */
- *result_path = *base_path;
- path_get(result_path);
- goto out;
- }
- error = user_path_at_empty(dir_fd, relative_path,
- LOOKUP_FOLLOW | LOOKUP_DIRECTORY, result_path, NULL);
- out:
- ksys_close(dir_fd);
- if (error)
- pr_debug("Error: %d\n", error);
- return error;
- }
- static struct mem_range incfs_copy_signature_info_from_user(u8 __user *original,
- u64 size)
- {
- u8 *result;
- if (!original)
- return range(NULL, 0);
- if (size > INCFS_MAX_SIGNATURE_SIZE)
- return range(ERR_PTR(-EFAULT), 0);
- result = kzalloc(size, GFP_NOFS | __GFP_COMP);
- if (!result)
- return range(ERR_PTR(-ENOMEM), 0);
- if (copy_from_user(result, original, size)) {
- kfree(result);
- return range(ERR_PTR(-EFAULT), 0);
- }
- return range(result, size);
- }
- static int init_new_file(struct mount_info *mi, struct dentry *dentry,
- incfs_uuid_t *uuid, u64 size, struct mem_range attr,
- u8 __user *user_signature_info, u64 signature_size)
- {
- struct path path = {};
- struct file *new_file;
- int error = 0;
- struct backing_file_context *bfc = NULL;
- u32 block_count;
- struct mem_range raw_signature = { NULL };
- struct mtree *hash_tree = NULL;
- if (!mi || !dentry || !uuid)
- return -EFAULT;
- /* Resize newly created file to its true size. */
- path = (struct path) {
- .mnt = mi->mi_backing_dir_path.mnt,
- .dentry = dentry
- };
- new_file = dentry_open(&path, O_RDWR | O_NOATIME | O_LARGEFILE,
- current_cred());
- if (IS_ERR(new_file)) {
- error = PTR_ERR(new_file);
- goto out;
- }
- bfc = incfs_alloc_bfc(mi, new_file);
- fput(new_file);
- if (IS_ERR(bfc)) {
- error = PTR_ERR(bfc);
- bfc = NULL;
- goto out;
- }
- mutex_lock(&bfc->bc_mutex);
- error = incfs_write_fh_to_backing_file(bfc, uuid, size);
- if (error)
- goto out;
- block_count = (u32)get_blocks_count_for_size(size);
- if (user_signature_info) {
- raw_signature = incfs_copy_signature_info_from_user(
- user_signature_info, signature_size);
- if (IS_ERR(raw_signature.data)) {
- error = PTR_ERR(raw_signature.data);
- raw_signature.data = NULL;
- goto out;
- }
- hash_tree = incfs_alloc_mtree(raw_signature, block_count);
- if (IS_ERR(hash_tree)) {
- error = PTR_ERR(hash_tree);
- hash_tree = NULL;
- goto out;
- }
- error = incfs_write_signature_to_backing_file(bfc,
- raw_signature, hash_tree->hash_tree_area_size,
- NULL, NULL);
- if (error)
- goto out;
- block_count += get_blocks_count_for_size(
- hash_tree->hash_tree_area_size);
- }
- if (block_count)
- error = incfs_write_blockmap_to_backing_file(bfc, block_count);
- if (error)
- goto out;
- out:
- if (bfc) {
- mutex_unlock(&bfc->bc_mutex);
- incfs_free_bfc(bfc);
- }
- incfs_free_mtree(hash_tree);
- kfree(raw_signature.data);
- if (error)
- pr_debug("incfs: %s error: %d\n", __func__, error);
- return error;
- }
- static void notify_create(struct file *pending_reads_file,
- const char __user *dir_name, const char *file_name,
- const char *file_id_str, bool incomplete_file)
- {
- struct mount_info *mi =
- get_mount_info(file_superblock(pending_reads_file));
- struct path base_path = {
- .mnt = pending_reads_file->f_path.mnt,
- .dentry = pending_reads_file->f_path.dentry->d_parent,
- };
- struct path dir_path = {};
- struct dentry *file = NULL;
- struct dentry *dir = NULL;
- int error;
- error = dir_relative_path_resolve(mi, dir_name, &dir_path, &base_path);
- if (error)
- goto out;
- file = incfs_lookup_dentry(dir_path.dentry, file_name);
- if (IS_ERR(file)) {
- error = PTR_ERR(file);
- file = NULL;
- goto out;
- }
- fsnotify_create(d_inode(dir_path.dentry), file);
- if (file_id_str) {
- dir = incfs_lookup_dentry(base_path.dentry, INCFS_INDEX_NAME);
- if (IS_ERR(dir)) {
- error = PTR_ERR(dir);
- dir = NULL;
- goto out;
- }
- dput(file);
- file = incfs_lookup_dentry(dir, file_id_str);
- if (IS_ERR(file)) {
- error = PTR_ERR(file);
- file = NULL;
- goto out;
- }
- fsnotify_create(d_inode(dir), file);
- if (incomplete_file) {
- dput(dir);
- dir = incfs_lookup_dentry(base_path.dentry,
- INCFS_INCOMPLETE_NAME);
- if (IS_ERR(dir)) {
- error = PTR_ERR(dir);
- dir = NULL;
- goto out;
- }
- dput(file);
- file = incfs_lookup_dentry(dir, file_id_str);
- if (IS_ERR(file)) {
- error = PTR_ERR(file);
- file = NULL;
- goto out;
- }
- fsnotify_create(d_inode(dir), file);
- }
- }
- out:
- if (error)
- pr_warn("%s failed with error %d\n", __func__, error);
- dput(dir);
- dput(file);
- path_put(&dir_path);
- }
- static long ioctl_create_file(struct file *file,
- struct incfs_new_file_args __user *usr_args)
- {
- struct mount_info *mi = get_mount_info(file_superblock(file));
- struct incfs_new_file_args args;
- char *file_id_str = NULL;
- struct dentry *index_file_dentry = NULL;
- struct dentry *named_file_dentry = NULL;
- struct dentry *incomplete_file_dentry = NULL;
- struct path parent_dir_path = {};
- struct inode *index_dir_inode = NULL;
- __le64 size_attr_value = 0;
- char *file_name = NULL;
- char *attr_value = NULL;
- int error = 0;
- bool locked = false;
- bool index_linked = false;
- bool name_linked = false;
- bool incomplete_linked = false;
- if (!mi || !mi->mi_index_dir || !mi->mi_incomplete_dir) {
- error = -EFAULT;
- goto out;
- }
- if (copy_from_user(&args, usr_args, sizeof(args)) > 0) {
- error = -EFAULT;
- goto out;
- }
- file_name = strndup_user(u64_to_user_ptr(args.file_name), PATH_MAX);
- if (IS_ERR(file_name)) {
- error = PTR_ERR(file_name);
- file_name = NULL;
- goto out;
- }
- error = validate_name(file_name);
- if (error)
- goto out;
- file_id_str = file_id_to_str(args.file_id);
- if (!file_id_str) {
- error = -ENOMEM;
- goto out;
- }
- error = mutex_lock_interruptible(&mi->mi_dir_struct_mutex);
- if (error)
- goto out;
- locked = true;
- /* Find a directory to put the file into. */
- error = dir_relative_path_resolve(mi,
- u64_to_user_ptr(args.directory_path),
- &parent_dir_path, NULL);
- if (error)
- goto out;
- if (parent_dir_path.dentry == mi->mi_index_dir) {
- /* Can't create a file directly inside .index */
- error = -EBUSY;
- goto out;
- }
- if (parent_dir_path.dentry == mi->mi_incomplete_dir) {
- /* Can't create a file directly inside .incomplete */
- error = -EBUSY;
- goto out;
- }
- /* Look up a dentry in the parent dir. It should be negative. */
- named_file_dentry = incfs_lookup_dentry(parent_dir_path.dentry,
- file_name);
- if (!named_file_dentry) {
- error = -EFAULT;
- goto out;
- }
- if (IS_ERR(named_file_dentry)) {
- error = PTR_ERR(named_file_dentry);
- named_file_dentry = NULL;
- goto out;
- }
- if (d_really_is_positive(named_file_dentry)) {
- /* File with this path already exists. */
- error = -EEXIST;
- goto out;
- }
- /* Look up a dentry in the incomplete dir. It should be negative. */
- incomplete_file_dentry = incfs_lookup_dentry(mi->mi_incomplete_dir,
- file_id_str);
- if (!incomplete_file_dentry) {
- error = -EFAULT;
- goto out;
- }
- if (IS_ERR(incomplete_file_dentry)) {
- error = PTR_ERR(incomplete_file_dentry);
- incomplete_file_dentry = NULL;
- goto out;
- }
- if (d_really_is_positive(incomplete_file_dentry)) {
- /* File with this path already exists. */
- error = -EEXIST;
- goto out;
- }
- /* Look up a dentry in the .index dir. It should be negative. */
- index_file_dentry = incfs_lookup_dentry(mi->mi_index_dir, file_id_str);
- if (!index_file_dentry) {
- error = -EFAULT;
- goto out;
- }
- if (IS_ERR(index_file_dentry)) {
- error = PTR_ERR(index_file_dentry);
- index_file_dentry = NULL;
- goto out;
- }
- if (d_really_is_positive(index_file_dentry)) {
- /* File with this ID already exists in index. */
- error = -EEXIST;
- goto out;
- }
- /* Creating a file in the .index dir. */
- index_dir_inode = d_inode(mi->mi_index_dir);
- inode_lock_nested(index_dir_inode, I_MUTEX_PARENT);
- error = vfs_create(index_dir_inode, index_file_dentry, args.mode | 0222,
- true);
- inode_unlock(index_dir_inode);
- if (error)
- goto out;
- if (!d_really_is_positive(index_file_dentry)) {
- error = -EINVAL;
- goto out;
- }
- error = chmod(index_file_dentry, args.mode | 0222);
- if (error) {
- pr_debug("incfs: chmod err: %d\n", error);
- goto out;
- }
- /* Save the file's ID as an xattr for easy fetching in future. */
- error = vfs_setxattr(index_file_dentry, INCFS_XATTR_ID_NAME,
- file_id_str, strlen(file_id_str), XATTR_CREATE);
- if (error) {
- pr_debug("incfs: vfs_setxattr err:%d\n", error);
- goto out;
- }
- /* Save the file's size as an xattr for easy fetching in future. */
- size_attr_value = cpu_to_le64(args.size);
- error = vfs_setxattr(index_file_dentry, INCFS_XATTR_SIZE_NAME,
- (char *)&size_attr_value, sizeof(size_attr_value),
- XATTR_CREATE);
- if (error) {
- pr_debug("incfs: vfs_setxattr err:%d\n", error);
- goto out;
- }
- /* Save the file's attribute as an xattr */
- if (args.file_attr_len && args.file_attr) {
- if (args.file_attr_len > INCFS_MAX_FILE_ATTR_SIZE) {
- error = -E2BIG;
- goto out;
- }
- attr_value = kmalloc(args.file_attr_len, GFP_NOFS);
- if (!attr_value) {
- error = -ENOMEM;
- goto out;
- }
- if (copy_from_user(attr_value,
- u64_to_user_ptr(args.file_attr),
- args.file_attr_len) > 0) {
- error = -EFAULT;
- goto out;
- }
- error = vfs_setxattr(index_file_dentry,
- INCFS_XATTR_METADATA_NAME,
- attr_value, args.file_attr_len,
- XATTR_CREATE);
- if (error)
- goto out;
- }
- /* Initializing a newly created file. */
- error = init_new_file(mi, index_file_dentry, &args.file_id, args.size,
- range(attr_value, args.file_attr_len),
- u64_to_user_ptr(args.signature_info),
- args.signature_size);
- if (error)
- goto out;
- index_linked = true;
- /* Linking a file with its real name from the requested dir. */
- error = incfs_link(index_file_dentry, named_file_dentry);
- if (error)
- goto out;
- name_linked = true;
- if (args.size) {
- /* Linking a file with its incomplete entry */
- error = incfs_link(index_file_dentry, incomplete_file_dentry);
- if (error)
- goto out;
- incomplete_linked = true;
- }
- notify_create(file, u64_to_user_ptr(args.directory_path), file_name,
- file_id_str, args.size != 0);
- out:
- if (error) {
- pr_debug("incfs: %s err:%d\n", __func__, error);
- if (index_linked)
- incfs_unlink(index_file_dentry);
- if (name_linked)
- incfs_unlink(named_file_dentry);
- if (incomplete_linked)
- incfs_unlink(incomplete_file_dentry);
- }
- kfree(file_id_str);
- kfree(file_name);
- kfree(attr_value);
- dput(named_file_dentry);
- dput(index_file_dentry);
- dput(incomplete_file_dentry);
- path_put(&parent_dir_path);
- if (locked)
- mutex_unlock(&mi->mi_dir_struct_mutex);
- return error;
- }
- static int init_new_mapped_file(struct mount_info *mi, struct dentry *dentry,
- incfs_uuid_t *uuid, u64 size, u64 offset)
- {
- struct path path = {};
- struct file *new_file;
- int error = 0;
- struct backing_file_context *bfc = NULL;
- if (!mi || !dentry || !uuid)
- return -EFAULT;
- /* Resize newly created file to its true size. */
- path = (struct path) {
- .mnt = mi->mi_backing_dir_path.mnt,
- .dentry = dentry
- };
- new_file = dentry_open(&path, O_RDWR | O_NOATIME | O_LARGEFILE,
- current_cred());
- if (IS_ERR(new_file)) {
- error = PTR_ERR(new_file);
- goto out;
- }
- bfc = incfs_alloc_bfc(mi, new_file);
- fput(new_file);
- if (IS_ERR(bfc)) {
- error = PTR_ERR(bfc);
- bfc = NULL;
- goto out;
- }
- mutex_lock(&bfc->bc_mutex);
- error = incfs_write_mapping_fh_to_backing_file(bfc, uuid, size, offset);
- if (error)
- goto out;
- out:
- if (bfc) {
- mutex_unlock(&bfc->bc_mutex);
- incfs_free_bfc(bfc);
- }
- if (error)
- pr_debug("incfs: %s error: %d\n", __func__, error);
- return error;
- }
- static long ioctl_create_mapped_file(struct file *file, void __user *arg)
- {
- struct mount_info *mi = get_mount_info(file_superblock(file));
- struct incfs_create_mapped_file_args __user *args_usr_ptr = arg;
- struct incfs_create_mapped_file_args args = {};
- char *file_name;
- int error = 0;
- struct path parent_dir_path = {};
- char *source_file_name = NULL;
- struct dentry *source_file_dentry = NULL;
- u64 source_file_size;
- struct dentry *file_dentry = NULL;
- struct inode *parent_inode;
- __le64 size_attr_value;
- if (copy_from_user(&args, args_usr_ptr, sizeof(args)) > 0)
- return -EINVAL;
- file_name = strndup_user(u64_to_user_ptr(args.file_name), PATH_MAX);
- if (IS_ERR(file_name)) {
- error = PTR_ERR(file_name);
- file_name = NULL;
- goto out;
- }
- error = validate_name(file_name);
- if (error)
- goto out;
- if (args.source_offset % INCFS_DATA_FILE_BLOCK_SIZE) {
- error = -EINVAL;
- goto out;
- }
- /* Validate file mapping is in range */
- source_file_name = file_id_to_str(args.source_file_id);
- if (!source_file_name) {
- pr_warn("Failed to alloc source_file_name\n");
- error = -ENOMEM;
- goto out;
- }
- source_file_dentry = incfs_lookup_dentry(mi->mi_index_dir,
- source_file_name);
- if (!source_file_dentry) {
- pr_warn("Source file does not exist\n");
- error = -EINVAL;
- goto out;
- }
- if (IS_ERR(source_file_dentry)) {
- pr_warn("Error opening source file\n");
- error = PTR_ERR(source_file_dentry);
- source_file_dentry = NULL;
- goto out;
- }
- if (!d_really_is_positive(source_file_dentry)) {
- pr_warn("Source file dentry negative\n");
- error = -EINVAL;
- goto out;
- }
- error = vfs_getxattr(source_file_dentry, INCFS_XATTR_SIZE_NAME,
- (char *)&size_attr_value, sizeof(size_attr_value));
- if (error < 0)
- goto out;
- if (error != sizeof(size_attr_value)) {
- pr_warn("Mapped file has no size attr\n");
- error = -EINVAL;
- goto out;
- }
- source_file_size = le64_to_cpu(size_attr_value);
- if (args.source_offset + args.size > source_file_size) {
- pr_warn("Mapped file out of range\n");
- error = -EINVAL;
- goto out;
- }
- /* Find a directory to put the file into. */
- error = dir_relative_path_resolve(mi,
- u64_to_user_ptr(args.directory_path),
- &parent_dir_path, NULL);
- if (error)
- goto out;
- if (parent_dir_path.dentry == mi->mi_index_dir) {
- /* Can't create a file directly inside .index */
- error = -EBUSY;
- goto out;
- }
- /* Look up a dentry in the parent dir. It should be negative. */
- file_dentry = incfs_lookup_dentry(parent_dir_path.dentry,
- file_name);
- if (!file_dentry) {
- error = -EFAULT;
- goto out;
- }
- if (IS_ERR(file_dentry)) {
- error = PTR_ERR(file_dentry);
- file_dentry = NULL;
- goto out;
- }
- if (d_really_is_positive(file_dentry)) {
- error = -EEXIST;
- goto out;
- }
- parent_inode = d_inode(parent_dir_path.dentry);
- inode_lock_nested(parent_inode, I_MUTEX_PARENT);
- error = vfs_create(parent_inode, file_dentry, args.mode | 0222, true);
- inode_unlock(parent_inode);
- if (error)
- goto out;
- error = chmod(file_dentry, args.mode | 0222);
- if (error) {
- pr_debug("incfs: chmod err: %d\n", error);
- goto delete_file;
- }
- /* Save the file's size as an xattr for easy fetching in future. */
- size_attr_value = cpu_to_le64(args.size);
- error = vfs_setxattr(file_dentry, INCFS_XATTR_SIZE_NAME,
- (char *)&size_attr_value, sizeof(size_attr_value),
- XATTR_CREATE);
- if (error) {
- pr_debug("incfs: vfs_setxattr err:%d\n", error);
- goto delete_file;
- }
- error = init_new_mapped_file(mi, file_dentry, &args.source_file_id,
- args.size, args.source_offset);
- if (error)
- goto delete_file;
- notify_create(file, u64_to_user_ptr(args.directory_path), file_name,
- NULL, false);
- goto out;
- delete_file:
- incfs_unlink(file_dentry);
- out:
- dput(file_dentry);
- dput(source_file_dentry);
- path_put(&parent_dir_path);
- kfree(file_name);
- kfree(source_file_name);
- return error;
- }
- static long ioctl_get_read_timeouts(struct mount_info *mi, void __user *arg)
- {
- struct incfs_get_read_timeouts_args __user *args_usr_ptr = arg;
- struct incfs_get_read_timeouts_args args = {};
- int error = 0;
- struct incfs_per_uid_read_timeouts *buffer;
- int size;
- if (copy_from_user(&args, args_usr_ptr, sizeof(args)))
- return -EINVAL;
- if (args.timeouts_array_size_out > INCFS_DATA_FILE_BLOCK_SIZE)
- return -EINVAL;
- buffer = kzalloc(args.timeouts_array_size_out, GFP_NOFS);
- if (!buffer)
- return -ENOMEM;
- spin_lock(&mi->mi_per_uid_read_timeouts_lock);
- size = mi->mi_per_uid_read_timeouts_size;
- if (args.timeouts_array_size < size)
- error = -E2BIG;
- else if (size)
- memcpy(buffer, mi->mi_per_uid_read_timeouts, size);
- spin_unlock(&mi->mi_per_uid_read_timeouts_lock);
- args.timeouts_array_size_out = size;
- if (!error && size)
- if (copy_to_user(u64_to_user_ptr(args.timeouts_array), buffer,
- size))
- error = -EFAULT;
- if (!error || error == -E2BIG)
- if (copy_to_user(args_usr_ptr, &args, sizeof(args)) > 0)
- error = -EFAULT;
- kfree(buffer);
- return error;
- }
- static long ioctl_set_read_timeouts(struct mount_info *mi, void __user *arg)
- {
- struct incfs_set_read_timeouts_args __user *args_usr_ptr = arg;
- struct incfs_set_read_timeouts_args args = {};
- int error = 0;
- int size;
- struct incfs_per_uid_read_timeouts *buffer = NULL, *tmp;
- int i;
- if (copy_from_user(&args, args_usr_ptr, sizeof(args)))
- return -EINVAL;
- size = args.timeouts_array_size;
- if (size) {
- if (size > INCFS_DATA_FILE_BLOCK_SIZE ||
- size % sizeof(*buffer) != 0)
- return -EINVAL;
- buffer = kzalloc(size, GFP_NOFS);
- if (!buffer)
- return -ENOMEM;
- if (copy_from_user(buffer, u64_to_user_ptr(args.timeouts_array),
- size)) {
- error = -EINVAL;
- goto out;
- }
- for (i = 0; i < size / sizeof(*buffer); ++i) {
- struct incfs_per_uid_read_timeouts *t = &buffer[i];
- if (t->min_pending_time_us > t->max_pending_time_us) {
- error = -EINVAL;
- goto out;
- }
- }
- }
- spin_lock(&mi->mi_per_uid_read_timeouts_lock);
- mi->mi_per_uid_read_timeouts_size = size;
- tmp = mi->mi_per_uid_read_timeouts;
- mi->mi_per_uid_read_timeouts = buffer;
- buffer = tmp;
- spin_unlock(&mi->mi_per_uid_read_timeouts_lock);
- out:
- kfree(buffer);
- return error;
- }
- static long ioctl_get_last_read_error(struct mount_info *mi, void __user *arg)
- {
- struct incfs_get_last_read_error_args __user *args_usr_ptr = arg;
- struct incfs_get_last_read_error_args args = {};
- int error;
- error = mutex_lock_interruptible(&mi->mi_le_mutex);
- if (error)
- return error;
- args.file_id_out = mi->mi_le_file_id;
- args.time_us_out = mi->mi_le_time_us;
- args.page_out = mi->mi_le_page;
- args.errno_out = mi->mi_le_errno;
- args.uid_out = mi->mi_le_uid;
- mutex_unlock(&mi->mi_le_mutex);
- if (copy_to_user(args_usr_ptr, &args, sizeof(args)) > 0)
- error = -EFAULT;
- return error;
- }
- static long pending_reads_dispatch_ioctl(struct file *f, unsigned int req,
- unsigned long arg)
- {
- struct mount_info *mi = get_mount_info(file_superblock(f));
- switch (req) {
- case INCFS_IOC_CREATE_FILE:
- return ioctl_create_file(f, (void __user *)arg);
- case INCFS_IOC_PERMIT_FILL:
- return ioctl_permit_fill(f, (void __user *)arg);
- case INCFS_IOC_CREATE_MAPPED_FILE:
- return ioctl_create_mapped_file(f, (void __user *)arg);
- case INCFS_IOC_GET_READ_TIMEOUTS:
- return ioctl_get_read_timeouts(mi, (void __user *)arg);
- case INCFS_IOC_SET_READ_TIMEOUTS:
- return ioctl_set_read_timeouts(mi, (void __user *)arg);
- case INCFS_IOC_GET_LAST_READ_ERROR:
- return ioctl_get_last_read_error(mi, (void __user *)arg);
- default:
- return -EINVAL;
- }
- }
- static const struct file_operations incfs_pending_reads_file_ops = {
- .read = pending_reads_read,
- .poll = pending_reads_poll,
- .open = pending_reads_open,
- .release = pending_reads_release,
- .llseek = noop_llseek,
- .unlocked_ioctl = pending_reads_dispatch_ioctl,
- .compat_ioctl = pending_reads_dispatch_ioctl
- };
- /*******************************************************************************
- * .log pseudo file definition
- ******************************************************************************/
- #define INCFS_LOG_INODE 3
- static const char log_file_name[] = INCFS_LOG_FILENAME;
- /* State of an open .log file, unique for each file descriptor. */
- struct log_file_state {
- struct read_log_state state;
- };
- static ssize_t log_read(struct file *f, char __user *buf, size_t len,
- loff_t *ppos)
- {
- struct log_file_state *log_state = f->private_data;
- struct mount_info *mi = get_mount_info(file_superblock(f));
- int total_reads_collected = 0;
- int rl_size;
- ssize_t result = 0;
- bool report_uid;
- unsigned long page = 0;
- struct incfs_pending_read_info *reads_buf = NULL;
- struct incfs_pending_read_info2 *reads_buf2 = NULL;
- size_t record_size;
- ssize_t reads_to_collect;
- ssize_t reads_per_page;
- if (!mi)
- return -EFAULT;
- report_uid = mi->mi_options.report_uid;
- record_size = report_uid ? sizeof(*reads_buf2) : sizeof(*reads_buf);
- reads_to_collect = len / record_size;
- reads_per_page = PAGE_SIZE / record_size;
- rl_size = READ_ONCE(mi->mi_log.rl_size);
- if (rl_size == 0)
- return 0;
- page = __get_free_page(GFP_NOFS);
- if (!page)
- return -ENOMEM;
- if (report_uid)
- reads_buf2 = (struct incfs_pending_read_info2 *)page;
- else
- reads_buf = (struct incfs_pending_read_info *)page;
- reads_to_collect = min_t(ssize_t, rl_size, reads_to_collect);
- while (reads_to_collect > 0) {
- struct read_log_state next_state;
- int reads_collected;
- memcpy(&next_state, &log_state->state, sizeof(next_state));
- reads_collected = incfs_collect_logged_reads(
- mi, &next_state, reads_buf, reads_buf2,
- min_t(ssize_t, reads_to_collect, reads_per_page));
- if (reads_collected <= 0) {
- result = total_reads_collected ?
- total_reads_collected * record_size :
- reads_collected;
- goto out;
- }
- if (copy_to_user(buf, (void *)page,
- reads_collected * record_size)) {
- result = total_reads_collected ?
- total_reads_collected * record_size :
- -EFAULT;
- goto out;
- }
- memcpy(&log_state->state, &next_state, sizeof(next_state));
- total_reads_collected += reads_collected;
- buf += reads_collected * record_size;
- reads_to_collect -= reads_collected;
- }
- result = total_reads_collected * record_size;
- *ppos = 0;
- out:
- free_page(page);
- return result;
- }
- static __poll_t log_poll(struct file *file, poll_table *wait)
- {
- struct log_file_state *log_state = file->private_data;
- struct mount_info *mi = get_mount_info(file_superblock(file));
- int count;
- __poll_t ret = 0;
- poll_wait(file, &mi->mi_log.ml_notif_wq, wait);
- count = incfs_get_uncollected_logs_count(mi, &log_state->state);
- if (count >= mi->mi_options.read_log_wakeup_count)
- ret = EPOLLIN | EPOLLRDNORM;
- return ret;
- }
- static int log_open(struct inode *inode, struct file *file)
- {
- struct log_file_state *log_state = NULL;
- struct mount_info *mi = get_mount_info(file_superblock(file));
- log_state = kzalloc(sizeof(*log_state), GFP_NOFS);
- if (!log_state)
- return -ENOMEM;
- log_state->state = incfs_get_log_state(mi);
- file->private_data = log_state;
- return 0;
- }
- static int log_release(struct inode *inode, struct file *file)
- {
- kfree(file->private_data);
- return 0;
- }
- static const struct file_operations incfs_log_file_ops = {
- .read = log_read,
- .poll = log_poll,
- .open = log_open,
- .release = log_release,
- .llseek = noop_llseek,
- };
- /*******************************************************************************
- * .blocks_written pseudo file definition
- ******************************************************************************/
- #define INCFS_BLOCKS_WRITTEN_INODE 4
- static const char blocks_written_file_name[] = INCFS_BLOCKS_WRITTEN_FILENAME;
- /* State of an open .blocks_written file, unique for each file descriptor. */
- struct blocks_written_file_state {
- unsigned long blocks_written;
- };
- static ssize_t blocks_written_read(struct file *f, char __user *buf, size_t len,
- loff_t *ppos)
- {
- struct mount_info *mi = get_mount_info(file_superblock(f));
- struct blocks_written_file_state *state = f->private_data;
- unsigned long blocks_written;
- char string[21];
- int result = 0;
- if (!mi)
- return -EFAULT;
- blocks_written = atomic_read(&mi->mi_blocks_written);
- if (state->blocks_written == blocks_written)
- return 0;
- result = snprintf(string, sizeof(string), "%lu", blocks_written);
- if (result > len)
- result = len;
- if (copy_to_user(buf, string, result))
- return -EFAULT;
- state->blocks_written = blocks_written;
- return result;
- }
- static __poll_t blocks_written_poll(struct file *f, poll_table *wait)
- {
- struct mount_info *mi = get_mount_info(file_superblock(f));
- struct blocks_written_file_state *state = f->private_data;
- unsigned long blocks_written;
- if (!mi)
- return 0;
- poll_wait(f, &mi->mi_blocks_written_notif_wq, wait);
- blocks_written = atomic_read(&mi->mi_blocks_written);
- if (state->blocks_written == blocks_written)
- return 0;
- return EPOLLIN | EPOLLRDNORM;
- }
- static int blocks_written_open(struct inode *inode, struct file *file)
- {
- struct blocks_written_file_state *state =
- kzalloc(sizeof(*state), GFP_NOFS);
- if (!state)
- return -ENOMEM;
- state->blocks_written = -1;
- file->private_data = state;
- return 0;
- }
- static int blocks_written_release(struct inode *inode, struct file *file)
- {
- kfree(file->private_data);
- return 0;
- }
- static const struct file_operations incfs_blocks_written_file_ops = {
- .read = blocks_written_read,
- .poll = blocks_written_poll,
- .open = blocks_written_open,
- .release = blocks_written_release,
- .llseek = noop_llseek,
- };
- /*******************************************************************************
- * Generic inode lookup functionality
- ******************************************************************************/
- const struct mem_range incfs_pseudo_file_names[] = {
- { .data = (u8 *)pending_reads_file_name,
- .len = ARRAY_SIZE(pending_reads_file_name) - 1 },
- { .data = (u8 *)log_file_name, .len = ARRAY_SIZE(log_file_name) - 1 },
- { .data = (u8 *)blocks_written_file_name,
- .len = ARRAY_SIZE(blocks_written_file_name) - 1 }
- };
- const unsigned long incfs_pseudo_file_inodes[] = { INCFS_PENDING_READS_INODE,
- INCFS_LOG_INODE,
- INCFS_BLOCKS_WRITTEN_INODE };
- static const struct file_operations *const pseudo_file_operations[] = {
- &incfs_pending_reads_file_ops, &incfs_log_file_ops,
- &incfs_blocks_written_file_ops
- };
- static bool is_pseudo_filename(struct mem_range name)
- {
- int i = 0;
- for (; i < ARRAY_SIZE(incfs_pseudo_file_names); ++i)
- if (incfs_equal_ranges(incfs_pseudo_file_names[i], name))
- return true;
- return false;
- }
- static bool get_pseudo_inode(int ino, struct inode *inode)
- {
- int i = 0;
- for (; i < ARRAY_SIZE(incfs_pseudo_file_inodes); ++i)
- if (ino == incfs_pseudo_file_inodes[i])
- break;
- if (i == ARRAY_SIZE(incfs_pseudo_file_inodes))
- return false;
- inode->i_ctime = (struct timespec64){};
- inode->i_mtime = inode->i_ctime;
- inode->i_atime = inode->i_ctime;
- inode->i_size = 0;
- inode->i_ino = ino;
- inode->i_private = NULL;
- inode_init_owner(inode, NULL, S_IFREG | READ_WRITE_FILE_MODE);
- inode->i_op = &incfs_file_inode_ops;
- inode->i_fop = pseudo_file_operations[i];
- return true;
- }
- struct inode_search {
- unsigned long ino;
- };
- static int inode_test(struct inode *inode, void *opaque)
- {
- struct inode_search *search = opaque;
- return inode->i_ino == search->ino;
- }
- static int inode_set(struct inode *inode, void *opaque)
- {
- struct inode_search *search = opaque;
- if (get_pseudo_inode(search->ino, inode))
- return 0;
- /* Unknown inode requested. */
- return -EINVAL;
- }
- static struct inode *fetch_inode(struct super_block *sb, unsigned long ino)
- {
- struct inode_search search = {
- .ino = ino
- };
- struct inode *inode = iget5_locked(sb, search.ino, inode_test,
- inode_set, &search);
- if (!inode)
- return ERR_PTR(-ENOMEM);
- if (inode->i_state & I_NEW)
- unlock_new_inode(inode);
- return inode;
- }
- int dir_lookup_pseudo_files(struct super_block *sb, struct dentry *dentry)
- {
- struct mem_range name_range =
- range((u8 *)dentry->d_name.name, dentry->d_name.len);
- unsigned long ino;
- struct inode *inode;
- int i = 0;
- for (; i < ARRAY_SIZE(incfs_pseudo_file_names); ++i)
- if (incfs_equal_ranges(incfs_pseudo_file_names[i], name_range))
- break;
- if (i == ARRAY_SIZE(incfs_pseudo_file_names))
- return -ENOENT;
- ino = incfs_pseudo_file_inodes[i];
- inode = fetch_inode(sb, ino);
- if (IS_ERR(inode))
- return PTR_ERR(inode);
- d_add(dentry, inode);
- return 0;
- }
- int emit_pseudo_files(struct dir_context *ctx)
- {
- loff_t i = ctx->pos;
- for (; i < ARRAY_SIZE(incfs_pseudo_file_names); ++i) {
- if (!dir_emit(ctx, incfs_pseudo_file_names[i].data,
- incfs_pseudo_file_names[i].len,
- incfs_pseudo_file_inodes[i], DT_REG))
- return -EINVAL;
- ctx->pos++;
- }
- return 0;
- }
|