Commit Graph

3603 Commits

Author SHA1 Message Date
Linus Torvalds
c1649ec557 nfsd-6.2 fixes:
- Fix recently introduced use-after-free bugs
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Merge tag 'nfsd-6.2-4' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd fixes from Chuck Lever:

 - Fix recently introduced use-after-free bugs

* tag 'nfsd-6.2-4' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  NFSD: replace delayed_work with work_struct for nfsd_client_shrinker
  NFSD: register/unregister of nfsd-client shrinker at nfsd startup/shutdown time
  NFSD: fix use-after-free in nfsd4_ssc_setup_dul()
2023-01-17 09:29:17 -08:00
Dai Ngo
7c24fa2250 NFSD: replace delayed_work with work_struct for nfsd_client_shrinker
Since nfsd4_state_shrinker_count always calls mod_delayed_work with
0 delay, we can replace delayed_work with work_struct to save some
space and overhead.

Also add the call to cancel_work after unregister the shrinker
in nfs4_state_shutdown_net.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-01-12 09:38:30 -05:00
Dai Ngo
f385f7d244 NFSD: register/unregister of nfsd-client shrinker at nfsd startup/shutdown time
Currently the nfsd-client shrinker is registered and unregistered at
the time the nfsd module is loaded and unloaded. The problem with this
is the shrinker is being registered before all of the relevant fields
in nfsd_net are initialized when nfsd is started. This can lead to an
oops when memory is low and the shrinker is called while nfsd is not
running.

This patch moves the  register/unregister of nfsd-client shrinker from
module load/unload time to nfsd startup/shutdown time.

Fixes: 44df6f439a ("NFSD: add delegation reaper to react to low memory condition")
Reported-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-01-11 21:32:05 -05:00
Xingyuan Mo
e6cf91b7b4 NFSD: fix use-after-free in nfsd4_ssc_setup_dul()
If signal_pending() returns true, schedule_timeout() will not be executed,
causing the waiting task to remain in the wait queue.
Fixed by adding a call to finish_wait(), which ensures that the waiting
task will always be removed from the wait queue.

Fixes: f4e44b3933 ("NFSD: delay unmount source's export after inter-server copy completed.")
Signed-off-by: Xingyuan Mo <hdthky0@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-01-11 21:29:11 -05:00
Linus Torvalds
7dd4b804e0 nfsd-6.2 fixes:
- Fix a race when creating NFSv4 files
 - Revert the use of relaxed bitops
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Merge tag 'nfsd-6.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd fixes from Chuck Lever:

 - Fix a race when creating NFSv4 files

 - Revert the use of relaxed bitops

* tag 'nfsd-6.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  NFSD: Use set_bit(RQ_DROPME)
  Revert "SUNRPC: Use RMW bitops in single-threaded hot paths"
  nfsd: fix handling of cached open files in nfsd4_open codepath
2023-01-10 15:03:06 -06:00
Chuck Lever
5304930dba NFSD: Use set_bit(RQ_DROPME)
The premise that "Once an svc thread is scheduled and executing an
RPC, no other processes will touch svc_rqst::rq_flags" is false.
svc_xprt_enqueue() examines the RQ_BUSY flag in scheduled nfsd
threads when determining which thread to wake up next.

Fixes: 9315564747 ("NFSD: Use only RQ_DROPME to signal the need to drop a reply")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-01-07 10:16:33 -05:00
Chuck Lever
7827c81f02 Revert "SUNRPC: Use RMW bitops in single-threaded hot paths"
The premise that "Once an svc thread is scheduled and executing an
RPC, no other processes will touch svc_rqst::rq_flags" is false.
svc_xprt_enqueue() examines the RQ_BUSY flag in scheduled nfsd
threads when determining which thread to wake up next.

Found via KCSAN.

Fixes: 28df098881 ("SUNRPC: Use RMW bitops in single-threaded hot paths")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-01-06 13:17:12 -05:00
Jeff Layton
0b3a551fa5 nfsd: fix handling of cached open files in nfsd4_open codepath
Commit fb70bf124b ("NFSD: Instantiate a struct file when creating a
regular NFSv4 file") added the ability to cache an open fd over a
compound. There are a couple of problems with the way this currently
works:

It's racy, as a newly-created nfsd_file can end up with its PENDING bit
cleared while the nf is hashed, and the nf_file pointer is still zeroed
out. Other tasks can find it in this state and they expect to see a
valid nf_file, and can oops if nf_file is NULL.

Also, there is no guarantee that we'll end up creating a new nfsd_file
if one is already in the hash. If an extant entry is in the hash with a
valid nf_file, nfs4_get_vfs_file will clobber its nf_file pointer with
the value of op_file and the old nf_file will leak.

Fix both issues by making a new nfsd_file_acquirei_opened variant that
takes an optional file pointer. If one is present when this is called,
we'll take a new reference to it instead of trying to open the file. If
the nfsd_file already has a valid nf_file, we'll just ignore the
optional file and pass the nfsd_file back as-is.

Also rework the tracepoints a bit to allow for an "opened" variant and
don't try to avoid counting acquisitions in the case where we already
have a cached open file.

Fixes: fb70bf124b ("NFSD: Instantiate a struct file when creating a regular NFSv4 file")
Cc: Trond Myklebust <trondmy@hammerspace.com>
Reported-by: Stanislav Saner <ssaner@redhat.com>
Reported-and-Tested-by: Ruben Vestergaard <rubenv@drcmr.dk>
Reported-and-Tested-by: Torkil Svensgaard <torkil@drcmr.dk>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-01-06 13:17:06 -05:00
Linus Torvalds
b61778fa51 nfsd-6.2 fixes:
- Fix a filecache UAF during NFSD shutdown
 - Avoid exposing automounted mounts on NFS re-exports
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Merge tag 'nfsd-6.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd fixes from Chuck Lever:

 - Fix a filecache UAF during NFSD shutdown

 - Avoid exposing automounted mounts on NFS re-exports

* tag 'nfsd-6.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  nfsd: fix handling of readdir in v4root vs. mount upcall timeout
  nfsd: shut down the NFSv4 state objects before the filecache
2023-01-04 11:26:36 -08:00
Jeff Layton
cad853374d nfsd: fix handling of readdir in v4root vs. mount upcall timeout
If v4 READDIR operation hits a mountpoint and gets back an error,
then it will include that entry in the reply and set RDATTR_ERROR for it
to the error.

That's fine for "normal" exported filesystems, but on the v4root, we
need to be more careful to only expose the existence of dentries that
lead to exports.

If the mountd upcall times out while checking to see whether a
mountpoint on the v4root is exported, then we have no recourse other
than to fail the whole operation.

Cc: Steve Dickson <steved@redhat.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=216777
Reported-by: JianHong Yin <yin-jianhong@163.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: <stable@vger.kernel.org>
2023-01-02 10:45:31 -05:00
Jeff Layton
789e1e10f2 nfsd: shut down the NFSv4 state objects before the filecache
Currently, we shut down the filecache before trying to clean up the
stateids that depend on it. This leads to the kernel trying to free an
nfsd_file twice, and a refcount overput on the nf_mark.

Change the shutdown procedure to tear down all of the stateids prior
to shutting down the filecache.

Reported-and-tested-by: Wang Yugui <wangyugui@e16-tech.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Fixes: 5e113224c1 ("nfsd: nfsd_file cache entries should be per net namespace")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-22 10:12:56 -05:00
Linus Torvalds
aeba12b26c nfsd-6.2 supplement:
- Address numerous reports of refcount underflows in NFSD's filecache
 - Address a UAF in callback setup error handling
 - Address a UAF during server-to-server copy
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Merge tag 'nfsd-6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull more nfsd updates from Chuck Lever:
 "This contains a number of crasher fixes that were not ready for the
  initial pull request last week.

  In particular, Jeff's patch attempts to address reference count
  underflows in NFSD's filecache, which have been very difficult to
  track down because there is no reliable reproducer.

  Common failure modes:
      https://bugzilla.kernel.org/show_bug.cgi?id=216691#c11
      https://bugzilla.kernel.org/show_bug.cgi?id=216674#c6
      https://bugzilla.redhat.com/show_bug.cgi?id=2138605

  The race windows were found by inspection and the clean-ups appear
  sensible and pass regression testing, so we include them here in the
  hope that they address the problem. However we remain vigilant because
  we don't have 100% certainty yet that the problem is fully addressed.

  Summary:

   - Address numerous reports of refcount underflows in NFSD's filecache

   - Address a UAF in callback setup error handling

   - Address a UAF during server-to-server copy"

* tag 'nfsd-6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  NFSD: fix use-after-free in __nfs42_ssc_open()
  nfsd: under NFSv4.1, fix double svc_xprt_put on rpc_create failure
  nfsd: rework refcounting in filecache
2022-12-19 09:10:33 -06:00
Linus Torvalds
48ea09cdda hardening updates for v6.2-rc1
- Convert flexible array members, fix -Wstringop-overflow warnings,
   and fix KCFI function type mismatches that went ignored by
   maintainers (Gustavo A. R. Silva, Nathan Chancellor, Kees Cook).
 
 - Remove the remaining side-effect users of ksize() by converting
   dma-buf, btrfs, and coredump to using kmalloc_size_roundup(),
   add more __alloc_size attributes, and introduce full testing
   of all allocator functions. Finally remove the ksize() side-effect
   so that each allocation-aware checker can finally behave without
   exceptions.
 
 - Introduce oops_limit (default 10,000) and warn_limit (default off)
   to provide greater granularity of control for panic_on_oops and
   panic_on_warn (Jann Horn, Kees Cook).
 
 - Introduce overflows_type() and castable_to_type() helpers for
   cleaner overflow checking.
 
 - Improve code generation for strscpy() and update str*() kern-doc.
 
 - Convert strscpy and sigphash tests to KUnit, and expand memcpy
   tests.
 
 - Always use a non-NULL argument for prepare_kernel_cred().
 
 - Disable structleak plugin in FORTIFY KUnit test (Anders Roxell).
 
 - Adjust orphan linker section checking to respect CONFIG_WERROR
   (Xin Li).
 
 - Make sure siginfo is cleared for forced SIGKILL (haifeng.xu).
 
 - Fix um vs FORTIFY warnings for always-NULL arguments.
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Merge tag 'hardening-v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull kernel hardening updates from Kees Cook:

 - Convert flexible array members, fix -Wstringop-overflow warnings, and
   fix KCFI function type mismatches that went ignored by maintainers
   (Gustavo A. R. Silva, Nathan Chancellor, Kees Cook)

 - Remove the remaining side-effect users of ksize() by converting
   dma-buf, btrfs, and coredump to using kmalloc_size_roundup(), add
   more __alloc_size attributes, and introduce full testing of all
   allocator functions. Finally remove the ksize() side-effect so that
   each allocation-aware checker can finally behave without exceptions

 - Introduce oops_limit (default 10,000) and warn_limit (default off) to
   provide greater granularity of control for panic_on_oops and
   panic_on_warn (Jann Horn, Kees Cook)

 - Introduce overflows_type() and castable_to_type() helpers for cleaner
   overflow checking

 - Improve code generation for strscpy() and update str*() kern-doc

 - Convert strscpy and sigphash tests to KUnit, and expand memcpy tests

 - Always use a non-NULL argument for prepare_kernel_cred()

 - Disable structleak plugin in FORTIFY KUnit test (Anders Roxell)

 - Adjust orphan linker section checking to respect CONFIG_WERROR (Xin
   Li)

 - Make sure siginfo is cleared for forced SIGKILL (haifeng.xu)

 - Fix um vs FORTIFY warnings for always-NULL arguments

* tag 'hardening-v6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (31 commits)
  ksmbd: replace one-element arrays with flexible-array members
  hpet: Replace one-element array with flexible-array member
  um: virt-pci: Avoid GCC non-NULL warning
  signal: Initialize the info in ksignal
  lib: fortify_kunit: build without structleak plugin
  panic: Expose "warn_count" to sysfs
  panic: Introduce warn_limit
  panic: Consolidate open-coded panic_on_warn checks
  exit: Allow oops_limit to be disabled
  exit: Expose "oops_count" to sysfs
  exit: Put an upper limit on how often we can oops
  panic: Separate sysctl logic from CONFIG_SMP
  mm/pgtable: Fix multiple -Wstringop-overflow warnings
  mm: Make ksize() a reporting-only function
  kunit/fortify: Validate __alloc_size attribute results
  drm/sti: Fix return type of sti_{dvo,hda,hdmi}_connector_mode_valid()
  drm/fsl-dcu: Fix return type of fsl_dcu_drm_connector_mode_valid()
  driver core: Add __alloc_size hint to devm allocators
  overflow: Introduce overflows_type() and castable_to_type()
  coredump: Proactively round up to kmalloc bucket size
  ...
2022-12-14 12:20:00 -08:00
Dai Ngo
75333d48f9 NFSD: fix use-after-free in __nfs42_ssc_open()
Problem caused by source's vfsmount being unmounted but remains
on the delayed unmount list. This happens when nfs42_ssc_open()
return errors.

Fixed by removing nfsd4_interssc_connect(), leave the vfsmount
for the laundromat to unmount when idle time expires.

We don't need to call nfs_do_sb_deactive when nfs42_ssc_open
return errors since the file was not opened so nfs_server->active
was not incremented. Same as in nfsd4_copy, if we fail to
launch nfsd4_do_async_copy thread then there's no need to
call nfs_do_sb_deactive

Reported-by: Xingyuan Mo <hdthky0@gmail.com>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Tested-by: Xingyuan Mo <hdthky0@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-14 10:11:54 -05:00
Linus Torvalds
764822972d NFSD 6.2 Release Notes
This release introduces support for the CB_RECALL_ANY operation.
 NFSD can send this operation to request that clients return any
 delegations they choose. The server uses this operation to handle
 low memory scenarios or indicate to a client when that client has
 reached the maximum number of delegations the server supports.
 
 The NFSv4.2 READ_PLUS operation has been simplified temporarily
 whilst support for sparse files in local filesystems and the VFS is
 improved.
 
 Two major data structure fixes appear in this release:
 
 * The nfs4_file hash table is replaced with a resizable hash table
   to reduce the latency of NFSv4 OPEN operations.
 
 * Reference counting in the NFSD filecache has been hardened against
   races.
 
 In furtherance of removing support for NFSv2 in a subsequent kernel
 release, a new Kconfig option enables server-side support for NFSv2
 to be left out of a kernel build.
 
 MAINTAINERS has been updated to indicate that changes to fs/exportfs
 should go through the NFSD tree.
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Merge tag 'nfsd-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd updates from Chuck Lever:
 "This release introduces support for the CB_RECALL_ANY operation. NFSD
  can send this operation to request that clients return any delegations
  they choose. The server uses this operation to handle low memory
  scenarios or indicate to a client when that client has reached the
  maximum number of delegations the server supports.

  The NFSv4.2 READ_PLUS operation has been simplified temporarily whilst
  support for sparse files in local filesystems and the VFS is improved.

  Two major data structure fixes appear in this release:

   - The nfs4_file hash table is replaced with a resizable hash table to
     reduce the latency of NFSv4 OPEN operations.

   - Reference counting in the NFSD filecache has been hardened against
     races.

  In furtherance of removing support for NFSv2 in a subsequent kernel
  release, a new Kconfig option enables server-side support for NFSv2 to
  be left out of a kernel build.

  MAINTAINERS has been updated to indicate that changes to fs/exportfs
  should go through the NFSD tree"

* tag 'nfsd-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (49 commits)
  NFSD: Avoid clashing function prototypes
  SUNRPC: Fix crasher in unwrap_integ_data()
  SUNRPC: Make the svc_authenticate tracepoint conditional
  NFSD: Use only RQ_DROPME to signal the need to drop a reply
  SUNRPC: Clean up xdr_write_pages()
  SUNRPC: Don't leak netobj memory when gss_read_proxy_verf() fails
  NFSD: add CB_RECALL_ANY tracepoints
  NFSD: add delegation reaper to react to low memory condition
  NFSD: add support for sending CB_RECALL_ANY
  NFSD: refactoring courtesy_client_reaper to a generic low memory shrinker
  trace: Relocate event helper files
  NFSD: pass range end to vfs_fsync_range() instead of count
  lockd: fix file selection in nlmsvc_cancel_blocked
  lockd: ensure we use the correct file descriptor when unlocking
  lockd: set missing fl_flags field when retrieving args
  NFSD: Use struct_size() helper in alloc_session()
  nfsd: return error if nfs4_setacl fails
  lockd: set other missing fields when unlocking files
  NFSD: Add an nfsd_file_fsync tracepoint
  sunrpc: svc: Remove an unused static function svc_ungetu32()
  ...
2022-12-12 20:54:39 -08:00
Linus Torvalds
6a518afcc2 fs.acl.rework.v6.2
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Merge tag 'fs.acl.rework.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping

Pull VFS acl updates from Christian Brauner:
 "This contains the work that builds a dedicated vfs posix acl api.

  The origins of this work trace back to v5.19 but it took quite a while
  to understand the various filesystem specific implementations in
  sufficient detail and also come up with an acceptable solution.

  As we discussed and seen multiple times the current state of how posix
  acls are handled isn't nice and comes with a lot of problems: The
  current way of handling posix acls via the generic xattr api is error
  prone, hard to maintain, and type unsafe for the vfs until we call
  into the filesystem's dedicated get and set inode operations.

  It is already the case that posix acls are special-cased to death all
  the way through the vfs. There are an uncounted number of hacks that
  operate on the uapi posix acl struct instead of the dedicated vfs
  struct posix_acl. And the vfs must be involved in order to interpret
  and fixup posix acls before storing them to the backing store, caching
  them, reporting them to userspace, or for permission checking.

  Currently a range of hacks and duct tape exist to make this work. As
  with most things this is really no ones fault it's just something that
  happened over time. But the code is hard to understand and difficult
  to maintain and one is constantly at risk of introducing bugs and
  regressions when having to touch it.

  Instead of continuing to hack posix acls through the xattr handlers
  this series builds a dedicated posix acl api solely around the get and
  set inode operations.

  Going forward, the vfs_get_acl(), vfs_remove_acl(), and vfs_set_acl()
  helpers must be used in order to interact with posix acls. They
  operate directly on the vfs internal struct posix_acl instead of
  abusing the uapi posix acl struct as we currently do. In the end this
  removes all of the hackiness, makes the codepaths easier to maintain,
  and gets us type safety.

  This series passes the LTP and xfstests suites without any
  regressions. For xfstests the following combinations were tested:
   - xfs
   - ext4
   - btrfs
   - overlayfs
   - overlayfs on top of idmapped mounts
   - orangefs
   - (limited) cifs

  There's more simplifications for posix acls that we can make in the
  future if the basic api has made it.

  A few implementation details:

   - The series makes sure to retain exactly the same security and
     integrity module permission checks. Especially for the integrity
     modules this api is a win because right now they convert the uapi
     posix acl struct passed to them via a void pointer into the vfs
     struct posix_acl format to perform permission checking on the mode.

     There's a new dedicated security hook for setting posix acls which
     passes the vfs struct posix_acl not a void pointer. Basing checking
     on the posix acl stored in the uapi format is really unreliable.
     The vfs currently hacks around directly in the uapi struct storing
     values that frankly the security and integrity modules can't
     correctly interpret as evidenced by bugs we reported and fixed in
     this area. It's not necessarily even their fault it's just that the
     format we provide to them is sub optimal.

   - Some filesystems like 9p and cifs need access to the dentry in
     order to get and set posix acls which is why they either only
     partially or not even at all implement get and set inode
     operations. For example, cifs allows setxattr() and getxattr()
     operations but doesn't allow permission checking based on posix
     acls because it can't implement a get acl inode operation.

     Thus, this patch series updates the set acl inode operation to take
     a dentry instead of an inode argument. However, for the get acl
     inode operation we can't do this as the old get acl method is
     called in e.g., generic_permission() and inode_permission(). These
     helpers in turn are called in various filesystem's permission inode
     operation. So passing a dentry argument to the old get acl inode
     operation would amount to passing a dentry to the permission inode
     operation which we shouldn't and probably can't do.

     So instead of extending the existing inode operation Christoph
     suggested to add a new one. He also requested to ensure that the
     get and set acl inode operation taking a dentry are consistently
     named. So for this version the old get acl operation is renamed to
     ->get_inode_acl() and a new ->get_acl() inode operation taking a
     dentry is added. With this we can give both 9p and cifs get and set
     acl inode operations and in turn remove their complex custom posix
     xattr handlers.

     In the future I hope to get rid of the inode method duplication but
     it isn't like we have never had this situation. Readdir is just one
     example. And frankly, the overall gain in type safety and the more
     pleasant api wise are simply too big of a benefit to not accept
     this duplication for a while.

   - We've done a full audit of every codepaths using variant of the
     current generic xattr api to get and set posix acls and
     surprisingly it isn't that many places. There's of course always a
     chance that we might have missed some and if so I'm sure we'll find
     them soon enough.

     The crucial codepaths to be converted are obviously stacking
     filesystems such as ecryptfs and overlayfs.

     For a list of all callers currently using generic xattr api helpers
     see [2] including comments whether they support posix acls or not.

   - The old vfs generic posix acl infrastructure doesn't obey the
     create and replace semantics promised on the setxattr(2) manpage.
     This patch series doesn't address this. It really is something we
     should revisit later though.

  The patches are roughly organized as follows:

   (1) Change existing set acl inode operation to take a dentry
       argument (Intended to be a non-functional change)

   (2) Rename existing get acl method (Intended to be a non-functional
       change)

   (3) Implement get and set acl inode operations for filesystems that
       couldn't implement one before because of the missing dentry.
       That's mostly 9p and cifs (Intended to be a non-functional
       change)

   (4) Build posix acl api, i.e., add vfs_get_acl(), vfs_remove_acl(),
       and vfs_set_acl() including security and integrity hooks
       (Intended to be a non-functional change)

   (5) Implement get and set acl inode operations for stacking
       filesystems (Intended to be a non-functional change)

   (6) Switch posix acl handling in stacking filesystems to new posix
       acl api now that all filesystems it can stack upon support it.

   (7) Switch vfs to new posix acl api (semantical change)

   (8) Remove all now unused helpers

   (9) Additional regression fixes reported after we merged this into
       linux-next

  Thanks to Seth for a lot of good discussion around this and
  encouragement and input from Christoph"

* tag 'fs.acl.rework.v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping: (36 commits)
  posix_acl: Fix the type of sentinel in get_acl
  orangefs: fix mode handling
  ovl: call posix_acl_release() after error checking
  evm: remove dead code in evm_inode_set_acl()
  cifs: check whether acl is valid early
  acl: make vfs_posix_acl_to_xattr() static
  acl: remove a slew of now unused helpers
  9p: use stub posix acl handlers
  cifs: use stub posix acl handlers
  ovl: use stub posix acl handlers
  ecryptfs: use stub posix acl handlers
  evm: remove evm_xattr_acl_change()
  xattr: use posix acl api
  ovl: use posix acl api
  ovl: implement set acl method
  ovl: implement get acl method
  ecryptfs: implement set acl method
  ecryptfs: implement get acl method
  ksmbd: use vfs_remove_acl()
  acl: add vfs_remove_acl()
  ...
2022-12-12 18:46:39 -08:00
Linus Torvalds
75f4d9af8b iov_iter work; most of that is about getting rid of
direction misannotations and (hopefully) preventing
 more of the same for the future.
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull iov_iter updates from Al Viro:
 "iov_iter work; most of that is about getting rid of direction
  misannotations and (hopefully) preventing more of the same for the
  future"

* tag 'pull-iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  use less confusing names for iov_iter direction initializers
  iov_iter: saner checks for attempt to copy to/from iterator
  [xen] fix "direction" argument of iov_iter_kvec()
  [vhost] fix 'direction' argument of iov_iter_{init,bvec}()
  [target] fix iov_iter_bvec() "direction" argument
  [s390] memcpy_real(): WRITE is "data source", not destination...
  [s390] zcore: WRITE is "data source", not destination...
  [infiniband] READ is "data destination", not source...
  [fsi] WRITE is "data source", not destination...
  [s390] copy_oldmem_kernel() - WRITE is "data source", not destination
  csum_and_copy_to_iter(): handle ITER_DISCARD
  get rid of unlikely() on page_copy_sane() calls
2022-12-12 18:29:54 -08:00
Linus Torvalds
73fa58dca8 File locking changes for v6.2.
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Merge tag 'locks-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux

Pull file locking updates from Jeff Layton:
 "The main change here is to add the new locks_inode_context helper, and
  convert all of the places that dereference inode->i_flctx directly to
  use that instead.

  There is a new helper to indicate whether any locks are held on an
  inode. This is mostly for Ceph but may be usable elsewhere too.

  Andi Kleen requested that we print the PID when the LOCK_MAND warning
  fires, to help track down applications trying to use it.

  Finally, we added some new warnings to some of the file locking
  functions that fire when the ->fl_file and filp arguments differ. This
  helped us find some long-standing bugs in lockd. Patches for those are
  in Chuck Lever's tree and should be in his v6.2 PR. After that patch,
  people using NFSv2/v3 locking may see some warnings fire until those
  go in.

  Happy Holidays!"

* tag 'locks-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
  Add process name and pid to locks warning
  nfsd: use locks_inode_context helper
  nfs: use locks_inode_context helper
  lockd: use locks_inode_context helper
  ksmbd: use locks_inode_context helper
  cifs: use locks_inode_context helper
  ceph: use locks_inode_context helper
  filelock: add a new locks_inode_context accessor function
  filelock: new helper: vfs_inode_has_locks
  filelock: WARN_ON_ONCE when ->fl_file and filp don't match
2022-12-12 08:52:53 -08:00
Dan Aloni
3bc8edc98b nfsd: under NFSv4.1, fix double svc_xprt_put on rpc_create failure
On error situation `clp->cl_cb_conn.cb_xprt` should not be given
a reference to the xprt otherwise both client cleanup and the
error handling path of the caller call to put it. Better to
delay handing over the reference to a later branch.

[   72.530665] refcount_t: underflow; use-after-free.
[   72.531933] WARNING: CPU: 0 PID: 173 at lib/refcount.c:28 refcount_warn_saturate+0xcf/0x120
[   72.533075] Modules linked in: nfsd(OE) nfsv4(OE) nfsv3(OE) nfs(OE) lockd(OE) compat_nfs_ssc(OE) nfs_acl(OE) rpcsec_gss_krb5(OE) auth_rpcgss(OE) rpcrdma(OE) dns_resolver fscache netfs grace rdma_cm iw_cm ib_cm sunrpc(OE) mlx5_ib mlx5_core mlxfw pci_hyperv_intf ib_uverbs ib_core xt_MASQUERADE nf_conntrack_netlink nft_counter xt_addrtype nft_compat br_netfilter bridge stp llc nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set overlay nf_tables nfnetlink crct10dif_pclmul crc32_pclmul ghash_clmulni_intel xfs serio_raw virtio_net virtio_blk net_failover failover fuse [last unloaded: sunrpc]
[   72.540389] CPU: 0 PID: 173 Comm: kworker/u16:5 Tainted: G           OE     5.15.82-dan #1
[   72.541511] Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.16.0-3.module+el8.7.0+1084+97b81f61 04/01/2014
[   72.542717] Workqueue: nfsd4_callbacks nfsd4_run_cb_work [nfsd]
[   72.543575] RIP: 0010:refcount_warn_saturate+0xcf/0x120
[   72.544299] Code: 55 00 0f 0b 5d e9 01 50 98 00 80 3d 75 9e 39 08 00 0f 85 74 ff ff ff 48 c7 c7 e8 d1 60 8e c6 05 61 9e 39 08 01 e8 f6 51 55 00 <0f> 0b 5d e9 d9 4f 98 00 80 3d 4b 9e 39 08 00 0f 85 4c ff ff ff 48
[   72.546666] RSP: 0018:ffffb3f841157cf0 EFLAGS: 00010286
[   72.547393] RAX: 0000000000000026 RBX: ffff89ac6231d478 RCX: 0000000000000000
[   72.548324] RDX: ffff89adb7c2c2c0 RSI: ffff89adb7c205c0 RDI: ffff89adb7c205c0
[   72.549271] RBP: ffffb3f841157cf0 R08: 0000000000000000 R09: c0000000ffefffff
[   72.550209] R10: 0000000000000001 R11: ffffb3f841157ad0 R12: ffff89ac6231d180
[   72.551142] R13: ffff89ac6231d478 R14: ffff89ac40c06180 R15: ffff89ac6231d4b0
[   72.552089] FS:  0000000000000000(0000) GS:ffff89adb7c00000(0000) knlGS:0000000000000000
[   72.553175] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   72.553934] CR2: 0000563a310506a8 CR3: 0000000109a66000 CR4: 0000000000350ef0
[   72.554874] Call Trace:
[   72.555278]  <TASK>
[   72.555614]  svc_xprt_put+0xaf/0xe0 [sunrpc]
[   72.556276]  nfsd4_process_cb_update.isra.11+0xb7/0x410 [nfsd]
[   72.557087]  ? update_load_avg+0x82/0x610
[   72.557652]  ? cpuacct_charge+0x60/0x70
[   72.558212]  ? dequeue_entity+0xdb/0x3e0
[   72.558765]  ? queued_spin_unlock+0x9/0x20
[   72.559358]  nfsd4_run_cb_work+0xfc/0x270 [nfsd]
[   72.560031]  process_one_work+0x1df/0x390
[   72.560600]  worker_thread+0x37/0x3b0
[   72.561644]  ? process_one_work+0x390/0x390
[   72.562247]  kthread+0x12f/0x150
[   72.562710]  ? set_kthread_struct+0x50/0x50
[   72.563309]  ret_from_fork+0x22/0x30
[   72.563818]  </TASK>
[   72.564189] ---[ end trace 031117b1c72ec616 ]---
[   72.566019] list_add corruption. next->prev should be prev (ffff89ac4977e538), but was ffff89ac4763e018. (next=ffff89ac4763e018).
[   72.567647] ------------[ cut here ]------------

Fixes: a4abc6b12e ("nfsd: Fix svc_xprt refcnt leak when setup callback client failed")
Cc: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Cc: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Dan Aloni <dan.aloni@vastdata.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-12 09:18:44 -05:00
Jeff Layton
ac3a2585f0 nfsd: rework refcounting in filecache
The filecache refcounting is a bit non-standard for something searchable
by RCU, in that we maintain a sentinel reference while it's hashed. This
in turn requires that we have to do things differently in the "put"
depending on whether its hashed, which we believe to have led to races.

There are other problems in here too. nfsd_file_close_inode_sync can end
up freeing an nfsd_file while there are still outstanding references to
it, and there are a number of subtle ToC/ToU races.

Rework the code so that the refcount is what drives the lifecycle. When
the refcount goes to zero, then unhash and rcu free the object. A task
searching for a nfsd_file is allowed to bump its refcount, but only if
it's not already 0. Ensure that we don't make any other changes to it
until a reference is held.

With this change, the LRU carries a reference. Take special care to deal
with it when removing an entry from the list, and ensure that we only
repurpose the nf_lru list_head when the refcount is 0 to ensure
exclusive access to it.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-11 11:03:09 -05:00
Kees Cook
e78e274eb2 NFSD: Avoid clashing function prototypes
When built with Control Flow Integrity, function prototypes between
caller and function declaration must match. These mismatches are visible
at compile time with the new -Wcast-function-type-strict in Clang[1].

There were 97 warnings produced by NFS. For example:

fs/nfsd/nfs4xdr.c:2228:17: warning: cast from '__be32 (*)(struct nfsd4_compoundargs *, struct nfsd4_access *)' (aka 'unsigned int (*)(struct nfsd4_compoundargs *, struct nfsd4_access *)') to 'nfsd4_dec' (aka 'unsigned int (*)(struct nfsd4_compoundargs *, void *)') converts to incompatible function type [-Wcast-function-type-strict]
        [OP_ACCESS]             = (nfsd4_dec)nfsd4_decode_access,
                                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The enc/dec callbacks were defined as passing "void *" as the second
argument, but were being implicitly cast to a new type. Replace the
argument with union nfsd4_op_u, and perform explicit member selection
in the function body. There are no resulting binary differences.

Changes were made mechanically using the following Coccinelle script,
with minor by-hand fixes for members that didn't already match their
existing argument name:

@find@
identifier func;
type T, opsT;
identifier ops, N;
@@

 opsT ops[] = {
	[N] = (T) func,
 };

@already_void@
identifier find.func;
identifier name;
@@

 func(...,
-void
+union nfsd4_op_u
 *name)
 {
	...
 }

@proto depends on !already_void@
identifier find.func;
type T;
identifier name;
position p;
@@

 func@p(...,
 	T name
 ) {
	...
   }

@script:python get_member@
type_name << proto.T;
member;
@@

coccinelle.member = cocci.make_ident(type_name.split("_", 1)[1].split(' ',1)[0])

@convert@
identifier find.func;
type proto.T;
identifier proto.name;
position proto.p;
identifier get_member.member;
@@

 func@p(...,
-	T name
+	union nfsd4_op_u *u
 ) {
+	T name = &u->member;
	...
   }

@cast@
identifier find.func;
type T, opsT;
identifier ops, N;
@@

 opsT ops[] = {
	[N] =
-	(T)
	func,
 };

Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10 11:01:13 -05:00
Chuck Lever
9315564747 NFSD: Use only RQ_DROPME to signal the need to drop a reply
Clean up: NFSv2 has the only two usages of rpc_drop_reply in the
NFSD code base. Since NFSv2 is going away at some point, replace
these in order to simplify the "drop this reply?" check in
nfsd_dispatch().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-12-10 11:01:13 -05:00
Dai Ngo
638593be55 NFSD: add CB_RECALL_ANY tracepoints
Add tracepoints to trace start and end of CB_RECALL_ANY operation.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
[ cel: added show_rca_mask() macro ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10 11:01:12 -05:00
Dai Ngo
44df6f439a NFSD: add delegation reaper to react to low memory condition
The delegation reaper is called by nfsd memory shrinker's on
the 'count' callback. It scans the client list and sends the
courtesy CB_RECALL_ANY to the clients that hold delegations.

To avoid flooding the clients with CB_RECALL_ANY requests, the
delegation reaper sends only one CB_RECALL_ANY request to each
client per 5 seconds.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
[ cel: moved definition of RCA4_TYPE_MASK_RDATA_DLG ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10 11:01:12 -05:00
Dai Ngo
3959066b69 NFSD: add support for sending CB_RECALL_ANY
Add XDR encode and decode function for CB_RECALL_ANY.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10 11:01:12 -05:00
Dai Ngo
a1049eb47f NFSD: refactoring courtesy_client_reaper to a generic low memory shrinker
Refactoring courtesy_client_reaper to generic low memory
shrinker so it can be used for other purposes.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10 11:01:12 -05:00
Brian Foster
79a1d88a36 NFSD: pass range end to vfs_fsync_range() instead of count
_nfsd_copy_file_range() calls vfs_fsync_range() with an offset and
count (bytes written), but the former wants the start and end bytes
of the range to sync. Fix it up.

Fixes: eac0b17a77 ("NFSD add vfs_fsync after async copy is done")
Signed-off-by: Brian Foster <bfoster@redhat.com>
Tested-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10 11:01:12 -05:00
Xiu Jianfeng
85a0d0c9a5 NFSD: Use struct_size() helper in alloc_session()
Use struct_size() helper to simplify the code, no functional changes.

Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10 11:01:11 -05:00
Jeff Layton
01d53a88c0 nfsd: return error if nfs4_setacl fails
With the addition of POSIX ACLs to struct nfsd_attrs, we no longer
return an error if setting the ACL fails. Ensure we return the na_aclerr
error on SETATTR if there is one.

Fixes: c0cbe70742 ("NFSD: add posix ACLs to struct nfsd_attrs")
Cc: Neil Brown <neilb@suse.de>
Reported-by: Yongcheng Yang <yoyang@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10 11:01:11 -05:00
Chuck Lever
d7064eaf68 NFSD: Add an nfsd_file_fsync tracepoint
Add a tracepoint to capture the number of filecache-triggered fsync
calls and which files needed it. Also, record when an fsync triggers
a write verifier reset.

Examples:

<...>-97    [007]   262.505611: nfsd_file_free:       inode=0xffff888171e08140 ref=0 flags=GC may=WRITE nf_file=0xffff8881373d2400
<...>-97    [007]   262.505612: nfsd_file_fsync:      inode=0xffff888171e08140 ref=0 flags=GC may=WRITE nf_file=0xffff8881373d2400 ret=0
<...>-97    [007]   262.505623: nfsd_file_free:       inode=0xffff888171e08dc0 ref=0 flags=GC may=WRITE nf_file=0xffff8881373d1e00
<...>-97    [007]   262.505624: nfsd_file_fsync:      inode=0xffff888171e08dc0 ref=0 flags=GC may=WRITE nf_file=0xffff8881373d1e00 ret=0

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-12-10 11:00:04 -05:00
Jeff Layton
22ae4c114f nfsd: fix up the filecache laundrette scheduling
We don't really care whether there are hashed entries when it comes to
scheduling the laundrette. They might all be non-gc entries, after all.
We only want to schedule it if there are entries on the LRU.

Switch to using list_lru_count, and move the check into
nfsd_file_gc_worker. The other callsite in nfsd_file_put doesn't need to
count entries, since it only schedules the laundrette after adding an
entry to the LRU.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10 10:59:20 -05:00
Jeff Layton
77c67530e1 nfsd: use locks_inode_context helper
nfsd currently doesn't access i_flctx safely everywhere. This requires a
smp_load_acquire, as the pointer is set via cmpxchg (a release
operation).

Acked-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2022-11-30 05:08:10 -05:00
Jeff Layton
8214118589 nfsd: reorganize filecache.c
In a coming patch, we're going to rework how the filecache refcounting
works. Move some code around in the function to reduce the churn in the
later patches, and rename some of the functions with (hopefully) clearer
names: nfsd_file_flush becomes nfsd_file_fsync, and
nfsd_file_unhash_and_dispose is renamed to nfsd_file_unhash_and_queue.

Also, the nfsd_file_put_final tracepoint is renamed to nfsd_file_free,
to better match the name of the function from which it's called.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-11-28 12:54:48 -05:00
Jeff Layton
1f696e230e nfsd: remove the pages_flushed statistic from filecache
We're counting mapping->nrpages, but not all of those are necessarily
dirty. We don't really have a simple way to count just the dirty pages,
so just remove this stat since it's not accurate.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-11-28 12:54:47 -05:00
Chuck Lever
3f054211b2 NFSD: Fix licensing header in filecache.c
Add a missing SPDX header.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:47 -05:00
Chuck Lever
d47b295e8d NFSD: Use rhashtable for managing nfs4_file objects
fh_match() is costly, especially when filehandles are large (as is
the case for NFSv4). It needs to be used sparingly when searching
data structures. Unfortunately, with common workloads, I see
multiple thousands of objects stored in file_hashtbl[], which has
just 256 buckets, making its bucket hash chains quite lengthy.

Walking long hash chains with the state_lock held blocks other
activity that needs that lock. Sizable hash chains are a common
occurrance once the server has handed out some delegations, for
example -- IIUC, each delegated file is held open on the server by
an nfs4_file object.

To help mitigate the cost of searching with fh_match(), replace the
nfs4_file hash table with an rhashtable, which can dynamically
resize its bucket array to minimize hash chain length.

The result of this modification is an improvement in the latency of
NFSv4 operations, and the reduction of nfsd CPU utilization due to
eliminating the cost of multiple calls to fh_match() and reducing
the CPU cache misses incurred while walking long hash chains in the
nfs4_file hash table.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:47 -05:00
Chuck Lever
1542474800 NFSD: Refactor find_file()
find_file() is now the only caller of find_file_locked(), so just
fold these two together.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:47 -05:00
Chuck Lever
9270fc514b NFSD: Clean up find_or_add_file()
Remove the call to find_file_locked() in insert_nfs4_file(). Tracing
shows that over 99% of these calls return NULL. Thus it is not worth
the expense of the extra bucket list traversal. insert_file() already
deals correctly with the case where the item is already in the hash
bucket.

Since nfsd4_file_hash_insert() is now just a wrapper around
insert_file(), move the meat of insert_file() into
nfsd4_file_hash_insert() and get rid of it.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
2022-11-28 12:54:47 -05:00
Chuck Lever
3341678f2f NFSD: Add a nfsd4_file_hash_remove() helper
Refactor to relocate hash deletion operation to a helper function
that is close to most other nfs4_file data structure operations.

The "noinline" annotation will become useful in a moment when the
hlist_del_rcu() is replaced with a more complex rhash remove
operation. It also guarantees that hash remove operations can be
traced with "-p function -l remove_nfs4_file_locked".

This also simplifies the organization of forward declarations: the
to-be-added rhashtable and its param structure will be defined
/after/ put_nfs4_file().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:47 -05:00
Chuck Lever
81a21fa3e7 NFSD: Clean up nfsd4_init_file()
Name this function more consistently. I'm going to use nfsd4_file_
and nfsd4_file_hash_ for these helpers.

Change the @fh parameter to be const pointer for better type safety.

Finally, move the hash insertion operation to the caller. This is
typical for most other "init_object" type helpers, and it is where
most of the other nfs4_file hash table operations are located.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:46 -05:00
Chuck Lever
3fe828cadd NFSD: Update file_hashtbl() helpers
Enable callers to use const pointers for type safety.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:46 -05:00
Chuck Lever
b48f8056c0 NFSD: Use const pointers as parameters to fh_ helpers
Enable callers to use const pointers where they are able to.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
2022-11-28 12:54:46 -05:00
Chuck Lever
a1c74569bb NFSD: Trace delegation revocations
Delegation revocation is an exceptional event that is not otherwise
visible externally (eg, no network traffic is emitted). Generate a
trace record when it occurs so that revocation can be observed or
other activity can be triggered. Example:

nfsd-1104  [005]  1912.002544: nfsd_stid_revoke:        client 633c9343:4e82788d stateid 00000003:00000001 ref=2 type=DELEG

Trace infrastructure is provided for subsequent additional tracing
related to nfs4_stid activity.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:46 -05:00
Chuck Lever
20eee313ff NFSD: Trace stateids returned via DELEGRETURN
Handing out a delegation stateid is recorded with the
nfsd_deleg_read tracepoint, but there isn't a matching tracepoint
for recording when the stateid is returned.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:46 -05:00
Chuck Lever
eeff73f7c1 NFSD: Clean up nfs4_preprocess_stateid_op() call sites
Remove the lame-duck dprintk()s around nfs4_preprocess_stateid_op()
call sites.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
2022-11-28 12:54:46 -05:00
Chuck Lever
b3276c1f5b NFSD: Flesh out a documenting comment for filecache.c
Record what we've learned recently about the NFSD filecache in a
documenting comment so our future selves don't forget what all this
is for.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:45 -05:00
Chuck Lever
4d1ea84557 NFSD: Add an NFSD_FILE_GC flag to enable nfsd_file garbage collection
NFSv4 operations manage the lifetime of nfsd_file items they use by
means of NFSv4 OPEN and CLOSE. Hence there's no need for them to be
garbage collected.

Introduce a mechanism to enable garbage collection for nfsd_file
items used only by NFSv2/3 callers.

Note that the change in nfsd_file_put() ensures that both CLOSE and
DELEGRETURN will actually close out and free an nfsd_file on last
reference of a non-garbage-collected file.

Link: https://bugzilla.linux-nfs.org/show_bug.cgi?id=394
Suggested-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:45 -05:00
Chuck Lever
dcf3f80965 NFSD: Revert "NFSD: NFSv4 CLOSE should release an nfsd_file immediately"
This reverts commit 5e138c4a75.

That commit attempted to make files available to other users as soon
as all NFSv4 clients were done with them, rather than waiting until
the filecache LRU had garbage collected them.

It gets the reference counting wrong, for one thing.

But it also misses that DELEGRETURN should release a file in the
same fashion. In fact, any nfsd_file_put() on an file held open
by an NFSv4 client needs potentially to release the file
immediately...

Clear the way for implementing that idea.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
2022-11-28 12:54:45 -05:00
Chuck Lever
c252849082 NFSD: Pass the target nfsd_file to nfsd_commit()
In a moment I'm going to introduce separate nfsd_file types, one of
which is garbage-collected; the other, not. The garbage-collected
variety is to be used by NFSv2 and v3, and the non-garbage-collected
variety is to be used by NFSv4.

nfsd_commit() is invoked by both NFSv3 and NFSv4 consumers. We want
nfsd_commit() to find and use the correct variety of cached
nfsd_file object for the NFS version that is in use.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
2022-11-28 12:54:45 -05:00
Jeff Layton
e0aa651068 nfsd: don't call nfsd_file_put from client states seqfile display
We had a report of this:

    BUG: sleeping function called from invalid context at fs/nfsd/filecache.c:440

...with a stack trace showing nfsd_file_put being called from
nfs4_show_open. This code has always tried to call fput while holding a
spinlock, but we recently changed this to use the filecache, and that
started triggering the might_sleep() in nfsd_file_put.

states_start takes and holds the cl_lock while iterating over the
client's states, and we can't sleep with that held.

Have the various nfs4_show_* functions instead hold the fi_lock instead
of taking a nfsd_file reference.

Fixes: 78599c42ae ("nfsd4: add file to display list of client's opens")
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2138357
Reported-by: Zhi Li <yieli@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-11-28 12:54:45 -05:00