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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
