Commit Graph

18 Commits

Author SHA1 Message Date
Andreas Gruenbacher f3640192c0 fanotify: split fanotify_remove_mark
split fanotify_remove_mark into fanotify_remove_inode_mark and
fanotify_remove_vfsmount_mark.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:59 -04:00
Andreas Gruenbacher eac8e9e80c fanotify: rename FAN_MARK_ON_VFSMOUNT to FAN_MARK_MOUNT
the term 'vfsmount' isn't sensicle to userspace.  instead call is 'mount.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:59 -04:00
Eric Paris 0ff21db9fc fanotify: hooks the fanotify_mark syscall to the vfsmount code
Create a new fanotify_mark flag which indicates we should attach the mark
to the vfsmount holding the object referenced by dfd and pathname rather
than the inode itself.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:59 -04:00
Andreas Gruenbacher 90dd201d1a fanotify: remove fanotify_add_mark
fanotify_add_mark now does nothing useful anymore, drop it.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:58 -04:00
Andreas Gruenbacher 52202dfbd9 fanotify: do not return pointer from fanotify_add_*_mark
No need to return the mark from fanotify_add_*_mark to fanotify_add_mark

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:58 -04:00
Andreas Gruenbacher 912ee3946c fanotify: do not call fanotify_update_object_mask in fanotify_add_mark
Recalculate masks in fanotify_add_mark, don't use
fanotify_update_object_mask.  This gets us one step closers to readable
code.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:58 -04:00
Andreas Gruenbacher 088b09b0ac fanotify: do not call fanotify_update_object_mask in fanotify_remove_mark
Recalculate masks in fanotify_remove_mark, don't use
fanotify_update_object_mask.  This gets us one step closers to readable
code.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:58 -04:00
Andreas Gruenbacher c6223f4649 fanotify: remove fanotify_update_mark
fanotify_update_mark() doesn't do much useful;  remove it.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:58 -04:00
Eric Paris 88826276dc fanotify: infrastructure to add an remove marks on vfsmounts
infrastructure work to add and remove marks on vfsmounts.  This should get
every set up except wiring the functions to the syscalls.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:57 -04:00
Eric Paris 5444e2981c fsnotify: split generic and inode specific mark code
currently all marking is done by functions in inode-mark.c.  Some of this
is pretty generic and should be instead done in a generic function and we
should only put the inode specific code in inode-mark.c

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:57 -04:00
Andreas Gruenbacher 32c3263221 fanotify: Add pids to events
Pass the process identifiers of the triggering processes to fanotify
listeners: this information is useful for event filtering and logging.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:56 -04:00
Andreas Gruenbacher 22aa425dec fanotify: create_fd cleanup
Code cleanup which does the fd creation work seperately from the userspace
metadata creation.  It fits better with the other code.

Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:56 -04:00
Heiko Carstens 9bbfc964b8 fanotify: CONFIG_HAVE_SYSCALL_WRAPPERS for sys_fanotify_mark
Please note that you need the patch below in addition, otherwise the
syscall wrapper stuff won't work on those 32 bit architectures which enable
the wrappers.

When enabled the syscall wrapper defines always take long parameters and then
cast them to whatever is needed. This approach doesn't work for the 32 bit
case where the original syscall takes a long long parameter, since we would
lose the upper 32 bits.
So syscalls with 64 bit arguments are special cases wrt to syscall wrappers
and enp up in the ugliness below (see also sys_fallocate). In addition these
special cased syscall wrappers have the drawback that ftrace syscall tracing
doesn't work on them, since they don't get defined by using the usual macros.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:56 -04:00
Eric Paris a1014f1023 fanotify: send events using read
Send events to userspace by reading the file descriptor from fanotify_init().
One will get blocks of data which look like:

struct fanotify_event_metadata {
	__u32 event_len;
	__u32 vers;
	__s32 fd;
	__u64 mask;
	__s64 pid;
	__u64 cookie;
} __attribute__ ((packed));

Simple code to retrieve and deal with events is below

	while ((len = read(fan_fd, buf, sizeof(buf))) > 0) {
		struct fanotify_event_metadata *metadata;

		metadata = (void *)buf;
		while(FAN_EVENT_OK(metadata, len)) {
			[PROCESS HERE!!]
			if (metadata->fd >= 0 && close(metadata->fd) != 0)
				goto fail;
			metadata = FAN_EVENT_NEXT(metadata, len);
		}
	}

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:56 -04:00
Eric Paris 2a3edf8604 fanotify: fanotify_mark syscall implementation
NAME
	fanotify_mark - add, remove, or modify an fanotify mark on a
filesystem object

SYNOPSIS
	int fanotify_mark(int fanotify_fd, unsigned int flags, u64 mask,
			  int dfd, const char *pathname)

DESCRIPTION
	fanotify_mark() is used to add remove or modify a mark on a filesystem
	object.  Marks are used to indicate that the fanotify group is
	interested in events which occur on that object.  At this point in
	time marks may only be added to files and directories.

	fanotify_fd must be a file descriptor returned by fanotify_init()

	The flags field must contain exactly one of the following:

	FAN_MARK_ADD - or the bits in mask and ignored mask into the mark
	FAN_MARK_REMOVE - bitwise remove the bits in mask and ignored mark
		from the mark

	The following values can be OR'd into the flags field:

	FAN_MARK_DONT_FOLLOW - same meaning as O_NOFOLLOW as described in open(2)
	FAN_MARK_ONLYDIR - same meaning as O_DIRECTORY as described in open(2)

	dfd may be any of the following:
	AT_FDCWD: the object will be lookup up based on pathname similar
		to open(2)

	file descriptor of a directory: if pathname is not NULL the
		object to modify will be lookup up similar to openat(2)

	file descriptor of the final object: if pathname is NULL the
		object to modify will be the object referenced by dfd

	The mask is the bitwise OR of the set of events of interest such as:
	FAN_ACCESS		- object was accessed (read)
	FAN_MODIFY		- object was modified (write)
	FAN_CLOSE_WRITE		- object was writable and was closed
	FAN_CLOSE_NOWRITE	- object was read only and was closed
	FAN_OPEN		- object was opened
	FAN_EVENT_ON_CHILD	- interested in objected that happen to
				  children.  Only relavent when the object
				  is a directory
	FAN_Q_OVERFLOW		- event queue overflowed (not implemented)

RETURN VALUE
	On success, this system call returns 0. On error, -1 is
	returned, and errno is set to indicate the error.

ERRORS
	EINVAL An invalid value was specified in flags.

	EINVAL An invalid value was specified in mask.

	EINVAL An invalid value was specified in ignored_mask.

	EINVAL fanotify_fd is not a file descriptor as returned by
	fanotify_init()

	EBADF fanotify_fd is not a valid file descriptor

	EBADF dfd is not a valid file descriptor and path is NULL.

	ENOTDIR dfd is not a directory and path is not NULL

	EACCESS no search permissions on some part of the path

	ENENT file not found

	ENOMEM Insufficient kernel memory is available.

CONFORMING TO
	These system calls are Linux-specific.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:56 -04:00
Eric Paris bbaa4168b2 fanotify: sys_fanotify_mark declartion
This patch simply declares the new sys_fanotify_mark syscall

int fanotify_mark(int fanotify_fd, unsigned int flags, u64_mask,
		  int dfd const char *pathname)

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:55 -04:00
Eric Paris 52c923dd07 fanotify: fanotify_init syscall implementation
NAME
	fanotify_init - initialize an fanotify group

SYNOPSIS
	int fanotify_init(unsigned int flags, unsigned int event_f_flags, int priority);

DESCRIPTION
	fanotify_init() initializes a new fanotify instance and returns a file
	descriptor associated with the new fanotify event queue.

	The following values can be OR'd into the flags field:

	FAN_NONBLOCK Set the O_NONBLOCK file status flag on the new open file description.
		Using this flag saves extra calls to fcntl(2) to achieve the same
		result.

	FAN_CLOEXEC Set the close-on-exec (FD_CLOEXEC) flag on the new file descriptor.
		See the description of the O_CLOEXEC flag in open(2) for reasons why
		this may be useful.

	The event_f_flags argument is unused and must be set to 0

	The priority argument is unused and must be set to 0

RETURN VALUE
	On success, this system call return a new file descriptor. On error, -1 is
	returned, and errno is set to indicate the error.

ERRORS
	EINVAL An invalid value was specified in flags.

	EINVAL A non-zero valid was passed in event_f_flags or in priority

	ENFILE The system limit on the total number of file descriptors has been reached.

	ENOMEM Insufficient kernel memory is available.

CONFORMING TO
	These system calls are Linux-specific.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:55 -04:00
Eric Paris 11637e4b7d fanotify: fanotify_init syscall declaration
This patch defines a new syscall fanotify_init() of the form:

int sys_fanotify_init(unsigned int flags, unsigned int event_f_flags,
		      unsigned int priority)

This syscall is used to create and fanotify group.  This is very similar to
the inotify_init() syscall.

Signed-off-by: Eric Paris <eparis@redhat.com>
2010-07-28 09:58:55 -04:00