Pull vfs directory delegations from Christian Brauner:
 "This contains the VFS prerequisites for supporting directory
  delegations in nfsd via CB_NOTIFY callbacks.

  The filelock core gains support for ignoring delegation breaks for
  directory change events together with an inode_lease_ignore_mask()
  helper, and fsnotify gains fsnotify_modify_mark_mask() and a
  FSNOTIFY_EVENT_RENAME data type.

  With this in place nfsd can request delegations on directories and set
  up inotify watches to trigger sending CB_NOTIFY events to clients
  instead of having every directory change break the delegation.

  New tracepoints are added to fsnotify() and to the start of
  break_lease(), and trace_break_lease_block() is passed the currently
  blocking lease instead of the new one.

  A follow-up fix moves the LEASE_BREAK_* flags out of
  #ifdef CONFIG_FILE_LOCKING to fix the build for CONFIG_FILE_LOCKING=n
  configurations"

* tag 'vfs-7.2-rc1.directory.delegations' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  filelock: move LEASE_BREAK_* flags out of #ifdef CONFIG_FILE_LOCKING
  fsnotify: add FSNOTIFY_EVENT_RENAME data type
  fsnotify: add fsnotify_modify_mark_mask()
  fsnotify: new tracepoint in fsnotify()
  filelock: add an inode_lease_ignore_mask helper
  filelock: add a tracepoint to start of break_lease()
  filelock: add support for ignoring deleg breaks for dir change events
  filelock: pass current blocking lease to trace_break_lease_block() rather than "new_fl"

Add a new fsnotify_rename_data struct and FSNOTIFY_EVENT_RENAME data
type that carries both the moved dentry and the inode that was
overwritten by the rename (if any).

Update fsnotify_data_inode(), fsnotify_data_dentry(), and
fsnotify_data_sb() to handle the new type, and add a new
fsnotify_data_rename_target() helper for extracting the overwritten
target inode.

Update fsnotify_move() to use the new data type for FS_RENAME and
FS_MOVED_TO events, passing the overwritten target inode through the
event data. FS_MOVED_FROM is unchanged since the source directory
doesn't need overwrite information.

This is done so that fsnotify consumers like nfsd can atomically
observe the overwritten file when a rename replaces an existing entry,
without needing a separate FS_DELETE event.

Assisted-by: Claude (Anthropic Claude Code)
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20260428-dir-deleg-v3-7-5a0780ba9def@kernel.org
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

nfsd needs to be able to modify the mask on an existing mark when new
directory delegations are set or unset. Add an exported function that
allows the caller to set and clear bits in the mark->mask, and does
the recalculation if something changed.

Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20260428-dir-deleg-v3-6-5a0780ba9def@kernel.org
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

fsnotify_get_mark_safe() may return false for a mark on an unrelated group,
which results in bypassing the permission check.

Fix by skipping over detached marks that are not in the current group.

CC: stable@vger.kernel.org
Fixes: abc77577a669 ("fsnotify: Provide framework for dropping SRCU lock in ->handle_event")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Link: https://patch.msgid.link/20260410144950.156160-1-mszeredi@redhat.com
Signed-off-by: Jan Kara <jack@suse.cz>

Introduce a linked list tracking all inode connectors for a superblock.
We will use this list when the superblock is getting shutdown to
properly clean up all the inode marks instead of relying on scanning all
inodes in the superblock which can get rather slow.

Suggested-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>

This is to make it easier to debug issues with AV software, which time and
again deadlocks with no indication of where the issue comes from, and the
kernel being blamed for the deadlock.  Then we need to analyze dumps to
prove that the kernel is not in fact at fault.

The deadlock comes from recursion: handling the event triggers another
permission event, in some roundabout way, obviously, otherwise it would
have been found in testing.

With this patch a warning is printed when permission event is received by
userspace but not answered for more than the timeout specified in
/proc/sys/fs/fanotify/watchdog_timeout.  The watchdog can be turned off by
setting the timeout to zero (which is the default).

The timeout is very coarse (T <= t < 2T) but I guess it's good enough for
the purpose.

Overhead should be minimal.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Link: https://patch.msgid.link/20250909143053.112171-1-mszeredi@redhat.com
Signed-off-by: Jan Kara <jack@suse.cz>

Pull fsnotify updates from Jan Kara:
 "Two fanotify cleanups and support for watching namespace-owned
  filesystems by namespace admins (most useful for being able to watch
  for new mounts / unmounts happening within a user namespace)"

* tag 'fsnotify_for_v6.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  fanotify: support watching filesystems and mounts inside userns
  fanotify: remove redundant permission checks
  fanotify: Drop use of flex array in fanotify_fh

An unprivileged user is allowed to create an fanotify group and add
inode marks, but not filesystem, mntns and mount marks.

Add limited support for setting up filesystem, mntns and mount marks by
an unprivileged user under the following conditions:

1.   User has CAP_SYS_ADMIN in the user ns where the group was created
2.a. User has CAP_SYS_ADMIN in the user ns where the sb was created
  OR (in case setting up a mntns mark)
2.b. User has CAP_SYS_ADMIN in the user ns associated with the mntns

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20250516192803.838659-3-amir73il@gmail.com

fanotify_mark(fd, FAN_MARK_FLUSH | FAN_MARK_MNTNS, ...) incorrectly
ends up causing removal inode marks.

Fixes: 0f46d81f2bce ("fanotify: notify on mount attach and detach")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20250418193903.2607617-2-amir73il@gmail.com

This is just the plumbing between the event source (fs/namespace.c) and the
event consumer (fanotify).  In itself it does nothing.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Link: https://lore.kernel.org/r/20250129165803.72138-2-mszeredi@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>