Pull slab updates from Vlastimil Babka:
 "This time it's mostly refactoring and improving APIs for slab users in
  the kernel, along with some debugging improvements.

   - kmem_cache_create() refactoring (Christian Brauner)

     Over the years have been growing new parameters to
     kmem_cache_create() where most of them are needed only for a small
     number of caches - most recently the rcu_freeptr_offset parameter.

     To avoid adding new parameters to kmem_cache_create() and adjusting
     all its callers, or creating new wrappers such as
     kmem_cache_create_rcu(), we can now pass extra parameters using the
     new struct kmem_cache_args. Not explicitly initialized fields
     default to values interpreted as unused.

     kmem_cache_create() is for now a wrapper that works both with the
     new form: kmem_cache_create(name, object_size, args, flags) and the
     legacy form: kmem_cache_create(name, object_size, align, flags,
     ctor)

   - kmem_cache_destroy() waits for kfree_rcu()'s in flight (Vlastimil
     Babka, Uladislau Rezki)

     Since SLOB removal, kfree() is allowed for freeing objects
     allocated by kmem_cache_create(). By extension kfree_rcu() as
     allowed as well, which can allow converting simple call_rcu()
     callbacks that only do kmem_cache_free(), as there was never a
     kmem_cache_free_rcu() variant. However, for caches that can be
     destroyed e.g. on module removal, the cache owners knew to issue
     rcu_barrier() first to wait for the pending call_rcu()'s, and this
     is not sufficient for pending kfree_rcu()'s due to its internal
     batching optimizations. Ulad has provided a new
     kvfree_rcu_barrier() and to make the usage less error-prone,
     kmem_cache_destroy() calls it. Additionally, destroying
     SLAB_TYPESAFE_BY_RCU caches now again issues rcu_barrier()
     synchronously instead of using an async work, because the past
     motivation for async work no longer applies. Users of custom
     call_rcu() callbacks should however keep calling rcu_barrier()
     before cache destruction.

   - Debugging use-after-free in SLAB_TYPESAFE_BY_RCU caches (Jann Horn)

     Currently, KASAN cannot catch UAFs in such caches as it is legal to
     access them within a grace period, and we only track the grace
     period when trying to free the underlying slab page. The new
     CONFIG_SLUB_RCU_DEBUG option changes the freeing of individual
     object to be RCU-delayed, after which KASAN can poison them.

   - Delayed memcg charging (Shakeel Butt)

     In some cases, the memcg is uknown at allocation time, such as
     receiving network packets in softirq context. With
     kmem_cache_charge() these may be now charged later when the user
     and its memcg is known.

   - Misc fixes and improvements (Pedro Falcato, Axel Rasmussen,
     Christoph Lameter, Yan Zhen, Peng Fan, Xavier)"

* tag 'slab-for-6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: (34 commits)
  mm, slab: restore kerneldoc for kmem_cache_create()
  io_uring: port to struct kmem_cache_args
  slab: make __kmem_cache_create() static inline
  slab: make kmem_cache_create_usercopy() static inline
  slab: remove kmem_cache_create_rcu()
  file: port to struct kmem_cache_args
  slab: create kmem_cache_create() compatibility layer
  slab: port KMEM_CACHE_USERCOPY() to struct kmem_cache_args
  slab: port KMEM_CACHE() to struct kmem_cache_args
  slab: remove rcu_freeptr_offset from struct kmem_cache
  slab: pass struct kmem_cache_args to do_kmem_cache_create()
  slab: pull kmem_cache_open() into do_kmem_cache_create()
  slab: pass struct kmem_cache_args to create_cache()
  slab: port kmem_cache_create_usercopy() to struct kmem_cache_args
  slab: port kmem_cache_create_rcu() to struct kmem_cache_args
  slab: port kmem_cache_create() to struct kmem_cache_args
  slab: add struct kmem_cache_args
  slab: s/__kmem_cache_create/do_kmem_cache_create/g
  memcg: add charging of already allocated slab objects
  mm/slab: Optimize the code logic in find_mergeable()
  ...

Pull vfs file updates from Christian Brauner:
 "This is the work to cleanup and shrink struct file significantly.

  Right now, (focusing on x86) struct file is 232 bytes. After this
  series struct file will be 184 bytes aka 3 cacheline and a spare 8
  bytes for future extensions at the end of the struct.

  With struct file being as ubiquitous as it is this should make a
  difference for file heavy workloads and allow further optimizations in
  the future.

   - struct fown_struct was embedded into struct file letting it take up
     32 bytes in total when really it shouldn't even be embedded in
     struct file in the first place. Instead, actual users of struct
     fown_struct now allocate the struct on demand. This frees up 24
     bytes.

   - Move struct file_ra_state into the union containg the cleanup hooks
     and move f_iocb_flags out of the union. This closes a 4 byte hole
     we created earlier and brings struct file to 192 bytes. Which means
     struct file is 3 cachelines and we managed to shrink it by 40
     bytes.

   - Reorder struct file so that nothing crosses a cacheline.

     I suspect that in the future we will end up reordering some members
     to mitigate false sharing issues or just because someone does
     actually provide really good perf data.

   - Shrinking struct file to 192 bytes is only part of the work.

     Files use a slab that is SLAB_TYPESAFE_BY_RCU and when a kmem cache
     is created with SLAB_TYPESAFE_BY_RCU the free pointer must be
     located outside of the object because the cache doesn't know what
     part of the memory can safely be overwritten as it may be needed to
     prevent object recycling.

     That has the consequence that SLAB_TYPESAFE_BY_RCU may end up
     adding a new cacheline.

     So this also contains work to add a new kmem_cache_create_rcu()
     function that allows the caller to specify an offset where the
     freelist pointer is supposed to be placed. Thus avoiding the
     implicit addition of a fourth cacheline.

   - And finally this removes the f_version member in struct file.

     The f_version member isn't particularly well-defined. It is mainly
     used as a cookie to detect concurrent seeks when iterating
     directories. But it is also abused by some subsystems for
     completely unrelated things.

     It is mostly a directory and filesystem specific thing that doesn't
     really need to live in struct file and with its wonky semantics it
     really lacks a specific function.

     For pipes, f_version is (ab)used to defer poll notifications until
     a write has happened. And struct pipe_inode_info is used by
     multiple struct files in their ->private_data so there's no chance
     of pushing that down into file->private_data without introducing
     another pointer indirection.

     But pipes don't rely on f_pos_lock so this adds a union into struct
     file encompassing f_pos_lock and a pipe specific f_pipe member that
     pipes can use. This union of course can be extended to other file
     types and is similar to what we do in struct inode already"

* tag 'vfs-6.12.file' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (26 commits)
  fs: remove f_version
  pipe: use f_pipe
  fs: add f_pipe
  ubifs: store cookie in private data
  ufs: store cookie in private data
  udf: store cookie in private data
  proc: store cookie in private data
  ocfs2: store cookie in private data
  input: remove f_version abuse
  ext4: store cookie in private data
  ext2: store cookie in private data
  affs: store cookie in private data
  fs: add generic_llseek_cookie()
  fs: use must_set_pos()
  fs: add must_set_pos()
  fs: add vfs_setpos_cookie()
  s390: remove unused f_version
  ceph: remove unused f_version
  adi: remove unused f_version
  mm: Removed @freeptr_offset to prevent doc warning
  ...

Only regular files with FMODE_ATOMIC_POS and directories need
f_pos_lock. Place a new f_pipe member in a union with f_pos_lock
that they can use and make them stop abusing f_version in follow-up
patches.

Link: https://lore.kernel.org/r/20240830-vfs-file-f_version-v1-18-6d3e4816aa7b@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Port filp_cache to struct kmem_cache_args.

Reviewed-by: Kees Cook <kees@kernel.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>

Switch to the new kmem_cache_create_rcu() helper which allows us to use
a custom free pointer offset avoiding the need to have an external free
pointer which would grow struct file behind our backs.

Link: https://lore.kernel.org/r/20240828-work-kmem_cache-rcu-v3-3-5460bc1f09f6@kernel.org
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>

We do embedd struct fown_struct into struct file letting it take up 32
bytes in total. We could tweak struct fown_struct to be more compact but
really it shouldn't even be embedded in struct file in the first place.

Instead, actual users of struct fown_struct should allocate the struct
on demand. This frees up 24 bytes in struct file.

That will have some potentially user-visible changes for the ownership
fcntl()s. Some of them can now fail due to allocation failures.
Practically, that probably will almost never happen as the allocations
are small and they only happen once per file.

The fown_struct is used during kill_fasync() which is used by e.g.,
pipes to generate a SIGIO signal. Sending of such signals is conditional
on userspace having set an owner for the file using one of the F_OWNER
fcntl()s. Such users will be unaffected if struct fown_struct is
allocated during the fcntl() call.

There are a few subsystems that call __f_setown() expecting
file->f_owner to be allocated:

(1) tun devices
    file->f_op->fasync::tun_chr_fasync()
    -> __f_setown()

    There are no callers of tun_chr_fasync().

(2) tty devices

    file->f_op->fasync::tty_fasync()
    -> __tty_fasync()
       -> __f_setown()

    tty_fasync() has no additional callers but __tty_fasync() has. Note
    that __tty_fasync() only calls __f_setown() if the @on argument is
    true. It's called from:

    file->f_op->release::tty_release()
    -> tty_release()
       -> __tty_fasync()
          -> __f_setown()

    tty_release() calls __tty_fasync() with @on false
    => __f_setown() is never called from tty_release().
       => All callers of tty_release() are safe as well.

    file->f_op->release::tty_open()
    -> tty_release()
       -> __tty_fasync()
          -> __f_setown()

    __tty_hangup() calls __tty_fasync() with @on false
    => __f_setown() is never called from tty_release().
       => All callers of __tty_hangup() are safe as well.

From the callchains it's obvious that (1) and (2) end up getting called
via file->f_op->fasync(). That can happen either through the F_SETFL
fcntl() with the FASYNC flag raised or via the FIOASYNC ioctl(). If
FASYNC is requested and the file isn't already FASYNC then
file->f_op->fasync() is called with @on true which ends up causing both
(1) and (2) to call __f_setown().

(1) and (2) are the only subsystems that call __f_setown() from the
file->f_op->fasync() handler. So both (1) and (2) have been updated to
allocate a struct fown_struct prior to calling fasync_helper() to
register with the fasync infrastructure. That's safe as they both call
fasync_helper() which also does allocations if @on is true.

The other interesting case are file leases:

(3) file leases
    lease_manager_ops->lm_setup::lease_setup()
    -> __f_setown()

    Which in turn is called from:

    generic_add_lease()
    -> lease_manager_ops->lm_setup::lease_setup()
       -> __f_setown()

So here again we can simply make generic_add_lease() allocate struct
fown_struct prior to the lease_manager_ops->lm_setup::lease_setup()
which happens under a spinlock.

With that the two remaining subsystems that call __f_setown() are:

(4) dnotify
(5) sockets

Both have their own custom ioctls to set struct fown_struct and both
have been converted to allocate a struct fown_struct on demand from
their respective ioctls.

Interactions with O_PATH are fine as well e.g., when opening a /dev/tty
as O_PATH then no file->f_op->open() happens thus no file->f_owner is
allocated. That's fine as no file operation will be set for those and
the device has never been opened. fcntl()s called on such things will
just allocate a ->f_owner on demand. Although I have zero idea why'd you
care about f_owner on an O_PATH fd.

Link: https://lore.kernel.org/r/20240813-work-f_owner-v2-1-4e9343a79f9f@kernel.org
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Fixed-
	WARNING: Missing a blank line after declarations
	WARNING: Missing a blank line after declarations
	Declaration format: improved struct file declaration format

Signed-off-by: Mohit0404 <mohitpawar@mitaoe.ac.in>
Link: https://lore.kernel.org/r/20240727072134.130962-2-mohitpawar@mitaoe.ac.in
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>

const qualify the struct ctl_table argument in the proc_handler function
signatures. This is a prerequisite to moving the static ctl_table
structs into .rodata data which will ensure that proc_handler function
pointers cannot be modified.

This patch has been generated by the following coccinelle script:

```
  virtual patch

  @r1@
  identifier ctl, write, buffer, lenp, ppos;
  identifier func !~ "appldata_(timer|interval)_handler|sched_(rt|rr)_handler|rds_tcp_skbuf_handler|proc_sctp_do_(hmac_alg|rto_min|rto_max|udp_port|alpha_beta|auth|probe_interval)";
  @@

  int func(
  - struct ctl_table *ctl
  + const struct ctl_table *ctl
    ,int write, void *buffer, size_t *lenp, loff_t *ppos);

  @r2@
  identifier func, ctl, write, buffer, lenp, ppos;
  @@

  int func(
  - struct ctl_table *ctl
  + const struct ctl_table *ctl
    ,int write, void *buffer, size_t *lenp, loff_t *ppos)
  { ... }

  @r3@
  identifier func;
  @@

  int func(
  - struct ctl_table *
  + const struct ctl_table *
    ,int , void *, size_t *, loff_t *);

  @r4@
  identifier func, ctl;
  @@

  int func(
  - struct ctl_table *ctl
  + const struct ctl_table *ctl
    ,int , void *, size_t *, loff_t *);

  @r5@
  identifier func, write, buffer, lenp, ppos;
  @@

  int func(
  - struct ctl_table *
  + const struct ctl_table *
    ,int write, void *buffer, size_t *lenp, loff_t *ppos);

```

* Code formatting was adjusted in xfs_sysctl.c to comply with code
  conventions. The xfs_stats_clear_proc_handler,
  xfs_panic_mask_proc_handler and xfs_deprecated_dointvec_minmax where
  adjusted.

* The ctl_table argument in proc_watchdog_common was const qualified.
  This is called from a proc_handler itself and is calling back into
  another proc_handler, making it necessary to change it as part of the
  proc_handler migration.

Co-developed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Co-developed-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Joel Granados <j.granados@samsung.com>

Pull lsm updates from Paul Moore:

 - Promote IMA/EVM to a proper LSM

   This is the bulk of the diffstat, and the source of all the changes
   in the VFS code. Prior to the start of the LSM stacking work it was
   important that IMA/EVM were separate from the rest of the LSMs,
   complete with their own hooks, infrastructure, etc. as it was the
   only way to enable IMA/EVM at the same time as a LSM.

   However, now that the bulk of the LSM infrastructure supports
   multiple simultaneous LSMs, we can simplify things greatly by
   bringing IMA/EVM into the LSM infrastructure as proper LSMs. This is
   something I've wanted to see happen for quite some time and Roberto
   was kind enough to put in the work to make it happen.

 - Use the LSM hook default values to simplify the call_int_hook() macro

   Previously the call_int_hook() macro required callers to supply a
   default return value, despite a default value being specified when
   the LSM hook was defined.

   This simplifies the macro by using the defined default return value
   which makes life easier for callers and should also reduce the number
   of return value bugs in the future (we've had a few pop up recently,
   hence this work).

 - Use the KMEM_CACHE() macro instead of kmem_cache_create()

   The guidance appears to be to use the KMEM_CACHE() macro when
   possible and there is no reason why we can't use the macro, so let's
   use it.

 - Fix a number of comment typos in the LSM hook comment blocks

   Not much to say here, we fixed some questionable grammar decisions in
   the LSM hook comment blocks.

* tag 'lsm-pr-20240312' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: (28 commits)
  cred: Use KMEM_CACHE() instead of kmem_cache_create()
  lsm: use default hook return value in call_int_hook()
  lsm: fix typos in security/security.c comment headers
  integrity: Remove LSM
  ima: Make it independent from 'integrity' LSM
  evm: Make it independent from 'integrity' LSM
  evm: Move to LSM infrastructure
  ima: Move IMA-Appraisal to LSM infrastructure
  ima: Move to LSM infrastructure
  integrity: Move integrity_kernel_module_request() to IMA
  security: Introduce key_post_create_or_update hook
  security: Introduce inode_post_remove_acl hook
  security: Introduce inode_post_set_acl hook
  security: Introduce inode_post_create_tmpfile hook
  security: Introduce path_post_mknod hook
  security: Introduce file_release hook
  security: Introduce file_post_open hook
  security: Introduce inode_post_removexattr hook
  security: Introduce inode_post_setattr hook
  security: Align inode_setattr hook definition with EVM
  ...

When we open block devices as files we want to make sure to not charge
them against the open file limit of the caller as that can cause
spurious failures.

Link: https://lore.kernel.org/r/20240123-vfs-bdev-file-v2-1-adbd023e19cc@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>