kernel_optimize_test/include/linux/sysfs.h
Joe Perches 2efc459d06 sysfs: Add sysfs_emit and sysfs_emit_at to format sysfs output
Output defects can exist in sysfs content using sprintf and snprintf.

sprintf does not know the PAGE_SIZE maximum of the temporary buffer
used for outputting sysfs content and it's possible to overrun the
PAGE_SIZE buffer length.

Add a generic sysfs_emit function that knows that the size of the
temporary buffer and ensures that no overrun is done.

Add a generic sysfs_emit_at function that can be used in multiple
call situations that also ensures that no overrun is done.

Validate the output buffer argument to be page aligned.
Validate the offset len argument to be within the PAGE_SIZE buf.

Signed-off-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/884235202216d464d61ee975f7465332c86f76b2.1600285923.git.joe@perches.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-02 12:02:30 +02:00

637 lines
17 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* sysfs.h - definitions for the device driver filesystem
*
* Copyright (c) 2001,2002 Patrick Mochel
* Copyright (c) 2004 Silicon Graphics, Inc.
* Copyright (c) 2007 SUSE Linux Products GmbH
* Copyright (c) 2007 Tejun Heo <teheo@suse.de>
*
* Please see Documentation/filesystems/sysfs.rst for more information.
*/
#ifndef _SYSFS_H_
#define _SYSFS_H_
#include <linux/kernfs.h>
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/kobject_ns.h>
#include <linux/stat.h>
#include <linux/atomic.h>
struct kobject;
struct module;
struct bin_attribute;
enum kobj_ns_type;
struct attribute {
const char *name;
umode_t mode;
#ifdef CONFIG_DEBUG_LOCK_ALLOC
bool ignore_lockdep:1;
struct lock_class_key *key;
struct lock_class_key skey;
#endif
};
/**
* sysfs_attr_init - initialize a dynamically allocated sysfs attribute
* @attr: struct attribute to initialize
*
* Initialize a dynamically allocated struct attribute so we can
* make lockdep happy. This is a new requirement for attributes
* and initially this is only needed when lockdep is enabled.
* Lockdep gives a nice error when your attribute is added to
* sysfs if you don't have this.
*/
#ifdef CONFIG_DEBUG_LOCK_ALLOC
#define sysfs_attr_init(attr) \
do { \
static struct lock_class_key __key; \
\
(attr)->key = &__key; \
} while (0)
#else
#define sysfs_attr_init(attr) do {} while (0)
#endif
/**
* struct attribute_group - data structure used to declare an attribute group.
* @name: Optional: Attribute group name
* If specified, the attribute group will be created in
* a new subdirectory with this name.
* @is_visible: Optional: Function to return permissions associated with an
* attribute of the group. Will be called repeatedly for each
* non-binary attribute in the group. Only read/write
* permissions as well as SYSFS_PREALLOC are accepted. Must
* return 0 if an attribute is not visible. The returned value
* will replace static permissions defined in struct attribute.
* @is_bin_visible:
* Optional: Function to return permissions associated with a
* binary attribute of the group. Will be called repeatedly
* for each binary attribute in the group. Only read/write
* permissions as well as SYSFS_PREALLOC are accepted. Must
* return 0 if a binary attribute is not visible. The returned
* value will replace static permissions defined in
* struct bin_attribute.
* @attrs: Pointer to NULL terminated list of attributes.
* @bin_attrs: Pointer to NULL terminated list of binary attributes.
* Either attrs or bin_attrs or both must be provided.
*/
struct attribute_group {
const char *name;
umode_t (*is_visible)(struct kobject *,
struct attribute *, int);
umode_t (*is_bin_visible)(struct kobject *,
struct bin_attribute *, int);
struct attribute **attrs;
struct bin_attribute **bin_attrs;
};
/*
* Use these macros to make defining attributes easier.
* See include/linux/device.h for examples..
*/
#define SYSFS_PREALLOC 010000
#define __ATTR(_name, _mode, _show, _store) { \
.attr = {.name = __stringify(_name), \
.mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \
.show = _show, \
.store = _store, \
}
#define __ATTR_PREALLOC(_name, _mode, _show, _store) { \
.attr = {.name = __stringify(_name), \
.mode = SYSFS_PREALLOC | VERIFY_OCTAL_PERMISSIONS(_mode) },\
.show = _show, \
.store = _store, \
}
#define __ATTR_RO(_name) { \
.attr = { .name = __stringify(_name), .mode = 0444 }, \
.show = _name##_show, \
}
#define __ATTR_RO_MODE(_name, _mode) { \
.attr = { .name = __stringify(_name), \
.mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \
.show = _name##_show, \
}
#define __ATTR_RW_MODE(_name, _mode) { \
.attr = { .name = __stringify(_name), \
.mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \
.show = _name##_show, \
.store = _name##_store, \
}
#define __ATTR_WO(_name) { \
.attr = { .name = __stringify(_name), .mode = 0200 }, \
.store = _name##_store, \
}
#define __ATTR_RW(_name) __ATTR(_name, 0644, _name##_show, _name##_store)
#define __ATTR_NULL { .attr = { .name = NULL } }
#ifdef CONFIG_DEBUG_LOCK_ALLOC
#define __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) { \
.attr = {.name = __stringify(_name), .mode = _mode, \
.ignore_lockdep = true }, \
.show = _show, \
.store = _store, \
}
#else
#define __ATTR_IGNORE_LOCKDEP __ATTR
#endif
#define __ATTRIBUTE_GROUPS(_name) \
static const struct attribute_group *_name##_groups[] = { \
&_name##_group, \
NULL, \
}
#define ATTRIBUTE_GROUPS(_name) \
static const struct attribute_group _name##_group = { \
.attrs = _name##_attrs, \
}; \
__ATTRIBUTE_GROUPS(_name)
struct file;
struct vm_area_struct;
struct bin_attribute {
struct attribute attr;
size_t size;
void *private;
ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
char *, loff_t, size_t);
ssize_t (*write)(struct file *, struct kobject *, struct bin_attribute *,
char *, loff_t, size_t);
int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
struct vm_area_struct *vma);
};
/**
* sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
* @attr: struct bin_attribute to initialize
*
* Initialize a dynamically allocated struct bin_attribute so we
* can make lockdep happy. This is a new requirement for
* attributes and initially this is only needed when lockdep is
* enabled. Lockdep gives a nice error when your attribute is
* added to sysfs if you don't have this.
*/
#define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
/* macros to create static binary attributes easier */
#define __BIN_ATTR(_name, _mode, _read, _write, _size) { \
.attr = { .name = __stringify(_name), .mode = _mode }, \
.read = _read, \
.write = _write, \
.size = _size, \
}
#define __BIN_ATTR_RO(_name, _size) { \
.attr = { .name = __stringify(_name), .mode = 0444 }, \
.read = _name##_read, \
.size = _size, \
}
#define __BIN_ATTR_WO(_name, _size) { \
.attr = { .name = __stringify(_name), .mode = 0200 }, \
.write = _name##_write, \
.size = _size, \
}
#define __BIN_ATTR_RW(_name, _size) \
__BIN_ATTR(_name, 0644, _name##_read, _name##_write, _size)
#define __BIN_ATTR_NULL __ATTR_NULL
#define BIN_ATTR(_name, _mode, _read, _write, _size) \
struct bin_attribute bin_attr_##_name = __BIN_ATTR(_name, _mode, _read, \
_write, _size)
#define BIN_ATTR_RO(_name, _size) \
struct bin_attribute bin_attr_##_name = __BIN_ATTR_RO(_name, _size)
#define BIN_ATTR_WO(_name, _size) \
struct bin_attribute bin_attr_##_name = __BIN_ATTR_WO(_name, _size)
#define BIN_ATTR_RW(_name, _size) \
struct bin_attribute bin_attr_##_name = __BIN_ATTR_RW(_name, _size)
struct sysfs_ops {
ssize_t (*show)(struct kobject *, struct attribute *, char *);
ssize_t (*store)(struct kobject *, struct attribute *, const char *, size_t);
};
#ifdef CONFIG_SYSFS
int __must_check sysfs_create_dir_ns(struct kobject *kobj, const void *ns);
void sysfs_remove_dir(struct kobject *kobj);
int __must_check sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name,
const void *new_ns);
int __must_check sysfs_move_dir_ns(struct kobject *kobj,
struct kobject *new_parent_kobj,
const void *new_ns);
int __must_check sysfs_create_mount_point(struct kobject *parent_kobj,
const char *name);
void sysfs_remove_mount_point(struct kobject *parent_kobj,
const char *name);
int __must_check sysfs_create_file_ns(struct kobject *kobj,
const struct attribute *attr,
const void *ns);
int __must_check sysfs_create_files(struct kobject *kobj,
const struct attribute * const *attr);
int __must_check sysfs_chmod_file(struct kobject *kobj,
const struct attribute *attr, umode_t mode);
struct kernfs_node *sysfs_break_active_protection(struct kobject *kobj,
const struct attribute *attr);
void sysfs_unbreak_active_protection(struct kernfs_node *kn);
void sysfs_remove_file_ns(struct kobject *kobj, const struct attribute *attr,
const void *ns);
bool sysfs_remove_file_self(struct kobject *kobj, const struct attribute *attr);
void sysfs_remove_files(struct kobject *kobj, const struct attribute * const *attr);
int __must_check sysfs_create_bin_file(struct kobject *kobj,
const struct bin_attribute *attr);
void sysfs_remove_bin_file(struct kobject *kobj,
const struct bin_attribute *attr);
int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
const char *name);
int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
struct kobject *target,
const char *name);
void sysfs_remove_link(struct kobject *kobj, const char *name);
int sysfs_rename_link_ns(struct kobject *kobj, struct kobject *target,
const char *old_name, const char *new_name,
const void *new_ns);
void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
const char *name);
int __must_check sysfs_create_group(struct kobject *kobj,
const struct attribute_group *grp);
int __must_check sysfs_create_groups(struct kobject *kobj,
const struct attribute_group **groups);
int __must_check sysfs_update_groups(struct kobject *kobj,
const struct attribute_group **groups);
int sysfs_update_group(struct kobject *kobj,
const struct attribute_group *grp);
void sysfs_remove_group(struct kobject *kobj,
const struct attribute_group *grp);
void sysfs_remove_groups(struct kobject *kobj,
const struct attribute_group **groups);
int sysfs_add_file_to_group(struct kobject *kobj,
const struct attribute *attr, const char *group);
void sysfs_remove_file_from_group(struct kobject *kobj,
const struct attribute *attr, const char *group);
int sysfs_merge_group(struct kobject *kobj,
const struct attribute_group *grp);
void sysfs_unmerge_group(struct kobject *kobj,
const struct attribute_group *grp);
int sysfs_add_link_to_group(struct kobject *kobj, const char *group_name,
struct kobject *target, const char *link_name);
void sysfs_remove_link_from_group(struct kobject *kobj, const char *group_name,
const char *link_name);
int compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
struct kobject *target_kobj,
const char *target_name,
const char *symlink_name);
void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
int __must_check sysfs_init(void);
static inline void sysfs_enable_ns(struct kernfs_node *kn)
{
return kernfs_enable_ns(kn);
}
int sysfs_file_change_owner(struct kobject *kobj, const char *name, kuid_t kuid,
kgid_t kgid);
int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid);
int sysfs_link_change_owner(struct kobject *kobj, struct kobject *targ,
const char *name, kuid_t kuid, kgid_t kgid);
int sysfs_groups_change_owner(struct kobject *kobj,
const struct attribute_group **groups,
kuid_t kuid, kgid_t kgid);
int sysfs_group_change_owner(struct kobject *kobj,
const struct attribute_group *groups, kuid_t kuid,
kgid_t kgid);
__printf(2, 3)
int sysfs_emit(char *buf, const char *fmt, ...);
__printf(3, 4)
int sysfs_emit_at(char *buf, int at, const char *fmt, ...);
#else /* CONFIG_SYSFS */
static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
{
return 0;
}
static inline void sysfs_remove_dir(struct kobject *kobj)
{
}
static inline int sysfs_rename_dir_ns(struct kobject *kobj,
const char *new_name, const void *new_ns)
{
return 0;
}
static inline int sysfs_move_dir_ns(struct kobject *kobj,
struct kobject *new_parent_kobj,
const void *new_ns)
{
return 0;
}
static inline int sysfs_create_mount_point(struct kobject *parent_kobj,
const char *name)
{
return 0;
}
static inline void sysfs_remove_mount_point(struct kobject *parent_kobj,
const char *name)
{
}
static inline int sysfs_create_file_ns(struct kobject *kobj,
const struct attribute *attr,
const void *ns)
{
return 0;
}
static inline int sysfs_create_files(struct kobject *kobj,
const struct attribute * const *attr)
{
return 0;
}
static inline int sysfs_chmod_file(struct kobject *kobj,
const struct attribute *attr, umode_t mode)
{
return 0;
}
static inline struct kernfs_node *
sysfs_break_active_protection(struct kobject *kobj,
const struct attribute *attr)
{
return NULL;
}
static inline void sysfs_unbreak_active_protection(struct kernfs_node *kn)
{
}
static inline void sysfs_remove_file_ns(struct kobject *kobj,
const struct attribute *attr,
const void *ns)
{
}
static inline bool sysfs_remove_file_self(struct kobject *kobj,
const struct attribute *attr)
{
return false;
}
static inline void sysfs_remove_files(struct kobject *kobj,
const struct attribute * const *attr)
{
}
static inline int sysfs_create_bin_file(struct kobject *kobj,
const struct bin_attribute *attr)
{
return 0;
}
static inline void sysfs_remove_bin_file(struct kobject *kobj,
const struct bin_attribute *attr)
{
}
static inline int sysfs_create_link(struct kobject *kobj,
struct kobject *target, const char *name)
{
return 0;
}
static inline int sysfs_create_link_nowarn(struct kobject *kobj,
struct kobject *target,
const char *name)
{
return 0;
}
static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
{
}
static inline int sysfs_rename_link_ns(struct kobject *k, struct kobject *t,
const char *old_name,
const char *new_name, const void *ns)
{
return 0;
}
static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
const char *name)
{
}
static inline int sysfs_create_group(struct kobject *kobj,
const struct attribute_group *grp)
{
return 0;
}
static inline int sysfs_create_groups(struct kobject *kobj,
const struct attribute_group **groups)
{
return 0;
}
static inline int sysfs_update_groups(struct kobject *kobj,
const struct attribute_group **groups)
{
return 0;
}
static inline int sysfs_update_group(struct kobject *kobj,
const struct attribute_group *grp)
{
return 0;
}
static inline void sysfs_remove_group(struct kobject *kobj,
const struct attribute_group *grp)
{
}
static inline void sysfs_remove_groups(struct kobject *kobj,
const struct attribute_group **groups)
{
}
static inline int sysfs_add_file_to_group(struct kobject *kobj,
const struct attribute *attr, const char *group)
{
return 0;
}
static inline void sysfs_remove_file_from_group(struct kobject *kobj,
const struct attribute *attr, const char *group)
{
}
static inline int sysfs_merge_group(struct kobject *kobj,
const struct attribute_group *grp)
{
return 0;
}
static inline void sysfs_unmerge_group(struct kobject *kobj,
const struct attribute_group *grp)
{
}
static inline int sysfs_add_link_to_group(struct kobject *kobj,
const char *group_name, struct kobject *target,
const char *link_name)
{
return 0;
}
static inline void sysfs_remove_link_from_group(struct kobject *kobj,
const char *group_name, const char *link_name)
{
}
static inline int compat_only_sysfs_link_entry_to_kobj(struct kobject *kobj,
struct kobject *target_kobj,
const char *target_name,
const char *symlink_name)
{
return 0;
}
static inline void sysfs_notify(struct kobject *kobj, const char *dir,
const char *attr)
{
}
static inline int __must_check sysfs_init(void)
{
return 0;
}
static inline void sysfs_enable_ns(struct kernfs_node *kn)
{
}
static inline int sysfs_file_change_owner(struct kobject *kobj,
const char *name, kuid_t kuid,
kgid_t kgid)
{
return 0;
}
static inline int sysfs_link_change_owner(struct kobject *kobj,
struct kobject *targ,
const char *name, kuid_t kuid,
kgid_t kgid)
{
return 0;
}
static inline int sysfs_change_owner(struct kobject *kobj, kuid_t kuid, kgid_t kgid)
{
return 0;
}
static inline int sysfs_groups_change_owner(struct kobject *kobj,
const struct attribute_group **groups,
kuid_t kuid, kgid_t kgid)
{
return 0;
}
static inline int sysfs_group_change_owner(struct kobject *kobj,
const struct attribute_group *groups,
kuid_t kuid, kgid_t kgid)
{
return 0;
}
__printf(2, 3)
static inline int sysfs_emit(char *buf, const char *fmt, ...)
{
return 0;
}
__printf(3, 4)
static inline int sysfs_emit_at(char *buf, int at, const char *fmt, ...)
{
return 0;
}
#endif /* CONFIG_SYSFS */
static inline int __must_check sysfs_create_file(struct kobject *kobj,
const struct attribute *attr)
{
return sysfs_create_file_ns(kobj, attr, NULL);
}
static inline void sysfs_remove_file(struct kobject *kobj,
const struct attribute *attr)
{
sysfs_remove_file_ns(kobj, attr, NULL);
}
static inline int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
const char *old_name, const char *new_name)
{
return sysfs_rename_link_ns(kobj, target, old_name, new_name, NULL);
}
static inline void sysfs_notify_dirent(struct kernfs_node *kn)
{
kernfs_notify(kn);
}
static inline struct kernfs_node *sysfs_get_dirent(struct kernfs_node *parent,
const char *name)
{
return kernfs_find_and_get(parent, name);
}
static inline struct kernfs_node *sysfs_get(struct kernfs_node *kn)
{
kernfs_get(kn);
return kn;
}
static inline void sysfs_put(struct kernfs_node *kn)
{
kernfs_put(kn);
}
#endif /* _SYSFS_H_ */