Commit graph

49,973 commits

Author SHA1 Message Date
Eric Sandeen
83d5f01858 xfs: cancel failed transaction in xfs_fs_commit_blocks()
If xfs_trans_reserve fails we don't cancel the transaction,
and we'll leak the allocated transaction pointer.

Spotted by Coverity.

Signed-off-by: Eric Sandeen <ssandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-24 10:15:18 +11:00
Wang Sheng-Hui
dd5e71274a xfs: remove old and redundant comment in xfs_mount_validate_sb
The error messages document the reason for the checks better than the comment
and the comments about volume mounts date back to Irix and so aren't relevant
any more. So just remove the old and redundant comment.

Signed-off-by: Wang Sheng-Hui <shhuiw@foxmail.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-24 10:15:04 +11:00
Eric Sandeen
fdadf2676a xfs: clarify async write failure ratelimit message
Today, when the "failing async writes" get ratelimited, we see:

XFS:: 62836 callbacks suppressed

Aside from the extra ":" it's not entirely clear which message is being
suppressed, especially if other messages or ratelimits are happening
at the same time.  Clarify this as i.e.:

XFS (dm-11): Failing async write on buffer block 0x140090. Retrying async write.
XFS: Failing async write: 62836 callbacks suppressed

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-24 10:14:04 +11:00
Eric Sandeen
3b9ce795fa xfs: log unmount events on console
There are times, when doing triage and forensics,
that we would like to know whether a filesystem was unmounted,
or if the plug was pulled without a clean unmount.  Log
unmounts at the same level (NOTICE) as we log mounts.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-24 10:13:37 +11:00
Eric Sandeen
fc921566f4 xfs: Ensure we have target_ip for RENAME_EXCHANGE
We shouldn't get here with RENAME_EXCHANGE set and no
target_ip, but let's be defensive, because xfs_cross_rename()
will dereference it.

Spotted by Coverity.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-24 10:12:55 +11:00
Eric Sandeen
5fb5aeeeb6 xfs: pass mp to XFS_WANT_CORRUPTED_RETURN
Today, if we hit an XFS_WANT_CORRUPTED_RETURN we don't print any
information about which filesystem hit it.  Passing in the mp allows
us to print the filesystem (device) name, which is a pretty critical
piece of information.

Tested by running fsfuzzer 'til I hit some.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 22:39:13 +11:00
Eric Sandeen
c29aad4115 xfs: pass mp to XFS_WANT_CORRUPTED_GOTO
Today, if we hit an XFS_WANT_CORRUPTED_GOTO we don't print any
information about which filesystem hit it.  Passing in the mp allows
us to print the filesystem (device) name, which is a pretty critical
piece of information.

Tested by running fsfuzzer 'til I hit some.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 22:39:08 +11:00
Dave Chinner
58c904734c xfs: inodes are new until the dentry cache is set up
Al Viro noticed a generic set of issues to do with filehandle lookup
racing with dentry cache setup. They involve a filehandle lookup
occurring while an inode is being created and the filehandle lookup
racing with the dentry creation for the real file. This can lead to
multiple dentries for the one path being instantiated. There are a
host of other issues around this same set of paths.

The underlying cause is that file handle lookup only waits on inode
cache instantiation rather than full dentry cache instantiation. XFS
is mostly immune to the problems discovered due to it's own internal
inode cache, but there are a couple of corner cases where races can
happen.

We currently clear the XFS_INEW flag when the inode is fully set up
after insertion into the cache. Newly allocated inodes are inserted
locked and so aren't usable until the allocation transaction
commits. This, however, occurs before the dentry and security
information is fully initialised and hence the inode is unlocked and
available for lookups to find too early.

To solve the problem, only clear the XFS_INEW flag for newly created
inodes once the dentry is fully instantiated. This means lookups
will retry until the XFS_INEW flag is removed from the inode and
hence avoids the race conditions in questions.

THis also means that xfs_create(), xfs_create_tmpfile() and
xfs_symlink() need to finish the setup of the inode in their error
paths if we had allocated the inode but failed later in the creation
process. xfs_symlink(), in particular, needed a lot of help to make
it's error handling match that of xfs_create().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 22:38:08 +11:00
Dave Chinner
5885ebda87 xfs: ensure truncate forces zeroed blocks to disk
A new fsync vs power fail test in xfstests indicated that XFS can
have unreliable data consistency when doing extending truncates that
require block zeroing. The blocks beyond EOF get zeroed in memory,
but we never force those changes to disk before we run the
transaction that extends the file size and exposes those blocks to
userspace. This can result in the blocks not being correctly zeroed
after a crash.

Because in-memory behaviour is correct, tools like fsx don't pick up
any coherency problems - it's not until the filesystem is shutdown
or the system crashes after writing the truncate transaction to the
journal but before the zeroed data in the page cache is flushed that
the issue is exposed.

Fix this by also flushing the dirty data in memory region between
the old size and new size when we've found blocks that need zeroing
in the truncate process.

Reported-by: Liu Bo <bo.li.liu@oracle.com>
cc: <stable@vger.kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 22:37:08 +11:00
Jan Kara
dfcc70a8c8 xfs: Fix quota type in quota structures when reusing quota file
For filesystems without separate project quota inode field in the
superblock we just reuse project quota file for group quotas (and vice
versa) if project quota file is allocated and we need group quota file.
When we reuse the file, quota structures on disk suddenly have wrong
type stored in d_flags though. Nobody really cares about this (although
structure type reported to userspace was wrong as well) except
that after commit 14bf61ffe6 (quota: Switch ->get_dqblk() and
->set_dqblk() to use bytes as space units) assertion in
xfs_qm_scall_getquota() started to trigger on xfs/106 test (apparently I
was testing without XFS_DEBUG so I didn't notice when submitting the
above commit).

Fix the problem by properly resetting ddq->d_flags when running quotacheck
for a quota file.

CC: stable@vger.kernel.org
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 22:34:17 +11:00
Dave Chinner
723cac4847 xfs: lock out page faults from extent swap operations
Extent swap operations are another extent manipulation operation
that we need to ensure does not race against mmap page faults. The
current code returns if the file is mapped prior to the swap being
done, but it could potentially race against new page faults while
the swap is in progress. Hence we should use the XFS_MMAPLOCK_EXCL
for this operation, too.

While there, fix the error path handling that can result in double
unlocks of the inodes when cancelling the swapext transaction.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:47:29 +11:00
Dave Chinner
0f9160b444 xfs: xfs_setattr_size no longer races with page faults
Now that truncate locks out new page faults, we no longer need to do
special writeback hacks in truncate to work around potential races
between page faults, page cache truncation and file size updates to
ensure we get write page faults for extending truncates on sub-page
block size filesystems. Hence we can remove the code in
xfs_setattr_size() that handles this and update the comments around
the code tha thandles page cache truncate and size updates to
reflect the new reality.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:46:58 +11:00
Dave Chinner
e8e9ad42c1 xfs: take i_mmap_lock on extent manipulation operations
Now we have the i_mmap_lock being held across the page fault IO
path, we now add extent manipulation operation exclusion by adding
the lock to the paths that directly modify extent maps. This
includes truncate, hole punching and other fallocate based
operations. The operations will now take both the i_iolock and the
i_mmaplock in exclusive mode, thereby ensuring that all IO and page
faults block without holding any page locks while the extent
manipulation is in progress.

This gives us the lock order during truncate of i_iolock ->
i_mmaplock -> page_lock -> i_lock, hence providing the same
lock order as the iolock provides the normal IO path without
involving the mmap_sem.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:45:32 +11:00
Dave Chinner
075a924d45 xfs: use i_mmaplock on write faults
Take the i_mmaplock over write page faults. These come through the
->page_mkwrite callout, so we need to wrap that calls with the
i_mmaplock.

This gives us a lock order of mmap_sem -> i_mmaplock -> page_lock
-> i_lock.

Also, move the page_mkwrite wrapper to the same region of xfs_file.c
as the read fault wrappers and add a tracepoint.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:44:54 +11:00
Dave Chinner
de0e8c20ba xfs: use i_mmaplock on read faults
Take the i_mmaplock over read page faults. These come through the
->fault callout, so we need to wrap the generic implementation
with the i_mmaplock. While there, add tracepoints for the read
fault as it passes through XFS.

This gives us a lock order of mmap_sem -> i_mmaplock -> page_lock
-> i_lock.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:44:19 +11:00
Dave Chinner
653c60b633 xfs: introduce mmap/truncate lock
Right now we cannot serialise mmap against truncate or hole punch
sanely. ->page_mkwrite is not able to take locks that the read IO
path normally takes (i.e. the inode iolock) because that could
result in lock inversions (read - iolock - page fault - page_mkwrite
- iolock) and so we cannot use an IO path lock to serialise page
write faults against truncate operations.

Instead, introduce a new lock that is used *only* in the
->page_mkwrite path that is the equivalent of the iolock. The lock
ordering in a page fault is i_mmaplock -> page lock -> i_ilock,
and so in truncate we can i_iolock -> i_mmaplock and so lock out
new write faults during the process of truncation.

Because i_mmap_lock is outside the page lock, we can hold it across
all the same operations we hold the i_iolock for. The only
difference is that we never hold the i_mmaplock in the normal IO
path and so do not ever have the possibility that we can page fault
inside it. Hence there are no recursion issues on the i_mmap_lock
and so we can use it to serialise page fault IO against inode
modification operations that affect the IO path.

This patch introduces the i_mmaplock infrastructure, lockdep
annotations and initialisation/destruction code. Use of the new lock
will be in subsequent patches.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:43:37 +11:00
Dave Chinner
964aa8d9e4 xfs: remove xfs_mod_incore_sb API
Now that there are no users of the bitfield based incore superblock
modification API, just remove the whole damn lot of it, including
all the bitfield definitions. This finally removes a lot of cruft
that has been around for a long time.

Credit goes to Christoph Hellwig for providing a great patch
connecting all the dots to enale us to do this. This patch is
derived from that work.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:24:37 +11:00
Dave Chinner
0bd5ddedcc xfs: replace xfs_mod_incore_sb_batched
Introduce helper functions for modifying fields in the superblock
into xfs_trans.c, the only caller of xfs_mod_incore_sb_batch().  We
can then use these directly in xfs_trans_unreserve_and_mod_sb() and
so remove another user of the xfs_mode_incore_sb() API without
losing any functionality or scalability of the transaction commit
code..

Based on a patch from Christoph Hellwig.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:24:11 +11:00
Dave Chinner
bab98bbe6e xfs: introduce xfs_mod_frextents
Add a new helper to modify the incore counter of free realtime
extents. This matches the helpers used for inode and data block
counters, and removes a significant users of the xfs_mod_incore_sb()
interface.

Based on a patch originally from Christoph Hellwig.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:22:54 +11:00
Dave Chinner
5681ca4006 xfs: Remove icsb infrastructure
Now that the in-core superblock infrastructure has been replaced with
generic per-cpu counters, we don't need it anymore. Nuke it from
orbit so we are sure that it won't haunt us again...

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:22:31 +11:00
Dave Chinner
0d485ada40 xfs: use generic percpu counters for free block counter
XFS has hand-rolled per-cpu counters for the superblock since before
there was any generic implementation. The free block counter is
special in that it is used for ENOSPC detection outside transaction
contexts for for delayed allocation. This means that the counter
needs to be accurate at zero. The current per-cpu counter code jumps
through lots of hoops to ensure we never run past zero, but we don't
need to make all those jumps with the generic counter
implementation.

The generic counter implementation allows us to pass a "batch"
threshold at which the addition/subtraction to the counter value
will be folded back into global value under lock. We can use this
feature to reduce the batch size as we approach 0 in a very similar
manner to the existing counters and their rebalance algorithm. If we
use a batch size of 1 as we approach 0, then every addition and
subtraction will be done against the global value and hence allow
accurate detection of zero threshold crossing.

Hence we can replace the handrolled, accurate-at-zero counters with
generic percpu counters.

Note: this removes just enough of the icsb infrastructure to compile
without warnings. The rest will go in subsequent commits.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:22:03 +11:00
Dave Chinner
e88b64ea1f xfs: use generic percpu counters for free inode counter
XFS has hand-rolled per-cpu counters for the superblock since before
there was any generic implementation. The free inode counter is not
used for any limit enforcement - the per-AG free inode counters are
used during allocation to determine if there are inode available for
allocation.

Hence we don't need any of the complexity of the hand-rolled
counters and we can simply replace them with generic per-cpu
counters similar to the inode counter.

This version introduces a xfs_mod_ifree() helper function from
Christoph Hellwig.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:19:53 +11:00
Dave Chinner
501ab32387 xfs: use generic percpu counters for inode counter
XFS has hand-rolled per-cpu counters for the superblock since before
there was any generic implementation. There are some warts around
the  use of them for the inode counter as the hand rolled counter is
designed to be accurate at zero, but has no specific accurracy at
any other value. This design causes problems for the maximum inode
count threshold enforcement, as there is no trigger that balances
the counters as they get close tothe maximum threshold.

Instead of designing new triggers for balancing, just replace the
handrolled per-cpu counter with a generic counter.  This enables us
to update the counter through the normal superblock modification
funtions, but rather than do that we add a xfs_mod_icount() helper
function (from Christoph Hellwig) and keep the percpu counter
outside the superblock in the struct xfs_mount.

This means we still need to initialise the per-cpu counter
specifically when we read the superblock, and vice versa when we
log/write it, but it does mean that we don't need to change any
other code.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:19:28 +11:00
Linus Torvalds
feaf222925 Ext4 bug fixes for 3.20. We also reserved code points for encryption
and read-only images (for which the implementation is mostly just the
 reserved code point for a read-only feature :-)
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 fixes from Ted Ts'o:
 "Ext4 bug fixes.

  We also reserved code points for encryption and read-only images (for
  which the implementation is mostly just the reserved code point for a
  read-only feature :-)"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix indirect punch hole corruption
  ext4: ignore journal checksum on remount; don't fail
  ext4: remove duplicate remount check for JOURNAL_CHECKSUM change
  ext4: fix mmap data corruption in nodelalloc mode when blocksize < pagesize
  ext4: support read-only images
  ext4: change to use setup_timer() instead of init_timer()
  ext4: reserve codepoints used by the ext4 encryption feature
  jbd2: complain about descriptor block checksum errors
2015-02-22 18:05:13 -08:00
Linus Torvalds
be5e6616dd Merge branch 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more vfs updates from Al Viro:
 "Assorted stuff from this cycle.  The big ones here are multilayer
  overlayfs from Miklos and beginning of sorting ->d_inode accesses out
  from David"

* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (51 commits)
  autofs4 copy_dev_ioctl(): keep the value of ->size we'd used for allocation
  procfs: fix race between symlink removals and traversals
  debugfs: leave freeing a symlink body until inode eviction
  Documentation/filesystems/Locking: ->get_sb() is long gone
  trylock_super(): replacement for grab_super_passive()
  fanotify: Fix up scripted S_ISDIR/S_ISREG/S_ISLNK conversions
  Cachefiles: Fix up scripted S_ISDIR/S_ISREG/S_ISLNK conversions
  VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry)
  SELinux: Use d_is_positive() rather than testing dentry->d_inode
  Smack: Use d_is_positive() rather than testing dentry->d_inode
  TOMOYO: Use d_is_dir() rather than d_inode and S_ISDIR()
  Apparmor: Use d_is_positive/negative() rather than testing dentry->d_inode
  Apparmor: mediated_filesystem() should use dentry->d_sb not inode->i_sb
  VFS: Split DCACHE_FILE_TYPE into regular and special types
  VFS: Add a fallthrough flag for marking virtual dentries
  VFS: Add a whiteout dentry type
  VFS: Introduce inode-getting helpers for layered/unioned fs environments
  Infiniband: Fix potential NULL d_inode dereference
  posix_acl: fix reference leaks in posix_acl_create
  autofs4: Wrong format for printing dentry
  ...
2015-02-22 17:42:14 -08:00
Al Viro
0a280962dc autofs4 copy_dev_ioctl(): keep the value of ->size we'd used for allocation
X-Coverup: just ask spender
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 11:43:34 -05:00
Al Viro
7e0e953bb0 procfs: fix race between symlink removals and traversals
use_pde()/unuse_pde() in ->follow_link()/->put_link() resp.

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 11:43:12 -05:00
Al Viro
0db59e5929 debugfs: leave freeing a symlink body until inode eviction
As it is, we have debugfs_remove() racing with symlink traversals.
Supply ->evict_inode() and do freeing there - inode will remain
pinned until we are done with the symlink body.

And rip the idiocy with checking if dentry is positive right after
we'd verified debugfs_positive(), which is a stronger check...

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 11:38:43 -05:00
Konstantin Khlebnikov
eb6ef3df4f trylock_super(): replacement for grab_super_passive()
I've noticed significant locking contention in memory reclaimer around
sb_lock inside grab_super_passive(). Grab_super_passive() is called from
two places: in icache/dcache shrinkers (function super_cache_scan) and
from writeback (function __writeback_inodes_wb). Both are required for
progress in memory allocator.

Grab_super_passive() acquires sb_lock to increment sb->s_count and check
sb->s_instances. It seems sb->s_umount locked for read is enough here:
super-block deactivation always runs under sb->s_umount locked for write.
Protecting super-block itself isn't a problem: in super_cache_scan() sb
is protected by shrinker_rwsem: it cannot be freed if its slab shrinkers
are still active. Inside writeback super-block comes from inode from bdi
writeback list under wb->list_lock.

This patch removes locking sb_lock and checks s_instances under s_umount:
generic_shutdown_super() unlinks it under sb->s_umount locked for write.
New variant is called trylock_super() and since it only locks semaphore,
callers must call up_read(&sb->s_umount) instead of drop_super(sb) when
they're done.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 11:38:42 -05:00
David Howells
54f2a2f427 fanotify: Fix up scripted S_ISDIR/S_ISREG/S_ISLNK conversions
Fanotify probably doesn't want to watch autodirs so make it use d_can_lookup()
rather than d_is_dir() when checking a dir watch and give an error on fake
directories.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 11:38:42 -05:00
David Howells
ce40fa78ef Cachefiles: Fix up scripted S_ISDIR/S_ISREG/S_ISLNK conversions
Fix up the following scripted S_ISDIR/S_ISREG/S_ISLNK conversions (or lack
thereof) in cachefiles:

 (1) Cachefiles mostly wants to use d_can_lookup() rather than d_is_dir() as
     it doesn't want to deal with automounts in its cache.

 (2) Coccinelle didn't find S_IS* expressions in ASSERT() statements in
     cachefiles.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 11:38:41 -05:00
David Howells
e36cb0b89c VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry)
Convert the following where appropriate:

 (1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry).

 (2) S_ISREG(dentry->d_inode) to d_is_reg(dentry).

 (3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry).  This is actually more
     complicated than it appears as some calls should be converted to
     d_can_lookup() instead.  The difference is whether the directory in
     question is a real dir with a ->lookup op or whether it's a fake dir with
     a ->d_automount op.

In some circumstances, we can subsume checks for dentry->d_inode not being
NULL into this, provided we the code isn't in a filesystem that expects
d_inode to be NULL if the dirent really *is* negative (ie. if we're going to
use d_inode() rather than d_backing_inode() to get the inode pointer).

Note that the dentry type field may be set to something other than
DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS
manages the fall-through from a negative dentry to a lower layer.  In such a
case, the dentry type of the negative union dentry is set to the same as the
type of the lower dentry.

However, if you know d_inode is not NULL at the call site, then you can use
the d_is_xxx() functions even in a filesystem.

There is one further complication: a 0,0 chardev dentry may be labelled
DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE.  Strictly, this was
intended for special directory entry types that don't have attached inodes.

The following perl+coccinelle script was used:

use strict;

my @callers;
open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') ||
    die "Can't grep for S_ISDIR and co. callers";
@callers = <$fd>;
close($fd);
unless (@callers) {
    print "No matches\n";
    exit(0);
}

my @cocci = (
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISLNK(E->d_inode->i_mode)',
    '+ d_is_symlink(E)',
    '',
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISDIR(E->d_inode->i_mode)',
    '+ d_is_dir(E)',
    '',
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISREG(E->d_inode->i_mode)',
    '+ d_is_reg(E)' );

my $coccifile = "tmp.sp.cocci";
open($fd, ">$coccifile") || die $coccifile;
print($fd "$_\n") || die $coccifile foreach (@cocci);
close($fd);

foreach my $file (@callers) {
    chomp $file;
    print "Processing ", $file, "\n";
    system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 ||
	die "spatch failed";
}

[AV: overlayfs parts skipped]

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 11:38:41 -05:00
David Howells
44bdb5e5f6 VFS: Split DCACHE_FILE_TYPE into regular and special types
Split DCACHE_FILE_TYPE into DCACHE_REGULAR_TYPE (dentries representing regular
files) and DCACHE_SPECIAL_TYPE (representing blockdev, chardev, FIFO and
socket files).

d_is_reg() and d_is_special() are added to detect these subtypes and
d_is_file() is left as the union of the two.

This allows a number of places that use S_ISREG(dentry->d_inode->i_mode) to
use d_is_reg(dentry) instead.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 11:38:38 -05:00
David Howells
df1a085af1 VFS: Add a fallthrough flag for marking virtual dentries
Add a DCACHE_FALLTHRU flag to indicate that, in a layered filesystem, this is
a virtual dentry that covers another one in a lower layer that should be used
instead.  This may be recorded on medium if directory integration is stored
there.

The flag can be set with d_set_fallthru() and tested with d_is_fallthru().

Original-author: Valerie Aurora <vaurora@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 11:38:38 -05:00
Linus Torvalds
93aaa830fc xfs: pnfs block layout support for 3.20-rc1
This update contains the implementation of the PNFS server export
 methods that enable use of XFS filesystems as a block layout target.
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Merge tag 'xfs-pnfs-for-linus-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs

Pull xfs pnfs block layout support from Dave Chinner:
 "This contains the changes to XFS needed to support the PNFS block
  layout server that you pulled in through Bruce's NFS server tree
  merge.

  I originally thought that I'd need to merge changes into the NFS
  server side, but Bruce had already picked them up and so this is
  purely changes to the fs/xfs/ codebase.

  Summary:

  This update contains the implementation of the PNFS server export
  methods that enable use of XFS filesystems as a block layout target"

* tag 'xfs-pnfs-for-linus-3.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs:
  xfs: recall pNFS layouts on conflicting access
  xfs: implement pNFS export operations
2015-02-21 14:09:38 -08:00
Linus Torvalds
24a52e412e NFS client updates for Linux 3.20
Highlights include:
 
 - Fix a use-after-free in decode_cb_sequence_args()
 - Fix a compile error when #undef CONFIG_PROC_FS
 - NFSv4.1 backchannel spinlocking issue
 - Cleanups in the NFS unstable write code requested by Linus
 - NFSv4.1 fix issues when the server denies our backchannel request
 - Cleanups in create_session and bind_conn_to_session
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Merge tag 'nfs-for-3.20-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull more NFS client updates from Trond Myklebust:
 "Highlights include:

   - Fix a use-after-free in decode_cb_sequence_args()
   - Fix a compile error when #undef CONFIG_PROC_FS
   - NFSv4.1 backchannel spinlocking issue
   - Cleanups in the NFS unstable write code requested by Linus
   - NFSv4.1 fix issues when the server denies our backchannel request
   - Cleanups in create_session and bind_conn_to_session"

* tag 'nfs-for-3.20-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  NFSv4.1: Clean up bind_conn_to_session
  NFSv4.1: Always set up a forward channel when binding the session
  NFSv4.1: Don't set up a backchannel if the server didn't agree to do so
  NFSv4.1: Clean up create_session
  pnfs: Refactor the *_layout_mark_request_commit to use pnfs_layout_mark_request_commit
  NFSv4: Kill unused nfs_inode->delegation_state field
  NFS: struct nfs_commit_info.lock must always point to inode->i_lock
  nfs: Can call nfs_clear_page_commit() instead
  nfs: Provide and use helper functions for marking a page as unstable
  SUNRPC: Always manipulate rpc_rqst::rq_bc_pa_list under xprt->bc_pa_lock
  SUNRPC: Fix a compile error when #undef CONFIG_PROC_FS
  NFSv4.1: Convert open-coded array allocation calls to kmalloc_array()
  NFSv4.1: Fix a kfree() of uninitialised pointers in decode_cb_sequence_args
2015-02-21 14:02:59 -08:00
Linus Torvalds
5fbe4c224c Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc x86 fixes from Ingo Molnar:
 "This contains:

   - EFI fixes
   - a boot printout fix
   - ASLR/kASLR fixes
   - intel microcode driver fixes
   - other misc fixes

  Most of the linecount comes from an EFI revert"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm/ASLR: Avoid PAGE_SIZE redefinition for UML subarch
  x86/microcode/intel: Handle truncated microcode images more robustly
  x86/microcode/intel: Guard against stack overflow in the loader
  x86, mm/ASLR: Fix stack randomization on 64-bit systems
  x86/mm/init: Fix incorrect page size in init_memory_mapping() printks
  x86/mm/ASLR: Propagate base load address calculation
  Documentation/x86: Fix path in zero-page.txt
  x86/apic: Fix the devicetree build in certain configs
  Revert "efi/libstub: Call get_memory_map() to obtain map and desc sizes"
  x86/efi: Avoid triple faults during EFI mixed mode calls
2015-02-21 10:41:29 -08:00
Chris Mason
e57cf21e97 Btrfs: fix allocation size calculations in alloc_btrfs_bio
Since commit 8e5cfb55d3 (Btrfs: Make raid_map array be inlined in
btrfs_bio structure), the raid map array is allocated along with the
btrfs bio in alloc_btrfs_bio.  The calculation used to decide how much
we need to allocate was using the wrong parameter passed into the
allocation function.

The passed in real_stripes will be zero if a target replace operation
is not currently running.  We want to use total_stripes instead.

Signed-off-by: Chris Mason <clm@fb.com>
Reported-by: David Sterba <dsterba@suse.cz>
Tested-by: David Sterba <dsterba@suse.cz>
2015-02-20 06:55:15 -08:00
Al Viro
ce7b9facdf Merge branch 'overlayfs-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs into for-next 2015-02-20 04:58:52 -05:00
Omar Sandoval
fed0b588be posix_acl: fix reference leaks in posix_acl_create
get_acl gets a reference which we must release in the error cases.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-20 04:56:45 -05:00
Rasmus Villemoes
76bf3f6b1d autofs4: Wrong format for printing dentry
%pD for struct file*, %pd for struct dentry*.

Fixes: a455589f18 ("assorted conversions to %p[dD]")
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-20 04:56:45 -05:00
Bastien Nocera
fcbc32bc6c coredump: Fix typo in comment
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-20 04:56:44 -05:00
Kinglong Mee
acd88d4e1a fs/aio.c: Remove duplicate function name in pr_debug messages
Have defined pr_fmt as below in fs/aio.c, so remove duplicate
function name in pr_debug message.

#define pr_fmt(fmt) "%s: " fmt, __func__

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-20 04:56:44 -05:00
David Howells
112fc894a7 configfs: Fix potential NULL d_inode dereference
Code that does this:

		if (!(d_unhashed(dentry) && dentry->d_inode)) {
			...
			simple_unlink(parent->d_inode, dentry);
		}

is broken because:

    !(d_unhashed(dentry) && dentry->d_inode)

is equivalent to:

    !d_unhashed(dentry) || !dentry->d_inode

so it is possible to get into simple_unlink() with dentry->d_inode == NULL.

simple_unlink(), however, assumes dentry->d_inode cannot be NULL.

I think that what was meant is this:

    !d_unhashed(dentry) && dentry->d_inode

and that the logical-not operator or the final close-bracket was misplaced.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-20 04:56:43 -05:00
Al Viro
db671a8ecd don't bother with most of the bad_file_ops methods
Only ->open() should be there (always failing, of course).  We never
replace ->f_op of an already opened struct file, so there's no way
for any of those methods to be called.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-20 04:03:58 -05:00
Linus Torvalds
2b9fb532d4 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "This pull is mostly cleanups and fixes:

   - The raid5/6 cleanups from Zhao Lei fixup some long standing warts
     in the code and add improvements on top of the scrubbing support
     from 3.19.

   - Josef has round one of our ENOSPC fixes coming from large btrfs
     clusters here at FB.

   - Dave Sterba continues a long series of cleanups (thanks Dave), and
     Filipe continues hammering on corner cases in fsync and others

  This all was held up a little trying to track down a use-after-free in
  btrfs raid5/6.  It's not clear yet if this is just made easier to
  trigger with this pull or if its a new bug from the raid5/6 cleanups.
  Dave Sterba is the only one to trigger it so far, but he has a
  consistent way to reproduce, so we'll get it nailed shortly"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (68 commits)
  Btrfs: don't remove extents and xattrs when logging new names
  Btrfs: fix fsync data loss after adding hard link to inode
  Btrfs: fix BUG_ON in btrfs_orphan_add() when delete unused block group
  Btrfs: account for large extents with enospc
  Btrfs: don't set and clear delalloc for O_DIRECT writes
  Btrfs: only adjust outstanding_extents when we do a short write
  btrfs: Fix out-of-space bug
  Btrfs: scrub, fix sleep in atomic context
  Btrfs: fix scheduler warning when syncing log
  Btrfs: Remove unnecessary placeholder in btrfs_err_code
  btrfs: cleanup init for list in free-space-cache
  btrfs: delete chunk allocation attemp when setting block group ro
  btrfs: clear bio reference after submit_one_bio()
  Btrfs: fix scrub race leading to use-after-free
  Btrfs: add missing cleanup on sysfs init failure
  Btrfs: fix race between transaction commit and empty block group removal
  btrfs: add more checks to btrfs_read_sys_array
  btrfs: cleanup, rename a few variables in btrfs_read_sys_array
  btrfs: add checks for sys_chunk_array sizes
  btrfs: more superblock checks, lower bounds on devices and sectorsize/nodesize
  ...
2015-02-19 14:36:00 -08:00
Linus Torvalds
4533f6e27a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull Ceph changes from Sage Weil:
 "On the RBD side, there is a conversion to blk-mq from Christoph,
  several long-standing bug fixes from Ilya, and some cleanup from
  Rickard Strandqvist.

  On the CephFS side there is a long list of fixes from Zheng, including
  improved session handling, a few IO path fixes, some dcache management
  correctness fixes, and several blocking while !TASK_RUNNING fixes.

  The core code gets a few cleanups and Chaitanya has added support for
  TCP_NODELAY (which has been used on the server side for ages but we
  somehow missed on the kernel client).

  There is also an update to MAINTAINERS to fix up some email addresses
  and reflect that Ilya and Zheng are doing most of the maintenance for
  RBD and CephFS these days.  Do not be surprised to see a pull request
  come from one of them in the future if I am unavailable for some
  reason"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (27 commits)
  MAINTAINERS: update Ceph and RBD maintainers
  libceph: kfree() in put_osd() shouldn't depend on authorizer
  libceph: fix double __remove_osd() problem
  rbd: convert to blk-mq
  ceph: return error for traceless reply race
  ceph: fix dentry leaks
  ceph: re-send requests when MDS enters reconnecting stage
  ceph: show nocephx_require_signatures and notcp_nodelay options
  libceph: tcp_nodelay support
  rbd: do not treat standalone as flatten
  ceph: fix atomic_open snapdir
  ceph: properly mark empty directory as complete
  client: include kernel version in client metadata
  ceph: provide seperate {inode,file}_operations for snapdir
  ceph: fix request time stamp encoding
  ceph: fix reading inline data when i_size > PAGE_SIZE
  ceph: avoid block operation when !TASK_RUNNING (ceph_mdsc_close_sessions)
  ceph: avoid block operation when !TASK_RUNNING (ceph_get_caps)
  ceph: avoid block operation when !TASK_RUNNING (ceph_mdsc_sync)
  rbd: fix error paths in rbd_dev_refresh()
  ...
2015-02-19 14:14:42 -08:00
Ingo Molnar
a267b0a349 Merge branch 'tip-x86-kaslr' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp into x86/urgent
Pull ASLR and kASLR fixes from Borislav Petkov:

  - Add a global flag announcing KASLR state so that relevant code can do
    informed decisions based on its setting. (Jiri Kosina)

  - Fix a stack randomization entropy decrease bug. (Hector Marco-Gisbert)

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-02-19 12:31:34 +01:00
Hector Marco-Gisbert
4e7c22d447 x86, mm/ASLR: Fix stack randomization on 64-bit systems
The issue is that the stack for processes is not properly randomized on
64 bit architectures due to an integer overflow.

The affected function is randomize_stack_top() in file
"fs/binfmt_elf.c":

  static unsigned long randomize_stack_top(unsigned long stack_top)
  {
           unsigned int random_variable = 0;

           if ((current->flags & PF_RANDOMIZE) &&
                   !(current->personality & ADDR_NO_RANDOMIZE)) {
                   random_variable = get_random_int() & STACK_RND_MASK;
                   random_variable <<= PAGE_SHIFT;
           }
           return PAGE_ALIGN(stack_top) + random_variable;
           return PAGE_ALIGN(stack_top) - random_variable;
  }

Note that, it declares the "random_variable" variable as "unsigned int".
Since the result of the shifting operation between STACK_RND_MASK (which
is 0x3fffff on x86_64, 22 bits) and PAGE_SHIFT (which is 12 on x86_64):

	  random_variable <<= PAGE_SHIFT;

then the two leftmost bits are dropped when storing the result in the
"random_variable". This variable shall be at least 34 bits long to hold
the (22+12) result.

These two dropped bits have an impact on the entropy of process stack.
Concretely, the total stack entropy is reduced by four: from 2^28 to
2^30 (One fourth of expected entropy).

This patch restores back the entropy by correcting the types involved
in the operations in the functions randomize_stack_top() and
stack_maxrandom_size().

The successful fix can be tested with:

  $ for i in `seq 1 10`; do cat /proc/self/maps | grep stack; done
  7ffeda566000-7ffeda587000 rw-p 00000000 00:00 0                          [stack]
  7fff5a332000-7fff5a353000 rw-p 00000000 00:00 0                          [stack]
  7ffcdb7a1000-7ffcdb7c2000 rw-p 00000000 00:00 0                          [stack]
  7ffd5e2c4000-7ffd5e2e5000 rw-p 00000000 00:00 0                          [stack]
  ...

Once corrected, the leading bytes should be between 7ffc and 7fff,
rather than always being 7fff.

Signed-off-by: Hector Marco-Gisbert <hecmargi@upv.es>
Signed-off-by: Ismael Ripoll <iripoll@upv.es>
[ Rebased, fixed 80 char bugs, cleaned up commit message, added test example and CVE ]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Fixes: CVE-2015-1593
Link: http://lkml.kernel.org/r/20150214173350.GA18393@www.outflux.net
Signed-off-by: Borislav Petkov <bp@suse.de>
2015-02-19 12:21:36 +01:00
Yan, Zheng
4d41cef279 ceph: return error for traceless reply race
When we receives traceless reply for request that created new inode,
we re-send a lookup request to MDS get information of the newly created
inode. (VFS expects FS' callback return an inode in create case)
This breaks one request into two requests. Other client may modify or
move to the new inode in the middle.

When the race happens, ceph_handle_notrace_create() unconditionally
links the dentry for 'create' operation to the inode returned by lookup.
This may confuse VFS when the inode is a directory (VFS does not allow
multiple linkages for directory inode).

This patch makes ceph_handle_notrace_create() when it detect a race.
This event should be rare and it happens only when we talk to old MDS.
Recent MDS does not send traceless reply for request that creates new
inode.

Signed-off-by: Yan, Zheng <zyan@redhat.com>
2015-02-19 13:31:40 +03:00