linux-stable.git/fs/locks.c, branch v4.14.331

locks: print unsigned ino in /proc/locks

2020-01-09T09:17:55+00:00

commit 98ca480a8f22fdbd768e3dad07024c8d4856576c upstream.

An ino is unsigned, so display it as such in /proc/locks.

Cc: stable@vger.kernel.org
Signed-off-by: Amir Goldstein 
Signed-off-by: Jeff Layton 
Signed-off-by: Greg Kroah-Hartman

fs/lock: skip lock owner pid translation in case we are in init_pid_ns

2018-10-04T00:00:53+00:00

[ Upstream commit 826d7bc9f013d01e92997883d2fd0c25f4af1f1c ]

If the flock owner process is dead and its pid has been already freed,
pid translation won't work, but we still want to show flock owner pid
number when expecting /proc/$PID/fdinfo/$FD in init pidns.

Reproducer:
process A	process A1	process A2
fork()--------->
exit()		open()
		flock()
		fork()--------->
		exit()		sleep()

Before the patch:
================
(root@vz7)/: cat /proc/${PID_A2}/fdinfo/3
pos:    4
flags:  02100002
mnt_id: 257
lock:   (root@vz7)/:

After the patch:
===============
(root@vz7)/:cat /proc/${PID_A2}/fdinfo/3
pos:    4
flags:  02100002
mnt_id: 295
lock:   1: FLOCK  ADVISORY  WRITE ${PID_A1} b6:f8a61:529946 0 EOF

Fixes: 9d5b86ac13c5 ("fs/locks: Remove fl_nspid and use fs-specific l_pid for remote locks")
Signed-off-by: Konstantin Khorenko 
Acked-by: Andrey Vagin 
Reviewed-by: Benjamin Coddington 
Signed-off-by: Jeff Layton 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

locks: restore a warn for leaked locks on close

2017-07-21T17:57:31+00:00

When locks.c moved to using file_lock_context, the check for any locks that
were not released was moved from the __fput() to destroy_inode() path in
commit 8634b51f6ca2 ("locks: convert lease handling to file_lock_context").
This warning has been quite useful for catching bugs, particularly in NFS
where lock handling still sees some churn.

Let's bring back the warning for leaked locks on __fput, as this warning is
much more likely to be seen and reported by users.

Signed-off-by: Benjamin Coddington 
Signed-off-by: Jeff Layton

fs/locks: Remove fl_nspid and use fs-specific l_pid for remote locks

2017-07-16T14:28:22+00:00

Since commit c69899a17ca4 "NFSv4: Update of VFS byte range lock must be
atomic with the stateid update", NFSv4 has been inserting locks in rpciod
worker context.  The result is that the file_lock's fl_nspid is the
kworker's pid instead of the original userspace pid.

The fl_nspid is only used to represent the namespaced virtual pid number
when displaying locks or returning from F_GETLK.  There's no reason to set
it for every inserted lock, since we can usually just look it up from
fl_pid.  So, instead of looking up and holding struct pid for every lock,
let's just look up the virtual pid number from fl_pid when it is needed.
That means we can remove fl_nspid entirely.

The translaton and presentation of fl_pid should handle the following four
cases:

1 - F_GETLK on a remote file with a remote lock:
    In this case, the filesystem should determine the l_pid to return here.
    Filesystems should indicate that the fl_pid represents a non-local pid
    value that should not be translated by returning an fl_pid <= 0.

2 - F_GETLK on a local file with a remote lock:
    This should be the l_pid of the lock manager process, and translated.

3 - F_GETLK on a remote file with a local lock, and
4 - F_GETLK on a local file with a local lock:
    These should be the translated l_pid of the local locking process.

Fuse was already doing the correct thing by translating the pid into the
caller's namespace.  With this change we must update fuse to translate
to init's pid namespace, so that the locks API can then translate from
init's pid namespace into the pid namespace of the caller.

With this change, the locks API will expect that if a filesystem returns
a remote pid as opposed to a local pid for F_GETLK, that remote pid will
be <= 0.  This signifies that the pid is remote, and the locks API will
forego translating that pid into the pid namespace of the local calling
process.

Finally, we convert remote filesystems to present remote pids using
negative numbers. Have lustre, 9p, ceph, cifs, and dlm negate the remote
pid returned for F_GETLK lock requests.

Since local pids will never be larger than PID_MAX_LIMIT (which is
currently defined as <= 4 million), but pid_t is an unsigned int, we
should have plenty of room to represent remote pids with negative
numbers if we assume that remote pid numbers are similarly limited.

If this is not the case, then we run the risk of having a remote pid
returned for which there is also a corresponding local pid.  This is a
problem we have now, but this patch should reduce the chances of that
occurring, while also returning those remote pid numbers, for whatever
that may be worth.

Signed-off-by: Benjamin Coddington 
Signed-off-by: Jeff Layton

fs/locks: Use allocation rather than the stack in fcntl_getlk()

2017-07-16T14:28:21+00:00

Struct file_lock is fairly large, so let's save some space on the stack by
using an allocation for struct file_lock in fcntl_getlk(), just as we do
for fcntl_setlk().

Signed-off-by: Benjamin Coddington 
Signed-off-by: Jeff Layton

fs/locks: pass kernel struct flock to fcntl_getlk/setlk

2017-05-27T10:07:19+00:00

This will make it easier to implement a sane compat fcntl syscall.

[ jlayton: fix undeclared identifiers in 32-bit fcntl64 syscall handler ]

Signed-off-by: Christoph Hellwig 
Reviewed-by: Jeff Layton 
Signed-off-by: Jeff Layton

fs: locks: Fix some troubles at kernel-doc comments

2017-05-27T10:07:18+00:00

There are a few syntax violations that cause outputs of
a few comments to not be properly parsed in ReST format.

No functional changes.

Signed-off-by: Mauro Carvalho Chehab 
Signed-off-by: Jeff Layton

locks: Set FL_CLOSE when removing flock locks on close()

2017-04-21T14:45:01+00:00

Set FL_CLOSE in fl_flags as in locks_remove_posix() when clearing locks.
NFS will check for this flag to ensure an unlock is sent in a following
patch.

Fuse handles flock and posix locks differently for FL_CLOSE, and so
requires a fixup to retain the existing behavior for flock.

Signed-off-by: Benjamin Coddington 
Reviewed-by: Jeff Layton 
Acked-by: Miklos Szeredi 
Signed-off-by: Trond Myklebust

Replace with globally

2016-12-24T19:46:01+00:00

This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*'
  sed -i -e "s!$PATT!#include !" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro 
Signed-off-by: Linus Torvalds

locking, fs/locks: Add missing file_sem locks

2016-10-18T10:21:28+00:00

I overlooked a few code-paths that can lead to
locks_delete_global_locks().

Reported-by: Dmitry Vyukov 
Signed-off-by: Peter Zijlstra (Intel) 
Reviewed-by: Jeff Layton 
Cc: Al Viro 
Cc: Bruce Fields 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-fsdevel@vger.kernel.org
Cc: syzkaller 
Link: http://lkml.kernel.org/r/20161008081228.GF3142@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar