When a buffer is modified, logged and committed, it ultimately ends
up sitting on the AIL with a dirty bli waiting for metadata
writeback. If another transaction locks and invalidates the buffer
(freeing an inode chunk, for example) in the meantime, the bli is
flagged as stale, the dirty state is cleared and the bli remains in
the AIL.
If a shutdown occurs before the transaction that has invalidated the
buffer is committed, the transaction is ultimately aborted. The log
items are flagged as such and ->iop_unlock() handles the aborted
items. Because the bli is clean (due to the invalidation),
->iop_unlock() unconditionally releases it. The log item may still
reside in the AIL, however, which means the I/O completion handler
may still run and attempt to access it. This results in assert
failure due to the release of the bli while still present in the AIL
and a subsequent NULL dereference and panic in the buffer I/O
completion handling. This can be reproduced by running generic/388
in repetition.
To avoid this problem, update xfs_buf_item_unlock() to first check
whether the bli is aborted and if so, remove it from the AIL before
it is released. This ensures that the bli is no longer accessed
during the shutdown sequence after it has been freed.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
If a filesystem shutdown occurs with a buffer log item in the CIL
and a log force occurs, the ->iop_unpin() handler is generally
expected to tear down the bli properly. This entails freeing the bli
memory and releasing the associated hold on the buffer so it can be
released and the filesystem unmounted.
If this sequence occurs while ->bli_refcount is elevated (i.e.,
another transaction is open and attempting to modify the buffer),
however, ->iop_unpin() may not be responsible for releasing the bli.
Instead, the transaction may release the final ->bli_refcount
reference and thus xfs_trans_brelse() is responsible for tearing
down the bli.
While xfs_trans_brelse() does drop the reference count, it only
attempts to release the bli if it is clean (i.e., not in the
CIL/AIL). If the filesystem is shutdown and the bli is sitting dirty
in the CIL as noted above, this ends up skipping the last
opportunity to release the bli. In turn, this leaves the hold on the
buffer and causes an unmount hang. This can be reproduced by running
generic/388 in repetition.
Update xfs_trans_brelse() to handle this shutdown corner case
correctly. If the final bli reference is dropped and the filesystem
is shutdown, remove the bli from the AIL (if necessary) and release
the bli to drop the buffer hold and ensure an unmount does not hang.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
gcc-7 flags the use of integer math inside of a condition
as a potential bug:
fs/xfs/xfs_bmap_util.c: In function 'xfs_swap_extents_check_format':
fs/xfs/xfs_bmap_util.c:1619:8: error: '<<' in boolean context, did you mean '<' ? [-Werror=int-in-bool-context]
fs/xfs/xfs_bmap_util.c:1629:8: error: '<<' in boolean context, did you mean '<' ? [-Werror=int-in-bool-context]
There is already a helper function for testing the di_forkoff
field for zero, so let's use that instead to shut up the warning.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The t_lsn is not used anymore and the t_commit_lsn is used as a tmp
storage for the checkpoint sequence number only in the current code.
And the start/commit lsn are tracked as a transaction group tag in
the xfs_cil_ctx instead of a single transaction, so remove them from
the xfs_trans structure and their users to match with the design.
Signed-off-by: Shan Hai <shan.hai@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
XFS_HSIZE is an extremly confusing way to calculate the size of handle_t.
Given that handle_t always only had two sizes, and one of them isn't
even covered by XFS_HSIZE to start with just remove the macro and use
a constant sizeof expression.
Note that XFS_HSIZE isn't used in xfsprogs, xfsdump or xfstests either.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
If a transaction log reservation overrun occurs, the ticket data
associated with the reservation is dumped in xfs_log_commit_cil().
This occurs long after the transaction items and details have been
removed from the transaction and effectively lost. This limited set
of ticket data provides very little information to support debugging
transaction overruns based on the typical report.
To improve transaction log reservation overrun reporting, create a
helper to dump transaction details such as log items, log vector
data, etc., as well as the underlying ticket data for the
transaction. Move the overrun detection from xfs_log_commit_cil() to
xlog_cil_insert_items() so it occurs prior to migration of the
logged items to the CIL. Call the new helper such that it is able to
dump this transaction data before it is lost.
Also, warn on overrun to provide callstack context for the offending
transaction and include a few additional messages from
xlog_cil_insert_items() to display the reservation consumed locally
for overhead such as log vector headers, split region headers and
the context ticket. This provides a complete general breakdown of
the reservation consumption of a transaction when/if it happens to
overrun the reservation.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Transaction reservation overrun detection currently occurs too late
to print useful information about the offending transaction.
Ideally, the transaction data is printed before the associated log
items are moved from the transaction to the CIL, which occurs in
xlog_cil_insert_items(), such that details of the items logged by
the transaction are available for analysis.
Refactor xlog_cil_insert_items() to facilitate moving tx overrun
detection to this function. Update the function to track each bit of
extra log reservation stolen from the transaction (i.e., such as for
the CIL context ticket) and perform the log item migration as the
last operation before the CIL lock is released. This creates a
context where the transaction reservation consumption has been fully
calculated when the log items are moved to the CIL. This patch makes
no functional changes.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
xlog_print_tic_res() pre-dates delayed logging and the committed
items list (CIL) and thus retains some factoring warts, such as hard
coded function names in the output and the fact that it induces a
shutdown.
In preparation for more detailed logging of regular transaction
overrun situations, refactor xlog_print_tic_res() to be slightly
more generic. Reword some of the warning messages and pull the
shutdown into the callers.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
While configurable at runtime, the DEBUG mode assert failure
behavior is usually either desired or not for a particular
situation. For example, developers using kernel modules may prefer
for fatal asserts to remain disabled across module reloads while QE
engineers doing broad regression testing may prefer to have fatal
asserts enabled on boot to facilitate data collection for bug
reports.
To provide a compromise/convenience for developers, create a Kconfig
option that sets the default value of the DEBUG mode 'bug_on_assert'
sysfs tunable. The default behavior remains to trigger kernel BUGs
on assert failures to preserve existing behavior across kernel
configuration updates with DEBUG mode enabled.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
In DEBUG mode, assert failures unconditionally trigger a kernel BUG.
This is useful in diagnostic situations to panic a system and
collect detailed state information at the time of a failure.
This can also cause problems in cases where DEBUG mode code is
desired but it is preferable not trigger kernel BUGs on assert
failure. For example, during development of new code or during
certain xfstests tests that intentionally cause corruption and test
the kernel for survival (but otherwise may expect to trigger assert
failures).
To provide additional flexibility, create the
<sysfs>/fs/xfs/debug/bug_on_assert tunable to configure assert
failure behavior at runtime. This tunable is only available in DEBUG
mode and is enabled by default to preserve existing default
behavior. When disabled, assert failures in DEBUG mode result in
kernel warnings.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
In a pathological scenario where we are trying to bunmapi a single
extent in which every other block is shared, it's possible that trying
to unmap the entire large extent in a single transaction can generate so
many EFIs that we overflow the transaction reservation.
Therefore, use a heuristic to guess at the number of blocks we can
safely unmap from a reflink file's data fork in an single transaction.
This should prevent problems such as the log head slamming into the tail
and ASSERTs that trigger because we've exceeded the transaction
reservation.
Note that since bunmapi can fail to unmap the entire range, we must also
teach the deferred unmap code to roll into a new transaction whenever we
get low on reservation.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
[hch: random edits, all bugs are my fault]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Currently, the dir2 leaf block getdents function uses a complex state
tracking mechanism to create a shadow copy of the block mappings and
then uses the shadow copy to schedule readahead. Since the read and
readahead functions are perfectly capable of reading the mappings
themselves, we can tear all that out in favor of a simpler function that
simply keeps pushing the readahead window further out.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reclaim during quotacheck can lead to deadlocks on the dquot flush
lock:
- Quotacheck populates a local delwri queue with the physical dquot
buffers.
- Quotacheck performs the xfs_qm_dqusage_adjust() bulkstat and
dirties all of the dquots.
- Reclaim kicks in and attempts to flush a dquot whose buffer is
already queud on the quotacheck queue. The flush succeeds but
queueing to the reclaim delwri queue fails as the backing buffer is
already queued. The flush unlock is now deferred to I/O completion
of the buffer from the quotacheck queue.
- The dqadjust bulkstat continues and dirties the recently flushed
dquot once again.
- Quotacheck proceeds to the xfs_qm_flush_one() walk which requires
the flush lock to update the backing buffers with the in-core
recalculated values. It deadlocks on the redirtied dquot as the
flush lock was already acquired by reclaim, but the buffer resides
on the local delwri queue which isn't submitted until the end of
quotacheck.
This is reproduced by running quotacheck on a filesystem with a
couple million inodes in low memory (512MB-1GB) situations. This is
a regression as of commit 43ff2122e6 ("xfs: on-stack delayed write
buffer lists"), which removed a trylock and buffer I/O submission
from the quotacheck dquot flush sequence.
Quotacheck first resets and collects the physical dquot buffers in a
delwri queue. Then, it traverses the filesystem inodes via bulkstat,
updates the in-core dquots, flushes the corrected dquots to the
backing buffers and finally submits the delwri queue for I/O. Since
the backing buffers are queued across the entire quotacheck
operation, dquot reclaim cannot possibly complete a dquot flush
before quotacheck completes.
Therefore, quotacheck must submit the buffer for I/O in order to
cycle the flush lock and flush the dirty in-core dquot to the
buffer. Add a delwri queue buffer push mechanism to submit an
individual buffer for I/O without losing the delwri queue status and
use it from quotacheck to avoid the deadlock. This restores
quotacheck behavior to as before the regression was introduced.
Reported-by: Martin Svec <martin.svec@zoner.cz>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Stack guard page is a useful feature to reduce a risk of stack smashing
into a different mapping. We have been using a single page gap which
is sufficient to prevent having stack adjacent to a different mapping.
But this seems to be insufficient in the light of the stack usage in
userspace. E.g. glibc uses as large as 64kB alloca() in many commonly
used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX]
which is 256kB or stack strings with MAX_ARG_STRLEN.
This will become especially dangerous for suid binaries and the default
no limit for the stack size limit because those applications can be
tricked to consume a large portion of the stack and a single glibc call
could jump over the guard page. These attacks are not theoretical,
unfortunatelly.
Make those attacks less probable by increasing the stack guard gap
to 1MB (on systems with 4k pages; but make it depend on the page size
because systems with larger base pages might cap stack allocations in
the PAGE_SIZE units) which should cover larger alloca() and VLA stack
allocations. It is obviously not a full fix because the problem is
somehow inherent, but it should reduce attack space a lot.
One could argue that the gap size should be configurable from userspace,
but that can be done later when somebody finds that the new 1MB is wrong
for some special case applications. For now, add a kernel command line
option (stack_guard_gap) to specify the stack gap size (in page units).
Implementation wise, first delete all the old code for stack guard page:
because although we could get away with accounting one extra page in a
stack vma, accounting a larger gap can break userspace - case in point,
a program run with "ulimit -S -v 20000" failed when the 1MB gap was
counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK
and strict non-overcommit mode.
Instead of keeping gap inside the stack vma, maintain the stack guard
gap as a gap between vmas: using vm_start_gap() in place of vm_start
(or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few
places which need to respect the gap - mainly arch_get_unmapped_area(),
and and the vma tree's subtree_gap support for that.
Original-patch-by: Oleg Nesterov <oleg@redhat.com>
Original-patch-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Helge Deller <deller@gmx.de> # parisc
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fixups from Zheng, prompted by the ongoing y2038 work.
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Merge tag 'ceph-for-4.12-rc6' of git://github.com/ceph/ceph-client
Pull ceph fixes from Ilya Dryomov:
"A fix for an old ceph ->fh_to_* bug from Luis and two timestamp fixups
from Zheng, prompted by the ongoing y2038 work"
* tag 'ceph-for-4.12-rc6' of git://github.com/ceph/ceph-client:
ceph: unify inode i_ctime update
ceph: use current_kernel_time() to get request time stamp
ceph: check i_nlink while converting a file handle to dentry
- Fix some bogus ASSERT failures on CONFIG_SMP=n and CONFIG_XFS_DEBUG=y.
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Merge tag 'xfs-4.12-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull xfs fix from Darrick Wong:
"One more bugfix for you for 4.12-rc6 to fix something that came up in
an earlier rc:
- Fix some bogus ASSERT failures on CONFIG_SMP=n and CONFIG_XFS_DEBUG=y"
* tag 'xfs-4.12-fixes-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: fix spurious spin_is_locked() assert failures on non-smp kernels
Pull ufs fixes from Al Viro:
"Fix assorted ufs bugs: a couple of deadlocks, fs corruption in
truncate(), oopsen on tail unpacking and truncate when racing with
vmscan, mild fs corruption (free blocks stats summary buggered, *BSD
fsck would complain and fix), several instances of broken logics
around reserved blocks (starting with "check almost never triggers
when it should" and then there are issues with sufficiently large
UFS2)"
[ Note: ufs hasn't gotten any loving in a long time, because nobody
really seems to use it. These ufs fixes are triggered by people
actually caring now, not some sudden influx of new bugs. - Linus ]
* 'ufs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ufs_truncate_blocks(): fix the case when size is in the last direct block
ufs: more deadlock prevention on tail unpacking
ufs: avoid grabbing ->truncate_mutex if possible
ufs_get_locked_page(): make sure we have buffer_heads
ufs: fix s_size/s_dsize users
ufs: fix reserved blocks check
ufs: make ufs_freespace() return signed
ufs: fix logics in "ufs: make fsck -f happy"
Pull vfs fixes from Al Viro:
"A couple of fixes; a leak in mntns_install() caught by Andrei (this
cycle regression) + d_invalidate() softlockup fix - that had been
reported by a bunch of people lately, but the problem is pretty old"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: don't forget to put old mntns in mntns_install
Hang/soft lockup in d_invalidate with simultaneous calls
Anon and hugetlbfs handle FOLL_DUMP set by get_dump_page() internally to
__get_user_pages().
shmem as opposed has no special FOLL_DUMP handling there so
handle_mm_fault() is invoked without mmap_sem and ends up calling
handle_userfault() that isn't expecting to be invoked without mmap_sem
held.
This makes handle_userfault() fail immediately if invoked through
shmem_vm_ops->fault during coredumping and solves the problem.
The side effect is a BUG_ON with no lock held triggered by the
coredumping process which exits. Only 4.11 is affected, pre-4.11 anon
memory holes are skipped in __get_user_pages by checking FOLL_DUMP
explicitly against empty pagetables (mm/gup.c:no_page_table()).
It's zero cost as we already had a check for current->flags to prevent
futex to trigger userfaults during exit (PF_EXITING).
Link: http://lkml.kernel.org/r/20170615214838.27429-1-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: <stable@vger.kernel.org> [4.11+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
And while I'm sending you this I'm also sneaking in a trivial new helper
from Bart so that we don't need inter-tree dependencies for the next merge
window.
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Merge tag 'configfs-for-4.12' of git://git.infradead.org/users/hch/configfs
Pull configfs updates from Christoph Hellwig:
"A fix from Nic for a race seen in production (including a stable tag).
And while I'm sending you this I'm also sneaking in a trivial new
helper from Bart so that we don't need inter-tree dependencies for the
next merge window"
* tag 'configfs-for-4.12' of git://git.infradead.org/users/hch/configfs:
configfs: Introduce config_item_get_unless_zero()
configfs: Fix race between create_link and configfs_rmdir
Fixes: 4f757f3cbf54 ("make sure that mntns_install() doesn't end up with referral for root")
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
It's not hard to trigger a bunch of d_invalidate() on the same
dentry in parallel. They end up fighting each other - any
dentry picked for removal by one will be skipped by the rest
and we'll go for the next iteration through the entire
subtree, even if everything is being skipped. Morevoer, we
immediately go back to scanning the subtree. The only thing
we really need is to dissolve all mounts in the subtree and
as soon as we've nothing left to do, we can just unhash the
dentry and bugger off.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull crypto fix from Herbert Xu:
"This fixes a bug on sparc where we may dereference freed stack memory"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: Work around deallocated stack frame reference gcc bug on sparc.
The logics when deciding whether we need to do anything with direct blocks
is broken when new size is within the last direct block. It's better to
find the path to the last byte _not_ to be removed and use that instead
of the path to the beginning of the first block to be freed...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
tail unpacking is done in a wrong place; the deadlocks galore
is best dealt with by doing that in ->write_iter() (and switching
to iomap, while we are at it), but that's rather painful to
backport. The trouble comes from grabbing pages that cover
the beginning of tail from inside of ufs_new_fragments(); ongoing
pageout of any of those is going to deadlock on ->truncate_mutex
with process that got around to extending the tail holding that
and waiting for page to get unlocked, while ->writepage() on
that page is waiting on ->truncate_mutex.
The thing is, we don't need ->truncate_mutex when the fragment
we are trying to map is within the tail - the damn thing is
allocated (tail can't contain holes).
Let's do a plain lookup and if the fragment is present, we can
just pretend that we'd won the race in almost all cases. The
only exception is a fragment between the end of tail and the
end of block containing tail.
Protect ->i_lastfrag with ->meta_lock - read_seqlock_excl() is
sufficient.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
callers rely upon that, but find_lock_page() racing with attempt of
page eviction by memory pressure might have left us with
* try_to_free_buffers() successfully done
* __remove_mapping() failed, leaving the page in our mapping
* find_lock_page() returning an uptodate page with no
buffer_heads attached.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
For UFS2 we need 64bit variants; we even store them in uspi, but
use 32bit ones instead. One wrinkle is in handling of reserved
space - recalculating it every time had been stupid all along, but
now it would become really ugly. Just calculate it once...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
a) honour ->s_minfree; don't just go with default (5)
b) don't bother with capability checks until we know we'll need them
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Storing stats _only_ at new locations is wrong for UFS1; old
locations should always be kept updated. The check for "has
been converted to use of new locations" is also wrong - it
should be "->fs_maxbsize is equal to ->fs_bsize".
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Current __ceph_setattr() can set inode's i_ctime to current_time(),
req->r_stamp or attr->ia_ctime. These time stamps may have minor
differences. It may cause potential problem.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
ceph uses ktime_get_real_ts() to get request time stamp. In most
other cases, current_kernel_time() is used to get time stamp for
filesystem operations (called by current_time()).
There is granularity difference between ktime_get_real_ts() and
current_kernel_time(). The later one can be up to one jiffy behind
the former one. This can causes inode's ctime to go back.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Converting a file handle to a dentry can be done call after the inode
unlink. This means that __fh_to_dentry() requires an extra check to
verify the number of links is not 0.
The issue can be easily reproduced using xfstest generic/426, which does
something like:
name_to_handle_at(&fh)
echo 3 > /proc/sys/vm/drop_caches
unlink()
open_by_handle_at(&fh)
The call to open_by_handle_at() should fail, as the file doesn't exist
anymore.
Link: http://tracker.ceph.com/issues/19958
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
failures.
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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 various bug fixes in ext4 caused by races and memory allocation
failures"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix fdatasync(2) after extent manipulation operations
ext4: fix data corruption for mmap writes
ext4: fix data corruption with EXT4_GET_BLOCKS_ZERO
ext4: fix quota charging for shared xattr blocks
ext4: remove redundant check for encrypted file on dio write path
ext4: remove unused d_name argument from ext4_search_dir() et al.
ext4: fix off-by-one error when writing back pages before dio read
ext4: fix off-by-one on max nr_pages in ext4_find_unwritten_pgoff()
ext4: keep existing extra fields when inode expands
ext4: handle the rest of ext4_mb_load_buddy() ENOMEM errors
ext4: fix off-by-in in loop termination in ext4_find_unwritten_pgoff()
ext4: fix SEEK_HOLE
jbd2: preserve original nofs flag during journal restart
ext4: clear lockdep subtype for quota files on quota off
Pull UFS fixes from Al Viro:
"This is just the obvious backport fodder; I'm pretty sure that there
will be more - definitely so wrt performance and quite possibly
correctness as well"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ufs: we need to sync inode before freeing it
excessive checks in ufs_write_failed() and ufs_evict_inode()
ufs_getfrag_block(): we only grab ->truncate_mutex on block creation path
ufs_extend_tail(): fix the braino in calling conventions of ufs_new_fragments()
ufs: set correct ->s_maxsize
ufs: restore maintaining ->i_blocks
fix ufs_isblockset()
ufs: restore proper tail allocation
Pull btrfs fixes from Chris Mason:
"Some fixes that Dave Sterba collected.
We've been hitting an early enospc problem on production machines that
Omar tracked down to an old int->u64 mistake. I waited a bit on this
pull to make sure it was really the problem from production, but it's
on ~2100 hosts now and I think we're good.
Omar also noticed a commit in the queue would make new early ENOSPC
problems. I pulled that out for now, which is why the top three
commits are younger than the rest.
Otherwise these are all fixes, some explaining very old bugs that
we've been poking at for a while"
* 'for-linus-4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix delalloc accounting leak caused by u32 overflow
Btrfs: clear EXTENT_DEFRAG bits in finish_ordered_io
btrfs: tree-log.c: Wrong printk information about namelen
btrfs: fix race with relocation recovery and fs_root setup
btrfs: fix memory leak in update_space_info failure path
btrfs: use correct types for page indices in btrfs_page_exists_in_range
btrfs: fix incorrect error return ret being passed to mapping_set_error
btrfs: Make flush bios explicitely sync
btrfs: fiemap: Cache and merge fiemap extent before submit it to user
As it is, short copy in write() to append-only file will fail
to truncate the excessive allocated blocks. As the matter of
fact, all checks in ufs_truncate_blocks() are either redundant
or wrong for that caller. As for the only other caller
(ufs_evict_inode()), we only need the file type checks there.
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
... and it really needs splitting into "new" and "extend" cases, but that's for
later
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
btrfs_calc_trans_metadata_size() does an unsigned 32-bit multiplication,
which can overflow if num_items >= 4 GB / (nodesize * BTRFS_MAX_LEVEL * 2).
For a nodesize of 16kB, this overflow happens at 16k items. Usually,
num_items is a small constant passed to btrfs_start_transaction(), but
we also use btrfs_calc_trans_metadata_size() for metadata reservations
for extent items in btrfs_delalloc_{reserve,release}_metadata().
In drop_outstanding_extents(), num_items is calculated as
inode->reserved_extents - inode->outstanding_extents. The difference
between these two counters is usually small, but if many delalloc
extents are reserved and then the outstanding extents are merged in
btrfs_merge_extent_hook(), the difference can become large enough to
overflow in btrfs_calc_trans_metadata_size().
The overflow manifests itself as a leak of a multiple of 4 GB in
delalloc_block_rsv and the metadata bytes_may_use counter. This in turn
can cause early ENOSPC errors. Additionally, these WARN_ONs in
extent-tree.c will be hit when unmounting:
WARN_ON(fs_info->delalloc_block_rsv.size > 0);
WARN_ON(fs_info->delalloc_block_rsv.reserved > 0);
WARN_ON(space_info->bytes_pinned > 0 ||
space_info->bytes_reserved > 0 ||
space_info->bytes_may_use > 0);
Fix it by casting nodesize to a u64 so that
btrfs_calc_trans_metadata_size() does a full 64-bit multiplication.
While we're here, do the same in btrfs_calc_trunc_metadata_size(); this
can't overflow with any existing uses, but it's better to be safe here
than have another hard-to-debug problem later on.
Cc: stable@vger.kernel.org
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Before this, we use 'filled' mode here, ie. if all range has been
filled with EXTENT_DEFRAG bits, get to clear it, but if the defrag
range joins the adjacent delalloc range, then we'll have EXTENT_DEFRAG
bits in extent_state until releasing this inode's pages, and that
prevents extent_data from being freed.
This clears the bit if any was found within the ordered extent.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
