mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-20 09:31:09 +00:00
af579beb66
Introduce a new flag FAN_REPORT_PIDFD for fanotify_init(2) which allows userspace applications to control whether a pidfd information record containing a pidfd is to be returned alongside the generic event metadata for each event. If FAN_REPORT_PIDFD is enabled for a notification group, an additional struct fanotify_event_info_pidfd object type will be supplied alongside the generic struct fanotify_event_metadata for a single event. This functionality is analogous to that of FAN_REPORT_FID in terms of how the event structure is supplied to a userspace application. Usage of FAN_REPORT_PIDFD with FAN_REPORT_FID/FAN_REPORT_DFID_NAME is permitted, and in this case a struct fanotify_event_info_pidfd object will likely follow any struct fanotify_event_info_fid object. Currently, the usage of the FAN_REPORT_TID flag is not permitted along with FAN_REPORT_PIDFD as the pidfd API currently only supports the creation of pidfds for thread-group leaders. Additionally, usage of the FAN_REPORT_PIDFD flag is limited to privileged processes only i.e. event listeners that are running with the CAP_SYS_ADMIN capability. Attempting to supply the FAN_REPORT_TID initialization flags with FAN_REPORT_PIDFD or creating a notification group without CAP_SYS_ADMIN will result with -EINVAL being returned to the caller. In the event of a pidfd creation error, there are two types of error values that can be reported back to the listener. There is FAN_NOPIDFD, which will be reported in cases where the process responsible for generating the event has terminated prior to the event listener being able to read the event. Then there is FAN_EPIDFD, which will be reported when a more generic pidfd creation error has occurred when fanotify calls pidfd_create(). Link: https://lore.kernel.org/r/5f9e09cff7ed62bfaa51c1369e0f7ea5f16a91aa.1628398044.git.repnop@google.com Signed-off-by: Matthew Bobrowski <repnop@google.com> Signed-off-by: Jan Kara <jack@suse.cz>
118 lines
3.8 KiB
C
118 lines
3.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _LINUX_FANOTIFY_H
|
|
#define _LINUX_FANOTIFY_H
|
|
|
|
#include <linux/sysctl.h>
|
|
#include <uapi/linux/fanotify.h>
|
|
|
|
extern struct ctl_table fanotify_table[]; /* for sysctl */
|
|
|
|
#define FAN_GROUP_FLAG(group, flag) \
|
|
((group)->fanotify_data.flags & (flag))
|
|
|
|
/*
|
|
* Flags allowed to be passed from/to userspace.
|
|
*
|
|
* We intentionally do not add new bits to the old FAN_ALL_* constants, because
|
|
* they are uapi exposed constants. If there are programs out there using
|
|
* these constant, the programs may break if re-compiled with new uapi headers
|
|
* and then run on an old kernel.
|
|
*/
|
|
|
|
/* Group classes where permission events are allowed */
|
|
#define FANOTIFY_PERM_CLASSES (FAN_CLASS_CONTENT | \
|
|
FAN_CLASS_PRE_CONTENT)
|
|
|
|
#define FANOTIFY_CLASS_BITS (FAN_CLASS_NOTIF | FANOTIFY_PERM_CLASSES)
|
|
|
|
#define FANOTIFY_FID_BITS (FAN_REPORT_FID | FAN_REPORT_DFID_NAME)
|
|
|
|
#define FANOTIFY_INFO_MODES (FANOTIFY_FID_BITS | FAN_REPORT_PIDFD)
|
|
|
|
/*
|
|
* fanotify_init() flags that require CAP_SYS_ADMIN.
|
|
* We do not allow unprivileged groups to request permission events.
|
|
* We do not allow unprivileged groups to get other process pid in events.
|
|
* We do not allow unprivileged groups to use unlimited resources.
|
|
*/
|
|
#define FANOTIFY_ADMIN_INIT_FLAGS (FANOTIFY_PERM_CLASSES | \
|
|
FAN_REPORT_TID | \
|
|
FAN_REPORT_PIDFD | \
|
|
FAN_UNLIMITED_QUEUE | \
|
|
FAN_UNLIMITED_MARKS)
|
|
|
|
/*
|
|
* fanotify_init() flags that are allowed for user without CAP_SYS_ADMIN.
|
|
* FAN_CLASS_NOTIF is the only class we allow for unprivileged group.
|
|
* We do not allow unprivileged groups to get file descriptors in events,
|
|
* so one of the flags for reporting file handles is required.
|
|
*/
|
|
#define FANOTIFY_USER_INIT_FLAGS (FAN_CLASS_NOTIF | \
|
|
FANOTIFY_FID_BITS | \
|
|
FAN_CLOEXEC | FAN_NONBLOCK)
|
|
|
|
#define FANOTIFY_INIT_FLAGS (FANOTIFY_ADMIN_INIT_FLAGS | \
|
|
FANOTIFY_USER_INIT_FLAGS)
|
|
|
|
/* Internal group flags */
|
|
#define FANOTIFY_UNPRIV 0x80000000
|
|
#define FANOTIFY_INTERNAL_GROUP_FLAGS (FANOTIFY_UNPRIV)
|
|
|
|
#define FANOTIFY_MARK_TYPE_BITS (FAN_MARK_INODE | FAN_MARK_MOUNT | \
|
|
FAN_MARK_FILESYSTEM)
|
|
|
|
#define FANOTIFY_MARK_FLAGS (FANOTIFY_MARK_TYPE_BITS | \
|
|
FAN_MARK_ADD | \
|
|
FAN_MARK_REMOVE | \
|
|
FAN_MARK_DONT_FOLLOW | \
|
|
FAN_MARK_ONLYDIR | \
|
|
FAN_MARK_IGNORED_MASK | \
|
|
FAN_MARK_IGNORED_SURV_MODIFY | \
|
|
FAN_MARK_FLUSH)
|
|
|
|
/*
|
|
* Events that can be reported with data type FSNOTIFY_EVENT_PATH.
|
|
* Note that FAN_MODIFY can also be reported with data type
|
|
* FSNOTIFY_EVENT_INODE.
|
|
*/
|
|
#define FANOTIFY_PATH_EVENTS (FAN_ACCESS | FAN_MODIFY | \
|
|
FAN_CLOSE | FAN_OPEN | FAN_OPEN_EXEC)
|
|
|
|
/*
|
|
* Directory entry modification events - reported only to directory
|
|
* where entry is modified and not to a watching parent.
|
|
*/
|
|
#define FANOTIFY_DIRENT_EVENTS (FAN_MOVE | FAN_CREATE | FAN_DELETE)
|
|
|
|
/* Events that can only be reported with data type FSNOTIFY_EVENT_INODE */
|
|
#define FANOTIFY_INODE_EVENTS (FANOTIFY_DIRENT_EVENTS | \
|
|
FAN_ATTRIB | FAN_MOVE_SELF | FAN_DELETE_SELF)
|
|
|
|
/* Events that user can request to be notified on */
|
|
#define FANOTIFY_EVENTS (FANOTIFY_PATH_EVENTS | \
|
|
FANOTIFY_INODE_EVENTS)
|
|
|
|
/* Events that require a permission response from user */
|
|
#define FANOTIFY_PERM_EVENTS (FAN_OPEN_PERM | FAN_ACCESS_PERM | \
|
|
FAN_OPEN_EXEC_PERM)
|
|
|
|
/* Extra flags that may be reported with event or control handling of events */
|
|
#define FANOTIFY_EVENT_FLAGS (FAN_EVENT_ON_CHILD | FAN_ONDIR)
|
|
|
|
/* Events that may be reported to user */
|
|
#define FANOTIFY_OUTGOING_EVENTS (FANOTIFY_EVENTS | \
|
|
FANOTIFY_PERM_EVENTS | \
|
|
FAN_Q_OVERFLOW | FAN_ONDIR)
|
|
|
|
#define ALL_FANOTIFY_EVENT_BITS (FANOTIFY_OUTGOING_EVENTS | \
|
|
FANOTIFY_EVENT_FLAGS)
|
|
|
|
/* Do not use these old uapi constants internally */
|
|
#undef FAN_ALL_CLASS_BITS
|
|
#undef FAN_ALL_INIT_FLAGS
|
|
#undef FAN_ALL_MARK_FLAGS
|
|
#undef FAN_ALL_EVENTS
|
|
#undef FAN_ALL_PERM_EVENTS
|
|
#undef FAN_ALL_OUTGOING_EVENTS
|
|
|
|
#endif /* _LINUX_FANOTIFY_H */
|