Dan Carpenter says:
> Commit 5866efa8 ("SUNRPC: Fix svcauth_gss_proxy_init()") from Oct
> 24, 2019 (linux-next), leads to the following Smatch static checker
> warning:
>
> 	net/sunrpc/auth_gss/svcauth_gss.c:1039 gss_free_in_token_pages()
> 	warn: iterator 'i' not incremented
>
> net/sunrpc/auth_gss/svcauth_gss.c
>     1034 static void gss_free_in_token_pages(struct gssp_in_token *in_token)
>     1035 {
>     1036         u32 inlen;
>     1037         int i;
>     1038
> --> 1039         i = 0;
>     1040         inlen = in_token->page_len;
>     1041         while (inlen) {
>     1042                 if (in_token->pages[i])
>     1043                         put_page(in_token->pages[i]);
>                                                          ^
> This puts page zero over and over.
>
>     1044                 inlen -= inlen > PAGE_SIZE ? PAGE_SIZE : inlen;
>     1045         }
>     1046
>     1047         kfree(in_token->pages);
>     1048         in_token->pages = NULL;
>     1049 }

Based on the way that the ->pages[] array is constructed in
gss_read_proxy_verf(), we know that once the loop encounters a NULL
page pointer, the remaining array elements must also be NULL.
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Suggested-by: Trond Myklebust <trondmy@hammerspace.com>
Fixes: 5866efa8 ("SUNRPC: Fix svcauth_gss_proxy_init()")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

NFSERR_OPNOTSUPP is not described by any RFC, and should not be used.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

The 'NFS error' NFSERR_OPNOTSUPP is not described by any of the official
NFS related RFCs, but appears to have snuck into some older .x files for
NFSv2.
Either way, it is not in RFC1094, RFC1813 or any of the NFSv4 RFCs, so
should not be returned by the knfsd server, and particularly not by the
"LOOKUP" operation.

Instead, let's return NFSERR_STALE, which is more appropriate if the
filesystem encodes the filehandle as FILEID_INVALID.

Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

When security labeling is enabled, the client can pass a file security
label as part of a create operation for the new file, similar to mode
and other attributes. At present, the security label is received by nfsd
and passed down to nfsd_create_setattr(), but nfsd_setattr() is never
called and therefore the label is never set on the new file. This bug
may have been introduced on or around commit d6a97d3f ("NFSD:
add security label to struct nfsd_attrs"). Looking at nfsd_setattr()
I am uncertain as to whether the same issue presents for
file ACLs and therefore requires a similar fix for those.

An alternative approach would be to introduce a new LSM hook to set the
"create SID" of the current task prior to the actual file creation, which
would atomically label the new inode at creation time. This would be better
for SELinux and a similar approach has been used previously
(see security_dentry_create_files_as) but perhaps not usable by other LSMs.

Reproducer:
1. Install a Linux distro with SELinux - Fedora is easiest
2. git clone https://github.com/SELinuxProject/selinux-testsuite
3. Install the requisite dependencies per selinux-testsuite/README.md
4. Run something like the following script:
MOUNT=$HOME/selinux-testsuite
sudo systemctl start nfs-server
sudo exportfs -o rw,no_root_squash,security_label localhost:$MOUNT
sudo mkdir -p /mnt/selinux-testsuite
sudo mount -t nfs -o vers=4.2 localhost:$MOUNT /mnt/selinux-testsuite
pushd /mnt/selinux-testsuite/
sudo make -C policy load
pushd tests/filesystem
sudo runcon -t test_filesystem_t ./create_file -f trans_test_file \
	-e test_filesystem_filetranscon_t -v
sudo rm -f trans_test_file
popd
sudo make -C policy unload
popd
sudo umount /mnt/selinux-testsuite
sudo exportfs -u localhost:$MOUNT
sudo rmdir /mnt/selinux-testsuite
sudo systemctl stop nfs-server

Expected output:
<eliding noise from commands run prior to or after the test itself>
Process context:
	unconfined_u:unconfined_r:test_filesystem_t:s0-s0:c0.c1023
Created file: trans_test_file
File context: unconfined_u:object_r:test_filesystem_filetranscon_t:s0
File context is correct

Actual output:
<eliding noise from commands run prior to or after the test itself>
Process context:
	unconfined_u:unconfined_r:test_filesystem_t:s0-s0:c0.c1023
Created file: trans_test_file
File context: system_u:object_r:test_file_t:s0
File context error, expected:
	test_filesystem_filetranscon_t
got:
	test_file_t
Signed-off-by: Stephen Smalley <stephen.smalley.work@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Clients that send an OFFLOAD_STATUS might want to distinguish
between an async COPY operation that is still running, has
completed successfully, or that has failed.

The intention of this patch is to make NFSD behave like this:

 * Copy still running:
	OFFLOAD_STATUS returns NFS4_OK, the number of bytes copied
	so far, and an empty osr_status array
 * Copy completed successfully:
	OFFLOAD_STATUS returns NFS4_OK, the number of bytes copied,
	and an osr_status of NFS4_OK
 * Copy failed:
	OFFLOAD_STATUS returns NFS4_OK, the number of bytes copied,
	and an osr_status other than NFS4_OK
 * Copy operation lost, canceled, or otherwise unrecognized:
	OFFLOAD_STATUS returns NFS4ERR_BAD_STATEID

NB: Though RFC 7862 Section 11.2 lists a small set of NFS status
codes that are valid for OFFLOAD_STATUS, there do not seem to be any
explicit spec limits on the status codes that may be returned in the
osr_status field.

At this time we have no unit tests for COPY and its brethren, as
pynfs does not yet implement support for NFSv4.2.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

After a client has started an asynchronous COPY operation, a
subsequent OFFLOAD_STATUS operation will need to report the status
code once that COPY operation has completed. The recorded status
record will be used by a subsequent patch.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

It is obsolete since sp_lock was discarded in commit 580a2575
("SUNRPC: discard sp_lock").
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Introduce write_ports netlink command. For listener-set, userspace is
expected to provide a NFS listeners list it wants enabled. All other
sockets will be closed.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Co-developed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

svc_find_listener will return the transport instance pointer for the
endpoint accepting connections/peer traffic from the specified transport
class and matching sockaddr.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Add svc_xprt_create_from_sa utility routine and refactor
svc_xprt_create() codebase in order to introduce the capability to
create a svc port from socket address.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Introduce write_version netlink command through a "declarative" interface.
This patch introduces a change in behavior since for version-set userspace
is expected to provide a NFS major/minor version list it wants to enable
while all the other ones will be disabled. (procfs write_version
command implements imperative interface where the admin writes +3/-3 to
enable/disable a single version.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Introduce write_threads netlink command similar to the one available
through the procfs.
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Co-developed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Currently admins set this by using unshare to create a new uts
namespace, and then resetting the hostname. With the new netlink
interface we can just pass this in directly. Prepare nfsd_svc for
this change.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Currently nfsd_svc holds the nfsd_mutex over the whole function. For
some of the later netlink patches though, we want to do some other
things to the server before starting it. Move the mutex handling into
the callers.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

In 'nlm_alloc_host', the host has already been assigned a value of NULL
when defined, so 'host=NULL;' Can be deleted.
Signed-off-by: Li kunyu <kunyu@nfschina.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

When CONFIG_NFSD_LEGACY_CLIENT_TRACKING is not set, the virtual file
  /proc/fs/nfsd/nfsv4recoverydir
is created but responds EINVAL to any access.
This is not useful, is somewhat surprising, and it causes ltp to
complain.

The only known user of this file is in nfs-utils, which handles
non-existence and read-failure equally well.  So there is nothing to
gain from leaving the file present but inaccessible.

So this patch removes the file when its content is not available - i.e.
when that config option is not selected.

Also remove the #ifdef which hides some of the enum values when
CONFIG_NFSD_V$ not selection.  simple_fill_super() quietly ignores array
entries that are not present, so having slots in the array that don't
get used is perfectly acceptable.  So there is no value in this #ifdef.
Reported-by: Petr Vorel <pvorel@suse.cz>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Fixes: 74fd4873 ("nfsd: new Kconfig option for legacy client tracking")
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

recalculate_deny_mode() takes time that is linear in the number of
stateids active on the file.

When called from
  release_openowner -> free_ol_stateid_reaplist ->nfs4_free_ol_stateid
  -> release_all_access

the number of times it is called is linear in the number of stateids.
The net result is that time taken by release_openowner is quadratic in
the number of stateids.

When the nfsd server is shut down while there are many active stateids
this can result in a soft lockup. ("CPU stuck for 302s" seen in one case).

In many cases all the states have the same deny modes and there is no
need to examine the entire list in recalculate_deny_mode().  In
particular, recalculate_deny_mode() will only reduce the deny mode,
never increase it.  So if some prefix of the list causes the original
deny mode to be required, there is no need to examine the remainder of
the list.

So we can improve recalculate_deny_mode() to usually run in constant
time, so release_openowner will typically be only linear in the number
of states.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Show client info alongside the number of cl_rpc_users. If that's
elevated, then we can infer that this function returned nfserr_jukebox.

[ cel: For additional debugging of RPC user refcounting ]
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Vladimir Benes <vbenes@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Replace a dprintk in check_slot_seqid with tracepoints. These new
tracepoints track slot sequence numbers during operation.
Suggested-by: Jeffrey Layton <jlayton@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

We never want a newline in tracepoint output.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Vladimir Benes <vbenes@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

since vs_proc pointer is dereferenced before getting it's address there's
no need to check for NULL.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 8e5b6773 ("SUNRPC: Add a callback to initialise server requests")
Signed-off-by: Aleksandr Aprelkov <aaprelkov@usergate.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Use group allocation/free of per-cpu counters api to accelerate
nfsd percpu_counters init/destroy(), and also squash the
nfsd_percpu_counters_init/reset/destroy() and nfsd_counters_init/destroy()
into callers to simplify code.
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

This adds basic infrastructure for handing GET_DIR_DELEGATION calls from
clients, including the decoders and encoders. For now, it always just
returns NFS4_OK + GDD4_UNAVAIL.

Eventually clients may start sending this operation, and it's better if
we can return GDD4_UNAVAIL instead of having to abort the whole compound.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Commit 88382036 ("nfsd: update workqueue creation") made the
callback_wq single-threaded, presumably to protect modifications of
cl_cb_client. See documenting comment for nfsd4_process_cb_update().

However, cl_cb_client is per-lease. There's no other reason that all
callback operations need to be dispatched via a single thread. The
single threading here means all client callbacks can be blocked by a
problem with one client.

Change the NFSv4 callback client so it serializes per-lease instead
of serializing all NFSv4 callback operations on the server.
Reported-by: Dai Ngo <dai.ngo@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

move_to_close_lru() is currently called with ->st_mutex held.
This can lead to a deadlock as move_to_close_lru() waits for sc_count to
drop to 2, and some threads holding a reference might be waiting for the
mutex.  These references will never be dropped so sc_count will never
reach 2.

There can be no harm in dropping ->st_mutex before
move_to_close_lru() because the only place that takes the mutex is
nfsd4_lock_ol_stateid(), and it quickly aborts if sc_type is
NFS4_CLOSED_STID, which it will be before move_to_close_lru() is called.

See also
 https://lore.kernel.org/lkml/4dd1fe21e11344e5969bb112e954affb@jd.com/T/
where this problem was raised but not successfully resolved.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

move_to_close_lru() waits for sc_count to become zero while holding
rp_mutex.  This can deadlock if another thread holds a reference and is
waiting for rp_mutex.

By the time we get to move_to_close_lru() the openowner is unhashed and
cannot be found any more.  So code waiting for the mutex can safely
retry the lookup if move_to_close_lru() has started.

So change rp_mutex to an atomic_t with three states:

 RP_UNLOCK   - state is still hashed, not locked for reply
 RP_LOCKED   - state is still hashed, is locked for reply
 RP_UNHASHED - state is not hashed, no code can get a lock.

Use wait_var_event() to wait for either a lock, or for the owner to be
unhashed.  In the latter case, retry the lookup.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Rather than taking the rp_mutex (via nfsd4_cstate_assign_replay) in
nfsd4_cleanup_open_state() (which seems counter-intuitive), take it and
assign rp_owner as soon as possible - in nfsd4_process_open1().

This will support a future change when nfsd4_cstate_assign_replay() might
fail.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Currently find_openstateowner_str look ups are done both in
nfsd4_process_open1() and alloc_init_open_stateowner() - the latter
possibly being a surprise based on its name.

It would be easier to follow, and more conformant to common patterns, if
the lookup was all in the one place.

So replace alloc_init_open_stateowner() with
find_or_alloc_open_stateowner() and use the latter in
nfsd4_process_open1() without any calls to find_openstateowner_str().

This means all finds are find_openstateowner_str_locked() and
find_openstateowner_str() is no longer needed.  So discard
find_openstateowner_str() and rename find_openstateowner_str_locked() to
find_openstateowner_str().
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

epoll can call out to vfs_poll() with a file pointer that may race with
the last 'fput()'. That would make f_count go down to zero, and while
the ep->mtx locking means that the resulting file pointer tear-down will
be blocked until the poll returns, it means that f_count is already
dead, and any use of it won't actually get a reference to the file any
more: it's dead regardless.

Make sure we have a valid ref on the file pointer before we call down to
vfs_poll() from the epoll routines.

Link: https://lore.kernel.org/lkml/0000000000002d631f0615918f1e@google.com/
Reported-by: syzbot+045b454ab35fd82a35fb@syzkaller.appspotmail.com
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull EDAC fixes from Borislav Petkov:

 - Fix error logging and check user-supplied data when injecting an
   error in the versal EDAC driver

* tag 'edac_urgent_for_v6.9_rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
  EDAC/versal: Do not log total error counts
  EDAC/versal: Check user-supplied data before injecting an error
  EDAC/versal: Do not register for NOC errors

Pull powerpc fixes from Michael Ellerman:

 - Fix incorrect delay handling in the plpks (keystore) code

 - Fix a panic when an LPAR boots with a frozen PE

Thanks to Andrew Donnellan, Gaurav Batra, Nageswara R Sastry, and Nayna
Jain.

* tag 'powerpc-6.9-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/pseries/iommu: LPAR panics during boot up with a frozen PE
  powerpc/pseries: make max polling consistent for longer H_CALLs

Pull misc x86 fixes from Ingo Molnar:

 - Remove the broken vsyscall emulation code from
   the page fault code

 - Fix kexec crash triggered by certain SEV RMP
   table layouts

 - Fix unchecked MSR access error when disabling
   the x2APIC via iommu=off

* tag 'x86-urgent-2024-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Remove broken vsyscall emulation code from the page fault code
  x86/apic: Don't access the APIC when disabling x2APIC
  x86/sev: Add callback to apply RMP table fixups for kexec
  x86/e820: Add a new e820 table update helper

Pull irq fix from Ingo Molnar:
 "Fix suspicious RCU usage in __do_softirq()"

* tag 'irq-urgent-2024-05-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  softirq: Fix suspicious RCU usage in __do_softirq()

Pull char/misc driver fixes from Greg KH:
 "Here are some small char/misc/other driver fixes and new device ids
  for 6.9-rc7 that resolve some reported problems.

  Included in here are:

   - iio driver fixes

   - mei driver fix and new device ids

   - dyndbg bugfix

   - pvpanic-pci driver bugfix

   - slimbus driver bugfix

   - fpga new device id

  All have been in linux-next with no reported problems"

* tag 'char-misc-6.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  slimbus: qcom-ngd-ctrl: Add timeout for wait operation
  dyndbg: fix old BUG_ON in >control parser
  misc/pvpanic-pci: register attributes via pci_driver
  fpga: dfl-pci: add PCI subdevice ID for Intel D5005 card
  mei: me: add lunar lake point M DID
  mei: pxp: match against PCI_CLASS_DISPLAY_OTHER
  iio:imu: adis16475: Fix sync mode setting
  iio: accel: mxc4005: Reset chip on probe() and resume()
  iio: accel: mxc4005: Interrupt handling fixes
  dt-bindings: iio: health: maxim,max30102: fix compatible check
  iio: pressure: Fixes SPI support for BMP3xx devices
  iio: pressure: Fixes BME280 SPI driver data

Pull USB driver fixes from Greg KH:
 "Here are some small USB driver fixes for reported problems for
  6.9-rc7. Included in here are:

   - usb core fixes for found issues

   - typec driver fixes for reported problems

   - usb gadget driver fixes for reported problems

   - xhci build fixes

   - dwc3 driver fixes for reported issues

  All of these have been in linux-next this past week with no reported
  problems"

* tag 'usb-6.9-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: typec: tcpm: Check for port partner validity before consuming it
  usb: typec: tcpm: enforce ready state when queueing alt mode vdm
  usb: typec: tcpm: unregister existing source caps before re-registration
  usb: typec: tcpm: clear pd_event queue in PORT_RESET
  usb: typec: tcpm: queue correct sop type in tcpm_queue_vdm_unlocked
  usb: Fix regression caused by invalid ep0 maxpacket in virtual SuperSpeed device
  usb: ohci: Prevent missed ohci interrupts
  usb: typec: qcom-pmic: fix pdphy start() error handling
  usb: typec: qcom-pmic: fix use-after-free on late probe errors
  usb: gadget: f_fs: Fix a race condition when processing setup packets.
  USB: core: Fix access violation during port device removal
  usb: dwc3: core: Prevent phy suspend during init
  usb: xhci-plat: Don't include xhci.h
  usb: gadget: uvc: use correct buffer size when parsing configfs lists
  usb: gadget: composite: fix OS descriptors w_value logic
  usb: gadget: f_fs: Fix race between aio_cancel() and AIO request complete

Pull input fixes from Dmitry Torokhov:

 - a new ID for ASUS ROG RAIKIRI controllers added to xpad driver

 - amimouse driver structure annotated with __refdata to prevent section
   mismatch warnings.

* tag 'input-for-v6.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: amimouse - mark driver struct with __refdata to prevent section mismatch
  Input: xpad - add support for ASUS ROG RAIKIRI

Merge tag 'probes-fixes-v6.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull probes fix from Masami Hiramatsu:

 - probe-events: Fix memory leak in parsing probe argument.

   There is a memory leak (forget to free an allocated buffer) in a
   memory allocation failure path. Fix it to jump to the correct error
   handling code.

* tag 'probes-fixes-v6.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/probes: Fix memory leak in traceprobe_parse_probe_arg_body()

Pull tracing and tracefs fixes from Steven Rostedt:

 - Fix RCU callback of freeing an eventfs_inode.

   The freeing of the eventfs_inode from the kref going to zero freed
   the contents of the eventfs_inode and then used kfree_rcu() to free
   the inode itself. But the contents should also be protected by RCU.
   Switch to a call_rcu() that calls a function to free all of the
   eventfs_inode after the RCU synchronization.

 - The tracing subsystem maps its own descriptor to a file represented
   by eventfs. The freeing of this descriptor needs to know when the
   last reference of an eventfs_inode is released, but currently there
   is no interface for that.

   Add a "release" callback to the eventfs_inode entry array that allows
   for freeing of data that can be referenced by the eventfs_inode being
   opened. Then increment the ref counter for this descriptor when the
   eventfs_inode file is created, and decrement/free it when the last
   reference to the eventfs_inode is released and the file is removed.
   This prevents races between freeing the descriptor and the opening of
   the eventfs file.

 - Fix the permission processing of eventfs.

   The change to make the permissions of eventfs default to the mount
   point but keep track of when changes were made had a side effect that
   could cause security concerns. When the tracefs is remounted with a
   given gid or uid, all the files within it should inherit that gid or
   uid. But if the admin had changed the permission of some file within
   the tracefs file system, it would not get updated by the remount.

   This caused the kselftest of file permissions to fail the second time
   it is run. The first time, all changes would look fine, but the
   second time, because the changes were "saved", the remount did not
   reset them.

   Create a link list of all existing tracefs inodes, and clear the
   saved flags on them on a remount if the remount changes the
   corresponding gid or uid fields.

   This also simplifies the code by removing the distinction between the
   toplevel eventfs and an instance eventfs. They should both act the
   same. They were different because of a misconception due to the
   remount not resetting the flags. Now that remount resets all the
   files and directories to default to the root node if a uid/gid is
   specified, it makes the logic simpler to implement.

* tag 'trace-v6.9-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  eventfs: Have "events" directory get permissions from its parent
  eventfs: Do not treat events directory different than other directories
  eventfs: Do not differentiate the toplevel events directory
  tracefs: Still use mount point as default permissions for instances
  tracefs: Reset permissions on remount if permissions are options
  eventfs: Free all of the eventfs_inode after RCU
  eventfs/tracing: Add callback for release of an eventfs_inode

Pull dma-mapping fix from Christoph Hellwig:

 - fix the combination of restricted pools and dynamic swiotlb
   (Will Deacon)

* tag 'dma-mapping-6.9-2024-05-04' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: initialise restricted pool list_head when SWIOTLB_DYNAMIC=y