Commit Graph

47383 Commits

Author SHA1 Message Date
Jeff Layton
f698cccbc8 ufs: fix function declaration for ufs_truncate_blocks
sparse says:

    fs/ufs/inode.c:1195:6: warning: symbol 'ufs_truncate_blocks' was not declared. Should it be static?

Note that the forward declaration in the file is already marked static.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-22 23:03:41 -05:00
Aleksa Sarai
613cc2b6f2 fs: exec: apply CLOEXEC before changing dumpable task flags
If you have a process that has set itself to be non-dumpable, and it
then undergoes exec(2), any CLOEXEC file descriptors it has open are
"exposed" during a race window between the dumpable flags of the process
being reset for exec(2) and CLOEXEC being applied to the file
descriptors. This can be exploited by a process by attempting to access
/proc/<pid>/fd/... during this window, without requiring CAP_SYS_PTRACE.

The race in question is after set_dumpable has been (for get_link,
though the trace is basically the same for readlink):

[vfs]
-> proc_pid_link_inode_operations.get_link
   -> proc_pid_get_link
      -> proc_fd_access_allowed
         -> ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);

Which will return 0, during the race window and CLOEXEC file descriptors
will still be open during this window because do_close_on_exec has not
been called yet. As a result, the ordering of these calls should be
reversed to avoid this race window.

This is of particular concern to container runtimes, where joining a
PID namespace with file descriptors referring to the host filesystem
can result in security issues (since PRCTL_SET_DUMPABLE doesn't protect
against access of CLOEXEC file descriptors -- file descriptors which may
reference filesystem objects the container shouldn't have access to).

Cc: dev@opencontainers.org
Cc: <stable@vger.kernel.org> # v3.2+
Reported-by: Michael Crosby <crosbymichael@gmail.com>
Signed-off-by: Aleksa Sarai <asarai@suse.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-22 23:03:41 -05:00
Tomasz Majchrzak
e522751d60 seq_file: reset iterator to first record for zero offset
If kernfs file is empty on a first read, successive read operations
using the same file descriptor will return no data, even when data is
available. Default kernfs 'seq_next' implementation advances iterator
position even when next object is not there. Kernfs 'seq_start' for
following requests will not return iterator as position is already on
the second object.

This defect doesn't allow to monitor badblocks sysfs files from MD raid.
They are initially empty but if data appears at some stage, userspace is
not able to read it.

Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-22 23:03:06 -05:00
Darrick J. Wong
22725ce4e4 vfs: fix isize/pos/len checks for reflink & dedupe
Strengthen the checking of pos/len vs. i_size, clarify the return values
for the clone prep function, and remove pointless code.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-22 23:00:23 -05:00
Al Viro
c00d2c7e89 move aio compat to fs/aio.c
... and fix the minor buglet in compat io_submit() - native one
kills ioctx as cleanup when put_user() fails.  Get rid of
bogus compat_... in !CONFIG_AIO case, while we are at it - they
should simply fail with ENOSYS, same as for native counterparts.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-22 22:58:37 -05:00
Linus Torvalds
e93b1cc8a8 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull quota, fsnotify and ext2 updates from Jan Kara:
 "Changes to locking of some quota operations from dedicated quota mutex
  to s_umount semaphore, a fsnotify fix and a simple ext2 fix"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  quota: Fix bogus warning in dquot_disable()
  fsnotify: Fix possible use-after-free in inode iteration on umount
  ext2: reject inodes with negative size
  quota: Remove dqonoff_mutex
  ocfs2: Use s_umount for quota recovery protection
  quota: Remove dqonoff_mutex from dquot_scan_active()
  ocfs2: Protect periodic quota syncing with s_umount semaphore
  quota: Use s_umount protection for quota operations
  quota: Hold s_umount in exclusive mode when enabling / disabling quotas
  fs: Provide function to get superblock with exclusive s_umount
2016-12-19 08:23:53 -08:00
Jan Kara
2700e6067c quota: Fix bogus warning in dquot_disable()
dquot_disable() was warning when sb_has_quota_loaded() was true when
invalidating page cache for quota files. The thinking behind this
warning was that we must have raced with somebody else turning quotas on
and this should not happen because all places modifying quota state must
hold s_umount exclusively now. However sb_has_quota_loaded() can be also
true at this point when we are just suspending quotas on remount
read-only. Just restore the behavior to situation before commit
c3b004460d ("quota: Remove dqonoff_mutex") which introduced the
warning.

The code in dquot_disable() can be further simplified with the new
locking of quota state changes however let's leave that to a separate
commit that can get more testing exposure.

Fixes: c3b004460d
Signed-off-by: Jan Kara <jack@suse.cz>
2016-12-19 14:01:39 +01:00
Linus Torvalds
231753ef78 Merge uncontroversial parts of branch 'readlink' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull partial readlink cleanups from Miklos Szeredi.

This is the uncontroversial part of the readlink cleanup patch-set that
simplifies the default readlink handling.

Miklos and Al are still discussing the rest of the series.

* git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  vfs: make generic_readlink() static
  vfs: remove ".readlink = generic_readlink" assignments
  vfs: default to generic_readlink()
  vfs: replace calling i_op->readlink with vfs_readlink()
  proc/self: use generic_readlink
  ecryptfs: use vfs_get_link()
  bad_inode: add missing i_op initializers
2016-12-17 19:16:12 -08:00
Linus Torvalds
0110c350c8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro:
 "In this pile:

   - autofs-namespace series
   - dedupe stuff
   - more struct path constification"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (40 commits)
  ocfs2: implement the VFS clone_range, copy_range, and dedupe_range features
  ocfs2: charge quota for reflinked blocks
  ocfs2: fix bad pointer cast
  ocfs2: always unlock when completing dio writes
  ocfs2: don't eat io errors during _dio_end_io_write
  ocfs2: budget for extent tree splits when adding refcount flag
  ocfs2: prohibit refcounted swapfiles
  ocfs2: add newlines to some error messages
  ocfs2: convert inode refcount test to a helper
  simple_write_end(): don't zero in short copy into uptodate
  exofs: don't mess with simple_write_{begin,end}
  9p: saner ->write_end() on failing copy into non-uptodate page
  fix gfs2_stuffed_write_end() on short copies
  fix ceph_write_end()
  nfs_write_end(): fix handling of short copies
  vfs: refactor clone/dedupe_file_range common functions
  fs: try to clone files first in vfs_copy_file_range
  vfs: misc struct path constification
  namespace.c: constify struct path passed to a bunch of primitives
  quota: constify struct path in quota_on
  ...
2016-12-17 18:44:00 -08:00
Al Viro
9763f7a4a5 Merge branch 'work.autofs' into for-linus
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-16 16:34:52 -05:00
Al Viro
3c55d6bcfe Merge remote-tracking branch 'djwong/ocfs2-vfs-reflink-6' into for-linus 2016-12-16 16:21:05 -05:00
Al Viro
4da00fd1b9 Merge branch 'work.write_end' into for-linus 2016-12-16 16:19:49 -05:00
Linus Torvalds
59331c215d A varied set of changes:
- a large rework of cephx auth code to cope with CONFIG_VMAP_STACK
   (myself).  Also fixed a deadlock caused by a bogus allocation on the
   writeback path and authorize reply verification.
 
 - a fix for long stalls during fsync (Jeff Layton).  The client now
   has a way to force the MDS log flush, leading to ~100x speedups in
   some synthetic tests.
 
 - a new [no]require_active_mds mount option (Zheng Yan).  On mount, we
   will now check whether any of the MDSes are available and bail rather
   than block if none are.  This check can be avoided by specifying the
   "no" option.
 
 - a couple of MDS cap handling fixes and a few assorted patches
   throughout.
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Merge tag 'ceph-for-4.10-rc1' of git://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:
 "A varied set of changes:

   - a large rework of cephx auth code to cope with CONFIG_VMAP_STACK
     (myself). Also fixed a deadlock caused by a bogus allocation on the
     writeback path and authorize reply verification.

   - a fix for long stalls during fsync (Jeff Layton). The client now
     has a way to force the MDS log flush, leading to ~100x speedups in
     some synthetic tests.

   - a new [no]require_active_mds mount option (Zheng Yan).

     On mount, we will now check whether any of the MDSes are available
     and bail rather than block if none are. This check can be avoided
     by specifying the "no" option.

   - a couple of MDS cap handling fixes and a few assorted patches
     throughout"

* tag 'ceph-for-4.10-rc1' of git://github.com/ceph/ceph-client: (32 commits)
  libceph: remove now unused finish_request() wrapper
  libceph: always signal completion when done
  ceph: avoid creating orphan object when checking pool permission
  ceph: properly set issue_seq for cap release
  ceph: add flags parameter to send_cap_msg
  ceph: update cap message struct version to 10
  ceph: define new argument structure for send_cap_msg
  ceph: move xattr initialzation before the encoding past the ceph_mds_caps
  ceph: fix minor typo in unsafe_request_wait
  ceph: record truncate size/seq for snap data writeback
  ceph: check availability of mds cluster on mount
  ceph: fix splice read for no Fc capability case
  ceph: try getting buffer capability for readahead/fadvise
  ceph: fix scheduler warning due to nested blocking
  ceph: fix printing wrong return variable in ceph_direct_read_write()
  crush: include mapper.h in mapper.c
  rbd: silence bogus -Wmaybe-uninitialized warning
  libceph: no need to drop con->mutex for ->get_authorizer()
  libceph: drop len argument of *verify_authorizer_reply()
  libceph: verify authorize reply on connect
  ...
2016-12-16 11:23:34 -08:00
Linus Torvalds
ff0f962ca3 Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs updates from Miklos Szeredi:
 "This update contains:

   - try to clone on copy-up

   - allow renaming a directory

   - split source into managable chunks

   - misc cleanups and fixes

  It does not contain the read-only fd data inconsistency fix, which Al
  didn't like. I'll leave that to the next year..."

* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: (36 commits)
  ovl: fix reStructuredText syntax errors in documentation
  ovl: fix return value of ovl_fill_super
  ovl: clean up kstat usage
  ovl: fold ovl_copy_up_truncate() into ovl_copy_up()
  ovl: create directories inside merged parent opaque
  ovl: opaque cleanup
  ovl: show redirect_dir mount option
  ovl: allow setting max size of redirect
  ovl: allow redirect_dir to default to "on"
  ovl: check for emptiness of redirect dir
  ovl: redirect on rename-dir
  ovl: lookup redirects
  ovl: consolidate lookup for underlying layers
  ovl: fix nested overlayfs mount
  ovl: check namelen
  ovl: split super.c
  ovl: use d_is_dir()
  ovl: simplify lookup
  ovl: check lower existence of rename target
  ovl: rename: simplify handling of lower/merged directory
  ...
2016-12-16 10:58:12 -08:00
Linus Torvalds
087a76d390 Merge branch 'for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "Jeff Mahoney and Dave Sterba have a really nice set of cleanups in
  here, and Christoph pitched in corrections/improvements to make btrfs
  use proper helpers for bio walking instead of doing it by hand.

  There are some key fixes as well, including some long standing bugs
  that took forever to track down in btrfs_drop_extents and during
  balance"

* 'for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (77 commits)
  btrfs: limit async_work allocation and worker func duration
  Revert "Btrfs: adjust len of writes if following a preallocated extent"
  Btrfs: don't WARN() in btrfs_transaction_abort() for IO errors
  btrfs: opencode chunk locking, remove helpers
  btrfs: remove root parameter from transaction commit/end routines
  btrfs: split btrfs_wait_marked_extents into normal and tree log functions
  btrfs: take an fs_info directly when the root is not used otherwise
  btrfs: simplify btrfs_wait_cache_io prototype
  btrfs: convert extent-tree tracepoints to use fs_info
  btrfs: root->fs_info cleanup, access fs_info->delayed_root directly
  btrfs: root->fs_info cleanup, add fs_info convenience variables
  btrfs: root->fs_info cleanup, update_block_group{,flags}
  btrfs: root->fs_info cleanup, lock/unlock_chunks
  btrfs: root->fs_info cleanup, btrfs_calc_{trans,trunc}_metadata_size
  btrfs: pull node/sector/stripe sizes out of root and into fs_info
  btrfs: root->fs_info cleanup, io_ctl_init
  btrfs: root->fs_info cleanup, use fs_info->dev_root everywhere
  btrfs: struct reada_control.root -> reada_control.fs_info
  btrfs: struct btrfsic_state->root should be an fs_info
  btrfs: alloc_reserved_file_extent trace point should use extent_root
  ...
2016-12-16 10:53:01 -08:00
Linus Torvalds
759b2656b2 The one new feature is support for a new NFSv4.2 mode_umask attribute
that makes ACL inheritance a little more useful in environments that
 default to restrictive umasks.  Requires client-side support, also on
 its way for 4.10.
 
 Other than that, miscellaneous smaller fixes and cleanup, especially to
 the server rdma code.
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Merge tag 'nfsd-4.10' of git://linux-nfs.org/~bfields/linux

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

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

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

* tag 'nfsd-4.10' of git://linux-nfs.org/~bfields/linux:
  nfsd: add support for the umask attribute
  sunrpc: use DEFINE_SPINLOCK()
  svcrdma: Further clean-up of svc_rdma_get_inv_rkey()
  svcrdma: Break up dprintk format in svc_rdma_accept()
  svcrdma: Remove unused variable in rdma_copy_tail()
  svcrdma: Remove unused variables in xprt_rdma_bc_allocate()
  svcrdma: Remove svc_rdma_op_ctxt::wc_status
  svcrdma: Remove DMA map accounting
  svcrdma: Remove BH-disabled spin locking in svc_rdma_send()
  svcrdma: Renovate sendto chunk list parsing
  svcauth_gss: Close connection when dropping an incoming message
  svcrdma: Clear xpt_bc_xps in xprt_setup_rdma_bc() error exit arm
  nfsd: constify reply_cache_stats_operations structure
  nfsd: update workqueue creation
  sunrpc: GFP_KERNEL should be GFP_NOFS in crypto code
  nfsd: catch errors in decode_fattr earlier
  nfsd: clean up supported attribute handling
  nfsd: fix error handling for clients that fail to return the layout
  nfsd: more robust allocation failure handling in nfsd_reply_cache_init
2016-12-16 10:48:28 -08:00
Linus Torvalds
9a19a6db37 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:

 - more ->d_init() stuff (work.dcache)

 - pathname resolution cleanups (work.namei)

 - a few missing iov_iter primitives - copy_from_iter_full() and
   friends. Either copy the full requested amount, advance the iterator
   and return true, or fail, return false and do _not_ advance the
   iterator. Quite a few open-coded callers converted (and became more
   readable and harder to fuck up that way) (work.iov_iter)

 - several assorted patches, the big one being logfs removal

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  logfs: remove from tree
  vfs: fix put_compat_statfs64() does not handle errors
  namei: fold should_follow_link() with the step into not-followed link
  namei: pass both WALK_GET and WALK_MORE to should_follow_link()
  namei: invert WALK_PUT logics
  namei: shift interpretation of LOOKUP_FOLLOW inside should_follow_link()
  namei: saner calling conventions for mountpoint_last()
  namei.c: get rid of user_path_parent()
  switch getfrag callbacks to ..._full() primitives
  make skb_add_data,{_nocache}() and skb_copy_to_page_nocache() advance only on success
  [iov_iter] new primitives - copy_from_iter_full() and friends
  don't open-code file_inode()
  ceph: switch to use of ->d_init()
  ceph: unify dentry_operations instances
  lustre: switch to use of ->d_init()
2016-12-16 10:24:44 -08:00
Geliang Tang
313684c48c ovl: fix return value of ovl_fill_super
If kcalloc() failed, the return value of ovl_fill_super() is -EINVAL,
not -ENOMEM. So this patch sets this value to -ENOMEM before calling
kcalloc(), and sets it back to -EINVAL after calling kcalloc().

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:57 +01:00
Al Viro
32a3d848eb ovl: clean up kstat usage
FWIW, there's a bit of abuse of struct kstat in overlayfs object
creation paths - for one thing, it ends up with a very small subset
of struct kstat (mode + rdev), for another it also needs link in
case of symlinks and ends up passing it separately.

IMO it would be better to introduce a separate object for that.

In principle, we might even lift that thing into general API and switch
 ->mkdir()/->mknod()/->symlink() to identical calling conventions.  Hell
knows, perhaps ->create() as well...

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:57 +01:00
Amir Goldstein
9aba652190 ovl: fold ovl_copy_up_truncate() into ovl_copy_up()
This removes code duplication.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:57 +01:00
Amir Goldstein
97c684cc91 ovl: create directories inside merged parent opaque
The benefit of making directories opaque on creation is that lookups can
stop short when they reach the original created directory, instead of
continue lookup the entire depth of parent directory stack.

The best case is overlay with N layers, performing lookup for first level
directory, which exists only in upper.  In that case, there will be only
one lookup instead of N.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:57 +01:00
Miklos Szeredi
5cf5b477f0 ovl: opaque cleanup
oe->opaque is set for

 a) whiteouts
 b) directories having the "trusted.overlay.opaque" xattr

Case b can be simplified, since setting the xattr always implies setting
oe->opaque.  Also once set, the opaque flag is never cleared.

Don't need to set opaque flag for non-directories.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:57 +01:00
Amir Goldstein
c5bef3a72b ovl: show redirect_dir mount option
Show the value of redirect_dir in /proc/mounts.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:57 +01:00
Miklos Szeredi
3ea22a71b6 ovl: allow setting max size of redirect
Add a module option to allow tuning the max size of absolute redirects.
Default is 256.

Size of relative redirects is naturally limited by the the underlying
filesystem's max filename length (usually 255).

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:57 +01:00
Miklos Szeredi
688ea0e5a0 ovl: allow redirect_dir to default to "on"
This patch introduces a kernel config option and a module param.  Both can
be used independently to turn the default value of redirect_dir on or off.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:57 +01:00
Amir Goldstein
d15951198e ovl: check for emptiness of redirect dir
Before introducing redirect_dir feature, the condition
!ovl_lower_positive(dentry) for a directory, implied that it is a pure
upper directory, which may be removed if empty.

Now that directory can be redirect, it is possible that upper does not
cover any lower (i.e. !ovl_lower_positive(dentry)), but the directory is a
merge (with redirected path) and maybe non empty.

Check for this case in ovl_remove_upper().

This change fixes the following test case from rename-pop-dir.py
of unionmount-testsuite:

    """Remove dir and rename old name"""
    d = ctx.non_empty_dir()
    d2 = ctx.no_dir()

    ctx.rmdir(d, err=ENOTEMPTY)
    ctx.rename(d, d2)
    ctx.rmdir(d, err=ENOENT)
    ctx.rmdir(d2, err=ENOTEMPTY)

./run --ov rename-pop-dir
/mnt/a/no_dir103: Expected error (Directory not empty) was not produced

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:57 +01:00
Miklos Szeredi
a6c6065511 ovl: redirect on rename-dir
Current code returns EXDEV when a directory would need to be copied up to
move.  We could copy up the directory tree in this case, but there's
another, simpler solution: point to old lower directory from moved upper
directory.

This is achieved with a "trusted.overlay.redirect" xattr storing the path
relative to the root of the overlay.  After such attribute has been set,
the directory can be moved without further actions required.

This is a backward incompatible feature, old kernels won't be able to
correctly mount an overlay containing redirected directories.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:56 +01:00
Miklos Szeredi
02b69b284c ovl: lookup redirects
If a directory has the "trusted.overlay.redirect" xattr, it means that the
value of the xattr should be used to find the underlying directory on the
next lower layer.

The redirect may be relative or absolute.  Absolute redirects begin with a
slash.

A relative redirect means: instead of the current dentry's name use the
value of the redirect to find the directory in the next lower
layer. Relative redirects must not contain a slash.

An absolute redirect means: look up the directory relative to the root of
the overlay using the value of the redirect in the next lower layer.

Redirects work on lower layers as well.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:56 +01:00
Miklos Szeredi
e28edc46b8 ovl: consolidate lookup for underlying layers
Use a common helper for lookup of upper and lower layers.  This paves the
way for looking up directory redirects.

No functional change.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:56 +01:00
Amir Goldstein
48fab5d7c7 ovl: fix nested overlayfs mount
When the upper overlayfs checks "trusted.overlay.*" xattr on the underlying
overlayfs mount, it gets -EPERM, which confuses the upper overlayfs.

Fix this by returning -EOPNOTSUPP instead of -EPERM from
ovl_own_xattr_get() and ovl_own_xattr_set().  This behavior is consistent
with the behavior of ovl_listxattr(), which filters out the private
overlayfs xattrs.

Note: nested overlays are deprecated.  But this change makes sense
regardless: these xattrs are private to the overlay and should always be
hidden.  Hence getting and setting them should indicate this.

[SzMi: Use EOPNOTSUPP instead of ENODATA and use it for both getting and
setting "trusted.overlay." xattrs.  This is a perfectly valid error code
for "we don't support this prefix", which is the case here.]

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:56 +01:00
Miklos Szeredi
6b2d5fe46f ovl: check namelen
We already calculate f_namelen in statfs as the maximum of the name lengths
provided by the filesystems taking part in the overlay.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:56 +01:00
Miklos Szeredi
bbb1e54dd5 ovl: split super.c
fs/overlayfs/super.c is the biggest of the overlayfs source files and it
contains various utility functions as well as the rather complicated lookup
code.  Split these parts out to separate files.

Before:

 1446 fs/overlayfs/super.c

After:

  919 fs/overlayfs/super.c
  267 fs/overlayfs/namei.c
  235 fs/overlayfs/util.c
   51 fs/overlayfs/ovl_entry.h

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:56 +01:00
Miklos Szeredi
2b8c30e9ef ovl: use d_is_dir()
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:56 +01:00
Miklos Szeredi
8ee6059c58 ovl: simplify lookup
If encountering a non-directory, then stop looking at lower layers.

In this case the oe->opaque flag is not set anymore, which doesn't matter
since existence of lower file is now checked at remove/rename time.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:56 +01:00
Miklos Szeredi
3ee23ff102 ovl: check lower existence of rename target
Check if something exists on the lower layer(s) under the target or rename
to decide if directory needs to be marked "opaque".

Marking opaque is done before the rename, and on failure the marking was
undone.  Also the opaque xattr was removed if the target didn't cover
anything.

This patch changes behavior so that removal of "opaque" is not done in
either of the above cases.  This means that directory may have the opaque
flag even if it doesn't cover anything.  However this shouldn't affect the
performance or semantics of the overalay, while simplifying the code.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:55 +01:00
Miklos Szeredi
370e55ace5 ovl: rename: simplify handling of lower/merged directory
d_is_dir() is safe to call on a negative dentry.  Use this fact to simplify
handling of the lower or merged directories.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:55 +01:00
Miklos Szeredi
38e813db61 ovl: get rid of PURE type
The remainging uses of __OVL_PATH_PURE can be replaced by
ovl_dentry_is_opaque().

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:55 +01:00
Miklos Szeredi
2aff4534b6 ovl: check lower existence when removing
Currently ovl_lookup() checks existence of lower file even if there's a
non-directory on upper (which is always opaque).  This is done so that
remove can decide whether a whiteout is needed or not.

It would be better to defer this check to unlink, since most of the time
the gathered information about opaqueness will be unused.

This adds a helper ovl_lower_positive() that checks if there's anything on
the lower layer(s).

The following patches also introduce changes to how the "opaque" attribute
is updated on directories: this attribute is added when the directory is
creted or moved over a whiteout or object covering something on the lower
layer.  However following changes will allow the attribute to remain on the
directory after being moved, even if the new location doesn't cover
anything.  Because of this, we need to check lower layers even for opaque
directories, so that whiteout is only created when necessary.

This function will later be also used to decide about marking a directory
opaque, so deal with negative dentries as well.  When dealing with
negative, it's enough to check for being a whiteout

If the dentry is positive but not upper then it also obviously needs
whiteout/opaque.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:55 +01:00
Miklos Szeredi
c412ce4983 ovl: add ovl_dentry_is_whiteout()
And use it instead of ovl_dentry_is_opaque() where appropriate.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:55 +01:00
Miklos Szeredi
99f5d08e36 ovl: don't check sticky
Since commit 07a2daab49 ("ovl: Copy up underlying inode's ->i_mode to
overlay inode") sticky checking on overlay inode is performed by the vfs,
so checking against sticky on underlying inode is not needed.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:55 +01:00
Miklos Szeredi
804032fabb ovl: don't check rename to self
This is redundant, the vfs already performed this check (and was broken,
see commit 9409e22acd ("vfs: rename: check backing inode being equal")).

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:55 +01:00
Miklos Szeredi
ca4c8a3a80 ovl: treat special files like a regular fs
No sense in opening special files on the underlying layers, they work just
as well if opened on the overlay.

Side effect is that it's no longer possible to connect one side of a pipe
opened on overlayfs with the other side opened on the underlying layer.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:55 +01:00
Miklos Szeredi
6c02cb59e6 ovl: rename ovl_rename2() to ovl_rename()
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:55 +01:00
Amir Goldstein
2ea9846649 ovl: use vfs_clone_file_range() for copy up if possible
When copying up within the same fs, try to use vfs_clone_file_range().
This is very efficient when lower and upper are on the same fs
with file reflink support. If vfs_clone_file_range() fails for any
reason, copy up falls back to the regular data copy code.

Tested correct behavior when lower and upper are on:
1. same ext4 (copy)
2. same xfs + reflink patches + mkfs.xfs (copy)
3. same xfs + reflink patches + mkfs.xfs -m reflink=1 (reflink)
4. different xfs + reflink patches + mkfs.xfs -m reflink=1 (copy)

For comparison, on my laptop, xfstest overlay/001 (copy up of large
sparse files) takes less than 1 second in the xfs reflink setup vs.
25 seconds on the rest of the setups.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:54 +01:00
Miklos Szeredi
31c3a70695 Revert "ovl: get_write_access() in truncate"
This reverts commit 03bea60409.

Commit 4d0c5ba2ff ("vfs: do get_write_access() on upper layer of
overlayfs") makes the writecount checks inside overlayfs superfluous, the
file is already copied up and write access acquired on the upper inode when
ovl_setattr is called with ATTR_SIZE.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:54 +01:00
Amir Goldstein
b335e9d994 vfs: fix vfs_clone_file_range() for overlayfs files
With overlayfs, it is wrong to compare file_inode(inode)->i_sb
of regular files with those of non-regular files, because the
former reference the real (upper/lower) sb and the latter reference
the overlayfs sb.

Move the test for same super block after the sanity tests for
clone range of directory and non-regular file.

This change fixes xfstest generic/157, which returned EXDEV instead
of EISDIR/EINVAL in the following test cases over overlayfs:

  echo "Try to reflink a dir"
  _reflink_range $testdir1/dir1 0 $testdir1/file2 0 $blksz

  echo "Try to reflink a device"
  _reflink_range $testdir1/dev1 0 $testdir1/file2 0 $blksz

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:54 +01:00
Amir Goldstein
031a072a0b vfs: call vfs_clone_file_range() under freeze protection
Move sb_start_write()/sb_end_write() out of the vfs helper and up into the
ioctl handler.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:54 +01:00
Amir Goldstein
913b86e92e vfs: allow vfs_clone_file_range() across mount points
FICLONE/FICLONERANGE ioctls return -EXDEV if src and dest
files are not on the same mount point.
Practically, clone only requires that src and dest files
are on the same file system.

Move the check for same mount point to ioctl handler and keep
only the check for same super block in the vfs helper.

A following patch is going to use the vfs_clone_file_range()
helper in overlayfs to copy up between lower and upper
mount points on the same file system.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:54 +01:00
Miklos Szeredi
3616119da4 vfs: no mnt_want_write_file() in vfs_{copy,clone}_file_range()
We've checked for file_out being opened for write.  This ensures that we
already have mnt_want_write() on target.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:54 +01:00
Miklos Szeredi
8d3e293637 Revert "vfs: rename: check backing inode being equal"
This reverts commit 9409e22acd.

Since commit 51f7e52dc9 ("ovl: share inode for hard link") there's no
need to call d_real_inode() to check two overlay inodes for equality.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-12-16 11:02:54 +01:00