fanotify: add support for create/attrib/move/delete events

Add support for events with data type FSNOTIFY_EVENT_INODE
(e.g. create/attrib/move/delete) for inode and filesystem mark types.

The "inode" events do not carry enough information (i.e. path) to
report event->fd, so we do not allow setting a mask for those events
unless group supports reporting fid.

The "inode" events are not supported on a mount mark, because they do
not carry enough information (i.e. path) to be filtered by mount point.

The "dirent" events (create/move/delete) report the fid of the parent
directory where events took place without specifying the filename of the
child. In the future, fanotify may get support for reporting filename
information for those events.

Cc: <linux-api@vger.kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

2 files changed, 20 insertions, 1 deletions

diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index 974239b03442..158c69acb04d 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -313,9 +313,16 @@ static int fanotify_handle_event(struct fsnotify_group *group,
 
         BUILD_BUG_ON(FAN_ACCESS != FS_ACCESS);
         BUILD_BUG_ON(FAN_MODIFY != FS_MODIFY);
+        BUILD_BUG_ON(FAN_ATTRIB != FS_ATTRIB);
         BUILD_BUG_ON(FAN_CLOSE_NOWRITE != FS_CLOSE_NOWRITE);
         BUILD_BUG_ON(FAN_CLOSE_WRITE != FS_CLOSE_WRITE);
         BUILD_BUG_ON(FAN_OPEN != FS_OPEN);
+        BUILD_BUG_ON(FAN_MOVED_TO != FS_MOVED_TO);
+        BUILD_BUG_ON(FAN_MOVED_FROM != FS_MOVED_FROM);
+        BUILD_BUG_ON(FAN_CREATE != FS_CREATE);
+        BUILD_BUG_ON(FAN_DELETE != FS_DELETE);
+        BUILD_BUG_ON(FAN_DELETE_SELF != FS_DELETE_SELF);
+        BUILD_BUG_ON(FAN_MOVE_SELF != FS_MOVE_SELF);
         BUILD_BUG_ON(FAN_EVENT_ON_CHILD != FS_EVENT_ON_CHILD);
         BUILD_BUG_ON(FAN_Q_OVERFLOW != FS_Q_OVERFLOW);
         BUILD_BUG_ON(FAN_OPEN_PERM != FS_OPEN_PERM);
@@ -324,7 +331,7 @@ static int fanotify_handle_event(struct fsnotify_group *group,
         BUILD_BUG_ON(FAN_OPEN_EXEC != FS_OPEN_EXEC);
         BUILD_BUG_ON(FAN_OPEN_EXEC_PERM != FS_OPEN_EXEC_PERM);
 
-        BUILD_BUG_ON(HWEIGHT32(ALL_FANOTIFY_EVENT_BITS) != 12);
+        BUILD_BUG_ON(HWEIGHT32(ALL_FANOTIFY_EVENT_BITS) != 19);
 
         mask = fanotify_group_event_mask(group, iter_info, mask, data,
                                          data_type);
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index bf06fd6ef761..6c61a06d0ef5 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -976,6 +976,18 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
             group->priority == FS_PRIO_0)
                 goto fput_and_out;
 
+        /*
+         * Events with data type inode do not carry enough information to report
+         * event->fd, so we do not allow setting a mask for inode events unless
+         * group supports reporting fid.
+         * inode events are not supported on a mount mark, because they do not
+         * carry enough information (i.e. path) to be filtered by mount point.
+         */
+        if (mask & FANOTIFY_INODE_EVENTS &&
+            (!FAN_GROUP_FLAG(group, FAN_REPORT_FID) ||
+             mark_type == FAN_MARK_MOUNT))
+                goto fput_and_out;
+
         if (flags & FAN_MARK_FLUSH) {
                 ret = 0;
                 if (mark_type == FAN_MARK_MOUNT)