- 28 Jul, 2010 40 commits
-
-
Eric Paris authored
fanotify needs to know the actual event added to queues so it can be correctly checked for return values from userspace. To do this we need to pass that information from the merger code back to the main even handling routine. Currently that information is unused, but it will be. Signed-off-by:Eric Paris <eparis@redhat.com>
-
Eric Paris authored
Each group can define their own notification (and secondary_q) merge function. Inotify does tail drop, fanotify does matching and drop which can actually allocate a completely new event. But for fanotify to properly deal with permissions events it needs to know the new event which was ultimately added to the notification queue. This patch just implements a void ** argument which is passed to the merge function. fanotify can use this field to pass the new event back to higher layers. Signed-off-by: -
Eric Paris authored
This introduces an ordering to fsnotify groups. With purely asynchronous notification based "things" implementing fsnotify (inotify, dnotify) ordering isn't particularly important. But if people want to use fsnotify for the basis of sycronous notification or blocking notification ordering becomes important. eg. A Hierarchical Storage Management listener would need to get its event before an AV scanner could get its event (since the HSM would need to bring the data in for the AV scanner to scan.) Typically asynchronous notification would want to run after the AV scanner made any relevant access decisions so as to not send notification about an event that was denied. Signed-off-by: -
Eric Paris authored
fanotify listeners may want to clear all marks. They may want to do this to destroy all of their inode marks which have nothing but ignores. Realistically this is useful for av vendors who update policy and want to clear all of their cached allows. Signed-off-by: -
Eric Paris authored
Some users may want to truely ignore an inode even if it has been modified. Say you are wanting a mount which contains a log file and you really don't want any notification about that file. This patch allows the listener to do that. Signed-off-by: -
Eric Paris authored
Some inodes a group may want to never hear about a set of events even if the inode is modified. We add a new mark flag which indicates that these marks should not have their ignored_mask cleared on modification. Signed-off-by: -
Eric Paris authored
On inode modification we clear the ignored mask for all of the marks on the inode. This allows userspace to ignore accesses to inodes until there is something different. Signed-off-by: -
Eric Paris authored
Change the sys_fanotify_mark() system call so users can set ignored_masks on inodes. Remember, if a user new sets a real mask, and only sets ignored masks, the ignore will never be pinned in memory. Thus ignored_masks can be lost under memory pressure and the user may again get events they previously thought were ignored. Signed-off-by: -
Eric Paris authored
When fanotify receives an event it will check event->mask & ~ignored_mask. If no bits are left the event will not be sent. Signed-off-by: -
Eric Paris authored
The ignored_mask is a new mask which is part of fsnotify marks. A group's should_send_event() function can use the ignored mask to determine that certain events are not of interest. In particular if a group registers a mask including FS_OPEN on a vfsmount they could add FS_OPEN to the ignored_mask for individual inodes and not send open events for those inodes. Signed-off-by: -
Eric Paris authored
inotify marks must pin inodes in core. dnotify doesn't technically need to since they are closed when the directory is closed. fanotify also need to pin inodes in core as it works today. But the next step is to introduce the concept of 'ignored masks' which is actually a mask of events for an inode of no interest. I claim that these should be liberally sent to the kernel and should not pin the inode in core. If the inode is brought back in the listener will get an event it may have thought excluded, but this is not a serious situation and one any listener should deal with. This patch lays the ground work for non-pinning inode marks by using lazy inode pinning. We do not pin a mark until it has a non-zero mask entry. If a listener new sets a mask we never pin the inode. Signed-off-by: -
Andreas Gruenbacher authored
A number of validity checks on outgoing data are done in static inlines but are only used in one place. Instead just do them where they are used for readability. Signed-off-by:
Andreas Gruenbacher <agruen@suse.de> Signed-off-by:
-
Andreas Gruenbacher authored
fanotify_mark_validate functions are all needlessly declared in headers as static inlines. Instead just do the checks where they are needed for code readability. Signed-off-by:
-
Andreas Gruenbacher authored
split fanotify_remove_mark into fanotify_remove_inode_mark and fanotify_remove_vfsmount_mark. Signed-off-by:
-
Andreas Gruenbacher authored
the term 'vfsmount' isn't sensicle to userspace. instead call is 'mount. Signed-off-by:
-
Eric Paris authored
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: -
Andreas Gruenbacher authored
fanotify_add_mark now does nothing useful anymore, drop it. Signed-off-by:
-
Andreas Gruenbacher authored
No need to return the mark from fanotify_add_*_mark to fanotify_add_mark Signed-off-by:
-
Andreas Gruenbacher authored
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 authored
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 authored
fanotify_update_mark() doesn't do much useful; remove it. Signed-off-by:
-
Eric Paris authored
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 authored
currently should_send_event in fanotify only cares about marks on inodes. This patch extends that interface to indicate that it cares about events that happened on vfsmounts. Signed-off-by: -
Andreas Gruenbacher authored
Per-mount watches allow groups to listen to fsnotify events on an entire mount. This patch simply adds and initializes the fields needed in the vfsmount struct to make this happen. Signed-off-by:
-
Eric Paris authored
Much like inode-mark.c has all of the code dealing with marks on inodes this patch adds a vfsmount-mark.c which has similar code but is intended for marks on vfsmounts. Signed-off-by: -
Andreas Gruenbacher authored
This patch adds the list and mask fields needed to support vfsmount marks. These are the same fields fsnotify needs on an inode. They are not used, just declared and we note where the cleanup hook should be (the function is not yet defined) Signed-off-by:
-
Eric Paris authored
Currently fsnotify_init_mark sets some fields to 0/NULL. Some users already used some sorts of zalloc, some didn't. This patch uses memset to explicitly zero everything in the fsnotify_mark when it is initialized so we don't have to be careful if fields are later added to marks. Signed-off-by: -
Eric Paris authored
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: -
Andreas Gruenbacher authored
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 authored
Code cleanup which does the fd creation work seperately from the userspace metadata creation. It fits better with the other code. Signed-off-by:
-
Heiko Carstens authored
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: -
Paul Mundt authored
fanotify references anon_inode_getfd(), which is only available with ANON_INODES enabled. Presently this bails out with the following: LD vmlinux fs/built-in.o: In function `sys_fanotify_init': (.text+0x26d1c): undefined reference to `anon_inode_getfd' make: *** [vmlinux] Error 1 which is trivially corrected by adding an ANON_INODES select. Signed-off-by:
Paul Mundt <lethal@linux-sh.org> Signed-off-by:
-
Eric Paris authored
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 authored
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 authored
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 authored
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 authored
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 authored
Currently if 2 events are going to be merged on the notication queue with different masks the second event will be cloned and will replace the first event. However if this notification queue is the only place referencing the event in question there is no reason not to just update the event in place. We can tell this if the event->refcnt == 1. Since we hold a reference for each queue this event is on we know that when refcnt == 1 this is the only queue. The other concern is that it might be about to be added to a new queue, but this can't be the case since fsnotify holds a reference on the event until it is finished adding it to queues. Signed-off-by: -
Eric Paris authored
Instead of just merging fanotify events if they are exactly the same, merge notification events with different masks. To do this we have to clone the old event, update the mask in the new event with the new merged mask, and put the new event in place of the old event. Signed-off-by: -
Eric Paris authored
fanotify listeners get an open file descriptor to the object in question so the ordering of operations is not as important as in other notification systems. inotify will drop events if the last event in the event FIFO is the same as the current event. This patch will drop fanotify events if they are the same as another event anywhere in the event FIFO. Signed-off-by:
-
