3395 Commits

Author SHA1 Message Date
Chuck Lever
5f9a62ff7d NFSD: Remove CONFIG_NFSD_V3
Eventually support for NFSv2 in the Linux NFS server is to be
deprecated and then removed.

However, NFSv2 is the "always supported" version that is available
as soon as CONFIG_NFSD is set.  Before NFSv2 support can be removed,
we need to choose a different "always supported" version.

This patch removes CONFIG_NFSD_V3 so that NFSv3 is always supported,
as NFSv2 is today. When NFSv2 support is removed, NFSv3 will become
the only "always supported" NFS version.

The defconfigs still need to be updated to remove CONFIG_NFSD_V3=y.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-03-11 10:25:14 -05:00
Amir Goldstein
4d2eeafecd nfsd: more robust allocation failure handling in nfsd_file_cache_init
The nfsd file cache table can be pretty large and its allocation
may require as many as 80 contigious pages.

Employ the same fix that was employed for similar issue that was
reported for the reply cache hash table allocation several years ago
by commit 8f97514b423a ("nfsd: more robust allocation failure handling
in nfsd_reply_cache_init").

Fixes: 65294c1f2c5e ("nfsd: add a new struct file caching facility to nfsd")
Link: https://lore.kernel.org/linux-nfs/e3cdaeec85a6cfec980e87fc294327c0381c1778.camel@kernel.org/
Suggested-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Amir Goldstein <amir73il@gmail.com>
2022-02-28 10:26:40 -05:00
Chuck Lever
37902c6313 NFSD: Move svc_serv_ops::svo_function into struct svc_serv
Hoist svo_function back into svc_serv and remove struct
svc_serv_ops, since the struct is now devoid of fields.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:40 -05:00
Chuck Lever
f49169c97f NFSD: Remove svc_serv_ops::svo_module
struct svc_serv_ops is about to be removed.

Neil Brown says:
> I suspect svo_module can go as well - I don't think the thread is
> ever the thing that primarily keeps a module active.

A random sample of kthread_create() callers shows sunrpc is the only
one that manages module reference count in this way.

Suggested-by: Neil Brown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:40 -05:00
Chuck Lever
c7d7ec8f04 SUNRPC: Remove svc_shutdown_net()
Clean up: svc_shutdown_net() now does nothing but call
svc_close_net(). Replace all external call sites.

svc_close_net() is renamed to be the inverse of svc_xprt_create().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:40 -05:00
Chuck Lever
4355d767a2 SUNRPC: Rename svc_close_xprt()
Clean up: Use the "svc_xprt_<task>" function naming convention as
is used for other external APIs.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:40 -05:00
Chuck Lever
352ad31448 SUNRPC: Rename svc_create_xprt()
Clean up: Use the "svc_xprt_<task>" function naming convention as
is used for other external APIs.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:39 -05:00
Chuck Lever
87cdd8641c SUNRPC: Remove svo_shutdown method
Clean up. Neil observed that "any code that calls svc_shutdown_net()
knows what the shutdown function should be, and so can call it
directly."

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: NeilBrown <neilb@suse.de>
2022-02-28 10:26:39 -05:00
Chuck Lever
a9ff2e99e9 SUNRPC: Remove the .svo_enqueue_xprt method
We have never been able to track down and address the underlying
cause of the performance issues with workqueue-based service
support. svo_enqueue_xprt is called multiple times per RPC, so
it adds instruction path length, but always ends up at the same
function: svc_xprt_do_enqueue(). We do not anticipate needing
this flexibility for dynamic nfsd thread management support.

As a micro-optimization, remove .svo_enqueue_xprt because
Spectre/Meltdown makes virtual function calls more costly.

This change essentially reverts commit b9e13cdfac70 ("nfsd/sunrpc:
turn enqueueing a svc_xprt into a svc_serv operation").

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:39 -05:00
Chuck Lever
c1a3f2ce66 NFSD: Remove NFSD_PROC_ARGS_* macros
Clean up.

The PROC_ARGS macros were added when I thought that NFSD tracepoints
would be reporting endpoint information. However, tracepoints in the
RPC server now report transport endpoint information, so in general
there's no need for the upper layers to do that any more, and these
macros can be retired.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:39 -05:00
Chuck Lever
9db0e15fb3 NFSD: Use __sockaddr field to store socket addresses
As an example usage of the new __sockaddr field, convert some NFSD
trace points to use it.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:39 -05:00
Chuck Lever
add1511c38 NFSD: Streamline the rare "found" case
Move a rarely called function call site out of the hot path.

This is an exceptionally small improvement because the compiler
inlines most of the functions that nfsd_cache_lookup() calls.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:38 -05:00
Chuck Lever
0f29ce32fb NFSD: Skip extra computation for RC_NOCACHE case
Force the compiler to skip unneeded initialization for cases that
don't need those values. For example, NFSv4 COMPOUND operations are
RC_NOCACHE.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:38 -05:00
Chuck Lever
378a6109dd NFSD: De-duplicate hash bucket indexing
Clean up: The details of finding the right hash bucket are exactly
the same in both nfsd_cache_lookup() and nfsd_cache_update().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:38 -05:00
Ondrej Valousek
e377a3e698 nfsd: Add support for the birth time attribute
For filesystems that supports "btime" timestamp (i.e. most modern
filesystems do) we share it via kernel nfsd. Btime support for NFS
client has already been added by Trond recently.

Suggested-by: Bruce Fields <bfields@fieldses.org>
Signed-off-by: Ondrej Valousek <ondrej.valousek.xm@renesas.com>
[ cel: addressed some whitespace/checkpatch nits ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-28 10:26:38 -05:00
Linus Torvalds
f4bc5bbb5f Notable bug fixes:
Ensure that NFS clients cannot send file size or offset values that
 can cause the NFS server to crash or to return incorrect or
 surprising results. In particular, fix how the NFS server handles
 values larger than OFFSET_MAX.
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Merge tag 'nfsd-5.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull more nfsd fixes from Chuck Lever:
 "Ensure that NFS clients cannot send file size or offset values that
  can cause the NFS server to crash or to return incorrect or surprising
  results.

  In particular, fix how the NFS server handles values larger than
  OFFSET_MAX"

* tag 'nfsd-5.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  NFSD: Deprecate NFS_OFFSET_MAX
  NFSD: Fix offset type in I/O trace points
  NFSD: COMMIT operations must not return NFS?ERR_INVAL
  NFSD: Clamp WRITE offsets
  NFSD: Fix NFSv3 SETATTR/CREATE's handling of large file sizes
  NFSD: Fix ia_size underflow
  NFSD: Fix the behavior of READ near OFFSET_MAX
2022-02-09 09:56:57 -08:00
Chuck Lever
c306d73769 NFSD: Deprecate NFS_OFFSET_MAX
NFS_OFFSET_MAX was introduced way back in Linux v2.3.y before there
was a kernel-wide OFFSET_MAX value. As a clean up, replace the last
few uses of it with its generic equivalent, and get rid of it.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-09 09:24:40 -05:00
Chuck Lever
6a4d333d54 NFSD: Fix offset type in I/O trace points
NFSv3 and NFSv4 use u64 offset values on the wire. Record these values
verbatim without the implicit type case to loff_t.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-09 09:24:30 -05:00
Chuck Lever
3f965021c8 NFSD: COMMIT operations must not return NFS?ERR_INVAL
Since, well, forever, the Linux NFS server's nfsd_commit() function
has returned nfserr_inval when the passed-in byte range arguments
were non-sensical.

However, according to RFC 1813 section 3.3.21, NFSv3 COMMIT requests
are permitted to return only the following non-zero status codes:

      NFS3ERR_IO
      NFS3ERR_STALE
      NFS3ERR_BADHANDLE
      NFS3ERR_SERVERFAULT

NFS3ERR_INVAL is not included in that list. Likewise, NFS4ERR_INVAL
is not listed in the COMMIT row of Table 6 in RFC 8881.

RFC 7530 does permit COMMIT to return NFS4ERR_INVAL, but does not
specify when it can or should be used.

Instead of dropping or failing a COMMIT request in a byte range that
is not supported, turn it into a valid request by treating one or
both arguments as zero. Offset zero means start-of-file, count zero
means until-end-of-file, so we only ever extend the commit range.
NFS servers are always allowed to commit more and sooner than
requested.

The range check is no longer bounded by NFS_OFFSET_MAX, but rather
by the value that is returned in the maxfilesize field of the NFSv3
FSINFO procedure or the NFSv4 maxfilesize file attribute.

Note that this change results in a new pynfs failure:

CMT4     st_commit.testCommitOverflow                             : RUNNING
CMT4     st_commit.testCommitOverflow                             : FAILURE
           COMMIT with offset + count overflow should return
           NFS4ERR_INVAL, instead got NFS4_OK

IMO the test is not correct as written: RFC 8881 does not allow the
COMMIT operation to return NFS4ERR_INVAL.

Reported-by: Dan Aloni <dan.aloni@vastdata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Bruce Fields <bfields@fieldses.org>
2022-02-09 09:24:23 -05:00
Chuck Lever
6260d9a56a NFSD: Clamp WRITE offsets
Ensure that a client cannot specify a WRITE range that falls in a
byte range outside what the kernel's internal types (such as loff_t,
which is signed) can represent. The kiocb iterators, invoked in
nfsd_vfs_write(), should properly limit write operations to within
the underlying file system's s_maxbytes.

Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-09 09:24:01 -05:00
Chuck Lever
a648fdeb7c NFSD: Fix NFSv3 SETATTR/CREATE's handling of large file sizes
iattr::ia_size is a loff_t, so these NFSv3 procedures must be
careful to deal with incoming client size values that are larger
than s64_max without corrupting the value.

Silently capping the value results in storing a different value
than the client passed in which is unexpected behavior, so remove
the min_t() check in decode_sattr3().

Note that RFC 1813 permits only the WRITE procedure to return
NFS3ERR_FBIG. We believe that NFSv3 reference implementations
also return NFS3ERR_FBIG when ia_size is too large.

Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-09 09:23:38 -05:00
Chuck Lever
e6faac3f58 NFSD: Fix ia_size underflow
iattr::ia_size is a loff_t, which is a signed 64-bit type. NFSv3 and
NFSv4 both define file size as an unsigned 64-bit type. Thus there
is a range of valid file size values an NFS client can send that is
already larger than Linux can handle.

Currently decode_fattr4() dumps a full u64 value into ia_size. If
that value happens to be larger than S64_MAX, then ia_size
underflows. I'm about to fix up the NFSv3 behavior as well, so let's
catch the underflow in the common code path: nfsd_setattr().

Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-09 09:22:48 -05:00
Chuck Lever
0cb4d23ae0 NFSD: Fix the behavior of READ near OFFSET_MAX
Dan Aloni reports:
> Due to commit 8cfb9015280d ("NFS: Always provide aligned buffers to
> the RPC read layers") on the client, a read of 0xfff is aligned up
> to server rsize of 0x1000.
>
> As a result, in a test where the server has a file of size
> 0x7fffffffffffffff, and the client tries to read from the offset
> 0x7ffffffffffff000, the read causes loff_t overflow in the server
> and it returns an NFS code of EINVAL to the client. The client as
> a result indefinitely retries the request.

The Linux NFS client does not handle NFS?ERR_INVAL, even though all
NFS specifications permit servers to return that status code for a
READ.

Instead of NFS?ERR_INVAL, have out-of-range READ requests succeed
and return a short result. Set the EOF flag in the result to prevent
the client from retrying the READ request. This behavior appears to
be consistent with Solaris NFS servers.

Note that NFSv3 and NFSv4 use u64 offset values on the wire. These
must be converted to loff_t internally before use -- an implicit
type cast is not adequate for this purpose. Otherwise VFS checks
against sb->s_maxbytes do not work properly.

Reported-by: Dan Aloni <dan.aloni@vastdata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-02-09 09:22:34 -05:00
Linus Torvalds
88808fbbea Notable bug fixes:
- Ensure SM_NOTIFY doesn't crash the NFS server host
 - Ensure NLM locks are cleaned up after client reboot
 - Fix a leak of internal NFSv4 lease information
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Merge tag 'nfsd-5.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd fixes from Chuck Lever:
 "Notable bug fixes:

   - Ensure SM_NOTIFY doesn't crash the NFS server host

   - Ensure NLM locks are cleaned up after client reboot

   - Fix a leak of internal NFSv4 lease information"

* tag 'nfsd-5.17-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  nfsd: nfsd4_setclientid_confirm mistakenly expires confirmed client.
  lockd: fix failure to cleanup client locks
  lockd: fix server crash on reboot of client holding lock
2022-02-02 10:14:31 -08:00
Christoph Hellwig
322cbb50de block: remove genhd.h
There is no good reason to keep genhd.h separate from the main blkdev.h
header that includes it.  So fold the contents of genhd.h into blkdev.h
and remove genhd.h entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220124093913.742411-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-02-02 07:49:59 -07:00
Dai Ngo
ab451ea952 nfsd: nfsd4_setclientid_confirm mistakenly expires confirmed client.
From RFC 7530 Section 16.34.5:

o  The server has not recorded an unconfirmed { v, x, c, *, * } and
   has recorded a confirmed { v, x, c, *, s }.  If the principals of
   the record and of SETCLIENTID_CONFIRM do not match, the server
   returns NFS4ERR_CLID_INUSE without removing any relevant leased
   client state, and without changing recorded callback and
   callback_ident values for client { x }.

The current code intends to do what the spec describes above but
it forgot to set 'old' to NULL resulting to the confirmed client
to be expired.

Fixes: 2b63482185e6 ("nfsd: fix clid_inuse on mount with security change")
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Bruce Fields <bfields@fieldses.org>
2022-01-28 09:04:00 -05:00
Amir Goldstein
29044dae2e fsnotify: fix fsnotify hooks in pseudo filesystems
Commit 49246466a989 ("fsnotify: move fsnotify_nameremove() hook out of
d_delete()") moved the fsnotify delete hook before d_delete() so fsnotify
will have access to a positive dentry.

This allowed a race where opening the deleted file via cached dentry
is now possible after receiving the IN_DELETE event.

To fix the regression in pseudo filesystems, convert d_delete() calls
to d_drop() (see commit 46c46f8df9aa ("devpts_pty_kill(): don't bother
with d_delete()") and move the fsnotify hook after d_drop().

Add a missing fsnotify_unlink() hook in nfsdfs that was found during
the audit of fsnotify hooks in pseudo filesystems.

Note that the fsnotify hooks in simple_recursive_removal() follow
d_invalidate(), so they require no change.

Link: https://lore.kernel.org/r/20220120215305.282577-2-amir73il@gmail.com
Reported-by: Ivan Delalande <colona@arista.com>
Link: https://lore.kernel.org/linux-fsdevel/YeNyzoDM5hP5LtGW@visor/
Fixes: 49246466a989 ("fsnotify: move fsnotify_nameremove() hook out of d_delete()")
Cc: stable@vger.kernel.org # v5.3+
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2022-01-24 14:17:02 +01:00
Linus Torvalds
35ce8ae9ae Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull signal/exit/ptrace updates from Eric Biederman:
 "This set of changes deletes some dead code, makes a lot of cleanups
  which hopefully make the code easier to follow, and fixes bugs found
  along the way.

  The end-game which I have not yet reached yet is for fatal signals
  that generate coredumps to be short-circuit deliverable from
  complete_signal, for force_siginfo_to_task not to require changing
  userspace configured signal delivery state, and for the ptrace stops
  to always happen in locations where we can guarantee on all
  architectures that the all of the registers are saved and available on
  the stack.

  Removal of profile_task_ext, profile_munmap, and profile_handoff_task
  are the big successes for dead code removal this round.

  A bunch of small bug fixes are included, as most of the issues
  reported were small enough that they would not affect bisection so I
  simply added the fixes and did not fold the fixes into the changes
  they were fixing.

  There was a bug that broke coredumps piped to systemd-coredump. I
  dropped the change that caused that bug and replaced it entirely with
  something much more restrained. Unfortunately that required some
  rebasing.

  Some successes after this set of changes: There are few enough calls
  to do_exit to audit in a reasonable amount of time. The lifetime of
  struct kthread now matches the lifetime of struct task, and the
  pointer to struct kthread is no longer stored in set_child_tid. The
  flag SIGNAL_GROUP_COREDUMP is removed. The field group_exit_task is
  removed. Issues where task->exit_code was examined with
  signal->group_exit_code should been examined were fixed.

  There are several loosely related changes included because I am
  cleaning up and if I don't include them they will probably get lost.

  The original postings of these changes can be found at:
     https://lkml.kernel.org/r/87a6ha4zsd.fsf@email.froward.int.ebiederm.org
     https://lkml.kernel.org/r/87bl1kunjj.fsf@email.froward.int.ebiederm.org
     https://lkml.kernel.org/r/87r19opkx1.fsf_-_@email.froward.int.ebiederm.org

  I trimmed back the last set of changes to only the obviously correct
  once. Simply because there was less time for review than I had hoped"

* 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (44 commits)
  ptrace/m68k: Stop open coding ptrace_report_syscall
  ptrace: Remove unused regs argument from ptrace_report_syscall
  ptrace: Remove second setting of PT_SEIZED in ptrace_attach
  taskstats: Cleanup the use of task->exit_code
  exit: Use the correct exit_code in /proc/<pid>/stat
  exit: Fix the exit_code for wait_task_zombie
  exit: Coredumps reach do_group_exit
  exit: Remove profile_handoff_task
  exit: Remove profile_task_exit & profile_munmap
  signal: clean up kernel-doc comments
  signal: Remove the helper signal_group_exit
  signal: Rename group_exit_task group_exec_task
  coredump: Stop setting signal->group_exit_task
  signal: Remove SIGNAL_GROUP_COREDUMP
  signal: During coredumps set SIGNAL_GROUP_EXIT in zap_process
  signal: Make coredump handling explicit in complete_signal
  signal: Have prepare_signal detect coredumps using signal->core_state
  signal: Have the oom killer detect coredumps using signal->core_state
  exit: Move force_uaccess back into do_exit
  exit: Guarantee make_task_dead leaks the tsk when calling do_task_exit
  ...
2022-01-17 05:49:30 +02:00
Linus Torvalds
175398a097 Highlights:
- Bruce steps down as NFSD maintainer
 - Prepare for dynamic nfsd thread management
 - More work on supporting re-exporting NFS mounts
 - One fs/locks patch on behalf of Jeff Layton
 
 Notable bug fixes:
 - Fix zero-length NFSv3 WRITEs
 - Fix directory cinfo on FS's that do not support iversion
 - Fix WRITE verifiers for stable writes
 - Fix crash on COPY_NOTIFY with a special state ID
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Merge tag 'nfsd-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd updates from Chuck Lever:
 "Bruce has announced he is leaving Red Hat at the end of the month and
  is stepping back from his role as NFSD co-maintainer. As a result,
  this includes a patch removing him from the MAINTAINERS file.

  There is one patch in here that Jeff Layton was carrying in the locks
  tree. Since he had only one for this cycle, he asked us to send it to
  you via the nfsd tree.

  There continues to be 0-day reports from Robert Morris @MIT. This time
  we include a fix for a crash in the COPY_NOTIFY operation.

  Highlights:
   - Bruce steps down as NFSD maintainer
   - Prepare for dynamic nfsd thread management
   - More work on supporting re-exporting NFS mounts
   - One fs/locks patch on behalf of Jeff Layton

  Notable bug fixes:
   - Fix zero-length NFSv3 WRITEs
   - Fix directory cinfo on FS's that do not support iversion
   - Fix WRITE verifiers for stable writes
   - Fix crash on COPY_NOTIFY with a special state ID"

* tag 'nfsd-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (51 commits)
  SUNRPC: Fix sockaddr handling in svcsock_accept_class trace points
  SUNRPC: Fix sockaddr handling in the svc_xprt_create_error trace point
  fs/locks: fix fcntl_getlk64/fcntl_setlk64 stub prototypes
  nfsd: fix crash on COPY_NOTIFY with special stateid
  MAINTAINERS: remove bfields
  NFSD: Move fill_pre_wcc() and fill_post_wcc()
  Revert "nfsd: skip some unnecessary stats in the v4 case"
  NFSD: Trace boot verifier resets
  NFSD: Rename boot verifier functions
  NFSD: Clean up the nfsd_net::nfssvc_boot field
  NFSD: Write verifier might go backwards
  nfsd: Add a tracepoint for errors in nfsd4_clone_file_range()
  NFSD: De-duplicate net_generic(nf->nf_net, nfsd_net_id)
  NFSD: De-duplicate net_generic(SVC_NET(rqstp), nfsd_net_id)
  NFSD: Clean up nfsd_vfs_write()
  nfsd: Replace use of rwsem with errseq_t
  NFSD: Fix verifier returned in stable WRITEs
  nfsd: Retry once in nfsd_open on an -EOPENSTALE return
  nfsd: Add errno mapping for EREMOTEIO
  nfsd: map EBADF
  ...
2022-01-16 07:42:58 +02:00
Linus Torvalds
5dfbfe71e3 fs.idmapped.v5.17
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Merge tag 'fs.idmapped.v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux

Pull fs idmapping updates from Christian Brauner:
 "This contains the work to enable the idmapping infrastructure to
  support idmapped mounts of filesystems mounted with an idmapping.

  In addition this contains various cleanups that avoid repeated
  open-coding of the same functionality and simplify the code in quite a
  few places.

  We also finish the renaming of the mapping helpers we started a few
  kernel releases back and move them to a dedicated header to not
  continue polluting the fs header needlessly with low-level idmapping
  helpers. With this series the fs header only contains idmapping
  helpers that interact with fs objects.

  Currently we only support idmapped mounts for filesystems mounted
  without an idmapping themselves. This was a conscious decision
  mentioned in multiple places (cf. [1]).

  As explained at length in [3] it is perfectly fine to extend support
  for idmapped mounts to filesystem's mounted with an idmapping should
  the need arise. The need has been there for some time now (cf. [2]).

  Before we can port any filesystem that is mountable with an idmapping
  to support idmapped mounts in the coming cycles, we need to first
  extend the mapping helpers to account for the filesystem's idmapping.
  This again, is explained at length in our documentation at [3] and
  also in the individual commit messages so here's an overview.

  Currently, the low-level mapping helpers implement the remapping
  algorithms described in [3] in a simplified manner as we could rely on
  the fact that all filesystems supporting idmapped mounts are mounted
  without an idmapping.

  In contrast, filesystems mounted with an idmapping are very likely to
  not use an identity mapping and will instead use a non-identity
  mapping. So the translation step from or into the filesystem's
  idmapping in the remapping algorithm cannot be skipped for such
  filesystems.

  Non-idmapped filesystems and filesystems not supporting idmapped
  mounts are unaffected by this change as the remapping algorithms can
  take the same shortcut as before. If the low-level helpers detect that
  they are dealing with an idmapped mount but the underlying filesystem
  is mounted without an idmapping we can rely on the previous shortcut
  and can continue to skip the translation step from or into the
  filesystem's idmapping. And of course, if the low-level helpers detect
  that they are not dealing with an idmapped mount they can simply
  return the relevant id unchanged; no remapping needs to be performed
  at all.

  These checks guarantee that only the minimal amount of work is
  performed. As before, if idmapped mounts aren't used the low-level
  helpers are idempotent and no work is performed at all"

Link: 2ca4dcc4909d ("fs/mount_setattr: tighten permission checks") [1]
Link: https://github.com/containers/podman/issues/10374 [2]
Link: Documentations/filesystems/idmappings.rst [3]
Link: a65e58e791a1 ("fs: document and rename fsid helpers") [4]

* tag 'fs.idmapped.v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
  fs: support mapped mounts of mapped filesystems
  fs: add i_user_ns() helper
  fs: port higher-level mapping helpers
  fs: remove unused low-level mapping helpers
  fs: use low-level mapping helpers
  docs: update mapping documentation
  fs: account for filesystem mappings
  fs: tweak fsuidgid_has_mapping()
  fs: move mapping helpers
  fs: add is_idmapped_mnt() helper
2022-01-11 14:26:55 -08:00
J. Bruce Fields
074b07d94e nfsd: fix crash on COPY_NOTIFY with special stateid
RTM says "If the special ONE stateid is passed to
nfs4_preprocess_stateid_op(), it returns status=0 but does not set
*cstid. nfsd4_copy_notify() depends on stid being set if status=0, and
thus can crash if the client sends the right COPY_NOTIFY RPC."

RFC 7862 says "The cna_src_stateid MUST refer to either open or locking
states provided earlier by the server.  If it is invalid, then the
operation MUST fail."

The RFC doesn't specify an error, and the choice doesn't matter much as
this is clearly illegal client behavior, but bad_stateid seems
reasonable.

Simplest is just to guarantee that nfs4_preprocess_stateid_op, called
with non-NULL cstid, errors out if it can't return a stateid.

Reported-by: rtm@csail.mit.edu
Fixes: 624322f1adc5 ("NFSD add COPY_NOTIFY operation")
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Olga Kornievskaia <kolga@netapp.com>
Tested-by: Olga Kornievskaia <kolga@netapp.com>
2022-01-08 14:42:03 -05:00
Chuck Lever
fcb5e3fa01 NFSD: Move fill_pre_wcc() and fill_post_wcc()
These functions are related to file handle processing and have
nothing to do with XDR encoding or decoding. Also they are no longer
NFSv3-specific. As a clean-up, move their definitions to a more
appropriate location. WCC is also an NFSv3-specific term, so rename
them as general-purpose helpers.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:03 -05:00
Chuck Lever
58f258f652 Revert "nfsd: skip some unnecessary stats in the v4 case"
On the wire, I observed NFSv4 OPEN(CREATE) operations sometimes
returning a reasonable-looking value in the cinfo.before field and
zero in the cinfo.after field.

RFC 8881 Section 10.8.1 says:
> When a client is making changes to a given directory, it needs to
> determine whether there have been changes made to the directory by
> other clients.  It does this by using the change attribute as
> reported before and after the directory operation in the associated
> change_info4 value returned for the operation.

and

> ... The post-operation change
> value needs to be saved as the basis for future change_info4
> comparisons.

A good quality client implementation therefore saves the zero
cinfo.after value. During a subsequent OPEN operation, it will
receive a different non-zero value in the cinfo.before field for
that directory, and it will incorrectly believe the directory has
changed, triggering an undesirable directory cache invalidation.

There are filesystem types where fs_supports_change_attribute()
returns false, tmpfs being one. On NFSv4 mounts, this means the
fh_getattr() call site in fill_pre_wcc() and fill_post_wcc() is
never invoked. Subsequently, nfsd4_change_attribute() is invoked
with an uninitialized @stat argument.

In fill_pre_wcc(), @stat contains stale stack garbage, which is
then placed on the wire. In fill_post_wcc(), ->fh_post_wc is all
zeroes, so zero is placed on the wire. Both of these values are
meaningless.

This fix can be applied immediately to stable kernels. Once there
are more regression tests in this area, this optimization can be
attempted again.

Fixes: 428a23d2bf0c ("nfsd: skip some unnecessary stats in the v4 case")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:03 -05:00
Chuck Lever
75acacb658 NFSD: Trace boot verifier resets
According to commit bbf2f098838a ("nfsd: Reset the boot verifier on
all write I/O errors"), the Linux NFS server forces all clients to
resend pending unstable writes if any server-side write or commit
operation encounters an error (say, ENOSPC). This is a rare and
quite exceptional event that could require administrative recovery
action, so it should be made trace-able. Example trace event:

nfsd-938   [002]  7174.945558: nfsd_writeverf_reset: boot_time=        61cc920d xid=0xdcd62036 error=-28 new verifier=0x08aecc6142515904

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:03 -05:00
Chuck Lever
3988a57885 NFSD: Rename boot verifier functions
Clean up: These functions handle what the specs call a write
verifier, which in the Linux NFS server implementation is now
divorced from the server's boot instance

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:02 -05:00
Chuck Lever
91d2e9b56c NFSD: Clean up the nfsd_net::nfssvc_boot field
There are two boot-time fields in struct nfsd_net: one called
boot_time and one called nfssvc_boot. The latter is used only to
form write verifiers, but its documenting comment declares:

        /* Time of server startup */

Since commit 27c438f53e79 ("nfsd: Support the server resetting the
boot verifier"), this field can be reset at any time; it's no
longer tied to server restart. So that comment is stale.

Also, according to pahole, struct timespec64 is 16 bytes long on
x86_64. The nfssvc_boot field is used only to form a write verifier,
which is 8 bytes long.

Let's clarify this situation by manufacturing an 8-byte verifier
in nfs_reset_boot_verifier() and storing only that in struct
nfsd_net.

We're grabbing 128 bits of time, so compress all of those into a
64-bit verifier instead of throwing out the high-order bits.
In the future, the siphash_key can be re-used for other hashed
objects per-nfsd_net.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:02 -05:00
Chuck Lever
cdc556600c NFSD: Write verifier might go backwards
When vfs_iter_write() starts to fail because a file system is full,
a bunch of writes can fail at once with ENOSPC. These writes
repeatedly invoke nfsd_reset_boot_verifier() in quick succession.

Ensure that the time it grabs doesn't go backwards due to an ntp
adjustment going on at the same time.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:02 -05:00
Trond Myklebust
a2f4c3fa4d nfsd: Add a tracepoint for errors in nfsd4_clone_file_range()
Since a clone error commit can cause the boot verifier to change,
we should trace those errors.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[ cel: Addressed a checkpatch.pl splat in fs/nfsd/vfs.h ]
2022-01-08 14:42:02 -05:00
Chuck Lever
2c445a0e72 NFSD: De-duplicate net_generic(nf->nf_net, nfsd_net_id)
Since this pointer is used repeatedly, move it to a stack variable.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:02 -05:00
Chuck Lever
fb7622c2db NFSD: De-duplicate net_generic(SVC_NET(rqstp), nfsd_net_id)
Since this pointer is used repeatedly, move it to a stack variable.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:02 -05:00
Chuck Lever
33388b3aef NFSD: Clean up nfsd_vfs_write()
The RWF_SYNC and !RWF_SYNC arms are now exactly alike except that
the RWF_SYNC arm resets the boot verifier twice in a row. Fix that
redundancy and de-duplicate the code.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:02 -05:00
Trond Myklebust
555dbf1a9a nfsd: Replace use of rwsem with errseq_t
The nfsd_file nf_rwsem is currently being used to separate file write
and commit instances to ensure that we catch errors and apply them to
the correct write/commit.
We can improve scalability at the expense of a little accuracy (some
extra false positives) by replacing the nf_rwsem with more careful
use of the errseq_t mechanism to track errors across the different
operations.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[ cel: rebased on zero-verifier fix ]
2022-01-08 14:42:02 -05:00
Chuck Lever
f11ad7aa65 NFSD: Fix verifier returned in stable WRITEs
RFC 8881 explains the purpose of the write verifier this way:

> The final portion of the result is the field writeverf. This field
> is the write verifier and is a cookie that the client can use to
> determine whether a server has changed instance state (e.g., server
> restart) between a call to WRITE and a subsequent call to either
> WRITE or COMMIT.

But then it says:

> This cookie MUST be unchanged during a single instance of the
> NFSv4.1 server and MUST be unique between instances of the NFSv4.1
> server. If the cookie changes, then the client MUST assume that
> any data written with an UNSTABLE4 value for committed and an old
> writeverf in the reply has been lost and will need to be
> recovered.

RFC 1813 has similar language for NFSv3. NFSv2 does not have a write
verifier since it doesn't implement the COMMIT procedure.

Since commit 19e0663ff9bc ("nfsd: Ensure sampling of the write
verifier is atomic with the write"), the Linux NFS server has
returned a boot-time-based verifier for UNSTABLE WRITEs, but a zero
verifier for FILE_SYNC and DATA_SYNC WRITEs. FILE_SYNC and DATA_SYNC
WRITEs are not followed up with a COMMIT, so there's no need for
clients to compare verifiers for stable writes.

However, by returning a different verifier for stable and unstable
writes, the above commit puts the Linux NFS server a step farther
out of compliance with the first MUST above. At least one NFS client
(FreeBSD) noticed the difference, making this a potential
regression.

Reported-by: Rick Macklem <rmacklem@uoguelph.ca>
Link: https://lore.kernel.org/linux-nfs/YQXPR0101MB096857EEACF04A6DF1FC6D9BDD749@YQXPR0101MB0968.CANPRD01.PROD.OUTLOOK.COM/T/
Fixes: 19e0663ff9bc ("nfsd: Ensure sampling of the write verifier is atomic with the write")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:02 -05:00
Jeff Layton
12bcbd40fd nfsd: Retry once in nfsd_open on an -EOPENSTALE return
If we get back -EOPENSTALE from an NFSv4 open, then we either got some
unhandled error or the inode we got back was not the same as the one
associated with the dentry.

We really have no recourse in that situation other than to retry the
open, and if it fails to just return nfserr_stale back to the client.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:02 -05:00
Jeff Layton
a2694e51f6 nfsd: Add errno mapping for EREMOTEIO
The NFS client can occasionally return EREMOTEIO when signalling issues
with the server.  ...map to NFSERR_IO.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:01 -05:00
Peng Tao
b3d0db706c nfsd: map EBADF
Now that we have open file cache, it is possible that another client
deletes the file and DP will not know about it. Then IO to MDS would
fail with BADSTATEID and knfsd would start state recovery, which
should fail as well and then nfs read/write will fail with EBADF.
And it triggers a WARN() in nfserrno().

-----------[ cut here ]------------
WARNING: CPU: 0 PID: 13529 at fs/nfsd/nfsproc.c:758 nfserrno+0x58/0x70 [nfsd]()
nfsd: non-standard errno: -9
modules linked in: nfsv3 nfs_layout_flexfiles rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_connt
pata_acpi floppy
CPU: 0 PID: 13529 Comm: nfsd Tainted: G        W       4.1.5-00307-g6e6579b #7
Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 09/30/2014
 0000000000000000 00000000464e6c9c ffff88079085fba8 ffffffff81789936
 0000000000000000 ffff88079085fc00 ffff88079085fbe8 ffffffff810a08ea
 ffff88079085fbe8 ffff88080f45c900 ffff88080f627d50 ffff880790c46a48
 all Trace:
 [<ffffffff81789936>] dump_stack+0x45/0x57
 [<ffffffff810a08ea>] warn_slowpath_common+0x8a/0xc0
 [<ffffffff810a0975>] warn_slowpath_fmt+0x55/0x70
 [<ffffffff81252908>] ? splice_direct_to_actor+0x148/0x230
 [<ffffffffa02fb8c0>] ? fsid_source+0x60/0x60 [nfsd]
 [<ffffffffa02f9918>] nfserrno+0x58/0x70 [nfsd]
 [<ffffffffa02fba57>] nfsd_finish_read+0x97/0xb0 [nfsd]
 [<ffffffffa02fc7a6>] nfsd_splice_read+0x76/0xa0 [nfsd]
 [<ffffffffa02fcca1>] nfsd_read+0xc1/0xd0 [nfsd]
 [<ffffffffa0233af2>] ? svc_tcp_adjust_wspace+0x12/0x30 [sunrpc]
 [<ffffffffa03073da>] nfsd3_proc_read+0xba/0x150 [nfsd]
 [<ffffffffa02f7a03>] nfsd_dispatch+0xc3/0x210 [nfsd]
 [<ffffffffa0233af2>] ? svc_tcp_adjust_wspace+0x12/0x30 [sunrpc]
 [<ffffffffa0232913>] svc_process_common+0x453/0x6f0 [sunrpc]
 [<ffffffffa0232cc3>] svc_process+0x113/0x1b0 [sunrpc]
 [<ffffffffa02f740f>] nfsd+0xff/0x170 [nfsd]
 [<ffffffffa02f7310>] ? nfsd_destroy+0x80/0x80 [nfsd]
 [<ffffffff810bf3a8>] kthread+0xd8/0xf0
 [<ffffffff810bf2d0>] ? kthread_create_on_node+0x1b0/0x1b0
 [<ffffffff817912a2>] ret_from_fork+0x42/0x70
 [<ffffffff810bf2d0>] ? kthread_create_on_node+0x1b0/0x1b0

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:01 -05:00
Chuck Lever
6a2f774424 NFSD: Fix zero-length NFSv3 WRITEs
The Linux NFS server currently responds to a zero-length NFSv3 WRITE
request with NFS3ERR_IO. It responds to a zero-length NFSv4 WRITE
with NFS4_OK and count of zero.

RFC 1813 says of the WRITE procedure's @count argument:

count
         The number of bytes of data to be written. If count is
         0, the WRITE will succeed and return a count of 0,
         barring errors due to permissions checking.

RFC 8881 has similar language for NFSv4, though NFSv4 removed the
explicit @count argument because that value is already contained in
the opaque payload array.

The synthetic client pynfs's WRT4 and WRT15 tests do emit zero-
length WRITEs to exercise this spec requirement. Commit fdec6114ee1f
("nfsd4: zero-length WRITE should succeed") addressed the same
problem there with the same fix.

But interestingly the Linux NFS client does not appear to emit zero-
length WRITEs, instead squelching them. I'm not aware of a test that
can generate such WRITEs for NFSv3, so I wrote a naive C program to
generate a zero-length WRITE and test this fix.

Fixes: 8154ef2776aa ("NFSD: Clean up legacy NFS WRITE argument XDR decoders")
Reported-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:01 -05:00
Vasily Averin
47446d74f1 nfsd4: add refcount for nfsd4_blocked_lock
nbl allocated in nfsd4_lock can be released by a several ways:
directly in nfsd4_lock(), via nfs4_laundromat(), via another nfs
command RELEASE_LOCKOWNER or via nfsd4_callback.
This structure should be refcounted to be used and released correctly
in all these cases.

Refcount is initialized to 1 during allocation and is incremented
when nbl is added into nbl_list/nbl_lru lists.

Usually nbl is linked into both lists together, so only one refcount
is used for both lists.

However nfsd4_lock() should keep in mind that nbl can be present
in one of lists only. This can happen if nbl was handled already
by nfs4_laundromat/nfsd4_callback/etc.

Refcount is decremented if vfs_lock_file() returns FILE_LOCK_DEFERRED,
because nbl can be handled already by nfs4_laundromat/nfsd4_callback/etc.

Refcount is not changed in find_blocked_lock() because of it reuses counter
released after removing nbl from lists.

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:01 -05:00
J. Bruce Fields
40595cdc93 nfs: block notification on fs with its own ->lock
NFSv4.1 supports an optional lock notification feature which notifies
the client when a lock comes available.  (Normally NFSv4 clients just
poll for locks if necessary.)  To make that work, we need to request a
blocking lock from the filesystem.

We turned that off for NFS in commit f657f8eef3ff ("nfs: don't atempt
blocking locks on nfs reexports") [sic] because it actually blocks the
nfsd thread while waiting for the lock.

Thanks to Vasily Averin for pointing out that NFS isn't the only
filesystem with that problem.

Any filesystem that leaves ->lock NULL will use posix_lock_file(), which
does the right thing.  Simplest is just to assume that any filesystem
that defines its own ->lock is not safe to request a blocking lock from.

So, this patch mostly reverts commit f657f8eef3ff ("nfs: don't atempt
blocking locks on nfs reexports") [sic] and commit b840be2f00c0 ("lockd:
don't attempt blocking locks on nfs reexports"), and instead uses a
check of ->lock (Vasily's suggestion) to decide whether to support
blocking lock notifications on a given filesystem.  Also add a little
documentation.

Perhaps someday we could add back an export flag later to allow
filesystems with "good" ->lock methods to support blocking lock
notifications.

Reported-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
[ cel: Description rewritten to address checkpatch nits ]
[ cel: Fixed warning when SUNRPC debugging is disabled ]
[ cel: Fixed NULL check ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Vasily Averin <vvs@virtuozzo.com>
2022-01-08 14:42:01 -05:00
Chuck Lever
cd2e999c7c NFSD: De-duplicate nfsd4_decode_bitmap4()
Clean up. Trond points out that xdr_stream_decode_uint32_array()
does the same thing as nfsd4_decode_bitmap4().

Suggested-by: Trond Myklebust <trondmy@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-01-08 14:42:01 -05:00