Commit graph

295 commits

Author SHA1 Message Date
David Howells
63afdfc781 VFS: Handle lower layer dentry/inode in pathwalk
Make use of d_backing_inode() in pathwalk to gain access to an
inode or dentry that's on a lower layer.

Signed-off-by: David Howells <dhowells@redhat.com>
2015-05-11 08:13:10 -04:00
Linus Torvalds
1aef882f02 xfs: update for 4.1-rc1
This update contains:
 o RENAME_WHITEOUT support
 o conversion of per-cpu superblock accounting to use generic counters
 o new inode mmap lock so that we can lock page faults out of truncate, hole
   punch and other direct extent manipulation functions to avoid racing mmap
   writes from causing data corruption
 o rework of direct IO submission and completion to solve data corruption issue
   when running concurrent extending DIO writes. Also solves problem of running
   IO completion transactions in interrupt context during size extending AIO
   writes.
 o FALLOC_FL_INSERT_RANGE support for inserting holes into a file via direct
   extent manipulation to avoid needing to copy data within the file
 o attribute block header field overflow fix for 64k block size filesystems
 o Lots of changes to log messaging to be more informative and concise when
   errors occur. Also prevent a lot of unnecessary log spamming due to cascading
   failures in error conditions.
 o lots of cleanups and bug fixes
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Merge tag 'xfs-for-linus-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs

Pull xfs update from Dave Chinner:
 "This update contains:

   - RENAME_WHITEOUT support

   - conversion of per-cpu superblock accounting to use generic counters

   - new inode mmap lock so that we can lock page faults out of
     truncate, hole punch and other direct extent manipulation functions
     to avoid racing mmap writes from causing data corruption

   - rework of direct IO submission and completion to solve data
     corruption issue when running concurrent extending DIO writes.
     Also solves problem of running IO completion transactions in
     interrupt context during size extending AIO writes.

   - FALLOC_FL_INSERT_RANGE support for inserting holes into a file via
     direct extent manipulation to avoid needing to copy data within the
     file

   - attribute block header field overflow fix for 64k block size
     filesystems

   - Lots of changes to log messaging to be more informative and concise
     when errors occur.  Also prevent a lot of unnecessary log spamming
     due to cascading failures in error conditions.

   - lots of cleanups and bug fixes

  One thing of note is the direct IO fixes that we merged last week
  after the window opened.  Even though a little late, they fix a user
  reported data corruption and have been pretty well tested.  I figured
  there was not much point waiting another 2 weeks for -rc1 to be
  released just so I could send them to you..."

* tag 'xfs-for-linus-4.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (49 commits)
  xfs: using generic_file_direct_write() is unnecessary
  xfs: direct IO EOF zeroing needs to drain AIO
  xfs: DIO write completion size updates race
  xfs: DIO writes within EOF don't need an ioend
  xfs: handle DIO overwrite EOF update completion correctly
  xfs: DIO needs an ioend for writes
  xfs: move DIO mapping size calculation
  xfs: factor DIO write mapping from get_blocks
  xfs: unlock i_mutex in xfs_break_layouts
  xfs: kill unnecessary firstused overflow check on attr3 leaf removal
  xfs: use larger in-core attr firstused field and detect overflow
  xfs: pass attr geometry to attr leaf header conversion functions
  xfs: disallow ro->rw remount on norecovery mount
  xfs: xfs_shift_file_space can be static
  xfs: Add support FALLOC_FL_INSERT_RANGE for fallocate
  fs: Add support FALLOC_FL_INSERT_RANGE for fallocate
  xfs: Fix incorrect positive ENOMEM return
  xfs: xfs_mru_cache_insert() should use GFP_NOFS
  xfs: %pF is only for function pointers
  xfs: fix shadow warning in xfs_da3_root_split()
  ...
2015-04-24 07:08:41 -07:00
Al Viro
8436318205 ->aio_read and ->aio_write removed
no remaining users

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:29:43 -04:00
Andrew Elble
c1b8940b42 NFS: fix BUG() crash in notify_change() with patch to chown_common()
We have observed a BUG() crash in fs/attr.c:notify_change(). The crash
occurs during an rsync into a filesystem that is exported via NFS.

1.) fs/attr.c:notify_change() modifies the caller's version of attr.
2.) 6de0ec00ba ("VFS: make notify_change pass ATTR_KILL_S*ID to
    setattr operations") introduced a BUG() restriction such that "no
    function will ever call notify_change() with both ATTR_MODE and
    ATTR_KILL_S*ID set". Under some circumstances though, it will have
    assisted in setting the caller's version of attr to this very
    combination.
3.) 27ac0ffeac ("locks: break delegations on any attribute
    modification") introduced code to handle breaking
    delegations. This can result in notify_change() being re-called. attr
    _must_ be explicitly reset to avoid triggering the BUG() established
    in #2.
4.) The path that that triggers this is via fs/open.c:chmod_common().
    The combination of attr flags set here and in the first call to
    notify_change() along with a later failed break_deleg_wait()
    results in notify_change() being called again via retry_deleg
    without resetting attr.

Solution is to move retry_deleg in chmod_common() a bit further up to
ensure attr is completely reset.

There are other places where this seemingly could occur, such as
fs/utimes.c:utimes_common(), but the attr flags are not initially
set in such a way to trigger this.

Fixes: 27ac0ffeac ("locks: break delegations on any attribute modification")
Reported-by: Eric Meddaugh <etmsys@rit.edu>
Tested-by: Eric Meddaugh <etmsys@rit.edu>
Signed-off-by: Andrew Elble <aweits@rit.edu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:24:34 -04:00
Al Viro
e5b811e38a drop bogus check in file_open_root()
For one thing, LOOKUP_DIRECTORY will be dealt with in do_last().
For another, name can be an empty string, but not NULL - no callers
pass that and it would oops immediately if they would.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11 22:24:32 -04:00
Namjae Jeon
dd46c78778 fs: Add support FALLOC_FL_INSERT_RANGE for fallocate
FALLOC_FL_INSERT_RANGE command is the opposite command of
FALLOC_FL_COLLAPSE_RANGE that is needed for someone who wants to add
some data in the middle of file.

FALLOC_FL_INSERT_RANGE will create space for writing new data within
a file after shifting extents to right as given length. This command
also has same limitations as FALLOC_FL_COLLAPSE_RANGE in that
operations need to be filesystem block boundary aligned and cannot
cross the current EOF.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-03-25 15:07:05 +11:00
Linus Torvalds
05016b0f0a Merge branch 'getname2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull getname/putname updates from Al Viro:
 "Rework of getname/getname_kernel/etc., mostly from Paul Moore.  Gets
  rid of quite a pile of kludges between namei and audit..."

* 'getname2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  audit: replace getname()/putname() hacks with reference counters
  audit: fix filename matching in __audit_inode() and __audit_inode_child()
  audit: enable filename recording via getname_kernel()
  simpler calling conventions for filename_mountpoint()
  fs: create proper filename objects using getname_kernel()
  fs: rework getname_kernel to handle up to PATH_MAX sized filenames
  cut down the number of do_path_lookup() callers
2015-02-17 15:27:47 -08:00
Matthew Wilcox
e748dcd095 vfs: remove get_xip_mem
All callers of get_xip_mem() are now gone.  Remove checks for it,
initialisers of it, documentation of it and the only implementation of it.
 Also remove mm/filemap_xip.c as it is now empty.  Also remove
documentation of the long-gone get_xip_page().

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Cc: Andreas Dilger <andreas.dilger@intel.com>
Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-16 17:56:03 -08:00
Paul Moore
5168910413 fs: create proper filename objects using getname_kernel()
There are several areas in the kernel that create temporary filename
objects using the following pattern:

	int func(const char *name)
	{
		struct filename *file = { .name = name };
		...
		return 0;
	}

... which for the most part works okay, but it causes havoc within the
audit subsystem as the filename object does not persist beyond the
lifetime of the function.  This patch converts all of these temporary
filename objects into proper filename objects using getname_kernel()
and putname() which ensure that the filename object persists until the
audit subsystem is finished with it.

Also, a special thanks to Al Viro, Guenter Roeck, and Sabrina Dubroca
for helping resolve a difficult kernel panic on boot related to a
use-after-free problem in kern_path_create(); the thread can be seen
at the link below:

 * https://lkml.org/lkml/2015/1/20/710

This patch includes code that was either based on, or directly written
by Al in the above thread.

CC: viro@zeniv.linux.org.uk
CC: linux@roeck-us.net
CC: sd@queasysnail.net
CC: linux-fsdevel@vger.kernel.org
Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-01-23 00:22:20 -05:00
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
Heinrich Schuchardt
820c12d5d6 fallocate: create FAN_MODIFY and IN_MODIFY events
The fanotify and the inotify API can be used to monitor changes of the
file system.  System call fallocate() modifies files.  Hence it should
trigger the corresponding fanotify (FAN_MODIFY) and inotify (IN_MODIFY)
events.  The most interesting case is FALLOC_FL_COLLAPSE_RANGE because
this value allows to create arbitrary file content from random data.

This patch adds the missing call to fsnotify_modify().

The FAN_MODIFY and IN_MODIFY event will be created when fallocate()
succeeds.  It will even be created if the file length remains unchanged,
e.g.  when calling fanotify with flag FALLOC_FL_KEEP_SIZE.

This logic was primarily chosen to keep the coding simple.

It resembles the logic of the write() system call.

When we call write() we always create a FAN_MODIFY event, even in the case
of overwriting with identical data.

Events FAN_MODIFY and IN_MODIFY do not provide any guarantee that data was
actually changed.

Furthermore even if if the filesize remains unchanged, fallocate() may
influence whether a subsequent write() will succeed and hence the
fallocate() call may be considered a modification.

The fallocate(2) man page teaches: After a successful call, subsequent
writes into the range specified by offset and len are guaranteed not to
fail because of lack of disk space.

So calling fallocate(fd, FALLOC_FL_KEEP_SIZE, offset, len) may result in
different outcomes of a subsequent write depending on the values of offset
and len.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jan Kara <jack@suse.cz>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@parisplace.org>
Cc: John McCutchan <john@johnmccutchan.com>
Cc: Robert Love <rlove@rlove.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-12-13 12:42:53 -08:00
Al Viro
9f45f5bf30 new helper: audit_file()
... for situations when we don't have any candidate in pathnames - basically,
in descriptor-based syscalls.

[Folded the build fix for !CONFIG_AUDITSYSCALL configs from Chen Gang]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-19 13:01:26 -05:00
J. Bruce Fields
56429e9b3b merge nfs bugfixes into nfsd for-3.19 branch
In addition to nfsd bugfixes, there are some fixes in -rc5 for client
bugs that can interfere with my testing.
2014-11-19 12:06:30 -05:00
Anna Schumaker
72c72bdf7b VFS: Rename do_fallocate() to vfs_fallocate()
This function needs to be exported so it can be used by the NFSD module
when responding to the new ALLOCATE and DEALLOCATE operations in NFS
v4.2.  Christoph Hellwig suggested renaming the function to stay
consistent with how other vfs functions are named.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-11-07 16:17:44 -05:00
Miklos Szeredi
4aa7c6346b vfs: add i_op->dentry_open()
Add a new inode operation i_op->dentry_open().  This is for stacked filesystems
that want to return a struct file from a different filesystem.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-10-24 00:14:35 +02:00
Eric Biggers
6d2b6170c8 vfs: fix check for fallocate on active swapfile
Fix the broken check for calling sys_fallocate() on an active swapfile,
introduced by commit 0790b31b69 ("fs: disallow all fallocate
operation on active swapfile").

Signed-off-by: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-08-01 02:36:04 -04:00
Al Viro
293bc9822f new methods: ->read_iter() and ->write_iter()
Beginning to introduce those.  Just the callers for now, and it's
clumsier than it'll eventually become; once we finish converting
aio_read and aio_write instances, the things will get nicer.

For now, these guys are in parallel to ->aio_read() and ->aio_write();
they take iocb and iov_iter, with everything in iov_iter already
validated.  File offset is passed in iocb->ki_pos, iov/nr_segs -
in iov_iter.

Main concerns in that series are stack footprint and ability to
split the damn thing cleanly.

[fix from Peter Ujfalusi <peter.ujfalusi@ti.com> folded]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:36:00 -04:00
Al Viro
7f7f25e82d replace checking for ->read/->aio_read presence with check in ->f_mode
Since we are about to introduce new methods (read_iter/write_iter), the
tests in a bunch of places would have to grow inconveniently.  Check
once (at open() time) and store results in ->f_mode as FMODE_CAN_READ
and FMODE_CAN_WRITE resp.  It might end up being a temporary measure -
once everything switches from ->aio_{read,write} to ->{read,write}_iter
it might make sense to return to open-coded checks.  We'll see...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06 17:32:55 -04:00
Linus Torvalds
9ac0367501 These are regression and bug fixes for ext4.
We had a number of new features in ext4 during this merge window
 (ZERO_RANGE and COLLAPSE_RANGE fallocate modes, renameat, etc.) so
 there were many more regression and bug fixes this time around.  It
 didn't help that xfstests hadn't been fully updated to fully stress
 test COLLAPSE_RANGE until after -rc1.
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 fixes from Ted Ts'o:
 "These are regression and bug fixes for ext4.

  We had a number of new features in ext4 during this merge window
  (ZERO_RANGE and COLLAPSE_RANGE fallocate modes, renameat, etc.) so
  there were many more regression and bug fixes this time around.  It
  didn't help that xfstests hadn't been fully updated to fully stress
  test COLLAPSE_RANGE until after -rc1"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (31 commits)
  ext4: disable COLLAPSE_RANGE for bigalloc
  ext4: fix COLLAPSE_RANGE failure with 1KB block size
  ext4: use EINVAL if not a regular file in ext4_collapse_range()
  ext4: enforce we are operating on a regular file in ext4_zero_range()
  ext4: fix extent merging in ext4_ext_shift_path_extents()
  ext4: discard preallocations after removing space
  ext4: no need to truncate pagecache twice in collapse range
  ext4: fix removing status extents in ext4_collapse_range()
  ext4: use filemap_write_and_wait_range() correctly in collapse range
  ext4: use truncate_pagecache() in collapse range
  ext4: remove temporary shim used to merge COLLAPSE_RANGE and ZERO_RANGE
  ext4: fix ext4_count_free_clusters() with EXT4FS_DEBUG and bigalloc enabled
  ext4: always check ext4_ext_find_extent result
  ext4: fix error handling in ext4_ext_shift_extents
  ext4: silence sparse check warning for function ext4_trim_extent
  ext4: COLLAPSE_RANGE only works on extent-based files
  ext4: fix byte order problems introduced by the COLLAPSE_RANGE patches
  ext4: use i_size_read in ext4_unaligned_aio()
  fs: disallow all fallocate operation on active swapfile
  fs: move falloc collapse range check into the filesystem methods
  ...
2014-04-20 20:43:47 -07:00
Linus Torvalds
5166701b36 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "The first vfs pile, with deep apologies for being very late in this
  window.

  Assorted cleanups and fixes, plus a large preparatory part of iov_iter
  work.  There's a lot more of that, but it'll probably go into the next
  merge window - it *does* shape up nicely, removes a lot of
  boilerplate, gets rid of locking inconsistencie between aio_write and
  splice_write and I hope to get Kent's direct-io rewrite merged into
  the same queue, but some of the stuff after this point is having
  (mostly trivial) conflicts with the things already merged into
  mainline and with some I want more testing.

  This one passes LTP and xfstests without regressions, in addition to
  usual beating.  BTW, readahead02 in ltp syscalls testsuite has started
  giving failures since "mm/readahead.c: fix readahead failure for
  memoryless NUMA nodes and limit readahead pages" - might be a false
  positive, might be a real regression..."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  missing bits of "splice: fix racy pipe->buffers uses"
  cifs: fix the race in cifs_writev()
  ceph_sync_{,direct_}write: fix an oops on ceph_osdc_new_request() failure
  kill generic_file_buffered_write()
  ocfs2_file_aio_write(): switch to generic_perform_write()
  ceph_aio_write(): switch to generic_perform_write()
  xfs_file_buffered_aio_write(): switch to generic_perform_write()
  export generic_perform_write(), start getting rid of generic_file_buffer_write()
  generic_file_direct_write(): get rid of ppos argument
  btrfs_file_aio_write(): get rid of ppos
  kill the 5th argument of generic_file_buffered_write()
  kill the 4th argument of __generic_file_aio_write()
  lustre: don't open-code kernel_recvmsg()
  ocfs2: don't open-code kernel_recvmsg()
  drbd: don't open-code kernel_recvmsg()
  constify blk_rq_map_user_iov() and friends
  lustre: switch to kernel_sendmsg()
  ocfs2: don't open-code kernel_sendmsg()
  take iov_iter stuff to mm/iov_iter.c
  process_vm_access: tidy up a bit
  ...
2014-04-12 14:49:50 -07:00
Lukas Czerner
0790b31b69 fs: disallow all fallocate operation on active swapfile
Currently some file system have IS_SWAPFILE check in their fallocate
implementations and some do not. However we should really prevent any
fallocate operation on swapfile so move the check to vfs and remove the
redundant checks from the file systems fallocate implementations.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-04-12 10:05:37 -04:00
Lukas Czerner
23fffa925e fs: move falloc collapse range check into the filesystem methods
Currently in do_fallocate in collapse range case we're checking
whether offset + len is not bigger than i_size.  However there is
nothing which would prevent i_size from changing so the check is
pointless.  It should be done in the file system itself and the file
system needs to make sure that i_size is not going to change.  The
i_size check for the other fallocate modes are also done in the
filesystems.

As it is now we can easily crash the kernel by having two processes
doing truncate and fallocate collapse range at the same time.  This
can be reproduced on ext4 and it is theoretically possible on xfs even
though I was not able to trigger it with this simple test.

This commit removes the check from do_fallocate and adds it to the
file system.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2014-04-12 09:56:41 -04:00
Lukas Czerner
8fc61d9263 fs: prevent doing FALLOC_FL_ZERO_RANGE on append only file
Currently punch hole and collapse range fallocate operation are not
allowed on append only file. This should be case for zero range as well.
Fix it by allowing only pure fallocate (possibly with keep size set).

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2014-04-12 09:51:34 -04:00
Linus Torvalds
d15e03104e xfs: update for 3.15-rc1
The main changes in the XFS tree for 3.15-rc1 are:
 
         - O_TMPFILE support
         - allowing AIO+DIO writes beyond EOF
         - FALLOC_FL_COLLAPSE_RANGE support for fallocate syscall and XFS
           implementation
         - FALLOC_FL_ZERO_RANGE support for fallocate syscall and XFS
           implementation
         - IO verifier cleanup and rework
         - stack usage reduction changes
         - vm_map_ram NOIO context fixes to remove lockdep warings
         - various bug fixes and cleanups
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Merge tag 'xfs-for-linus-3.15-rc1' of git://oss.sgi.com/xfs/xfs

Pull xfs update from Dave Chinner:
 "There are a couple of new fallocate features in this request - it was
  decided that it was easiest to push them through the XFS tree using
  topic branches and have the ext4 support be based on those branches.
  Hence you may see some overlap with the ext4 tree merge depending on
  how they including those topic branches into their tree.  Other than
  that, there is O_TMPFILE support, some cleanups and bug fixes.

  The main changes in the XFS tree for 3.15-rc1 are:

   - O_TMPFILE support
   - allowing AIO+DIO writes beyond EOF
   - FALLOC_FL_COLLAPSE_RANGE support for fallocate syscall and XFS
     implementation
   - FALLOC_FL_ZERO_RANGE support for fallocate syscall and XFS
     implementation
   - IO verifier cleanup and rework
   - stack usage reduction changes
   - vm_map_ram NOIO context fixes to remove lockdep warings
   - various bug fixes and cleanups"

* tag 'xfs-for-linus-3.15-rc1' of git://oss.sgi.com/xfs/xfs: (34 commits)
  xfs: fix directory hash ordering bug
  xfs: extra semi-colon breaks a condition
  xfs: Add support for FALLOC_FL_ZERO_RANGE
  fs: Introduce FALLOC_FL_ZERO_RANGE flag for fallocate
  xfs: inode log reservations are still too small
  xfs: xfs_check_page_type buffer checks need help
  xfs: avoid AGI/AGF deadlock scenario for inode chunk allocation
  xfs: use NOIO contexts for vm_map_ram
  xfs: don't leak EFSBADCRC to userspace
  xfs: fix directory inode iolock lockdep false positive
  xfs: allocate xfs_da_args to reduce stack footprint
  xfs: always do log forces via the workqueue
  xfs: modify verifiers to differentiate CRC from other errors
  xfs: print useful caller information in xfs_error_report
  xfs: add xfs_verifier_error()
  xfs: add helper for updating checksums on xfs_bufs
  xfs: add helper for verifying checksums on xfs_bufs
  xfs: Use defines for CRC offsets in all cases
  xfs: skip pointless CRC updates after verifier failures
  xfs: Add support FALLOC_FL_COLLAPSE_RANGE for fallocate
  ...
2014-04-04 15:50:08 -07:00
Al Viro
3f4d5a0007 tidy do_dentry_open() up a bit
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:13 -04:00
Al Viro
83f936c75e mark struct file that had write access grabbed by open()
new flag in ->f_mode - FMODE_WRITER.  Set by do_dentry_open() in case
when it has grabbed write access, checked by __fput() to decide whether
it wants to drop the sucker.  Allows to stop bothering with mnt_clone_write()
in alloc_file(), along with fewer special_file() checks.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:12 -04:00
Al Viro
0ccb286346 fold __get_file_write_access() into its only caller
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:12 -04:00
Al Viro
4597e695b8 get rid of DEBUG_WRITECOUNT
it only makes control flow in __fput() and friends more convoluted.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:12 -04:00
Al Viro
dd20908a8a don't bother with {get,put}_write_access() on non-regular files
it's pointless and actually leads to wrong behaviour in at least one
moderately convoluted case (pipe(), close one end, try to get to
another via /proc/*/fd and run into ETXTBUSY).

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:11 -04:00
Lukas Czerner
409332b65d fs: Introduce FALLOC_FL_ZERO_RANGE flag for fallocate
Introduce new FALLOC_FL_ZERO_RANGE flag for fallocate. This has the same
functionality as xfs ioctl XFS_IOC_ZERO_RANGE.

It can be used to convert a range of file to zeros preferably without
issuing data IO. Blocks should be preallocated for the regions that span
holes in the file, and the entire range is preferable converted to
unwritten extents - even though file system may choose to zero out the
extent or do whatever which will result in reading zeros from the range
while the range remains allocated for the file.

This can be also used to preallocate blocks past EOF in the same way as
with fallocate. Flag FALLOC_FL_KEEP_SIZE which should cause the inode
size to remain the same.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-03-13 19:07:42 +11:00
Linus Torvalds
9c225f2655 vfs: atomic f_pos accesses as per POSIX
Our write() system call has always been atomic in the sense that you get
the expected thread-safe contiguous write, but we haven't actually
guaranteed that concurrent writes are serialized wrt f_pos accesses, so
threads (or processes) that share a file descriptor and use "write()"
concurrently would quite likely overwrite each others data.

This violates POSIX.1-2008/SUSv4 Section XSI 2.9.7 that says:

 "2.9.7 Thread Interactions with Regular File Operations

  All of the following functions shall be atomic with respect to each
  other in the effects specified in POSIX.1-2008 when they operate on
  regular files or symbolic links: [...]"

and one of the effects is the file position update.

This unprotected file position behavior is not new behavior, and nobody
has ever cared.  Until now.  Yongzhi Pan reported unexpected behavior to
Michael Kerrisk that was due to this.

This resolves the issue with a f_pos-specific lock that is taken by
read/write/lseek on file descriptors that may be shared across threads
or processes.

Reported-by: Yongzhi Pan <panyongzhi@gmail.com>
Reported-by: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-03-10 11:44:41 -04:00
Namjae Jeon
00f5e61998 fs: Add new flag(FALLOC_FL_COLLAPSE_RANGE) for fallocate
This patch is in response of the following post:
http://lwn.net/Articles/556136/
"ext4: introduce two new ioctls"

Dave chinner suggested that truncate_block_range
(which was one of the ioctls name) should be a fallocate operation
and not any fs specific ioctl, hence we add this functionality to new flags of fallocate.

This new functionality of collapsing range could be used by media editing tools
which does non linear editing to quickly purge and edit parts of a media file.
This will immensely improve the performance of these operations.
The limitation of fs block size aligned offsets can be easily handled
by media codecs which are encapsulated in a conatiner as they have to
just change the offset to next keyframe value to match the proper alignment.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-02-24 10:58:15 +11:00
J. Bruce Fields
27ac0ffeac locks: break delegations on any attribute modification
NFSv4 uses leases to guarantee that clients can cache metadata as well
as data.

Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Cc: David Howells <dhowells@redhat.com>
Cc: Tyler Hicks <tyhicks@canonical.com>
Cc: Dustin Kirkland <dustin.kirkland@gazzang.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:44 -05:00
Al Viro
eee5cc2702 get rid of s_files and files_lock
The only thing we need it for is alt-sysrq-r (emergency remount r/o)
and these days we can do just as well without going through the
list of files.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-11-09 00:16:20 -05:00
Al Viro
72c2d53192 file->f_op is never NULL...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:34:54 -04:00
Miklos Szeredi
0854d450e2 vfs: improve i_op->atomic_open() documentation
Fix documentation of ->atomic_open() and related functions: finish_open()
and finish_no_open().  Also add details that seem to be unclear and a
source of bugs (some of which are fixed in the following series).

Cc-ing maintainers of all filesystems implementing ->atomic_open().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Cc: Sage Weil <sage@inktank.com>
Cc: Steve French <sfrench@samba.org>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-16 19:17:24 -04:00
Linus Torvalds
c7c4591db6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull namespace changes from Eric Biederman:
 "This is an assorted mishmash of small cleanups, enhancements and bug
  fixes.

  The major theme is user namespace mount restrictions.  nsown_capable
  is killed as it encourages not thinking about details that need to be
  considered.  A very hard to hit pid namespace exiting bug was finally
  tracked and fixed.  A couple of cleanups to the basic namespace
  infrastructure.

  Finally there is an enhancement that makes per user namespace
  capabilities usable as capabilities, and an enhancement that allows
  the per userns root to nice other processes in the user namespace"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  userns:  Kill nsown_capable it makes the wrong thing easy
  capabilities: allow nice if we are privileged
  pidns: Don't have unshare(CLONE_NEWPID) imply CLONE_THREAD
  userns: Allow PR_CAPBSET_DROP in a user namespace.
  namespaces: Simplify copy_namespaces so it is clear what is going on.
  pidns: Fix hang in zap_pid_ns_processes by sending a potentially extra wakeup
  sysfs: Restrict mounting sysfs
  userns: Better restrictions on when proc and sysfs can be mounted
  vfs: Don't copy mount bind mounts of /proc/<pid>/ns/mnt between namespaces
  kernel/nsproxy.c: Improving a snippet of code.
  proc: Restrict mounting the proc filesystem
  vfs: Lock in place mounts from more privileged users
2013-09-07 14:35:32 -07:00
Al Viro
173c84012a switch fchmod() to fdget
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-03 23:04:45 -04:00
Eric W. Biederman
c7b96acf14 userns: Kill nsown_capable it makes the wrong thing easy
nsown_capable is a special case of ns_capable essentially for just CAP_SETUID and
CAP_SETGID.  For the existing users it doesn't noticably simplify things and
from the suggested patches I have seen it encourages people to do the wrong
thing.  So remove nsown_capable.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-08-30 23:44:11 -07:00
Andy Lutomirski
e305f48bc4 fs: Fix file mode for O_TMPFILE
O_TMPFILE, like O_CREAT, should respect the requested mode and should
create regular files.

This fixes two bugs: O_TMPFILE required privilege (because the mode
ended up as 000) and it produced bogus inodes with no type.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-08-05 18:24:10 +04:00
Al Viro
ba57ea64cb allow O_TMPFILE to work with O_WRONLY
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-20 03:11:32 +04:00
Al Viro
bb458c644a Safer ABI for O_TMPFILE
[suggested by Rasmus Villemoes] make O_DIRECTORY | O_RDWR part of O_TMPFILE;
that will fail on old kernels in a lot more cases than what I came up with.
And make sure O_CREAT doesn't get there...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-07-13 13:26:37 +04:00
Al Viro
60545d0d46 [O_TMPFILE] it's still short a few helpers, but infrastructure should be OK now...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:57:10 +04:00
Al Viro
f9652e10c1 allow build_open_flags() to return an error
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:57:09 +04:00
Al Viro
2cf0966683 make SYSCALL_DEFINE<n>-generated wrappers do asmlinkage_protect
... and switch i386 to HAVE_SYSCALL_WRAPPERS, killing open-coded
uses of asmlinkage_protect() in a bunch of syscalls.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-03 22:58:33 -05:00
Al Viro
4a0fd5bf0f teach SYSCALL_DEFINE<n> how to deal with long long/unsigned long long
... and convert a bunch of SYSCALL_DEFINE ones to SYSCALL_DEFINE<n>,
killing the boilerplate crap around them.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-03 22:46:22 -05:00
Linus Torvalds
56a79b7b02 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull  more VFS bits from Al Viro:
 "Unfortunately, it looks like xattr series will have to wait until the
  next cycle ;-/

  This pile contains 9p cleanups and fixes (races in v9fs_fid_add()
  etc), fixup for nommu breakage in shmem.c, several cleanups and a bit
  more file_inode() work"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  constify path_get/path_put and fs_struct.c stuff
  fix nommu breakage in shmem.c
  cache the value of file_inode() in struct file
  9p: if v9fs_fid_lookup() gets to asking server, it'd better have hashed dentry
  9p: make sure ->lookup() adds fid to the right dentry
  9p: untangle ->lookup() a bit
  9p: double iput() in ->lookup() if d_materialise_unique() fails
  9p: v9fs_fid_add() can't fail now
  v9fs: get rid of v9fs_dentry
  9p: turn fid->dlist into hlist
  9p: don't bother with private lock in ->d_fsdata; dentry->d_lock will do just fine
  more file_inode() open-coded instances
  selinux: opened file can't have NULL or negative ->f_path.dentry

(In the meantime, the hlist traversal macros have changed, so this
required a semantic conflict fixup for the newly hlistified fid->dlist)
2013-03-03 13:23:03 -08:00
Linus Torvalds
14cc0b55b7 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
Pull signal/compat fixes from Al Viro:
 "Fixes for several regressions introduced in the last signal.git pile,
  along with fixing bugs in truncate and ftruncate compat (on just about
  anything biarch at least one of those two had been done wrong)."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
  compat: restore timerfd settime and gettime compat syscalls
  [regression] braino in "sparc: convert to ksignal"
  fix compat truncate/ftruncate
  switch lseek to COMPAT_SYSCALL_DEFINE
  lseek() and truncate() on sparc really need sign extension
2013-03-02 08:34:06 -08:00
Al Viro
dd37978c50 cache the value of file_inode() in struct file
Note that this thing does *not* contribute to inode refcount;
it's pinned down by dentry.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-03-01 19:48:30 -05:00
Al Viro
21d206819a get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-26 02:46:11 -05:00
Al Viro
3f6d078d4a fix compat truncate/ftruncate
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-25 09:24:55 -05:00
Al Viro
1afc99beaf propagate error from get_empty_filp() to its callers
Based on parts from Anatol's patch (the rest is the next commit).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22 23:31:32 -05:00
Al Viro
496ad9aa8e new helper: file_inode(file)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22 23:31:31 -05:00
Jeff Layton
99a5df37a0 vfs: make fchownat retry once on ESTALE errors
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20 18:50:07 -05:00
Jeff Layton
14ff690c0f vfs: make fchmodat retry once on ESTALE errors
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20 18:50:07 -05:00
Jeff Layton
2771261ec5 vfs: have chroot retry once on ESTALE error
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20 18:50:06 -05:00
Jeff Layton
0291c0a551 vfs: have chdir retry lookup and call once on ESTALE error
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20 18:50:06 -05:00
Jeff Layton
87fa55952b vfs: have faccessat retry once on an ESTALE error
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20 18:50:05 -05:00
Jeff Layton
48f7530d3f vfs: have do_sys_truncate retry once on an ESTALE error
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20 18:50:05 -05:00
David Howells
a02de96085 VFS: Make more complete truncate operation available to CacheFiles
Make a more complete truncate operation available to CacheFiles (including
security checks and suchlike) so that it can use this to clear invalidated
cache files.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
2012-12-20 22:05:41 +00:00
Eric W. Biederman
a85fb273c9 vfs: Allow chroot if you have CAP_SYS_CHROOT in your user namespace
Once you are confined to a user namespace applications can not gain
privilege and escape the user namespace so there is no longer a reason
to restrict chroot.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-11-19 05:59:17 -08:00
Jeff Layton
669abf4e55 vfs: make path_openat take a struct filename pointer
...and fix up the callers. For do_file_open_root, just declare a
struct filename on the stack and fill out the .name field. For
do_filp_open, make it also take a struct filename pointer, and fix up its
callers to call it appropriately.

For filp_open, add a variant that takes a struct filename pointer and turn
filp_open into a wrapper around it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12 20:15:09 -04:00
Jeff Layton
91a27b2a75 vfs: define struct filename and have getname() return it
getname() is intended to copy pathname strings from userspace into a
kernel buffer. The result is just a string in kernel space. It would
however be quite helpful to be able to attach some ancillary info to
the string.

For instance, we could attach some audit-related info to reduce the
amount of audit-related processing needed. When auditing is enabled,
we could also call getname() on the string more than once and not
need to recopy it from userspace.

This patchset converts the getname()/putname() interfaces to return
a struct instead of a string. For now, the struct just tracks the
string in kernel space and the original userland pointer for it.

Later, we'll add other information to the struct as it becomes
convenient.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12 20:14:55 -04:00
Jeff Layton
bfcec70874 audit: set the name_len in audit_inode for parent lookups
Currently, this gets set mostly by happenstance when we call into
audit_inode_child. While that might be a little more efficient, it seems
wrong. If the syscall ends up failing before audit_inode_child ever gets
called, then you'll have an audit_names record that shows the full path
but has the parent inode info attached.

Fix this by passing in a parent flag when we call audit_inode that gets
set to the value of LOOKUP_PARENT. We can then fix up the pathname for
the audit entry correctly from the get-go.

While we're at it, clean up the no-op macro for audit_inode in the
!CONFIG_AUDITSYSCALL case.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-12 00:32:01 -04:00
Linus Torvalds
aab174f0df Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs update from Al Viro:

 - big one - consolidation of descriptor-related logics; almost all of
   that is moved to fs/file.c

   (BTW, I'm seriously tempted to rename the result to fd.c.  As it is,
   we have a situation when file_table.c is about handling of struct
   file and file.c is about handling of descriptor tables; the reasons
   are historical - file_table.c used to be about a static array of
   struct file we used to have way back).

   A lot of stray ends got cleaned up and converted to saner primitives,
   disgusting mess in android/binder.c is still disgusting, but at least
   doesn't poke so much in descriptor table guts anymore.  A bunch of
   relatively minor races got fixed in process, plus an ext4 struct file
   leak.

 - related thing - fget_light() partially unuglified; see fdget() in
   there (and yes, it generates the code as good as we used to have).

 - also related - bits of Cyrill's procfs stuff that got entangled into
   that work; _not_ all of it, just the initial move to fs/proc/fd.c and
   switch of fdinfo to seq_file.

 - Alex's fs/coredump.c spiltoff - the same story, had been easier to
   take that commit than mess with conflicts.  The rest is a separate
   pile, this was just a mechanical code movement.

 - a few misc patches all over the place.  Not all for this cycle,
   there'll be more (and quite a few currently sit in akpm's tree)."

Fix up trivial conflicts in the android binder driver, and some fairly
simple conflicts due to two different changes to the sock_alloc_file()
interface ("take descriptor handling from sock_alloc_file() to callers"
vs "net: Providing protocol type via system.sockprotoname xattr of
/proc/PID/fd entries" adding a dentry name to the socket)

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (72 commits)
  MAX_LFS_FILESIZE should be a loff_t
  compat: fs: Generic compat_sys_sendfile implementation
  fs: push rcu_barrier() from deactivate_locked_super() to filesystems
  btrfs: reada_extent doesn't need kref for refcount
  coredump: move core dump functionality into its own file
  coredump: prevent double-free on an error path in core dumper
  usb/gadget: fix misannotations
  fcntl: fix misannotations
  ceph: don't abuse d_delete() on failure exits
  hypfs: ->d_parent is never NULL or negative
  vfs: delete surplus inode NULL check
  switch simple cases of fget_light to fdget
  new helpers: fdget()/fdput()
  switch o2hb_region_dev_write() to fget_light()
  proc_map_files_readdir(): don't bother with grabbing files
  make get_file() return its argument
  vhost_set_vring(): turn pollstart/pollstop into bool
  switch prctl_set_mm_exe_file() to fget_light()
  switch xfs_find_handle() to fget_light()
  switch xfs_swapext() to fget_light()
  ...
2012-10-02 20:25:04 -07:00
Linus Torvalds
437589a74b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace changes from Eric Biederman:
 "This is a mostly modest set of changes to enable basic user namespace
  support.  This allows the code to code to compile with user namespaces
  enabled and removes the assumption there is only the initial user
  namespace.  Everything is converted except for the most complex of the
  filesystems: autofs4, 9p, afs, ceph, cifs, coda, fuse, gfs2, ncpfs,
  nfs, ocfs2 and xfs as those patches need a bit more review.

  The strategy is to push kuid_t and kgid_t values are far down into
  subsystems and filesystems as reasonable.  Leaving the make_kuid and
  from_kuid operations to happen at the edge of userspace, as the values
  come off the disk, and as the values come in from the network.
  Letting compile type incompatible compile errors (present when user
  namespaces are enabled) guide me to find the issues.

  The most tricky areas have been the places where we had an implicit
  union of uid and gid values and were storing them in an unsigned int.
  Those places were converted into explicit unions.  I made certain to
  handle those places with simple trivial patches.

  Out of that work I discovered we have generic interfaces for storing
  quota by projid.  I had never heard of the project identifiers before.
  Adding full user namespace support for project identifiers accounts
  for most of the code size growth in my git tree.

  Ultimately there will be work to relax privlige checks from
  "capable(FOO)" to "ns_capable(user_ns, FOO)" where it is safe allowing
  root in a user names to do those things that today we only forbid to
  non-root users because it will confuse suid root applications.

  While I was pushing kuid_t and kgid_t changes deep into the audit code
  I made a few other cleanups.  I capitalized on the fact we process
  netlink messages in the context of the message sender.  I removed
  usage of NETLINK_CRED, and started directly using current->tty.

  Some of these patches have also made it into maintainer trees, with no
  problems from identical code from different trees showing up in
  linux-next.

  After reading through all of this code I feel like I might be able to
  win a game of kernel trivial pursuit."

Fix up some fairly trivial conflicts in netfilter uid/git logging code.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (107 commits)
  userns: Convert the ufs filesystem to use kuid/kgid where appropriate
  userns: Convert the udf filesystem to use kuid/kgid where appropriate
  userns: Convert ubifs to use kuid/kgid
  userns: Convert squashfs to use kuid/kgid where appropriate
  userns: Convert reiserfs to use kuid and kgid where appropriate
  userns: Convert jfs to use kuid/kgid where appropriate
  userns: Convert jffs2 to use kuid and kgid where appropriate
  userns: Convert hpfs to use kuid and kgid where appropriate
  userns: Convert btrfs to use kuid/kgid where appropriate
  userns: Convert bfs to use kuid/kgid where appropriate
  userns: Convert affs to use kuid/kgid wherwe appropriate
  userns: On alpha modify linux_to_osf_stat to use convert from kuids and kgids
  userns: On ia64 deal with current_uid and current_gid being kuid and kgid
  userns: On ppc convert current_uid from a kuid before printing.
  userns: Convert s390 getting uid and gid system calls to use kuid and kgid
  userns: Convert s390 hypfs to use kuid and kgid where appropriate
  userns: Convert binder ipc to use kuids
  userns: Teach security_path_chown to take kuids and kgids
  userns: Add user namespace support to IMA
  userns: Convert EVM to deal with kuids and kgids in it's hmac computation
  ...
2012-10-02 11:11:09 -07:00
Al Viro
2903ff019b switch simple cases of fget_light to fdget
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26 22:20:08 -04:00
Al Viro
d6483b7a78 switch fchmod(2) to fget_light()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26 21:10:03 -04:00
Al Viro
6b48c5b207 switch fallocate(2) to fget_light()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26 21:10:03 -04:00
Al Viro
bf2965d5b5 switch ftruncate(2) to fget_light
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26 21:10:02 -04:00
Al Viro
c6f3d81115 don't leak O_CLOEXEC into ->f_flags
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26 21:10:01 -04:00
Al Viro
483ce1d4b8 take descriptor-related part of close() to file.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26 21:08:56 -04:00
Al Viro
56007cae94 move put_unused_fd() and fd_install() to fs/file.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26 21:08:55 -04:00
Eric W. Biederman
d2b31ca644 userns: Teach security_path_chown to take kuids and kgids
Don't make the security modules deal with raw user space uid and
gids instead pass in a kuid_t and a kgid_t so that security modules
only have to deal with internal kernel uids and gids.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: James Morris <james.l.morris@oracle.com>
Cc: John Johansen <john.johansen@canonical.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-09-21 03:13:25 -07:00
Miklos Szeredi
e68726ff72 vfs: canonicalize create mode in build_open_flags()
Userspace can pass weird create mode in open(2) that we canonicalize to 
"(mode & S_IALLUGO) | S_IFREG" in vfs_create().

The problem is that we use the uncanonicalized mode before calling vfs_create()
with unforseen consequences.

So do the canonicalization early in build_open_flags().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
CC: stable@vger.kernel.org
2012-08-15 13:01:24 +02:00
Al Viro
fe7c80518e missed mnt_drop_write() in do_dentry_open()
This one ought to be __mnt_drop_write(), to match __mnt_want_write()
in the beginning...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-04 12:15:41 +04:00
Jan Kara
14da920014 fs: Protect write paths by sb_start_write - sb_end_write
There are several entry points which dirty pages in a filesystem.  mmap
(handled by block_page_mkwrite()), buffered write (handled by
__generic_file_aio_write()), splice write (generic_file_splice_write),
truncate, and fallocate (these can dirty last partial page - handled inside
each filesystem separately). Protect these places with sb_start_write() and
sb_end_write().

->page_mkwrite() calls are particularly complex since they are called with
mmap_sem held and thus we cannot use standard sb_start_write() due to lock
ordering constraints. We solve the problem by using a special freeze protection
sb_start_pagefault() which ranks below mmap_sem.

BugLink: https://bugs.launchpad.net/bugs/897421
Tested-by: Kamal Mostafa <kamal@canonical.com>
Tested-by: Peter M. Petrakis <peter.petrakis@canonical.com>
Tested-by: Dann Frazier <dann.frazier@canonical.com>
Tested-by: Massimo Morana <massimo.morana@canonical.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-31 09:45:47 +04:00
Jan Kara
eb04c28288 fs: Add freezing handling to mnt_want_write() / mnt_drop_write()
Most of places where we want freeze protection coincides with the places where
we also have remount-ro protection. So make mnt_want_write() and
mnt_drop_write() (and their _file alternative) prevent freezing as well.
For the few cases that are really interested only in remount-ro protection
provide new function variants.

BugLink: https://bugs.launchpad.net/bugs/897421
Tested-by: Kamal Mostafa <kamal@canonical.com>
Tested-by: Peter M. Petrakis <peter.petrakis@canonical.com>
Tested-by: Dann Frazier <dann.frazier@canonical.com>
Tested-by: Massimo Morana <massimo.morana@canonical.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-31 09:40:38 +04:00
Al Viro
b5bcdda327 take grabbing f->f_path to do_dentry_open()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-29 21:24:18 +04:00
Al Viro
765927b2d5 switch dentry_open() to struct path, make it grab references itself
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-23 00:01:29 +04:00
David Howells
55e4def0a6 VFS: Make chown() and lchown() call fchownat()
Make the chown() and lchown() syscalls jump to the fchownat() syscall with the
appropriate extra arguments.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:35:54 +04:00
Al Viro
c3c4f69424 do_dentry_open(): close the race with mark_files_ro() in failure exit
we want to take it out of mark_files_ro() reach *before* we start
checking if we ought to drop write access.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:35:50 +04:00
Al Viro
02e5180d99 do_dentry_open(): take initialization of file->f_path to caller
... and get rid of a couple of arguments and a pointless reassignment
in finish_open() case.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:54 +04:00
Al Viro
2a027e7a18 fold __dentry_open() into its sole caller
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:52 +04:00
Al Viro
96b7e579ad switch do_dentry_open() to returning int
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:49 +04:00
Al Viro
e45198a6ac make finish_no_open() return int
namely, 1 ;-)  That's what we want to return from ->atomic_open()
instances after finish_no_open().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:45 +04:00
Al Viro
30d9049474 kill struct opendata
Just pass struct file *.  Methods are happier that way...
There's no need to return struct file * from finish_open() now,
so let it return int.  Next: saner prototypes for parts in
namei.c

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:39 +04:00
Al Viro
a4a3bdd778 kill opendata->{mnt,dentry}
->filp->f_path is there for purpose...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:37 +04:00
Al Viro
3d8a00d209 don't modify od->filp at all
make put_filp() conditional on flag set by finish_open()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:33 +04:00
Al Viro
47237687d7 ->atomic_open() prototype change - pass int * instead of bool *
... and let finish_open() report having opened the file via that sucker.
Next step: don't modify od->filp at all.

[AV: FILE_CREATE was already used by cifs; Miklos' fix folded]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:31 +04:00
Miklos Szeredi
015c3bbcd8 vfs: remove open intents from nameidata
All users of open intents have been converted to use ->atomic_{open,create}.

This patch gets rid of nd->intent.open and related infrastructure.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:18 +04:00
Miklos Szeredi
d18e9008c3 vfs: add i_op->atomic_open()
Add a new inode operation which is called on the last component of an open.
Using this the filesystem can look up, possibly create and open the file in one
atomic operation.  If it cannot perform this (e.g. the file type turned out to
be wrong) it may signal this by returning NULL instead of an open struct file
pointer.

i_op->atomic_open() is only called if the last component is negative or needs
lookup.  Handling cached positive dentries here doesn't add much value: these
can be opened using f_op->open().  If the cached file turns out to be invalid,
the open can be retried, this time using ->atomic_open() with a fresh dentry.

For now leave the old way of using open intents in lookup and revalidate in
place.  This will be removed once all the users are converted.

David Howells noticed that if ->atomic_open() opens the file but does not create
it, handle_truncate() will be called on it even if it is not a regular file.
Fix this by checking the file type in this case too.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:04 +04:00
Linus Torvalds
332a2e1244 vfs: make O_PATH file descriptors usable for 'fchdir()'
We already use them for openat() and friends, but fchdir() also wants to
be able to use O_PATH file descriptors.  This should make it comparable
to the O_SEARCH of Solaris.  In particular, O_PATH allows you to access
(not-quite-open) a directory you don't have read persmission to, only
execute permission.

Noticed during development of multithread support for ksh93.

Reported-by: ольга крыжановская <olga.kryzhanovska@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@kernel.org    # O_PATH introduced in 3.0+
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-07 17:19:02 -07:00
Miklos Szeredi
50ee93afca vfs: nameidata_to_filp(): don't throw away file on error
If open fails, don't put the file.  This allows it to be reused if open needs to
be retried.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:12:01 -04:00
Miklos Szeredi
91daee988d vfs: nameidata_to_filp(): inline __dentry_open()
Copy __dentry_open() into nameidata_to_filp().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:12:01 -04:00
Miklos Szeredi
78f71eff3c vfs: do_dentry_open(): don't put filp
Move put_filp() out to __dentry_open(), the only caller now.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:12:00 -04:00
Miklos Szeredi
90ad1a8ecb vfs: split __dentry_open()
Split __dentry_open() into two functions:

  do_dentry_open() - does most of the actual work, doesn't put file on failure
  open_check_o_direct() - after a successful open, checks direct_IO method

This will allow i_op->atomic_open to do just the file initialization and leave
the direct_IO checking to the VFS.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01 12:12:00 -04:00
Linus Torvalds
644473e9c6 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace enhancements from Eric Biederman:
 "This is a course correction for the user namespace, so that we can
  reach an inexpensive, maintainable, and reasonably complete
  implementation.

  Highlights:
   - Config guards make it impossible to enable the user namespace and
     code that has not been converted to be user namespace safe.

   - Use of the new kuid_t type ensures the if you somehow get past the
     config guards the kernel will encounter type errors if you enable
     user namespaces and attempt to compile in code whose permission
     checks have not been updated to be user namespace safe.

   - All uids from child user namespaces are mapped into the initial
     user namespace before they are processed.  Removing the need to add
     an additional check to see if the user namespace of the compared
     uids remains the same.

   - With the user namespaces compiled out the performance is as good or
     better than it is today.

   - For most operations absolutely nothing changes performance or
     operationally with the user namespace enabled.

   - The worst case performance I could come up with was timing 1
     billion cache cold stat operations with the user namespace code
     enabled.  This went from 156s to 164s on my laptop (or 156ns to
     164ns per stat operation).

   - (uid_t)-1 and (gid_t)-1 are reserved as an internal error value.
     Most uid/gid setting system calls treat these value specially
     anyway so attempting to use -1 as a uid would likely cause
     entertaining failures in userspace.

   - If setuid is called with a uid that can not be mapped setuid fails.
     I have looked at sendmail, login, ssh and every other program I
     could think of that would call setuid and they all check for and
     handle the case where setuid fails.

   - If stat or a similar system call is called from a context in which
     we can not map a uid we lie and return overflowuid.  The LFS
     experience suggests not lying and returning an error code might be
     better, but the historical precedent with uids is different and I
     can not think of anything that would break by lying about a uid we
     can't map.

   - Capabilities are localized to the current user namespace making it
     safe to give the initial user in a user namespace all capabilities.

  My git tree covers all of the modifications needed to convert the core
  kernel and enough changes to make a system bootable to runlevel 1."

Fix up trivial conflicts due to nearby independent changes in fs/stat.c

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits)
  userns:  Silence silly gcc warning.
  cred: use correct cred accessor with regards to rcu read lock
  userns: Convert the move_pages, and migrate_pages permission checks to use uid_eq
  userns: Convert cgroup permission checks to use uid_eq
  userns: Convert tmpfs to use kuid and kgid where appropriate
  userns: Convert sysfs to use kgid/kuid where appropriate
  userns: Convert sysctl permission checks to use kuid and kgids.
  userns: Convert proc to use kuid/kgid where appropriate
  userns: Convert ext4 to user kuid/kgid where appropriate
  userns: Convert ext3 to use kuid/kgid where appropriate
  userns: Convert ext2 to use kuid/kgid where appropriate.
  userns: Convert devpts to use kuid/kgid where appropriate
  userns: Convert binary formats to use kuid/kgid where appropriate
  userns: Add negative depends on entries to avoid building code that is userns unsafe
  userns: signal remove unnecessary map_cred_ns
  userns: Teach inode_capable to understand inodes whose uids map to other namespaces.
  userns: Fail exec for suid and sgid binaries with ids outside our user namespace.
  userns: Convert stat to return values mapped from kuids and kgids
  userns: Convert user specfied uids and gids in chown into kuids and kgid
  userns: Use uid_eq gid_eq helpers when comparing kuids and kgids in the vfs
  ...
2012-05-23 17:42:39 -07:00
Eric W. Biederman
52137abe18 userns: Convert user specfied uids and gids in chown into kuids and kgid
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-05-03 03:29:34 -07:00
Eric W. Biederman
18815a1808 userns: Convert capabilities related permsion checks
- Use uid_eq when comparing kuids
  Use gid_eq when comparing kgids
- Use make_kuid(user_ns, 0) to talk about the user_namespace root uid

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-05-03 03:28:40 -07:00