Commit Graph

45804 Commits

Author SHA1 Message Date
Linus Torvalds
5c44ad6a35 Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fix from Miklos Szeredi:
 "This fixes a regression caused by the last pull request"

* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: fix workdir creation
2016-09-09 12:56:28 -07:00
Linus Torvalds
f4a9c169c2 Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "I'm not proud of how long it took me to track down that one liner in
  btrfs_sync_log(), but the good news is the patches I was trying to
  blame for these problems were actually fine (sorry Filipe)"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: introduce tickets_id to determine whether asynchronous metadata reclaim work makes progress
  btrfs: remove root_log_ctx from ctx list before btrfs_sync_log returns
  btrfs: do not decrease bytes_may_use when replaying extents
2016-09-09 12:52:31 -07:00
Chris Mason
b7f3c7d345 Merge branch 'for-chris' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.8 2016-09-07 12:55:36 -07:00
Wang Xiaoguang
ce129655c9 btrfs: introduce tickets_id to determine whether asynchronous metadata reclaim work makes progress
In btrfs_async_reclaim_metadata_space(), we use ticket's address to
determine whether asynchronous metadata reclaim work is making progress.

	ticket = list_first_entry(&space_info->tickets,
				  struct reserve_ticket, list);
	if (last_ticket == ticket) {
		flush_state++;
	} else {
		last_ticket = ticket;
		flush_state = FLUSH_DELAYED_ITEMS_NR;
		if (commit_cycles)
			commit_cycles--;
	}

But indeed it's wrong, we should not rely on local variable's address to
do this check, because addresses may be same. In my test environment, I
dd one 168MB file in a 256MB fs, found that for this file, every time
wait_reserve_ticket() called, local variable ticket's address is same,

For above codes, assume a previous ticket's address is addrA, last_ticket
is addrA. Btrfs_async_reclaim_metadata_space() finished this ticket and
wake up it, then another ticket is added, but with the same address addrA,
now last_ticket will be same to current ticket, then current ticket's flush
work will start from current flush_state, not initial FLUSH_DELAYED_ITEMS_NR,
which may result in some enospc issues(I have seen this in my test machine).

Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-06 16:31:43 +02:00
Chris Mason
cbd60aa7cd Btrfs: remove root_log_ctx from ctx list before btrfs_sync_log returns
We use a btrfs_log_ctx structure to pass information into the
tree log commit, and get error values out.  It gets added to a per
log-transaction list which we walk when things go bad.

Commit d1433debe added an optimization to skip waiting for the log
commit, but didn't take root_log_ctx out of the list.  This
patch makes sure we remove things before exiting.

Signed-off-by: Chris Mason <clm@fb.com>
Fixes: d1433debe7
cc: stable@vger.kernel.org # 3.15+
2016-09-06 05:57:25 -07:00
Wang Xiaoguang
ed7a694839 btrfs: do not decrease bytes_may_use when replaying extents
When replaying extents, there is no need to update bytes_may_use
in btrfs_alloc_logged_file_extent(), otherwise it'll trigger a
WARN_ON about bytes_may_use.

Fixes: ("btrfs: update btrfs_space_info's bytes_may_use timely")
Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-05 17:40:41 +02:00
Nicolas Iooss
0f5aa88a7b ceph: do not modify fi->frag in need_reset_readdir()
Commit f3c4ebe65e ("ceph: using hash value to compose dentry offset")
modified "if (fpos_frag(new_pos) != fi->frag)" to "if (fi->frag |=
fpos_frag(new_pos))" in need_reset_readdir(), thus replacing a
comparison operator with an assignment one.

This looks like a typo which is reported by clang when building the
kernel with some warning flags:

    fs/ceph/dir.c:600:22: error: using the result of an assignment as a
    condition without parentheses [-Werror,-Wparentheses]
            } else if (fi->frag |= fpos_frag(new_pos)) {
                       ~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
    fs/ceph/dir.c:600:22: note: place parentheses around the assignment
    to silence this warning
            } else if (fi->frag |= fpos_frag(new_pos)) {
                                ^
                       (                             )
    fs/ceph/dir.c:600:22: note: use '!=' to turn this compound
    assignment into an inequality comparison
            } else if (fi->frag |= fpos_frag(new_pos)) {
                                ^~
                                !=

Fixes: f3c4ebe65e ("ceph: using hash value to compose dentry offset")
Signed-off-by: Nicolas Iooss <nicolas.iooss_linux@m4x.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
2016-09-05 14:30:35 +02:00
Miklos Szeredi
e1ff3dd1ae ovl: fix workdir creation
Workdir creation fails in latest kernel.

Fix by allowing EOPNOTSUPP as a valid return value from
vfs_removexattr(XATTR_NAME_POSIX_ACL_*).  Upper filesystem may not support
ACL and still be perfectly able to support overlayfs.

Reported-by: Martin Ziegler <ziegler@uni-freiburg.de>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: c11b9fdd6a ("ovl: remove posix_acl_default from workdir")
Cc: <stable@vger.kernel.org>
2016-09-05 13:55:20 +02:00
Linus Torvalds
4b30b6d126 Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "I'm still prepping a set of fixes for btrfs fsync, just nailing down a
  hard to trigger memory corruption.  For now, these are tested and ready."

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: fix one bug that process may endlessly wait for ticket in wait_reserve_ticket()
  Btrfs: fix endless loop in balancing block groups
  Btrfs: kill invalid ASSERT() in process_all_refs()
2016-09-03 12:40:45 -07:00
Linus Torvalds
41488202f1 Driver core fixes for 4.8-rc5
Here are 3 small fixes for 4.8-rc5.
 
 One for sysfs, one for kernfs, and one documentation fix, all for
 reported issues.  All of these have been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fixes from Greg KH:
 "Here are three small fixes for 4.8-rc5.

  One for sysfs, one for kernfs, and one documentation fix, all for
  reported issues.  All of these have been in linux-next for a while"

* tag 'driver-core-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  sysfs: correctly handle read offset on PREALLOC attrs
  documentation: drivers/core/of: fix name of of_node symlink
  kernfs: don't depend on d_find_any_alias() when generating notifications
2016-09-03 11:36:55 -07:00
Linus Torvalds
3e423945ea devpts: return NULL pts 'priv' entry for non-devpts nodes
In commit 8ead9dd547 ("devpts: more pty driver interface cleanups") I
made devpts_get_priv() just return the dentry->fs_data directly.  And
because I thought it wouldn't happen, I added a warning if you ever saw
a pts node that wasn't on devpts.

And no, that warning never triggered under any actual real use, but you
can trigger it by creating nonsensical pts nodes by hand.

So just revert the warning, and make devpts_get_priv() return NULL for
that case like it used to.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: stable@vger.kernel.org # 4.6+
Cc: Eric W Biederman" <ebiederm@xmission.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-09-03 11:02:50 -07:00
Linus Torvalds
f28929ba36 Merge branch 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs fixes from Miklos Szeredi:
 "Most of this is regression fixes for posix acl behavior introduced in
  4.8-rc1 (these were caught by the pjd-fstest suite).  The are also
  miscellaneous fixes marked as stable material and cleanups.

  Other than overlayfs code, it touches <linux/fs.h> to add a constant
  with which to disable posix acl caching.  No changes needed to the
  actual caching code, it automatically does the right thing, although
  later we may want to optimize this case.

  I'm now testing overlayfs with the following test suites to catch
  regressions:

   - unionmount-testsuite
   - xfstests
   - pjd-fstest"

* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: update doc
  ovl: listxattr: use strnlen()
  ovl: Switch to generic_getxattr
  ovl: copyattr after setting POSIX ACL
  ovl: Switch to generic_removexattr
  ovl: Get rid of ovl_xattr_noacl_handlers array
  ovl: Fix OVL_XATTR_PREFIX
  ovl: fix spelling mistake: "directries" -> "directories"
  ovl: don't cache acl on overlay layer
  ovl: use cached acl on underlying layer
  ovl: proper cleanup of workdir
  ovl: remove posix_acl_default from workdir
  ovl: handle umask and posix_acl_default correctly on creation
  ovl: don't copy up opaqueness
2016-09-02 09:32:15 -07:00
Linus Torvalds
511a8cdb65 Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit
Pull audit fixes from Paul Moore:
 "Two small patches to fix some bugs with the audit-by-executable
  functionality we introduced back in v4.3 (both patches are marked
  for the stable folks)"

* 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit:
  audit: fix exe_file access in audit_exe_compare
  mm: introduce get_task_exe_file
2016-09-01 15:55:56 -07:00
Linus Torvalds
7d1ce606a3 xfs: updates for 4.8-rc5
Changes in this update:
 o iomap FIEMAP_EXTENT_MERGED usage fix
 o additional mount-time feature restrictions
 o rmap btree query fixes
 o freeze/unmount io completion workqueue fix
 o memory corruption fix for deferred operations handling
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Merge tag 'xfs-iomap-for-linus-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs

Pull xfs and iomap fixes from Dave Chinner:
 "Most of these changes are small regression fixes that address problems
  introduced in the 4.8-rc1 window.  The two fixes that aren't (IO
  completion fix and superblock inprogress check) are fixes for problems
  introduced some time ago and need to be pushed back to stable kernels.

  Changes in this update:
   - iomap FIEMAP_EXTENT_MERGED usage fix
   - additional mount-time feature restrictions
   - rmap btree query fixes
   - freeze/unmount io completion workqueue fix
   - memory corruption fix for deferred operations handling"

* tag 'xfs-iomap-for-linus-4.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs:
  xfs: track log done items directly in the deferred pending work item
  iomap: don't set FIEMAP_EXTENT_MERGED for extent based filesystems
  xfs: prevent dropping ioend completions during buftarg wait
  xfs: fix superblock inprogress check
  xfs: simple btree query range should look right if LE lookup fails
  xfs: fix some key handling problems in _btree_simple_query_range
  xfs: don't log the entire end of the AGF
  xfs: disallow mounting of realtime + rmap filesystems
  xfs: don't perform lookups on zero-height btrees
2016-09-01 15:33:16 -07:00
Wang Xiaoguang
e0af24849e btrfs: fix one bug that process may endlessly wait for ticket in wait_reserve_ticket()
If can_overcommit() in btrfs_calc_reclaim_metadata_size() returns true,
btrfs_async_reclaim_metadata_space() will not reclaim metadata space, just
return directly and also forget to wake up process which are waiting for
their tickets, so these processes will wait endlessly.

Fstests case generic/172 with mount option "-o compress=lzo" have revealed
this bug in my test machine. Here if we have tickets to handle, we must
handle them first.

Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-01 17:23:24 +02:00
Liu Bo
a9b1fc851d Btrfs: fix endless loop in balancing block groups
Qgroup function may overwrite the saved error 'err' with 0
in case quota is not enabled, and this ends up with a
endless loop in balance because we keep going back to balance
the same block group.

It really should use 'ret' instead.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-01 17:16:47 +02:00
Josef Bacik
3dc09ec895 Btrfs: kill invalid ASSERT() in process_all_refs()
Suppose you have the following tree in snap1 on a file system mounted with -o
inode_cache so that inode numbers are recycled

└── [    258]  a
    └── [    257]  b

and then you remove b, rename a to c, and then re-create b in c so you have the
following tree

└── [    258]  c
    └── [    257]  b

and then you try to do an incremental send you will hit

ASSERT(pending_move == 0);

in process_all_refs().  This is because we assume that any recycling of inodes
will not have a pending change in our path, which isn't the case.  This is the
case for the DELETE side, since we want to remove the old file using the old
path, but on the create side we could have a pending move and need to do the
normal pending rename dance.  So remove this ASSERT() and put a comment about
why we ignore pending_move.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-09-01 17:16:47 +02:00
Miklos Szeredi
7cb35119d0 ovl: listxattr: use strnlen()
Be defensive about what underlying fs provides us in the returned xattr
list buffer.  If it's not properly null terminated, bail out with a warning
insead of BUG.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
2016-09-01 11:12:00 +02:00
Andreas Gruenbacher
0eb45fc3bb ovl: Switch to generic_getxattr
Now that overlayfs has xattr handlers for iop->{set,remove}xattr, use
those same handlers for iop->getxattr as well.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:12:00 +02:00
Miklos Szeredi
ce31513a91 ovl: copyattr after setting POSIX ACL
Setting POSIX acl may also modify the file mode, so need to copy that up to
the overlay inode.

Reported-by: Eryu Guan <eguan@redhat.com>
Fixes: d837a49bd5 ("ovl: fix POSIX ACL setting")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:12:00 +02:00
Andreas Gruenbacher
0e585ccc13 ovl: Switch to generic_removexattr
Commit d837a49bd5 ("ovl: fix POSIX ACL setting") switches from
iop->setxattr from ovl_setxattr to generic_setxattr, so switch from
ovl_removexattr to generic_removexattr as well.  As far as permission
checking goes, the same rules should apply in either case.

While doing that, rename ovl_setxattr to ovl_xattr_set to indicate that
this is not an iop->setxattr implementation and remove the unused inode
argument.

Move ovl_other_xattr_set above ovl_own_xattr_set so that they match the
order of handlers in ovl_xattr_handlers.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Fixes: d837a49bd5 ("ovl: fix POSIX ACL setting")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:12:00 +02:00
Andreas Gruenbacher
0c97be22f9 ovl: Get rid of ovl_xattr_noacl_handlers array
Use an ordinary #ifdef to conditionally include the POSIX ACL handlers
in ovl_xattr_handlers, like the other filesystems do.  Flag the code
that is now only used conditionally with __maybe_unused.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Andreas Gruenbacher
fe2b759523 ovl: Fix OVL_XATTR_PREFIX
Make sure ovl_own_xattr_handler only matches attribute names starting
with "overlay.", not "overlayXXX".

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Fixes: d837a49bd5 ("ovl: fix POSIX ACL setting")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Colin Ian King
fd36570a88 ovl: fix spelling mistake: "directries" -> "directories"
Trivial fix to spelling mistake in pr_err message.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Miklos Szeredi
2a3a2a3f35 ovl: don't cache acl on overlay layer
Some operations (setxattr/chmod) can make the cached acl stale.  We either
need to clear overlay's acl cache for the affected inode or prevent acl
caching on the overlay altogether.  Preventing caching has the following
advantages:

 - no double caching, less memory used

 - overlay cache doesn't go stale when fs clears it's own cache

Possible disadvantage is performance loss.  If that becomes a problem
get_acl() can be optimized for overlayfs.

This patch disables caching by pre setting i_*acl to a value that

  - has bit 0 set, so is_uncached_acl() will return true

  - is not equal to ACL_NOT_CACHED, so get_acl() will not overwrite it

The constant -3 was chosen for this purpose.

Fixes: 39a25b2b37 ("ovl: define ->get_acl() for overlay inodes")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Miklos Szeredi
5201dc449e ovl: use cached acl on underlying layer
Instead of calling ->get_acl() directly, use get_acl() to get the cached
value.

We will have the acl cached on the underlying inode anyway, because we do
permission checking on the both the overlay and the underlying fs.

So, since we already have double caching, this improves performance without
any cost.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Miklos Szeredi
eea2fb4851 ovl: proper cleanup of workdir
When mounting overlayfs it needs a clean "work" directory under the
supplied workdir.

Previously the mount code removed this directory if it already existed and
created a new one.  If the removal failed (e.g. directory was not empty)
then it fell back to a read-only mount not using the workdir.

While this has never been reported, it is possible to get a non-empty
"work" dir from a previous mount of overlayfs in case of crash in the
middle of an operation using the work directory.

In this case the left over state should be discarded and the overlay
filesystem will be consistent, guaranteed by the atomicity of operations on
moving to/from the workdir to the upper layer.

This patch implements cleaning out any files left in workdir.  It is
implemented using real recursion for simplicity, but the depth is limited
to 2, because the worst case is that of a directory containing whiteouts
under "work".

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
2016-09-01 11:11:59 +02:00
Miklos Szeredi
c11b9fdd6a ovl: remove posix_acl_default from workdir
Clear out posix acl xattrs on workdir and also reset the mode after
creation so that an inherited sgid bit is cleared.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: <stable@vger.kernel.org>
2016-09-01 11:11:59 +02:00
Miklos Szeredi
38b256973e ovl: handle umask and posix_acl_default correctly on creation
Setting MS_POSIXACL in sb->s_flags has the side effect of passing mode to
create functions without masking against umask.

Another problem when creating over a whiteout is that the default posix acl
is not inherited from the parent dir (because the real parent dir at the
time of creation is the work directory).

Fix these problems by:

 a) If upper fs does not have MS_POSIXACL, then mask mode with umask.

 b) If creating over a whiteout, call posix_acl_create() to get the
 inherited acls.  After creation (but before moving to the final
 destination) set these acls on the created file.  posix_acl_create() also
 updates the file creation mode as appropriate.

Fixes: 39a25b2b37 ("ovl: define ->get_acl() for overlay inodes")
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-09-01 11:11:59 +02:00
Mateusz Guzik
cd81a9170e mm: introduce get_task_exe_file
For more convenient access if one has a pointer to the task.

As a minor nit take advantage of the fact that only task lock + rcu are
needed to safely grab ->exe_file. This saves mm refcount dance.

Use the helper in proc_exe_link.

Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Richard Guy Briggs <rgb@redhat.com>
Cc: <stable@vger.kernel.org> # 4.3.x
Signed-off-by: Paul Moore <paul@paul-moore.com>
2016-08-31 16:11:20 -04:00
Linus Torvalds
9f834ec18d binfmt_elf: switch to new creds when switching to new mm
We used to delay switching to the new credentials until after we had
mapped the executable (and possible elf interpreter).  That was kind of
odd to begin with, since the new executable will actually then _run_
with the new creds, but whatever.

The bigger problem was that we also want to make sure that we turn off
prof events and tracing before we start mapping the new executable
state.  So while this is a cleanup, it's also a fix for a possible
information leak.

Reported-by: Robert Święcki <robert@swiecki.net>
Tested-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-31 09:13:56 -07:00
Konstantin Khlebnikov
17d0774f80 sysfs: correctly handle read offset on PREALLOC attrs
Attributes declared with __ATTR_PREALLOC use sysfs_kf_read() which returns
zero bytes for non-zero offset. This breaks script checkarray in mdadm tool
in debian where /bin/sh is 'dash' because its builtin 'read' reads only one
byte at a time. Script gets 'i' instead of 'idle' when reads current action
from /sys/block/$dev/md/sync_action and as a result does nothing.

This patch adds trivial implementation of partial read: generate whole
string and move required part into buffer head.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Fixes: 4ef67a8c95 ("sysfs/kernfs: make read requests on pre-alloc files use the buffer.")
Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=787950
Cc: Stable <stable@vger.kernel.org> # v3.19+
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 15:14:44 +02:00
Tejun Heo
df6a58c5c5 kernfs: don't depend on d_find_any_alias() when generating notifications
kernfs_notify_workfn() sends out file modified events for the
scheduled kernfs_nodes.  Because the modifications aren't from
userland, it doesn't have the matching file struct at hand and can't
use fsnotify_modify().  Instead, it looked up the inode and then used
d_find_any_alias() to find the dentry and used fsnotify_parent() and
fsnotify() directly to generate notifications.

The assumption was that the relevant dentries would have been pinned
if there are listeners, which isn't true as inotify doesn't pin
dentries at all and watching the parent doesn't pin the child dentries
even for dnotify.  This led to, for example, inotify watchers not
getting notifications if the system is under memory pressure and the
matching dentries got reclaimed.  It can also be triggered through
/proc/sys/vm/drop_caches or a remount attempt which involves shrinking
dcache.

fsnotify_parent() only uses the dentry to access the parent inode,
which kernfs can do easily.  Update kernfs_notify_workfn() so that it
uses fsnotify() directly for both the parent and target inodes without
going through d_find_any_alias().  While at it, supply the target file
name to fsnotify() from kernfs_node->name.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Evgeny Vereshchagin <evvers@ya.ru>
Fixes: d911d98748 ("kernfs: make kernfs_notify() trigger inotify events too")
Cc: John McCutchan <john@johnmccutchan.com>
Cc: Robert Love <rlove@rlove.org>
Cc: Eric Paris <eparis@parisplace.org>
Cc: stable@vger.kernel.org # v3.16+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31 14:48:52 +02:00
Linus Torvalds
0cf21c6609 NFS client bugfixes for 4.8
Highlights include:
 
 Stable patches:
 - Fix a refcount leak in nfs_callback_up_net
 - Fix an Oopsable condition when the flexfile pNFS driver connection to
   the DS fails
 - Fix an Oopsable condition in NFSv4.1 server callback races
 - Ensure pNFS clients stop doing I/O to the DS if their lease has expired,
   as required by the NFSv4.1 protocol
 
 Bugfixes:
 - Fix potential looping in the NFSv4.x migration code
 - Patch series to close callback races for OPEN, LAYOUTGET and LAYOUTRETURN
 - Silence WARN_ON when NFSv4.1 over RDMA is in use
 - Fix a LAYOUTCOMMIT race in the pNFS/blocks client
 - Fix pNFS timeout issues when the DS fails
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Merge tag 'nfs-for-4.8-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

  Stable patches:
   - Fix a refcount leak in nfs_callback_up_net
   - Fix an Oopsable condition when the flexfile pNFS driver connection
     to the DS fails
   - Fix an Oopsable condition in NFSv4.1 server callback races
   - Ensure pNFS clients stop doing I/O to the DS if their lease has
     expired, as required by the NFSv4.1 protocol

  Bugfixes:
   - Fix potential looping in the NFSv4.x migration code
   - Patch series to close callback races for OPEN, LAYOUTGET and
     LAYOUTRETURN
   - Silence WARN_ON when NFSv4.1 over RDMA is in use
   - Fix a LAYOUTCOMMIT race in the pNFS/blocks client
   - Fix pNFS timeout issues when the DS fails"

* tag 'nfs-for-4.8-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFSv4.x: Fix a refcount leak in nfs_callback_up_net
  NFS4: Avoid migration loops
  pNFS/flexfiles: Fix an Oopsable condition when connection to the DS fails
  NFSv4.1: Remove obsolete and incorrrect assignment in nfs4_callback_sequence
  NFSv4.1: Close callback races for OPEN, LAYOUTGET and LAYOUTRETURN
  NFSv4.1: Defer bumping the slot sequence number until we free the slot
  NFSv4.1: Delay callback processing when there are referring triples
  NFSv4.1: Fix Oopsable condition in server callback races
  SUNRPC: Silence WARN_ON when NFSv4.1 over RDMA is in use
  pnfs/blocklayout: update last_write_offset atomically with extents
  pNFS: The client must not do I/O to the DS if it's lease has expired
  pNFS: Handle NFS4ERR_OLD_STATEID correctly in LAYOUTSTAT calls
  pNFS/flexfiles: Set reasonable default retrans values for the data channel
  NFS: Allow the mount option retrans=0
  pNFS/flexfiles: Fix layoutstat periodic reporting
2016-08-30 11:14:02 -07:00
Trond Myklebust
98b0f80c23 NFSv4.x: Fix a refcount leak in nfs_callback_up_net
On error, the callers expect us to return without bumping
nn->cb_users[].

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org # v3.7+
2016-08-30 09:26:57 -04:00
Benjamin Coddington
52442f9b11 NFS4: Avoid migration loops
If a server returns itself as a location while migrating, the client may
end up getting stuck attempting to migrate twice to the same server.  Catch
this by checking if the nfs_client found is the same as the existing
client.  For the other two callers to nfs4_set_client, the nfs_client will
always be ERR_PTR(-EINVAL).

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-08-30 09:26:32 -04:00
Darrick J. Wong
ea78d80866 xfs: track log done items directly in the deferred pending work item
Christoph reports slab corruption when a deferred refcount update
aborts during _defer_finish().  The cause of this was broken log item
state tracking in xfs_defer_pending -- upon an abort,
_defer_trans_abort() will call abort_intent on all intent items,
including the ones that have already had a done item attached.

This is incorrect because each intent item has 2 refcount: the first
is released when the intent item is committed to the log; and the
second is released when the _done_ item is committed to the log, or
by the intent creator if there is no done item.  In other words, once
we log the done item, responsibility for releasing the intent item's
second refcount is transferred to the done item and /must not/ be
performed by anything else.

The dfp_committed flag should have been tracking whether or not we had
a done item so that _defer_trans_abort could decide if it needs to
abort the intent item, but due to a thinko this was not the case.  Rip
it out and track the done item directly so that we do the right thing
w.r.t. intent item freeing.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reported-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-08-30 13:51:39 +10:00
Linus Torvalds
b8927721ae Fix bugs that could cause kernel deadlocks or file system corruption
while moving xattrs to expand the extended inode.  Also add some
 sanity checks to the block group descriptors to make sure we don't end
 up overwriting the superblock.
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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:
 "Fix bugs that could cause kernel deadlocks or file system corruption
  while moving xattrs to expand the extended inode.

  Also add some sanity checks to the block group descriptors to make
  sure we don't end up overwriting the superblock"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: avoid deadlock when expanding inode size
  ext4: properly align shifted xattrs when expanding inodes
  ext4: fix xattr shifting when expanding inodes part 2
  ext4: fix xattr shifting when expanding inodes
  ext4: validate that metadata blocks do not overlap superblock
  ext4: reserve xattr index for the Hurd
2016-08-29 12:37:11 -07:00
Trond Myklebust
3dc147359e pNFS/flexfiles: Fix an Oopsable condition when connection to the DS fails
If the attempt to connect to a DS fails inside ff_layout_pg_init_read or
ff_layout_pg_init_write, then we currently end up clearing the layout
segment carried by the struct nfs_pageio_descriptor, causing an Oops
when we later call into ff_layout_read_pagelist/ff_layout_write_pagelist.

The fix is to ensure we return the layout and then retry.

Fixes: 446ca21953 ("pNFS/flexfiles: When initing reads or writes, we...")
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-08-29 15:21:16 -04:00
Christoph Hellwig
17de0a9ff3 iomap: don't set FIEMAP_EXTENT_MERGED for extent based filesystems
Filesystems like XFS that use extents should not set the
FIEMAP_EXTENT_MERGED flag in the fiemap extent structures.  To allow
for both behaviors for the upcoming gfs2 usage split the iomap
type field into type and flags, and only set FIEMAP_EXTENT_MERGED if
the IOMAP_F_MERGED flag is set.  The flags field will also come in
handy for future features such as shared extents on reflink-enabled
file systems.

Reported-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-08-29 11:33:58 +10:00
Trond Myklebust
d138027a82 NFSv4.1: Remove obsolete and incorrrect assignment in nfs4_callback_sequence
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-08-28 14:23:27 -04:00
Trond Myklebust
2e80dbe7ac NFSv4.1: Close callback races for OPEN, LAYOUTGET and LAYOUTRETURN
Defer freeing the slot until after we have processed the results from
OPEN and LAYOUTGET. This means that the server can rely on the
mechanism in RFC5661 Section 2.10.6.3 to ensure that replies to an
OPEN or LAYOUTGET/RETURN RPC call don't race with the callbacks that
apply to them.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-08-28 14:23:27 -04:00
Trond Myklebust
07e8dcbda7 NFSv4.1: Defer bumping the slot sequence number until we free the slot
For operations like OPEN or LAYOUTGET, which return recallable state
(i.e. delegations and layouts) we want to enable the mechanism for
resolving recall races in RFC5661 Section 2.10.6.3.
To do so, we will want to defer bumping the slot's sequence number until
we have finished processing the RPC results.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-08-28 14:23:26 -04:00
Trond Myklebust
045d2a6d07 NFSv4.1: Delay callback processing when there are referring triples
If CB_SEQUENCE tells us that the processing of this request depends on
the completion of one or more referring triples (see RFC 5661 Section
2.10.6.3), delay the callback processing until after the RPC requests
being referred to have completed.
If we end up delaying for more than 1/2 second, then fall back to
returning NFS4ERR_DELAY in reply to the callback.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-08-28 14:23:26 -04:00
Trond Myklebust
e09c978aae NFSv4.1: Fix Oopsable condition in server callback races
The slot table hasn't been an array since v3.7. Ensure that we
use nfs4_lookup_slot() to access the slot correctly.

Fixes: 87dda67e73 ("NFSv4.1: Allow SEQUENCE to resize the slot table...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org # v3.8+
2016-08-28 14:23:22 -04:00
Linus Torvalds
5e608a0270 Merge branch 'akpm' (patches from Andrew)
Merge fixes from Andrew Morton:
 "11 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm: silently skip readahead for DAX inodes
  dax: fix device-dax region base
  fs/seq_file: fix out-of-bounds read
  mm: memcontrol: avoid unused function warning
  mm: clarify COMPACTION Kconfig text
  treewide: replace config_enabled() with IS_ENABLED() (2nd round)
  printk: fix parsing of "brl=" option
  soft_dirty: fix soft_dirty during THP split
  sysctl: handle error writing UINT_MAX to u32 fields
  get_maintainer: quiet noisy implicit -f vcs_file_exists checking
  byteswap: don't use __builtin_bswap*() with sparse
2016-08-26 23:12:12 -07:00
Linus Torvalds
28687b935e Merge branch 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "We've queued up a few different fixes in here.  These range from
  enospc corners to fsync and quota fixes, and a few targeted at error
  handling for corrupt metadata/fuzzing"

* 'for-linus-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix lockdep warning on deadlock against an inode's log mutex
  Btrfs: detect corruption when non-root leaf has zero item
  Btrfs: check btree node's nritems
  btrfs: don't create or leak aliased root while cleaning up orphans
  Btrfs: fix em leak in find_first_block_group
  btrfs: do not background blkdev_put()
  Btrfs: clarify do_chunk_alloc()'s return value
  btrfs: fix fsfreeze hang caused by delayed iputs deal
  btrfs: update btrfs_space_info's bytes_may_use timely
  btrfs: divide btrfs_update_reserved_bytes() into two functions
  btrfs: use correct offset for reloc_inode in prealloc_file_extent_cluster()
  btrfs: qgroup: Fix qgroup incorrectness caused by log replay
  btrfs: relocation: Fix leaking qgroups numbers on data extents
  btrfs: qgroup: Refactor btrfs_qgroup_insert_dirty_extent()
  btrfs: waiting on qgroup rescan should not always be interruptible
  btrfs: properly track when rescan worker is running
  btrfs: flush_space: treat return value of do_chunk_alloc properly
  Btrfs: add ASSERT for block group's memory leak
  btrfs: backref: Fix soft lockup in __merge_refs function
  Btrfs: fix memory leak of reloc_root
2016-08-26 20:22:01 -07:00
Linus Torvalds
370f601729 dlm fixes for 4.8
This fixes a bug introduced by recent debugfs cleanup.
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Merge tag 'dlm-4.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm

Pull dlm fix from David Teigland:
 "This fixes a bug introduced by recent debugfs cleanup"

* tag 'dlm-4.8-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
  dlm: fix malfunction of dlm_tool caused by debugfs changes
2016-08-26 20:18:49 -07:00
Linus Torvalds
fd1ae51452 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "Here's a set of block fixes for the current 4.8-rc release.  This
  contains:

   - a fix for a secure erase regression, from Adrian.

   - a fix for an mmc use-after-free bug regression, also from Adrian.

   - potential zero pointer deference in bdev freezing, from Andrey.

   - a race fix for blk_set_queue_dying() from Bart.

   - a set of xen blkfront fixes from Bob Liu.

   - three small fixes for bcache, from Eric and Kent.

   - a fix for a potential invalid NVMe state transition, from Gabriel.

   - blk-mq CPU offline fix, preventing us from issuing and completing a
     request on the wrong queue.  From me.

   - revert two previous floppy changes, since they caused a user
     visibile regression.  A better fix is in the works.

   - ensure that we don't send down bios that have more than 256
     elements in them.  Fixes a crash with bcache, for example.  From
     Ming.

   - a fix for deferencing an error pointer with cgroup writeback.
     Fixes a regression.  From Vegard"

* 'for-linus' of git://git.kernel.dk/linux-block:
  mmc: fix use-after-free of struct request
  Revert "floppy: refactor open() flags handling"
  Revert "floppy: fix open(O_ACCMODE) for ioctl-only open"
  fs/block_dev: fix potential NULL ptr deref in freeze_bdev()
  blk-mq: improve warning for running a queue on the wrong CPU
  blk-mq: don't overwrite rq->mq_ctx
  block: make sure a big bio is split into at most 256 bvecs
  nvme: Fix nvme_get/set_features() with a NULL result pointer
  bdev: fix NULL pointer dereference
  xen-blkfront: free resources if xlvbd_alloc_gendisk fails
  xen-blkfront: introduce blkif_set_queue_limits()
  xen-blkfront: fix places not updated after introducing 64KB page granularity
  bcache: pr_err: more meaningful error message when nr_stripes is invalid
  bcache: RESERVE_PRIO is too small by one when prio_buckets() is a power of two.
  bcache: register_bcache(): call blkdev_put() when cache_alloc() fails
  block: Fix race triggered by blk_set_queue_dying()
  block: Fix secure erase
  nvme: Prevent controller state invalid transition
2016-08-26 18:50:07 -07:00
Vegard Nossum
088bf2ff5d fs/seq_file: fix out-of-bounds read
seq_read() is a nasty piece of work, not to mention buggy.

It has (I think) an old bug which allows unprivileged userspace to read
beyond the end of m->buf.

I was getting these:

    BUG: KASAN: slab-out-of-bounds in seq_read+0xcd2/0x1480 at addr ffff880116889880
    Read of size 2713 by task trinity-c2/1329
    CPU: 2 PID: 1329 Comm: trinity-c2 Not tainted 4.8.0-rc1+ #96
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014
    Call Trace:
      kasan_object_err+0x1c/0x80
      kasan_report_error+0x2cb/0x7e0
      kasan_report+0x4e/0x80
      check_memory_region+0x13e/0x1a0
      kasan_check_read+0x11/0x20
      seq_read+0xcd2/0x1480
      proc_reg_read+0x10b/0x260
      do_loop_readv_writev.part.5+0x140/0x2c0
      do_readv_writev+0x589/0x860
      vfs_readv+0x7b/0xd0
      do_readv+0xd8/0x2c0
      SyS_readv+0xb/0x10
      do_syscall_64+0x1b3/0x4b0
      entry_SYSCALL64_slow_path+0x25/0x25
    Object at ffff880116889100, in cache kmalloc-4096 size: 4096
    Allocated:
    PID = 1329
      save_stack_trace+0x26/0x80
      save_stack+0x46/0xd0
      kasan_kmalloc+0xad/0xe0
      __kmalloc+0x1aa/0x4a0
      seq_buf_alloc+0x35/0x40
      seq_read+0x7d8/0x1480
      proc_reg_read+0x10b/0x260
      do_loop_readv_writev.part.5+0x140/0x2c0
      do_readv_writev+0x589/0x860
      vfs_readv+0x7b/0xd0
      do_readv+0xd8/0x2c0
      SyS_readv+0xb/0x10
      do_syscall_64+0x1b3/0x4b0
      return_from_SYSCALL_64+0x0/0x6a
    Freed:
    PID = 0
    (stack is not available)
    Memory state around the buggy address:
     ffff88011688a000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
     ffff88011688a080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    >ffff88011688a100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
		       ^
     ffff88011688a180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
     ffff88011688a200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
    ==================================================================
    Disabling lock debugging due to kernel taint

This seems to be the same thing that Dave Jones was seeing here:

  https://lkml.org/lkml/2016/8/12/334

There are multiple issues here:

  1) If we enter the function with a non-empty buffer, there is an attempt
     to flush it. But it was not clearing m->from after doing so, which
     means that if we try to do this flush twice in a row without any call
     to traverse() in between, we are going to be reading from the wrong
     place -- the splat above, fixed by this patch.

  2) If there's a short write to userspace because of page faults, the
     buffer may already contain multiple lines (i.e. pos has advanced by
     more than 1), but we don't save the progress that was made so the
     next call will output what we've already returned previously. Since
     that is a much less serious issue (and I have a headache after
     staring at seq_read() for the past 8 hours), I'll leave that for now.

Link: http://lkml.kernel.org/r/1471447270-32093-1-git-send-email-vegard.nossum@oracle.com
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-08-26 17:39:35 -07:00