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209 Commits (redonkable)

Author SHA1 Message Date
J. Bruce Fields c84138b3c1 nfsd: fix nfsdfs inode reference count leak
[ Upstream commit bf2654017e ]

I don't understand this code well, but  I'm seeing a warning about a
still-referenced inode on unmount, and every other similar filesystem
does a dput() here.

Fixes: e8a79fb14f ("nfsd: add nfsd/clients directory")
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-07-09 09:37:53 +02:00
J. Bruce Fields 2571e17356 nfsd4: fix nfsdfs reference count loop
[ Upstream commit 681370f4b0 ]

We don't drop the reference on the nfsdfs filesystem with
mntput(nn->nfsd_mnt) until nfsd_exit_net(), but that won't be called
until the nfsd module's unloaded, and we can't unload the module as long
as there's a reference on nfsdfs.  So this prevents module unloading.

Fixes: 2c830dd720 ("nfsd: persist nfsd filesystem across mounts")
Reported-and-Tested-by:  Luo Xiaogang <lxgrxd@163.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-07-09 09:37:53 +02:00
J. Bruce Fields 9adcc852d5 nfsd4: make drc_slab global, not per-net
[ Upstream commit 027690c75e ]

I made every global per-network-namespace instead.  But perhaps doing
that to this slab was a step too far.

The kmem_cache_create call in our net init method also seems to be
responsible for this lockdep warning:

[   45.163710] Unable to find swap-space signature
[   45.375718] trinity-c1 (855): attempted to duplicate a private mapping with mremap.  This is not supported.
[   46.055744] futex_wake_op: trinity-c1 tries to shift op by -209; fix this program
[   51.011723]
[   51.013378] ======================================================
[   51.013875] WARNING: possible circular locking dependency detected
[   51.014378] 5.2.0-rc2 #1 Not tainted
[   51.014672] ------------------------------------------------------
[   51.015182] trinity-c2/886 is trying to acquire lock:
[   51.015593] 000000005405f099 (slab_mutex){+.+.}, at: slab_attr_store+0xa2/0x130
[   51.016190]
[   51.016190] but task is already holding lock:
[   51.016652] 00000000ac662005 (kn->count#43){++++}, at: kernfs_fop_write+0x286/0x500
[   51.017266]
[   51.017266] which lock already depends on the new lock.
[   51.017266]
[   51.017909]
[   51.017909] the existing dependency chain (in reverse order) is:
[   51.018497]
[   51.018497] -> #1 (kn->count#43){++++}:
[   51.018956]        __lock_acquire+0x7cf/0x1a20
[   51.019317]        lock_acquire+0x17d/0x390
[   51.019658]        __kernfs_remove+0x892/0xae0
[   51.020020]        kernfs_remove_by_name_ns+0x78/0x110
[   51.020435]        sysfs_remove_link+0x55/0xb0
[   51.020832]        sysfs_slab_add+0xc1/0x3e0
[   51.021332]        __kmem_cache_create+0x155/0x200
[   51.021720]        create_cache+0xf5/0x320
[   51.022054]        kmem_cache_create_usercopy+0x179/0x320
[   51.022486]        kmem_cache_create+0x1a/0x30
[   51.022867]        nfsd_reply_cache_init+0x278/0x560
[   51.023266]        nfsd_init_net+0x20f/0x5e0
[   51.023623]        ops_init+0xcb/0x4b0
[   51.023928]        setup_net+0x2fe/0x670
[   51.024315]        copy_net_ns+0x30a/0x3f0
[   51.024653]        create_new_namespaces+0x3c5/0x820
[   51.025257]        unshare_nsproxy_namespaces+0xd1/0x240
[   51.025881]        ksys_unshare+0x506/0x9c0
[   51.026381]        __x64_sys_unshare+0x3a/0x50
[   51.026937]        do_syscall_64+0x110/0x10b0
[   51.027509]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   51.028175]
[   51.028175] -> #0 (slab_mutex){+.+.}:
[   51.028817]        validate_chain+0x1c51/0x2cc0
[   51.029422]        __lock_acquire+0x7cf/0x1a20
[   51.029947]        lock_acquire+0x17d/0x390
[   51.030438]        __mutex_lock+0x100/0xfa0
[   51.030995]        mutex_lock_nested+0x27/0x30
[   51.031516]        slab_attr_store+0xa2/0x130
[   51.032020]        sysfs_kf_write+0x11d/0x180
[   51.032529]        kernfs_fop_write+0x32a/0x500
[   51.033056]        do_loop_readv_writev+0x21d/0x310
[   51.033627]        do_iter_write+0x2e5/0x380
[   51.034148]        vfs_writev+0x170/0x310
[   51.034616]        do_pwritev+0x13e/0x160
[   51.035100]        __x64_sys_pwritev+0xa3/0x110
[   51.035633]        do_syscall_64+0x110/0x10b0
[   51.036200]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   51.036924]
[   51.036924] other info that might help us debug this:
[   51.036924]
[   51.037876]  Possible unsafe locking scenario:
[   51.037876]
[   51.038556]        CPU0                    CPU1
[   51.039130]        ----                    ----
[   51.039676]   lock(kn->count#43);
[   51.040084]                                lock(slab_mutex);
[   51.040597]                                lock(kn->count#43);
[   51.041062]   lock(slab_mutex);
[   51.041320]
[   51.041320]  *** DEADLOCK ***
[   51.041320]
[   51.041793] 3 locks held by trinity-c2/886:
[   51.042128]  #0: 000000001f55e152 (sb_writers#5){.+.+}, at: vfs_writev+0x2b9/0x310
[   51.042739]  #1: 00000000c7d6c034 (&of->mutex){+.+.}, at: kernfs_fop_write+0x25b/0x500
[   51.043400]  #2: 00000000ac662005 (kn->count#43){++++}, at: kernfs_fop_write+0x286/0x500

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 3ba75830ce "drc containerization"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-24 17:50:37 +02:00
J. Bruce Fields 98a817eda5 nfsd: fsnotify on rmdir under nfsd/clients/
commit 69afd26798 upstream.

Userspace should be able to monitor nfsd/clients/ to see when clients
come and go, but we're failing to send fsnotify events.

Cc: stable@kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-17 10:50:20 +02:00
Linus Torvalds 298fb76a55 Highlights:
- add a new knfsd file cache, so that we don't have to open and
 	  close on each (NFSv2/v3) READ or WRITE.  This can speed up
 	  read and write in some cases.  It also replaces our readahead
 	  cache.
 	- Prevent silent data loss on write errors, by treating write
 	  errors like server reboots for the purposes of write caching,
 	  thus forcing clients to resend their writes.
 	- Tweak the code that allocates sessions to be more forgiving,
 	  so that NFSv4.1 mounts are less likely to hang when a server
 	  already has a lot of clients.
 	- Eliminate an arbitrary limit on NFSv4 ACL sizes; they should
 	  now be limited only by the backend filesystem and the
 	  maximum RPC size.
 	- Allow the server to enforce use of the correct kerberos
 	  credentials when a client reclaims state after a reboot.
 
 And some miscellaneous smaller bugfixes and cleanup.
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Merge tag 'nfsd-5.4' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "Highlights:

   - Add a new knfsd file cache, so that we don't have to open and close
     on each (NFSv2/v3) READ or WRITE. This can speed up read and write
     in some cases. It also replaces our readahead cache.

   - Prevent silent data loss on write errors, by treating write errors
     like server reboots for the purposes of write caching, thus forcing
     clients to resend their writes.

   - Tweak the code that allocates sessions to be more forgiving, so
     that NFSv4.1 mounts are less likely to hang when a server already
     has a lot of clients.

   - Eliminate an arbitrary limit on NFSv4 ACL sizes; they should now be
     limited only by the backend filesystem and the maximum RPC size.

   - Allow the server to enforce use of the correct kerberos credentials
     when a client reclaims state after a reboot.

  And some miscellaneous smaller bugfixes and cleanup"

* tag 'nfsd-5.4' of git://linux-nfs.org/~bfields/linux: (34 commits)
  sunrpc: clean up indentation issue
  nfsd: fix nfs read eof detection
  nfsd: Make nfsd_reset_boot_verifier_locked static
  nfsd: degraded slot-count more gracefully as allocation nears exhaustion.
  nfsd: handle drc over-allocation gracefully.
  nfsd: add support for upcall version 2
  nfsd: add a "GetVersion" upcall for nfsdcld
  nfsd: Reset the boot verifier on all write I/O errors
  nfsd: Don't garbage collect files that might contain write errors
  nfsd: Support the server resetting the boot verifier
  nfsd: nfsd_file cache entries should be per net namespace
  nfsd: eliminate an unnecessary acl size limit
  Deprecate nfsd fault injection
  nfsd: remove duplicated include from filecache.c
  nfsd: Fix the documentation for svcxdr_tmpalloc()
  nfsd: Fix up some unused variable warnings
  nfsd: close cached files prior to a REMOVE or RENAME that would replace target
  nfsd: rip out the raparms cache
  nfsd: have nfsd_test_lock use the nfsd_file cache
  nfsd: hook up nfs4_preprocess_stateid_op to the nfsd_file cache
  ...
2019-09-27 17:00:27 -07:00
Linus Torvalds e170eb2771 Merge branch 'work.mount-base' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs mount API infrastructure updates from Al Viro:
 "Infrastructure bits of mount API conversions.

  The rest is more of per-filesystem updates and that will happen
  in separate pull requests"

* 'work.mount-base' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  mtd: Provide fs_context-aware mount_mtd() replacement
  vfs: Create fs_context-aware mount_bdev() replacement
  new helper: get_tree_keyed()
  vfs: set fs_context::user_ns for reconfigure
2019-09-18 13:15:58 -07:00
Trond Myklebust 27c438f53e nfsd: Support the server resetting the boot verifier
Add support to allow the server to reset the boot verifier in order to
force clients to resend I/O after a timeout failure.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-09-10 09:23:41 -04:00
Al Viro 533770cc0a new helper: get_tree_keyed()
For vfs_get_keyed_super users.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-09-05 14:34:22 -04:00
J. Bruce Fields bebd699716 nfsd: initialize i_private before d_add
A process could race in an open and attempt to read one of these files
before i_private is initialized, and get a spurious error.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-08-15 16:24:07 -04:00
J. Bruce Fields dc46bba709 nfsd: use i_wrlock instead of rcu for nfsdfs i_private
synchronize_rcu() gets called multiple times each time a client is
destroyed.  If the laundromat thread has a lot of clients to destroy,
the delay can be noticeable.  This was causing pynfs test RENEW3 to
fail.

We could embed an rcu_head in each inode and do the kref_put in an rcu
callback.  But simplest is just to take a lock here.

(I also wonder if the laundromat thread would be better replaced by a
bunch of scheduled work or timers or something.)

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-08-15 14:53:02 -04:00
Tetsuo Handa d6846bfbee nfsd: fix dentry leak upon mkdir failure.
syzbot is reporting that nfsd_mkdir() forgot to remove dentry created by
d_alloc_name() when __nfsd_mkdir() failed (due to memory allocation fault
injection) [1].

[1] https://syzkaller.appspot.com/bug?id=ce41a1f769ea4637ebffedf004a803e8405b4674

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+2c95195d5d433f6ed6cb@syzkaller.appspotmail.com>
Fixes: e8a79fb14f ("nfsd: add nfsd/clients directory")
[bfields: clean up in nfsd_mkdir instead of __nfsd_mkdir]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-08-15 14:53:00 -04:00
Linus Torvalds 933a90bf4f Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs mount updates from Al Viro:
 "The first part of mount updates.

  Convert filesystems to use the new mount API"

* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  mnt_init(): call shmem_init() unconditionally
  constify ksys_mount() string arguments
  don't bother with registering rootfs
  init_rootfs(): don't bother with init_ramfs_fs()
  vfs: Convert smackfs to use the new mount API
  vfs: Convert selinuxfs to use the new mount API
  vfs: Convert securityfs to use the new mount API
  vfs: Convert apparmorfs to use the new mount API
  vfs: Convert openpromfs to use the new mount API
  vfs: Convert xenfs to use the new mount API
  vfs: Convert gadgetfs to use the new mount API
  vfs: Convert oprofilefs to use the new mount API
  vfs: Convert ibmasmfs to use the new mount API
  vfs: Convert qib_fs/ipathfs to use the new mount API
  vfs: Convert efivarfs to use the new mount API
  vfs: Convert configfs to use the new mount API
  vfs: Convert binfmt_misc to use the new mount API
  convenience helper: get_tree_single()
  convenience helper get_tree_nodev()
  vfs: Kill sget_userns()
  ...
2019-07-19 10:42:02 -07:00
Linus Torvalds f632a8170a Driver Core and debugfs changes for 5.3-rc1
Here is the "big" driver core and debugfs changes for 5.3-rc1
 
 It's a lot of different patches, all across the tree due to some api
 changes and lots of debugfs cleanups.  Because of this, there is going
 to be some merge issues with your tree at the moment, I'll follow up
 with the expected resolutions to make it easier for you.
 
 Other than the debugfs cleanups, in this set of changes we have:
 	- bus iteration function cleanups (will cause build warnings
 	  with s390 and coresight drivers in your tree)
 	- scripts/get_abi.pl tool to display and parse Documentation/ABI
 	  entries in a simple way
 	- cleanups to Documenatation/ABI/ entries to make them parse
 	  easier due to typos and other minor things
 	- default_attrs use for some ktype users
 	- driver model documentation file conversions to .rst
 	- compressed firmware file loading
 	- deferred probe fixes
 
 All of these have been in linux-next for a while, with a bunch of merge
 issues that Stephen has been patient with me for.  Other than the merge
 issues, functionality is working properly in linux-next :)
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core and debugfs updates from Greg KH:
 "Here is the "big" driver core and debugfs changes for 5.3-rc1

  It's a lot of different patches, all across the tree due to some api
  changes and lots of debugfs cleanups.

  Other than the debugfs cleanups, in this set of changes we have:

   - bus iteration function cleanups

   - scripts/get_abi.pl tool to display and parse Documentation/ABI
     entries in a simple way

   - cleanups to Documenatation/ABI/ entries to make them parse easier
     due to typos and other minor things

   - default_attrs use for some ktype users

   - driver model documentation file conversions to .rst

   - compressed firmware file loading

   - deferred probe fixes

  All of these have been in linux-next for a while, with a bunch of
  merge issues that Stephen has been patient with me for"

* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
  debugfs: make error message a bit more verbose
  orangefs: fix build warning from debugfs cleanup patch
  ubifs: fix build warning after debugfs cleanup patch
  driver: core: Allow subsystems to continue deferring probe
  drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
  arch_topology: Remove error messages on out-of-memory conditions
  lib: notifier-error-inject: no need to check return value of debugfs_create functions
  swiotlb: no need to check return value of debugfs_create functions
  ceph: no need to check return value of debugfs_create functions
  sunrpc: no need to check return value of debugfs_create functions
  ubifs: no need to check return value of debugfs_create functions
  orangefs: no need to check return value of debugfs_create functions
  nfsd: no need to check return value of debugfs_create functions
  lib: 842: no need to check return value of debugfs_create functions
  debugfs: provide pr_fmt() macro
  debugfs: log errors when something goes wrong
  drivers: s390/cio: Fix compilation warning about const qualifiers
  drivers: Add generic helper to match by of_node
  driver_find_device: Unify the match function with class_find_device()
  bus_find_device: Unify the match callback with class_find_device
  ...
2019-07-12 12:24:03 -07:00
YueHaibing b78fa45d4e nfsd: Make __get_nfsdfs_client() static
Fix sparse warning:

fs/nfsd/nfsctl.c:1221:22: warning:
 symbol '__get_nfsdfs_client' was not declared. Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-07-09 19:36:33 -04:00
J. Bruce Fields 97ad4031e2 nfsd4: add a client info file
Add a new nfsd/clients/#/info file with some basic information about
each NFSv4 client.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-07-03 17:52:50 -04:00
J. Bruce Fields bf5ed3e3bb nfsd: make client/ directory names small ints
We want clientid's on the wire to be randomized for reasons explained in
ebd7c72c63 "nfsd: randomize SETCLIENTID reply to help distinguish
servers".  But I'd rather have mostly small integers for the clients/
directory.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-07-03 17:52:50 -04:00
J. Bruce Fields e8a79fb14f nfsd: add nfsd/clients directory
I plan to expose some information about nfsv4 clients here.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-07-03 17:52:49 -04:00
J. Bruce Fields 2c830dd720 nfsd: persist nfsd filesystem across mounts
Keep around one internal mount of the nfsd filesystem so that we can add
stuff to it when clients come and go, regardless of whether anyone has
it mounted.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-07-03 17:52:49 -04:00
J. Bruce Fields 3ba75830ce nfsd4: drc containerization
The nfsd duplicate reply cache should not be shared between network
namespaces.

The most straightforward way to fix this is just to move every global in
the code to per-net-namespace memory, so that's what we do.

Still todo: sort out which members of nfsd_stats should be global and
which per-net-namespace.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-07-03 17:52:08 -04:00
Greg Kroah-Hartman 15b6ff9516 nfsd: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value.  The function can work or not, but the code logic should
never do something different based on this.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190612152603.GB18440@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-03 16:57:17 +02:00
David Howells 96a374a35f vfs: Convert nfsctl to use the new mount API
Convert the nfsctl filesystem to the new internal mount API as the old
one will be obsoleted and removed.  This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.

See Documentation/filesystems/mount_api.txt for more information.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: "J. Bruce Fields" <bfields@fieldses.org>
cc: Jeff Layton <jlayton@kernel.org>
cc: linux-nfs@vger.kernel.org
2019-05-25 17:59:57 -04:00
Thomas Gleixner 09c434b8a0 treewide: Add SPDX license identifier for more missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Trond Myklebust 4df493a260 SUNRPC: Cache the process user cred in the RPC server listener
In order to be able to interpret uids and gids correctly in knfsd, we
should cache the user namespace of the process that created the RPC
server's listener. To do so, we refcount the credential of that process.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-04-24 09:46:35 -04:00
Trond Myklebust e333f3bbef nfsd: Allow containers to set supported nfs versions
Support use of the --nfs-version/--no-nfs-version arguments to rpc.nfsd
in containers.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-04-24 09:46:35 -04:00
Scott Mayhew 362063a595 nfsd: keep a tally of RECLAIM_COMPLETE operations when using nfsdcld
When using nfsdcld for NFSv4 client tracking, track the number of
RECLAIM_COMPLETE operations we receive from "known" clients to help in
deciding if we can lift the grace period early (or whether we need to
start a v4 grace period at all).

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-04-24 09:46:34 -04:00
Linus Torvalds ebc551f2b8 Miscellaneous NFS server fixes. Probably the most visible bug is one
that could artificially limit NFSv4.1 performance by limiting the number
 of oustanding rpcs from a single client.  Neil Brown also gets a special
 mention for fixing a 14.5-year-old memory-corruption bug in the encoding
 of NFSv3 readdir responses.
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Merge tag 'nfsd-5.1' of git://linux-nfs.org/~bfields/linux

Pull NFS server updates from Bruce Fields:
 "Miscellaneous NFS server fixes.

  Probably the most visible bug is one that could artificially limit
  NFSv4.1 performance by limiting the number of oustanding rpcs from a
  single client.

  Neil Brown also gets a special mention for fixing a 14.5-year-old
  memory-corruption bug in the encoding of NFSv3 readdir responses"

* tag 'nfsd-5.1' of git://linux-nfs.org/~bfields/linux:
  nfsd: allow nfsv3 readdir request to be larger.
  nfsd: fix wrong check in write_v4_end_grace()
  nfsd: fix memory corruption caused by readdir
  nfsd: fix performance-limiting session calculation
  svcrpc: fix UDP on servers with lots of threads
  svcrdma: Remove syslog warnings in work completion handlers
  svcrdma: Squelch compiler warning when SUNRPC_DEBUG is disabled
  svcrdma: Use struct_size() in kmalloc()
  svcrpc: fix unlikely races preventing queueing of sockets
  svcrpc: svc_xprt_has_something_to_do seems a little long
  SUNRPC: Don't allow compiler optimisation of svc_xprt_release_slot()
  nfsd: fix an IS_ERR() vs NULL check
2019-03-12 15:06:54 -07:00
Yihao Wu dd838821f0 nfsd: fix wrong check in write_v4_end_grace()
Commit 62a063b8e7 "nfsd4: fix crash on writing v4_end_grace before
nfsd startup" is trying to fix a NULL dereference issue, but it
mistakenly checks if the nfsd server is started. So fix it.

Fixes: 62a063b8e7 "nfsd4: fix crash on writing v4_end_grace before nfsd startup"
Cc: stable@vger.kernel.org
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: Yihao Wu <wuyihao@linux.alibaba.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-03-06 09:58:20 -05:00
J. Bruce Fields 3bf6b57ec2 Revert "nfsd4: return default lease period"
This reverts commit d6ebf5088f.

I forgot that the kernel's default lease period should never be
decreased!

After a kernel upgrade, the kernel has no way of knowing on its own what
the previous lease time was.  Unless userspace tells it otherwise, it
will assume the previous lease period was the same.

So if we decrease this value in a kernel upgrade, we end up enforcing a
grace period that's too short, and clients will fail to reclaim state in
time.  Symptoms may include EIO and log messages like "NFS:
nfs4_reclaim_open_state: Lock reclaim failed!"

There was no real justification for the lease period decrease anyway.

Reported-by: Donald Buczek <buczek@molgen.mpg.de>
Fixes: d6ebf5088f "nfsd4: return default lease period"
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-02-14 12:33:19 -05:00
J. Bruce Fields 62a063b8e7 nfsd4: fix crash on writing v4_end_grace before nfsd startup
Anatoly Trosinenko reports that this:

1) Checkout fresh master Linux branch (tested with commit e195ca6cb)
2) Copy x84_64-config-4.14 to .config, then enable NFS server v4 and build
3) From `kvm-xfstests shell`:

results in NULL dereference in locks_end_grace.

Check that nfsd has been started before trying to end the grace period.

Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-11-28 18:36:02 -05:00
Olga Kornievskaia e0639dc580 NFSD introduce async copy feature
Upon receiving a request for async copy, create a new kthread.  If we
get asynchronous request, make sure to copy the needed arguments/state
from the stack before starting the copy. Then start the thread and reply
back to the client indicating copy is asynchronous.

nfsd_copy_file_range() will copy in a loop over the total number of
bytes is needed to copy. In case a failure happens in the middle, we
ignore the error and return how much we copied so far. Once done
creating a workitem for the callback workqueue and send CB_OFFLOAD with
the results.

The lifetime of the copy stateid is bound to the vfs copy. This way we
don't need to keep the nfsd_net structure for the callback.  We could
keep it around longer so that an OFFLOAD_STATUS that came late would
still get results, but clients should be able to deal without that.

We handle OFFLOAD_CANCEL by sending a signal to the copy thread and
calling kthread_stop.

A client should cancel any ongoing copies before calling DESTROY_CLIENT;
if not, we return a CLIENT_BUSY error.

If the client is destroyed for some other reason (lease expiration, or
server shutdown), we must clean up any ongoing copies ourselves.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
[colin.king@canonical.com: fix leak in error case]
[bfields@fieldses.org: remove signalling, merge patches]
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-09-25 20:34:54 -04:00
Eric Biggers c2cdc2ab24 nfsd: constify write_op[]
write_op[] is never modified, so make it 'const'.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-08-09 16:11:21 -04:00
J. Bruce Fields d6ebf5088f nfsd4: return default lease period
I don't have a good rationale for the lease period, but 90 seconds seems
long, and as long as we're allowing the server to extend the grace
period up to double the lease period, let's half the default to 45.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-06-17 10:20:47 -04:00
J. Bruce Fields 03f318ca65 nfsd4: extend reclaim period for reclaiming clients
If the client is only renewing state a little sooner than once a lease
period, then it might not discover the server has restarted till close
to the end of the grace period, and might run out of time to do the
actual reclaim.

Extend the grace period by a second each time we notice there are
clients still trying to reclaim, up to a limit of another whole lease
period.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-06-17 10:20:47 -04:00
Vasily Averin 2317dc557a race of nfsd inetaddr notifiers vs nn->nfsd_serv change
nfsd_inet[6]addr_event uses nn->nfsd_serv without taking nfsd_mutex,
which can be changed during execution of notifiers and crash the host.

Moreover if notifiers were enabled in one net namespace they are enabled
in all other net namespaces, from creation until destruction.

This patch allows notifiers to access nn->nfsd_serv only after the
pointer is correctly initialized and delays cleanup until notifiers are
no longer in use.

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Tested-by: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-11-27 16:45:11 -05:00
Eric Biggers cda37124f4 fs: constify tree_descr arrays passed to simple_fill_super()
simple_fill_super() is passed an array of tree_descr structures which
describe the files to create in the filesystem's root directory.  Since
these arrays are never modified intentionally, they should be 'const' so
that they are placed in .rodata and benefit from memory protection.
This patch updates the function signature and all users, and also
constifies tree_descr.name.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-04-26 23:54:06 -04:00
NeilBrown abcb4dacb0 NFSD: further refinement of content of /proc/fs/nfsd/versions
Prior to
  e35659f1b0 ("NFSD: correctly range-check v4.x minor version when setting versions.")

v4.0 could not be disabled without disabling all NFSv4 protocols.
So the 'versions' file contained ±4 ±4.1 ±4.2.
Writing "-4" would disable all v4 completely.  Writing +4 would enabled those
minor versions that are currently enabled, either by default or otherwise.

After that commit, it was possible to disable v4.0 independently.  To
maximize backward compatibility with use cases which never disabled
v4.0, the "versions" file would never contain "+4.0" - that was implied
by "+4", unless explicitly negated by "-4.0".

This introduced an inconsistency in that it was possible to disable all
minor versions, but still have the major version advertised.
e.g. "-4.0 -4.1 -4.2 +4" would result in NFSv4 support being advertised,
but all attempts to use it rejected.

Commit
  d3635ff07e ("nfsd: fix configuration of supported minor versions")

and following removed this inconsistency. If all minor version were disabled,
the major would be disabled too.  If any minor was enabled, the major would be
disabled.
This patch also treated "+4" as equivalent to "+4.0" and "-4" as "-4.0".
A consequence of this is that writing "-4" would only disable 4.0.
This is a regression against the earlier behaviour, in a use case that rpc.nfsd
actually uses.
The command "rpc.nfsd -N 4" will write "+2 +3 -4" to the versions files.
Previously, that would disable v4 completely.  Now it will only disable v4.0.

Also "4.0" never appears in the "versions" file when read.
So if only v4.1 is available, the previous kernel would have reported
"+4 -4.0 +4.1 -4.2"  the current kernel reports "-4 +4.1 -4.2" which
could easily confuse.

This patch restores the implication that "+4" and "-4" apply more
globals and do not imply "4.0".
Specifically:
 writing "-4" will disable all 4.x minor versions.
 writing "+4" will enable all 4.1 minor version if none are currently enabled.
    rpc.nfsd will list minor versions before major versions, so
      rpc.nfsd -V 4.2 -N 4.1
    will write "-4.1 +4.2 +2 +3 +4"
    so it would be a regression for "+4" to enable always all versions.
 reading "-4" implies that no v4.x are enabled
 reading "+4" implies that some v4.x are enabled, and that v4.0 is enabled unless
 "-4.0" is also present.  All other minor versions will explicitly be listed.

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-03-10 17:04:50 -05:00
Trond Myklebust ff7d11797e nfsd: Fix display of the version string
The current display code assumes that v4 minor version 0 is tracked by
the call to nfsd_vers(). Now it is tracked by nfsd_minorversion(), and
so we need to adjust the display code.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-27 18:04:17 -05:00
Trond Myklebust d3635ff07e nfsd: fix configuration of supported minor versions
When the user turns off all minor versions of NFSv4, that should be
equivalent to turning off NFSv4 support, so a mount attempt using NFSv4
should get RPC_PROG_MISMATCH, not NFSERR_MINOR_VERS_MISMATCH.

Allow the user to use either '4.0' or '4' to enable or disable minor
version 0.  Other minor versions are still enabled or disabled using the
'4.x' format.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-02-27 18:04:08 -05:00
NeilBrown e35659f1b0 NFSD: correctly range-check v4.x minor version when setting versions.
Writing to /proc/fs/nfsd/versions allows individual major versions
and NFSv4 minor versions to be enabled or disabled.

However NFSv4.0 cannot currently be disabled, thought there is no good reason.
Also the minor number is parsed as a 'long' but used as an 'int'
so '4294967297' will be incorrectly treated as '1'.

This patch removes the test on 'minor == 0' and switches to kstrtouint()
to get correct range checking.

When reading from /proc/fs/nfsd/versions, 4.0 is current not reported.
To allow the disabling for v4.0 to be visible, while maintaining
backward compatibility, change code to report "-4.0" if appropriate, but
not "+4.0".

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-01-31 12:31:53 -05:00
Linus Torvalds 759b2656b2 The one new feature is support for a new NFSv4.2 mode_umask attribute
that makes ACL inheritance a little more useful in environments that
 default to restrictive umasks.  Requires client-side support, also on
 its way for 4.10.
 
 Other than that, miscellaneous smaller fixes and cleanup, especially to
 the server rdma code.
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Merge tag 'nfsd-4.10' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "The one new feature is support for a new NFSv4.2 mode_umask attribute
  that makes ACL inheritance a little more useful in environments that
  default to restrictive umasks. Requires client-side support, also on
  its way for 4.10.

  Other than that, miscellaneous smaller fixes and cleanup, especially
  to the server rdma code"

[ The client side of the umask attribute was merged yesterday ]

* tag 'nfsd-4.10' of git://linux-nfs.org/~bfields/linux:
  nfsd: add support for the umask attribute
  sunrpc: use DEFINE_SPINLOCK()
  svcrdma: Further clean-up of svc_rdma_get_inv_rkey()
  svcrdma: Break up dprintk format in svc_rdma_accept()
  svcrdma: Remove unused variable in rdma_copy_tail()
  svcrdma: Remove unused variables in xprt_rdma_bc_allocate()
  svcrdma: Remove svc_rdma_op_ctxt::wc_status
  svcrdma: Remove DMA map accounting
  svcrdma: Remove BH-disabled spin locking in svc_rdma_send()
  svcrdma: Renovate sendto chunk list parsing
  svcauth_gss: Close connection when dropping an incoming message
  svcrdma: Clear xpt_bc_xps in xprt_setup_rdma_bc() error exit arm
  nfsd: constify reply_cache_stats_operations structure
  nfsd: update workqueue creation
  sunrpc: GFP_KERNEL should be GFP_NOFS in crypto code
  nfsd: catch errors in decode_fattr earlier
  nfsd: clean up supported attribute handling
  nfsd: fix error handling for clients that fail to return the layout
  nfsd: more robust allocation failure handling in nfsd_reply_cache_init
2016-12-16 10:48:28 -08:00
Alexey Dobriyan c7d03a00b5 netns: make struct pernet_operations::id unsigned int
Make struct pernet_operations::id unsigned.

There are 2 reasons to do so:

1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.

2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.

"int" being used as an array index needs to be sign-extended
to 64-bit before being used.

	void f(long *p, int i)
	{
		g(p[i]);
	}

  roughly translates to

	movsx	rsi, esi
	mov	rdi, [rsi+...]
	call 	g

MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.

Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:

	static inline void *net_generic(const struct net *net, int id)
	{
		...
		ptr = ng->ptr[id - 1];
		...
	}

And this function is used a lot, so those sign extensions add up.

Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)

Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]

However, overall balance is in negative direction:

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
	function                                     old     new   delta
	nfsd4_lock                                  3886    3959     +73
	tipc_link_build_proto_msg                   1096    1140     +44
	mac80211_hwsim_new_radio                    2776    2808     +32
	tipc_mon_rcv                                1032    1058     +26
	svcauth_gss_legacy_init                     1413    1429     +16
	tipc_bcbase_select_primary                   379     392     +13
	nfsd4_exchange_id                           1247    1260     +13
	nfsd4_setclientid_confirm                    782     793     +11
		...
	put_client_renew_locked                      494     480     -14
	ip_set_sockfn_get                            730     716     -14
	geneve_sock_add                              829     813     -16
	nfsd4_sequence_done                          721     703     -18
	nlmclnt_lookup_host                          708     686     -22
	nfsd4_lockt                                 1085    1063     -22
	nfs_get_client                              1077    1050     -27
	tcf_bpf_init                                1106    1076     -30
	nfsd4_encode_fattr                          5997    5930     -67
	Total: Before=154856051, After=154854321, chg -0.00%

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18 10:59:15 -05:00
Julia Lawall 7ba630f54c nfsd: constify reply_cache_stats_operations structure
reply_cache_stats_operations, of type struct file_operations, is never
modified, so declare it as const.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Reviewed-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-11-14 15:24:19 -05:00
J. Bruce Fields ebd7c72c63 nfsd: randomize SETCLIENTID reply to help distinguish servers
NFSv4.1 has built-in trunking support that allows a client to determine
whether two connections to two different IP addresses are actually to
the same server.  NFSv4.0 does not, but RFC 7931 attempts to provide
clients a means to do this, basically by performing a SETCLIENTID to one
address and confirming it with a SETCLIENTID_CONFIRM to the other.

Linux clients since 05f4c350ee "NFS: Discover NFSv4 server trunking
when mounting" implement a variation on this suggestion.  It is possible
that other clients do too.

This depends on the clientid and verifier not being accepted by an
unrelated server.  Since both are 64-bit values, that would be very
unlikely if they were random numbers.  But they aren't:

knfsd generates the 64-bit clientid by concatenating the 32-bit boot
time (in seconds) and a counter.  This makes collisions between
clientids generated by the same server extremely unlikely.  But
collisions are very likely between clientids generated by servers that
boot at the same time, and it's quite common for multiple servers to
boot at the same time.  The verifier is a concatenation of the
SETCLIENTID time (in seconds) and a counter, so again collisions between
different servers are likely if multiple SETCLIENTIDs are done at the
same time, which is a common case.

Therefore recent NFSv4.0 clients may decide two different servers are
really the same, and mount a filesystem from the wrong server.

Fortunately the Linux client, since 55b9df93dd "nfsv4/v4.1: Verify the
client owner id during trunking detection", only does this when given
the non-default "migration" mount option.

The fault is really with RFC 7931, and needs a client fix, but in the
meantime we can mitigate the chance of these collisions by randomizing
the starting value of the counters used to generate clientids and
verifiers.

Reported-by: Frank Sorenson <fsorenso@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2016-09-26 15:20:38 -04:00
Linus Torvalds a867d7349e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull userns vfs updates from Eric Biederman:
 "This tree contains some very long awaited work on generalizing the
  user namespace support for mounting filesystems to include filesystems
  with a backing store.  The real world target is fuse but the goal is
  to update the vfs to allow any filesystem to be supported.  This
  patchset is based on a lot of code review and testing to approach that
  goal.

  While looking at what is needed to support the fuse filesystem it
  became clear that there were things like xattrs for security modules
  that needed special treatment.  That the resolution of those concerns
  would not be fuse specific.  That sorting out these general issues
  made most sense at the generic level, where the right people could be
  drawn into the conversation, and the issues could be solved for
  everyone.

  At a high level what this patchset does a couple of simple things:

   - Add a user namespace owner (s_user_ns) to struct super_block.

   - Teach the vfs to handle filesystem uids and gids not mapping into
     to kuids and kgids and being reported as INVALID_UID and
     INVALID_GID in vfs data structures.

  By assigning a user namespace owner filesystems that are mounted with
  only user namespace privilege can be detected.  This allows security
  modules and the like to know which mounts may not be trusted.  This
  also allows the set of uids and gids that are communicated to the
  filesystem to be capped at the set of kuids and kgids that are in the
  owning user namespace of the filesystem.

  One of the crazier corner casees this handles is the case of inodes
  whose i_uid or i_gid are not mapped into the vfs.  Most of the code
  simply doesn't care but it is easy to confuse the inode writeback path
  so no operation that could cause an inode write-back is permitted for
  such inodes (aka only reads are allowed).

  This set of changes starts out by cleaning up the code paths involved
  in user namespace permirted mounts.  Then when things are clean enough
  adds code that cleanly sets s_user_ns.  Then additional restrictions
  are added that are possible now that the filesystem superblock
  contains owner information.

  These changes should not affect anyone in practice, but there are some
  parts of these restrictions that are changes in behavior.

   - Andy's restriction on suid executables that does not honor the
     suid bit when the path is from another mount namespace (think
     /proc/[pid]/fd/) or when the filesystem was mounted by a less
     privileged user.

   - The replacement of the user namespace implicit setting of MNT_NODEV
     with implicitly setting SB_I_NODEV on the filesystem superblock
     instead.

     Using SB_I_NODEV is a stronger form that happens to make this state
     user invisible.  The user visibility can be managed but it caused
     problems when it was introduced from applications reasonably
     expecting mount flags to be what they were set to.

  There is a little bit of work remaining before it is safe to support
  mounting filesystems with backing store in user namespaces, beyond
  what is in this set of changes.

   - Verifying the mounter has permission to read/write the block device
     during mount.

   - Teaching the integrity modules IMA and EVM to handle filesystems
     mounted with only user namespace root and to reduce trust in their
     security xattrs accordingly.

   - Capturing the mounters credentials and using that for permission
     checks in d_automount and the like.  (Given that overlayfs already
     does this, and we need the work in d_automount it make sense to
     generalize this case).

  Furthermore there are a few changes that are on the wishlist:

   - Get all filesystems supporting posix acls using the generic posix
     acls so that posix_acl_fix_xattr_from_user and
     posix_acl_fix_xattr_to_user may be removed.  [Maintainability]

   - Reducing the permission checks in places such as remount to allow
     the superblock owner to perform them.

   - Allowing the superblock owner to chown files with unmapped uids and
     gids to something that is mapped so the files may be treated
     normally.

  I am not considering even obvious relaxations of permission checks
  until it is clear there are no more corner cases that need to be
  locked down and handled generically.

  Many thanks to Seth Forshee who kept this code alive, and putting up
  with me rewriting substantial portions of what he did to handle more
  corner cases, and for his diligent testing and reviewing of my
  changes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (30 commits)
  fs: Call d_automount with the filesystems creds
  fs: Update i_[ug]id_(read|write) to translate relative to s_user_ns
  evm: Translate user/group ids relative to s_user_ns when computing HMAC
  dquot: For now explicitly don't support filesystems outside of init_user_ns
  quota: Handle quota data stored in s_user_ns in quota_setxquota
  quota: Ensure qids map to the filesystem
  vfs: Don't create inodes with a uid or gid unknown to the vfs
  vfs: Don't modify inodes with a uid or gid unknown to the vfs
  cred: Reject inodes with invalid ids in set_create_file_as()
  fs: Check for invalid i_uid in may_follow_link()
  vfs: Verify acls are valid within superblock's s_user_ns.
  userns: Handle -1 in k[ug]id_has_mapping when !CONFIG_USER_NS
  fs: Refuse uid/gid changes which don't map into s_user_ns
  selinux: Add support for unprivileged mounts from user namespaces
  Smack: Handle labels consistently in untrusted mounts
  Smack: Add support for unprivileged mounts from user namespaces
  fs: Treat foreign mounts as nosuid
  fs: Limit file caps to the user namespace of the super block
  userns: Remove the now unnecessary FS_USERNS_DEV_MOUNT flag
  userns: Remove implicit MNT_NODEV fragility.
  ...
2016-07-29 15:54:19 -07:00
Eric W. Biederman d91ee87d8d vfs: Pass data, ns, and ns->userns to mount_ns
Today what is normally called data (the mount options) is not passed
to fill_super through mount_ns.

Pass the mount options and the namespace separately to mount_ns so
that filesystems such as proc that have mount options, can use
mount_ns.

Pass the user namespace to mount_ns so that the standard permission
check that verifies the mounter has permissions over the namespace can
be performed in mount_ns instead of in each filesystems .mount method.
Thus removing the duplication between mqueuefs and proc in terms of
permission checks.  The extra permission check does not currently
affect the rpc_pipefs filesystem and the nfsd filesystem as those
filesystems do not currently allow unprivileged mounts.  Without
unpvileged mounts it is guaranteed that the caller has already passed
capable(CAP_SYS_ADMIN) which guarantees extra permission check will
pass.

Update rpc_pipefs and the nfsd filesystem to ensure that the network
namespace reference is always taken in fill_super and always put in kill_sb
so that the logic is simpler and so that errors originating inside of
fill_super do not cause a network namespace leak.

Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-06-23 15:41:53 -05:00
Al Viro 84c60b1388 drop redundant ->owner initializations
it's not needed for file_operations of inodes located on fs defined
in the hosting module and for file_operations that go into procfs.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-29 19:08:00 -04:00
Giuseppe Cantavenera bb7ffbf29e nfsd: fix nsfd startup race triggering BUG_ON
nfsd triggered a BUG_ON in net_generic(...) when rpc_pipefs_event(...)
in fs/nfsd/nfs4recover.c was called before assigning ntfsd_net_id.
The following was observed on a MIPS 32-core processor:
kernel: Call Trace:
kernel: [<ffffffffc00bc5e4>] rpc_pipefs_event+0x7c/0x158 [nfsd]
kernel: [<ffffffff8017a2a0>] notifier_call_chain+0x70/0xb8
kernel: [<ffffffff8017a4e4>] __blocking_notifier_call_chain+0x4c/0x70
kernel: [<ffffffff8053aff8>] rpc_fill_super+0xf8/0x1a0
kernel: [<ffffffff8022204c>] mount_ns+0xb4/0xf0
kernel: [<ffffffff80222b48>] mount_fs+0x50/0x1f8
kernel: [<ffffffff8023dc00>] vfs_kern_mount+0x58/0xf0
kernel: [<ffffffff802404ac>] do_mount+0x27c/0xa28
kernel: [<ffffffff80240cf0>] SyS_mount+0x98/0xe8
kernel: [<ffffffff80135d24>] handle_sys64+0x44/0x68
kernel:
kernel:
        Code: 0040f809  00000000  2e020001 <00020336> 3c12c00d
                3c02801a  de100000 6442eb98  0040f809
kernel: ---[ end trace 7471374335809536 ]---

Fixed this behaviour by calling register_pernet_subsys(&nfsd_net_ops) before
registering rpc_pipefs_event(...) with the notifier chain.

Signed-off-by: Giuseppe Cantavenera <giuseppe.cantavenera.ext@nokia.com>
Signed-off-by: Lorenzo Restelli <lorenzo.restelli.ext@nokia.com>
Reviewed-by: Kinlong Mee <kinglongmee@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-04-21 16:16:03 -04:00
Christoph Hellwig 9cf514ccfa nfsd: implement pNFS operations
Add support for the GETDEVICEINFO, LAYOUTGET, LAYOUTCOMMIT and
LAYOUTRETURN NFSv4.1 operations, as well as backing code to manage
outstanding layouts and devices.

Layout management is very straight forward, with a nfs4_layout_stateid
structure that extends nfs4_stid to manage layout stateids as the
top-level structure.  It is linked into the nfs4_file and nfs4_client
structures like the other stateids, and contains a linked list of
layouts that hang of the stateid.  The actual layout operations are
implemented in layout drivers that are not part of this commit, but
will be added later.

The worst part of this commit is the management of the pNFS device IDs,
which suffers from a specification that is not sanely implementable due
to the fact that the device-IDs are global and not bound to an export,
and have a small enough size so that we can't store the fsid portion of
a file handle, and must never be reused.  As we still do need perform all
export authentication and validation checks on a device ID passed to
GETDEVICEINFO we are caught between a rock and a hard place.  To work
around this issue we add a new hash that maps from a 64-bit integer to a
fsid so that we can look up the export to authenticate against it,
a 32-bit integer as a generation that we can bump when changing the device,
and a currently unused 32-bit integer that could be used in the future
to handle more than a single device per export.  Entries in this hash
table are never deleted as we can't reuse the ids anyway, and would have
a severe lifetime problem anyway as Linux export structures are temporary
structures that can go away under load.

Parts of the XDR data, structures and marshaling/unmarshaling code, as
well as many concepts are derived from the old pNFS server implementation
from Andy Adamson, Benny Halevy, Dean Hildebrand, Marc Eshel, Fred Isaman,
Mike Sager, Ricardo Labiaga and many others.

Signed-off-by: Christoph Hellwig <hch@lst.de>
2015-02-02 18:09:42 +01:00
Linus Torvalds 0b233b7c79 Merge branch 'for-3.19' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
 "A comparatively quieter cycle for nfsd this time, but still with two
  larger changes:

   - RPC server scalability improvements from Jeff Layton (using RCU
     instead of a spinlock to find idle threads).

   - server-side NFSv4.2 ALLOCATE/DEALLOCATE support from Anna
     Schumaker, enabling fallocate on new clients"

* 'for-3.19' of git://linux-nfs.org/~bfields/linux: (32 commits)
  nfsd4: fix xdr4 count of server in fs_location4
  nfsd4: fix xdr4 inclusion of escaped char
  sunrpc/cache: convert to use string_escape_str()
  sunrpc: only call test_bit once in svc_xprt_received
  fs: nfsd: Fix signedness bug in compare_blob
  sunrpc: add some tracepoints around enqueue and dequeue of svc_xprt
  sunrpc: convert to lockless lookup of queued server threads
  sunrpc: fix potential races in pool_stats collection
  sunrpc: add a rcu_head to svc_rqst and use kfree_rcu to free it
  sunrpc: require svc_create callers to pass in meaningful shutdown routine
  sunrpc: have svc_wake_up only deal with pool 0
  sunrpc: convert sp_task_pending flag to use atomic bitops
  sunrpc: move rq_cachetype field to better optimize space
  sunrpc: move rq_splice_ok flag into rq_flags
  sunrpc: move rq_dropme flag into rq_flags
  sunrpc: move rq_usedeferral flag to rq_flags
  sunrpc: move rq_local field to rq_flags
  sunrpc: add a generic rq_flags field to svc_rqst and move rq_secure to it
  nfsd: minor off by one checks in __write_versions()
  sunrpc: release svc_pool_map reference when serv allocation fails
  ...
2014-12-16 15:25:31 -08:00
Dan Carpenter 818f2f57f2 nfsd: minor off by one checks in __write_versions()
My static checker complains that if "len == remaining" then it means we
have truncated the last character off the version string.

The intent of the code is that we print as many versions as we can
without truncating a version.  Then we put a newline at the end.  If the
newline can't fit we return -EINVAL.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-12-01 12:45:28 -07:00