Граф коммитов

376 Коммитов

Автор SHA1 Сообщение Дата
Andi Kleen f2f2494c8a Add process name and pid to locks warning
It's fairly useless to complain about using an obsolete feature without
telling the user which process used it. My Fedora desktop randomly drops
this message, but I would really need this patch to figure out what
triggers is.

[ jlayton: print pid as well as process name ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2022-11-30 05:08:10 -05:00
Jeff Layton 401a8b8fd5 filelock: add a new locks_inode_context accessor function
There are a number of places in the kernel that are accessing the
inode->i_flctx field without smp_load_acquire. This is required to
ensure that the caller doesn't see a partially-initialized structure.

Add a new accessor function for it to make this clear and convert all of
the relevant accesses in locks.c to use it. Also, convert
locks_free_lock_context to use the helper as well instead of just doing
a "bare" assignment.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2022-11-30 05:08:10 -05:00
Jeff Layton ab1ddef98a filelock: new helper: vfs_inode_has_locks
Ceph has a need to know whether a particular inode has any locks set on
it. It's currently tracking that by a num_locks field in its
filp->private_data, but that's problematic as it tries to decrement this
field when releasing locks and that can race with the file being torn
down.

Add a new vfs_inode_has_locks helper that just returns whether any locks
are currently held on the inode.

Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2022-11-30 05:06:06 -05:00
Jeff Layton 7e8e5cc818 filelock: WARN_ON_ONCE when ->fl_file and filp don't match
vfs_lock_file, vfs_test_lock and vfs_cancel_lock all take both a struct
file argument and a file_lock. The file_lock has a fl_file field in it
howevever and it _must_ match the file passed in.

While most of the locks.c routines use the separately-passed file
argument, some filesystems rely on fl_file being filled out correctly.

I'm working on a patch series to remove the redundant argument from
these routines, but for now, let's ensure that the callers always set
this properly by issuing a WARN_ON_ONCE if they ever don't match.

Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Trond Myklebust <trondmy@hammerspace.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2022-11-17 05:21:00 -05:00
David Howells 932c29a10d locks: Fix dropped call to ->fl_release_private()
Prior to commit 4149be7bda, sys_flock() would allocate the file_lock
struct it was going to use to pass parameters, call ->flock() and then call
locks_free_lock() to get rid of it - which had the side effect of calling
locks_release_private() and thus ->fl_release_private().

With commit 4149be7bda, however, this is no longer the case: the struct
is now allocated on the stack, and locks_free_lock() is no longer called -
and thus any remaining private data doesn't get cleaned up either.

This causes afs flock to cause oops.  Kasan catches this as a UAF by the
list_del_init() in afs_fl_release_private() for the file_lock record
produced by afs_fl_copy_lock() as the original record didn't get delisted.
It can be reproduced using the generic/504 xfstest.

Fix this by reinstating the locks_release_private() call in sys_flock().
I'm not sure if this would affect any other filesystems.  If not, then the
release could be done in afs_flock() instead.

Changes
=======
ver #2)
 - Don't need to call ->fl_release_private() after calling the security
   hook, only after calling ->flock().

Fixes: 4149be7bda ("fs/lock: Don't allocate file_lock in flock_make_lock().")
cc: Chuck Lever <chuck.lever@oracle.com>
cc: Jeff Layton <jlayton@kernel.org>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
cc: linux-fsdevel@vger.kernel.org
Link: https://lore.kernel.org/r/166075758809.3532462.13307935588777587536.stgit@warthog.procyon.org.uk/ # v1
Acked-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2022-08-17 15:08:58 -04:00
Kuniyuki Iwashima db4abb4a32 fs/lock: Rearrange ops in flock syscall.
The previous patch added flock_translate_cmd() in flock syscall.
The test and the other one for LOCK_MAND do not depend on struct
fd and are cheaper, so we can put them at the top and defer
fdget() after that.

Also, we can remove the unlock variable and use type instead.
While at it, we fix this checkpatch error.

  CHECK: spaces preferred around that '|' (ctx:VxV)
  #45: FILE: fs/locks.c:2099:
  +	if (type != F_UNLCK && !(f.file->f_mode & (FMODE_READ|FMODE_WRITE)))
   	                                                     ^

Finally, we can move the can_sleep part just before we use it.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2022-07-18 10:01:47 -04:00
Kuniyuki Iwashima 4149be7bda fs/lock: Don't allocate file_lock in flock_make_lock().
Two functions, flock syscall and locks_remove_flock(), call
flock_make_lock().  It allocates struct file_lock from slab
cache if its argument fl is NULL.

When we call flock syscall, we pass NULL to allocate memory
for struct file_lock.  However, we always free it at the end
by locks_free_lock().  We need not allocate it and instead
should use a local variable as locks_remove_flock() does.

Also, the validation for flock_translate_cmd() is not necessary
for locks_remove_flock().  So we move the part to flock syscall
and make flock_make_lock() return nothing.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2022-07-18 10:01:41 -04:00
Dai Ngo 2443da2259 fs/lock: add 2 callbacks to lock_manager_operations to resolve conflict
Add 2 new callbacks, lm_lock_expirable and lm_expire_lock, to
lock_manager_operations to allow the lock manager to take appropriate
action to resolve the lock conflict if possible.

A new field, lm_mod_owner, is also added to lock_manager_operations.
The lm_mod_owner is used by the fs/lock code to make sure the lock
manager module such as nfsd, is not freed while lock conflict is being
resolved.

lm_lock_expirable checks and returns true to indicate that the lock
conflict can be resolved else return false. This callback must be
called with the flc_lock held so it can not block.

lm_expire_lock is called to resolve the lock conflict if the returned
value from lm_lock_expirable is true. This callback is called without
the flc_lock held since it's allowed to block. Upon returning from
this callback, the lock conflict should be resolved and the caller is
expected to restart the conflict check from the beginnning of the list.

Lock manager, such as NFSv4 courteous server, uses this callback to
resolve conflict by destroying lock owner, or the NFSv4 courtesy client
(client that has expired but allowed to maintains its states) that owns
the lock.

Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-05-19 12:25:39 -04:00
Dai Ngo 591502c5cb fs/lock: add helper locks_owner_has_blockers to check for blockers
Add helper locks_owner_has_blockers to check if there is any blockers
for a given lockowner.

Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-05-19 12:25:39 -04:00
Luis Chamberlain dd81faa883 fs: move locking sysctls where they are used
kernel/sysctl.c is a kitchen sink where everyone leaves their dirty
dishes, this makes it very difficult to maintain.

To help with this maintenance let's start by moving sysctls to places
where they actually belong.  The proc sysctl maintainers do not want to
know what sysctl knobs you wish to add for your own piece of code, we
just care about the core logic.

The locking fs sysctls are only used on fs/locks.c, so move them there.

Link: https://lkml.kernel.org/r/20211129205548.605569-7-mcgrof@kernel.org
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Lukas Middendorf <kernel@tuxforce.de>
Cc: Stephen Kitt <steve@sk2.org>
Cc: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-01-22 08:33:36 +02:00
J. Bruce Fields e9728cc72d locks: remove changelog comments
This is only of historical interest, and anyone interested in the
history can dig out an old version of locks.c from from git.

Triggered by the observation that it references the now-removed
Documentation/filesystems/mandatory-locking.rst.

Reported-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2021-10-19 14:11:39 -04:00
Jeff Layton 90f7d7a0d0 locks: remove LOCK_MAND flock lock support
As best I can tell, the logic for these has been broken for a long time
(at least before the move to git), such that they never conflict with
anything. Also, nothing checks for these flags and prevented opens or
read/write behavior on the files. They don't seem to do anything.

Given that, we can rip these symbols out of the kernel, and just make
flock(2) return 0 when LOCK_MAND is set in order to preserve existing
behavior.

Cc: Matthew Wilcox <willy@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2021-09-10 16:21:44 -04:00
Linus Torvalds 3754707bcc Revert "memcg: enable accounting for file lock caches"
This reverts commit 0f12156dff.

The kernel test robot reports a sizeable performance regression for this
commit, and while it clearly does the rigth thing in theory, we'll need
to look at just how to avoid or minimize the performance overhead of the
memcg accounting.

People already have suggestions on how to do that, but it's "future
work".

So revert it for now.

Link: https://lore.kernel.org/lkml/20210907150757.GE17617@xsang-OptiPlex-9020/
Acked-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-07 11:21:48 -07:00
Linus Torvalds 14726903c8 Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "173 patches.

  Subsystems affected by this series: ia64, ocfs2, block, and mm (debug,
  pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
  bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure,
  hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock,
  oom-kill, migration, ksm, percpu, vmstat, and madvise)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits)
  mm/madvise: add MADV_WILLNEED to process_madvise()
  mm/vmstat: remove unneeded return value
  mm/vmstat: simplify the array size calculation
  mm/vmstat: correct some wrong comments
  mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
  selftests: vm: add COW time test for KSM pages
  selftests: vm: add KSM merging time test
  mm: KSM: fix data type
  selftests: vm: add KSM merging across nodes test
  selftests: vm: add KSM zero page merging test
  selftests: vm: add KSM unmerge test
  selftests: vm: add KSM merge test
  mm/migrate: correct kernel-doc notation
  mm: wire up syscall process_mrelease
  mm: introduce process_mrelease system call
  memblock: make memblock_find_in_range method private
  mm/mempolicy.c: use in_task() in mempolicy_slab_node()
  mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
  mm/mempolicy: advertise new MPOL_PREFERRED_MANY
  mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
  ...
2021-09-03 10:08:28 -07:00
Vasily Averin 0f12156dff memcg: enable accounting for file lock caches
User can create file locks for each open file and force kernel to allocate
small but long-living objects per each open file.

It makes sense to account for these objects to limit the host's memory
consumption from inside the memcg-limited container.

Link: https://lkml.kernel.org/r/b009f4c7-f0ab-c0ec-8e83-918f47d677da@virtuozzo.com
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Yutian Yang <nglaive@gmail.com>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:12 -07:00
Jeff Layton f7e33bdbd6 fs: remove mandatory file locking support
We added CONFIG_MANDATORY_FILE_LOCKING in 2015, and soon after turned it
off in Fedora and RHEL8. Several other distros have followed suit.

I've heard of one problem in all that time: Someone migrated from an
older distro that supported "-o mand" to one that didn't, and the host
had a fstab entry with "mand" in it which broke on reboot. They didn't
actually _use_ mandatory locking so they just removed the mount option
and moved on.

This patch rips out mandatory locking support wholesale from the kernel,
along with the Kconfig option and the Documentation file. It also
changes the mount code to ignore the "mand" mount option instead of
erroring out, and to throw a big, ugly warning.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
2021-08-23 06:15:36 -04:00
Linus Torvalds a79cdfba68 Additional fixes and clean-ups for NFSD since tags/nfsd-5.13,
including a fix to grant read delegations for files open for
 writing.
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Merge tag 'nfsd-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull more nfsd updates from Chuck Lever:
 "Additional fixes and clean-ups for NFSD since tags/nfsd-5.13,
  including a fix to grant read delegations for files open for writing"

* tag 'nfsd-5.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  SUNRPC: Fix null pointer dereference in svc_rqst_free()
  SUNRPC: fix ternary sign expansion bug in tracing
  nfsd: Fix fall-through warnings for Clang
  nfsd: grant read delegations to clients holding writes
  nfsd: reshuffle some code
  nfsd: track filehandle aliasing in nfs4_files
  nfsd: hash nfs4_files by inode number
  nfsd: ensure new clients break delegations
  nfsd: removed unused argument in nfsd_startup_generic()
  nfsd: remove unused function
  svcrdma: Pass a useful error code to the send_err tracepoint
  svcrdma: Rename goto labels in svc_rdma_sendto()
  svcrdma: Don't leak send_ctxt on Send errors
2021-05-05 13:44:19 -07:00
Linus Torvalds befbfe07e6 File locking fixes for v5.13
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Merge tag 'locks-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux

Pull file locking updates from Jeff Layton:
 "When we reworked the blocked locks into a tree structure instead of a
  flat list a few releases ago, we lost the ability to see all of the
  file locks in /proc/locks. Luo's patch fixes it to dump out all of the
  blocked locks instead, which restores the full output.

  This changes the format of /proc/locks as the blocked locks are shown
  at multiple levels of indentation now, but lslocks (the only common
  program I've ID'ed that scrapes this info) seems to be OK with that.

  Tian also contributed a small patch to remove a useless assignment"

* tag 'locks-v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
  fs/locks: remove useless assignment in fcntl_getlk
  fs/locks: print full locks information
2021-04-26 13:24:39 -07:00
J. Bruce Fields aba2072f45 nfsd: grant read delegations to clients holding writes
It's OK to grant a read delegation to a client that holds a write,
as long as it's the only client holding the write.

We originally tried to do this in commit 94415b06eb ("nfsd4: a
client's own opens needn't prevent delegations"), which had to be
reverted in commit 6ee65a7730 ("Revert "nfsd4: a client's own
opens needn't prevent delegations"").

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-04-19 16:41:36 -04:00
Tian Tao cbe6fc4e01 fs/locks: remove useless assignment in fcntl_getlk
Function parameter 'cmd' is rewritten with unused value at locks.c

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2021-04-13 07:26:38 -04:00
Luo Longjun b8da9b10e2 fs/locks: print full locks information
Commit fd7732e033 ("fs/locks: create a tree of dependent requests.")
has put blocked locks into a tree.

So, with a for loop, we can't check all locks information.

To solve this problem, we should traverse the tree.

Signed-off-by: Luo Longjun <luolongjun@huawei.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2021-03-11 07:48:11 -05:00
J. Bruce Fields 6ee65a7730 Revert "nfsd4: a client's own opens needn't prevent delegations"
This reverts commit 94415b06eb.

That commit claimed to allow a client to get a read delegation when it
was the only writer.  Actually it allowed a client to get a read
delegation when *any* client has a write open!

The main problem is that it's depending on nfs4_clnt_odstate structures
that are actually only maintained for pnfs exports.

This causes clients to miss writes performed by other clients, even when
there have been intervening closes and opens, violating close-to-open
cache consistency.

We can do this a different way, but first we should just revert this.

I've added pynfs 4.1 test DELEG19 to test for this, as I should have
done originally!

Cc: stable@vger.kernel.org
Reported-by: Timo Rothenpieler <timo@rothenpieler.org>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2021-03-09 10:37:34 -05:00
Linus Torvalds faf145d6f3 Merge branch 'exec-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull execve updates from Eric Biederman:
 "This set of changes ultimately fixes the interaction of posix file
  lock and exec. Fundamentally most of the change is just moving where
  unshare_files is called during exec, and tweaking the users of
  files_struct so that the count of files_struct is not unnecessarily
  played with.

  Along the way fcheck and related helpers were renamed to more
  accurately reflect what they do.

  There were also many other small changes that fell out, as this is the
  first time in a long time much of this code has been touched.

  Benchmarks haven't turned up any practical issues but Al Viro has
  observed a possibility for a lot of pounding on task_lock. So I have
  some changes in progress to convert put_files_struct to always rcu
  free files_struct. That wasn't ready for the merge window so that will
  have to wait until next time"

* 'exec-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits)
  exec: Move io_uring_task_cancel after the point of no return
  coredump: Document coredump code exclusively used by cell spufs
  file: Remove get_files_struct
  file: Rename __close_fd_get_file close_fd_get_file
  file: Replace ksys_close with close_fd
  file: Rename __close_fd to close_fd and remove the files parameter
  file: Merge __alloc_fd into alloc_fd
  file: In f_dupfd read RLIMIT_NOFILE once.
  file: Merge __fd_install into fd_install
  proc/fd: In fdinfo seq_show don't use get_files_struct
  bpf/task_iter: In task_file_seq_get_next use task_lookup_next_fd_rcu
  proc/fd: In proc_readfd_common use task_lookup_next_fd_rcu
  file: Implement task_lookup_next_fd_rcu
  kcmp: In get_file_raw_ptr use task_lookup_fd_rcu
  proc/fd: In tid_fd_mode use task_lookup_fd_rcu
  file: Implement task_lookup_fd_rcu
  file: Rename fcheck lookup_fd_rcu
  file: Replace fcheck_files with files_lookup_fd_rcu
  file: Factor files_lookup_fd_locked out of fcheck_files
  file: Rename __fcheck_files to files_lookup_fd_raw
  ...
2020-12-15 19:29:43 -08:00
Eric W. Biederman 120ce2b0cd file: Factor files_lookup_fd_locked out of fcheck_files
To make it easy to tell where files->file_lock protection is being
used when looking up a file create files_lookup_fd_locked.  Only allow
this function to be called with the file_lock held.

Update the callers of fcheck and fcheck_files that are called with the
files->file_lock held to call files_lookup_fd_locked instead.

Hopefully this makes it easier to quickly understand what is going on.

The need for better names became apparent in the last round of
discussion of this set of changes[1].

[1] https://lkml.kernel.org/r/CAHk-=wj8BQbgJFLa+J0e=iT-1qpmCRTbPAJ8gd6MJQ=kbRPqyQ@mail.gmail.com
Link: https://lkml.kernel.org/r/20201120231441.29911-8-ebiederm@xmission.com
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-12-10 12:39:59 -06:00
Mauro Carvalho Chehab 529adfe8f1 locks: fix a typo at a kernel-doc markup
locks_delete_lock -> locks_delete_block

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2020-10-26 08:00:39 -04:00
Luo Meng 16238415eb locks: Fix UBSAN undefined behaviour in flock64_to_posix_lock
When the sum of fl->fl_start and l->l_len overflows,
UBSAN shows the following warning:

UBSAN: Undefined behaviour in fs/locks.c:482:29
signed integer overflow: 2 + 9223372036854775806
cannot be represented in type 'long long int'
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xe4/0x14e lib/dump_stack.c:118
 ubsan_epilogue+0xe/0x81 lib/ubsan.c:161
 handle_overflow+0x193/0x1e2 lib/ubsan.c:192
 flock64_to_posix_lock fs/locks.c:482 [inline]
 flock_to_posix_lock+0x595/0x690 fs/locks.c:515
 fcntl_setlk+0xf3/0xa90 fs/locks.c:2262
 do_fcntl+0x456/0xf60 fs/fcntl.c:387
 __do_sys_fcntl fs/fcntl.c:483 [inline]
 __se_sys_fcntl fs/fcntl.c:468 [inline]
 __x64_sys_fcntl+0x12d/0x180 fs/fcntl.c:468
 do_syscall_64+0xc8/0x5a0 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fix it by parenthesizing 'l->l_len - 1'.

Signed-off-by: Luo Meng <luomeng12@huawei.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2020-10-26 07:59:29 -04:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Linus Torvalds 7a6b60441f Highlights:
- Support for user extended attributes on NFS (RFC 8276)
 - Further reduce unnecessary NFSv4 delegation recalls
 
 Notable fixes:
 
 - Fix recent krb5p regression
 - Address a few resource leaks and a rare NULL dereference
 
 Other:
 
 - De-duplicate RPC/RDMA error handling and other utility functions
 - Replace storage and display of kernel memory addresses by tracepoints
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Merge tag 'nfsd-5.9' of git://git.linux-nfs.org/projects/cel/cel-2.6

Pull NFS server updates from Chuck Lever:
 "Highlights:
   - Support for user extended attributes on NFS (RFC 8276)
   - Further reduce unnecessary NFSv4 delegation recalls

  Notable fixes:
   - Fix recent krb5p regression
   - Address a few resource leaks and a rare NULL dereference

  Other:
   - De-duplicate RPC/RDMA error handling and other utility functions
   - Replace storage and display of kernel memory addresses by tracepoints"

* tag 'nfsd-5.9' of git://git.linux-nfs.org/projects/cel/cel-2.6: (38 commits)
  svcrdma: CM event handler clean up
  svcrdma: Remove transport reference counting
  svcrdma: Fix another Receive buffer leak
  SUNRPC: Refresh the show_rqstp_flags() macro
  nfsd: netns.h: delete a duplicated word
  SUNRPC: Fix ("SUNRPC: Add "@len" parameter to gss_unwrap()")
  nfsd: avoid a NULL dereference in __cld_pipe_upcall()
  nfsd4: a client's own opens needn't prevent delegations
  nfsd: Use seq_putc() in two functions
  svcrdma: Display chunk completion ID when posting a rw_ctxt
  svcrdma: Record send_ctxt completion ID in trace_svcrdma_post_send()
  svcrdma: Introduce Send completion IDs
  svcrdma: Record Receive completion ID in svc_rdma_decode_rqst
  svcrdma: Introduce Receive completion IDs
  svcrdma: Introduce infrastructure to support completion IDs
  svcrdma: Add common XDR encoders for RDMA and Read segments
  svcrdma: Add common XDR decoders for RDMA and Read segments
  SUNRPC: Add helpers for decoding list discriminators symbolically
  svcrdma: Remove declarations for functions long removed
  svcrdma: Clean up trace_svcrdma_send_failed() tracepoint
  ...
2020-08-09 13:58:04 -07:00
Linus Torvalds 3208167a86 File locking fix for v5.9.
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Merge tag 'filelock-v5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux

Pull file locking fix from Jeff Layton:
 "Just a single, one-line patch to fix an inefficiency in the posix
  locking code that can lead to it doing more wakeups than necessary"

* tag 'filelock-v5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux:
  locks: add locks_move_blocks in posix_lock_inode
2020-08-03 10:46:41 -07:00
J. Bruce Fields 94415b06eb nfsd4: a client's own opens needn't prevent delegations
We recently fixed lease breaking so that a client's actions won't break
its own delegations.

But we still have an unnecessary self-conflict when granting
delegations: a client's own write opens will prevent us from handing out
a read delegation even when no other client has the file open for write.

Fix that by turning off the checks for conflicting opens under
vfs_setlease, and instead performing those checks in the nfsd code.

We don't depend much on locks here: instead we acquire the delegation,
then check for conflicts, and drop the delegation again if we find any.

The check beforehand is an optimization of sorts, just to avoid
acquiring the delegation unnecessarily.  There's a race where the first
check could cause us to deny the delegation when we could have granted
it.  But, that's OK, delegation grants are optional (and probably not
even a good idea in that case).

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2020-07-13 17:28:46 -04:00
Linus Torvalds c742b63473 Highlights:
- Keep nfsd clients from unnecessarily breaking their own delegations:
   Note this requires a small kthreadd addition, discussed at:
   https://lore.kernel.org/r/1588348912-24781-1-git-send-email-bfields@redhat.com
   The result is Tejun Heo's suggestion, and he was OK with this going
   through my tree.
 - Patch nfsd/clients/ to display filenames, and to fix byte-order when
   displaying stateid's.
 - fix a module loading/unloading bug, from Neil Brown.
 - A big series from Chuck Lever with RPC/RDMA and tracing improvements,
   and lay some groundwork for RPC-over-TLS.
 
 Note Stephen Rothwell spotted two conflicts in linux-next.  Both should
 be straightforward:
 	include/trace/events/sunrpc.h
 		https://lore.kernel.org/r/20200529105917.50dfc40f@canb.auug.org.au
 	net/sunrpc/svcsock.c
 		https://lore.kernel.org/r/20200529131955.26c421db@canb.auug.org.au
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Merge tag 'nfsd-5.8' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "Highlights:

   - Keep nfsd clients from unnecessarily breaking their own
     delegations.

     Note this requires a small kthreadd addition. The result is Tejun
     Heo's suggestion (see link), and he was OK with this going through
     my tree.

   - Patch nfsd/clients/ to display filenames, and to fix byte-order
     when displaying stateid's.

   - fix a module loading/unloading bug, from Neil Brown.

   - A big series from Chuck Lever with RPC/RDMA and tracing
     improvements, and lay some groundwork for RPC-over-TLS"

Link: https://lore.kernel.org/r/1588348912-24781-1-git-send-email-bfields@redhat.com

* tag 'nfsd-5.8' of git://linux-nfs.org/~bfields/linux: (49 commits)
  sunrpc: use kmemdup_nul() in gssp_stringify()
  nfsd: safer handling of corrupted c_type
  nfsd4: make drc_slab global, not per-net
  SUNRPC: Remove unreachable error condition in rpcb_getport_async()
  nfsd: Fix svc_xprt refcnt leak when setup callback client failed
  sunrpc: clean up properly in gss_mech_unregister()
  sunrpc: svcauth_gss_register_pseudoflavor must reject duplicate registrations.
  sunrpc: check that domain table is empty at module unload.
  NFSD: Fix improperly-formatted Doxygen comments
  NFSD: Squash an annoying compiler warning
  SUNRPC: Clean up request deferral tracepoints
  NFSD: Add tracepoints for monitoring NFSD callbacks
  NFSD: Add tracepoints to the NFSD state management code
  NFSD: Add tracepoints to NFSD's duplicate reply cache
  SUNRPC: svc_show_status() macro should have enum definitions
  SUNRPC: Restructure svc_udp_recvfrom()
  SUNRPC: Refactor svc_recvfrom()
  SUNRPC: Clean up svc_release_skb() functions
  SUNRPC: Refactor recvfrom path dealing with incomplete TCP receives
  SUNRPC: Replace dprintk() call sites in TCP receive path
  ...
2020-06-11 10:33:13 -07:00
Linus Torvalds 9ff7258575 Merge branch 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull proc updates from Eric Biederman:
 "This has four sets of changes:

   - modernize proc to support multiple private instances

   - ensure we see the exit of each process tid exactly

   - remove has_group_leader_pid

   - use pids not tasks in posix-cpu-timers lookup

  Alexey updated proc so each mount of proc uses a new superblock. This
  allows people to actually use mount options with proc with no fear of
  messing up another mount of proc. Given the kernel's internal mounts
  of proc for things like uml this was a real problem, and resulted in
  Android's hidepid mount options being ignored and introducing security
  issues.

  The rest of the changes are small cleanups and fixes that came out of
  my work to allow this change to proc. In essence it is swapping the
  pids in de_thread during exec which removes a special case the code
  had to handle. Then updating the code to stop handling that special
  case"

* 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  proc: proc_pid_ns takes super_block as an argument
  remove the no longer needed pid_alive() check in __task_pid_nr_ns()
  posix-cpu-timers: Replace __get_task_for_clock with pid_for_clock
  posix-cpu-timers: Replace cpu_timer_pid_type with clock_pid_type
  posix-cpu-timers: Extend rcu_read_lock removing task_struct references
  signal: Remove has_group_leader_pid
  exec: Remove BUG_ON(has_group_leader_pid)
  posix-cpu-timer:  Unify the now redundant code in lookup_task
  posix-cpu-timer: Tidy up group_leader logic in lookup_task
  proc: Ensure we see the exit of each process tid exactly once
  rculist: Add hlists_swap_heads_rcu
  proc: Use PIDTYPE_TGID in next_tgid
  Use proc_pid_ns() to get pid_namespace from the proc superblock
  proc: use named enums for better readability
  proc: use human-readable values for hidepid
  docs: proc: add documentation for "hidepid=4" and "subset=pid" options and new mount behavior
  proc: add option to mount only a pids subset
  proc: instantiate only pids that we can ptrace on 'hidepid=4' mount option
  proc: allow to mount many instances of proc in one pid namespace
  proc: rename struct proc_fs_info to proc_fs_opts
2020-06-04 13:54:34 -07:00
yangerkun 5ef1596813 locks: add locks_move_blocks in posix_lock_inode
We forget to call locks_move_blocks in posix_lock_inode when try to
process same owner and different types.

Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2020-06-02 12:08:25 -04:00
Alexey Gladkov 9d78edeaec proc: proc_pid_ns takes super_block as an argument
syzbot found that

  touch /proc/testfile

causes NULL pointer dereference at tomoyo_get_local_path()
because inode of the dentry is NULL.

Before c59f415a7c, Tomoyo received pid_ns from proc's s_fs_info
directly. Since proc_pid_ns() can only work with inode, using it in
the tomoyo_get_local_path() was wrong.

To avoid creating more functions for getting proc_ns, change the
argument type of the proc_pid_ns() function. Then, Tomoyo can use
the existing super_block to get pid_ns.

Link: https://lkml.kernel.org/r/0000000000002f0c7505a5b0e04c@google.com
Link: https://lkml.kernel.org/r/20200518180738.2939611-1-gladkov.alexey@gmail.com
Reported-by: syzbot+c1af344512918c61362c@syzkaller.appspotmail.com
Fixes: c59f415a7c ("Use proc_pid_ns() to get pid_namespace from the proc superblock")
Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-05-19 07:07:50 -05:00
J. Bruce Fields 28df3d1539 nfsd: clients don't need to break their own delegations
We currently revoke read delegations on any write open or any operation
that modifies file data or metadata (including rename, link, and
unlink).  But if the delegation in question is the only read delegation
and is held by the client performing the operation, that's not really
necessary.

It's not always possible to prevent this in the NFSv4.0 case, because
there's not always a way to determine which client an NFSv4.0 delegation
came from.  (In theory we could try to guess this from the transport
layer, e.g., by assuming all traffic on a given TCP connection comes
from the same client.  But that's not really correct.)

In the NFSv4.1 case the session layer always tells us the client.

This patch should remove such self-conflicts in all cases where we can
reliably determine the client from the compound.

To do that we need to track "who" is performing a given (possibly
lease-breaking) file operation.  We're doing that by storing the
information in the svc_rqst and using kthread_data() to map the current
task back to a svc_rqst.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-05-08 21:23:10 -04:00
Mauro Carvalho Chehab a02dcdf65b docs: filesystems: convert mandatory-locking.txt to ReST
- Add a SPDX header;
- Adjust document title;
- Some whitespace fixes and new line breaks;
- Use notes markups;
- Add it to filesystems/index.rst.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/aecd6259fe9f99b2c2b3440eab6a2b989125e00d.1588021877.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-05-05 09:22:22 -06:00
Alexey Gladkov c59f415a7c Use proc_pid_ns() to get pid_namespace from the proc superblock
To get pid_namespace from the procfs superblock should be used a special
helper. This will avoid errors when s_fs_info will change the type.

Link: https://lore.kernel.org/lkml/20200423200316.164518-3-gladkov.alexey@gmail.com/
Link: https://lore.kernel.org/lkml/20200423112858.95820-1-gladkov.alexey@gmail.com/
Link: https://lore.kernel.org/lkml/06B50A1C-406F-4057-BFA8-3A7729EA7469@lca.pw/
Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2020-04-24 16:38:30 -05:00
Linus Torvalds dcf23ac3e8 locks: reinstate locks_delete_block optimization
There is measurable performance impact in some synthetic tests due to
commit 6d390e4b5d (locks: fix a potential use-after-free problem when
wakeup a waiter). Fix the race condition instead by clearing the
fl_blocker pointer after the wake_up, using explicit acquire/release
semantics.

This does mean that we can no longer use the clearing of fl_blocker as
the wait condition, so switch the waiters over to checking whether the
fl_blocked_member list_head is empty.

Reviewed-by: yangerkun <yangerkun@huawei.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Fixes: 6d390e4b5d (locks: fix a potential use-after-free problem when wakeup a waiter)
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-18 13:03:38 -07:00
yangerkun 6d390e4b5d locks: fix a potential use-after-free problem when wakeup a waiter
'16306a61d3b7 ("fs/locks: always delete_block after waiting.")' add the
logic to check waiter->fl_blocker without blocked_lock_lock. And it will
trigger a UAF when we try to wakeup some waiter:

Thread 1 has create a write flock a on file, and now thread 2 try to
unlock and delete flock a, thread 3 try to add flock b on the same file.

Thread2                         Thread3
                                flock syscall(create flock b)
	                        ...flock_lock_inode_wait
				    flock_lock_inode(will insert
				    our fl_blocked_member list
				    to flock a's fl_blocked_requests)
				   sleep
flock syscall(unlock)
...flock_lock_inode_wait
    locks_delete_lock_ctx
    ...__locks_wake_up_blocks
        __locks_delete_blocks(
	b->fl_blocker = NULL)
	...
                                   break by a signal
				   locks_delete_block
				    b->fl_blocker == NULL &&
				    list_empty(&b->fl_blocked_requests)
	                            success, return directly
				 locks_free_lock b
	wake_up(&b->fl_waiter)
	trigger UAF

Fix it by remove this logic, and this patch may also fix CVE-2019-19769.

Cc: stable@vger.kernel.org
Fixes: 16306a61d3 ("fs/locks: always delete_block after waiting.")
Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2020-03-06 11:54:13 -05:00
Amir Goldstein 98ca480a8f locks: print unsigned ino in /proc/locks
An ino is unsigned, so display it as such in /proc/locks.

Cc: stable@vger.kernel.org
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2019-12-29 09:00:58 -05:00
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
Wenwen Wang cfddf9f4c9 locks: fix a memory leak bug in __break_lease()
In __break_lease(), the file lock 'new_fl' is allocated in lease_alloc().
However, it is not deallocated in the following execution if
smp_load_acquire() fails, leading to a memory leak bug. To fix this issue,
free 'new_fl' before returning the error.

Signed-off-by: Wenwen Wang <wenwen@cs.uga.edu>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2019-08-20 05:48:52 -04:00
Jeff Layton eb82dd3937 nfsd: convert fi_deleg_file and ls_file fields to nfsd_file
Have them keep an nfsd_file reference instead of a struct file.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-08-19 11:09:09 -04:00
Jeff Layton 18f6622ebb locks: create a new notifier chain for lease attempts
With the new file caching infrastructure in nfsd, we can end up holding
files open for an indefinite period of time, even when they are still
idle. This may prevent the kernel from handing out leases on the file,
which is something we don't want to block.

Fix this by running a SRCU notifier call chain whenever on any
lease attempt. nfsd can then purge the cache for that inode before
returning.

Since SRCU is only conditionally compiled in, we must only define the
new chain if it's enabled, and users of the chain must ensure that
SRCU is enabled.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-08-19 11:00:39 -04:00
Pavel Begunkov 43e4cb942e locks: Fix procfs output for file leases
Since commit 778fc546f7 ("locks: fix tracking of inprogress
lease breaks"), leases break don't change @fl_type but modifies
@fl_flags. However, procfs's part haven't been updated.

Previously, for a breaking lease the target type was printed (see
target_leasetype()), as returns fcntl(F_GETLEASE). But now it's always
"READ", as F_UNLCK no longer means "breaking". Unlike the previous
one, this behaviour don't provide a complete description of the lease.

There are /proc/pid/fdinfo/ outputs for a lease (the same for READ and
WRITE) breaked by O_WRONLY.
-- before:
lock:   1: LEASE  BREAKING  READ  2558 08:03:815793 0 EOF
-- after:
lock:   1: LEASE  BREAKING  UNLCK  2558 08:03:815793 0 EOF

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2019-07-25 07:49:44 -04:00
Linus Torvalds d2b6b4c832 Highlights:
- Add a new /proc/fs/nfsd/clients/ directory which exposes some
   long-requested information about NFSv4 clients (like open files) and
   allows forced revocation of client state.
 
 - Replace the global duplicate reply cache by a cache per network
   namespace; previously, a request in one network namespace could
   incorrectly match an entry from another, though we haven't seen this
   in production.  This is the last remaining container bug that I'm
   aware of; at this point you should be able to run separate nfsd's in
   each network namespace, each with their own set of exports, and
   everything should work.
 
 - Cleanup and modify lock code to show the pid of lockd as the owner of
   NLM locks.  This is the correct version of the bugfix originally
   attempted in b8eee0e90f "lockd: Show pid of lockd for remote locks".
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Merge tag 'nfsd-5.3' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "Highlights:

   - Add a new /proc/fs/nfsd/clients/ directory which exposes some
     long-requested information about NFSv4 clients (like open files)
     and allows forced revocation of client state.

   - Replace the global duplicate reply cache by a cache per network
     namespace; previously, a request in one network namespace could
     incorrectly match an entry from another, though we haven't seen
     this in production. This is the last remaining container bug that
     I'm aware of; at this point you should be able to run separate
     nfsd's in each network namespace, each with their own set of
     exports, and everything should work.

   - Cleanup and modify lock code to show the pid of lockd as the owner
     of NLM locks. This is the correct version of the bugfix originally
     attempted in b8eee0e90f ("lockd: Show pid of lockd for remote
     locks")"

* tag 'nfsd-5.3' of git://linux-nfs.org/~bfields/linux: (34 commits)
  nfsd: Make __get_nfsdfs_client() static
  nfsd: Make two functions static
  nfsd: Fix misuse of strlcpy
  sunrpc/cache: remove the exporting of cache_seq_next
  nfsd: decode implementation id
  nfsd: create xdr_netobj_dup helper
  nfsd: allow forced expiration of NFSv4 clients
  nfsd: create get_nfsdfs_clp helper
  nfsd4: show layout stateids
  nfsd: show lock and deleg stateids
  nfsd4: add file to display list of client's opens
  nfsd: add more information to client info file
  nfsd: escape high characters in binary data
  nfsd: copy client's address including port number to cl_addr
  nfsd4: add a client info file
  nfsd: make client/ directory names small ints
  nfsd: add nfsd/clients directory
  nfsd4: use reference count to free client
  nfsd: rename cl_refcount
  nfsd: persist nfsd filesystem across mounts
  ...
2019-07-10 21:22:43 -07:00
Benjamin Coddington f85d93385e locks: Cleanup lm_compare_owner and lm_owner_key
After the update to use nlm_lockowners for the NLM server, there are no
more users of lm_compare_owner and lm_owner_key.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-07-03 17:52:09 -04:00
Amir Goldstein 387e3746d0 locks: eliminate false positive conflicts for write lease
check_conflicting_open() is checking for existing fd's open for read or
for write before allowing to take a write lease.  The check that was
implemented using i_count and d_count is an approximation that has
several false positives.  For example, overlayfs since v4.19, takes an
extra reference on the dentry; An open with O_PATH takes a reference on
the dentry although the file cannot be read nor written.

Change the implementation to use i_readcount and i_writecount to
eliminate the false positive conflicts and allow a write lease to be
taken on an overlayfs file.

The change of behavior with existing fd's open with O_PATH is symmetric
w.r.t. current behavior of lease breakers - an open with O_PATH currently
does not break a write lease.

This increases the size of struct inode by 4 bytes on 32bit archs when
CONFIG_FILE_LOCKING is defined and CONFIG_IMA was not already
defined.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2019-06-19 08:49:38 -04:00
Ira Weiny d51f527f44 locks: Add trace_leases_conflict
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
2019-06-19 08:49:37 -04:00
Thomas Gleixner 457c899653 treewide: Add SPDX license identifier for missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_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