Extents are cached in read_extent_tree_block(); as a result, extents
are not cached for inodes with depth == 0 when we try to find the
extent using ext4_find_extent(). The result of the lookup is cached
in ext4_map_blocks() but is only a subset of the extent on disk. As a
result, the contents of extents status cache can get very badly
fragmented for certain workloads, such as a random 4k read workload.
File size of /mnt/test is 33554432 (8192 blocks of 4096 bytes)
ext: logical_offset: physical_offset: length: expected: flags:
0: 0.. 8191: 40960.. 49151: 8192: last,eof
$ perf record -e 'ext4:ext4_es_*' /root/bin/fio --name=t --direct=0 --rw=randread --bs=4k --filesize=32M --size=32M --filename=/mnt/test
$ perf script | grep ext4_es_insert_extent | head -n 10
fio 131 [000] 13.975421: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [494/1) mapped 41454 status W
fio 131 [000] 13.975939: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [6064/1) mapped 47024 status W
fio 131 [000] 13.976467: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [6907/1) mapped 47867 status W
fio 131 [000] 13.976937: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [3850/1) mapped 44810 status W
fio 131 [000] 13.977440: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [3292/1) mapped 44252 status W
fio 131 [000] 13.977931: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [6882/1) mapped 47842 status W
fio 131 [000] 13.978376: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [3117/1) mapped 44077 status W
fio 131 [000] 13.978957: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [2896/1) mapped 43856 status W
fio 131 [000] 13.979474: ext4:ext4_es_insert_extent: dev 253,0 ino 12 es [7479/1) mapped 48439 status W
Fix this by caching the extents for inodes with depth == 0 in
ext4_find_extent().
[ Renamed ext4_es_cache_extents() to ext4_cache_extents() since this
newly added function is not in extents_cache.c, and to avoid
potential visual confusion with ext4_es_cache_extent(). -TYT ]
Signed-off-by: Dmitry Monakhov <dmonakhov@gmail.com>
Link: https://lore.kernel.org/r/20191106122502.19986-1-dmonakhov@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
For clarity, add braces to the loop in ext4_ext_drop_refs().
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-9-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Clean up some code that was using 2-character indents.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-8-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Support for unwritten extents was added to ext4 a long time ago, so
remove a misleading comment that says they're a future feature.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-7-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Don't mention the nonexistent return value, and mention both types of
merges that are attempted.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-6-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Make the following functions static since they're only used in
extents.c:
__ext4_ext_dirty()
ext4_can_extents_be_merged()
ext4_collapse_range()
ext4_insert_range()
Also remove the prototype for ext4_ext_writepage_trans_blocks(), as this
function is not defined anywhere.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-5-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
ext4_fallocate() is only used in the file_operations for regular files.
Also, the VFS only allows fallocate() on regular files and block
devices, but block devices always use blkdev_fallocate(). For both of
these reasons, S_ISREG() is always true in ext4_fallocate().
Therefore the S_ISREG() checks in ext4_zero_range(),
ext4_collapse_range(), ext4_insert_range(), and ext4_punch_hole() are
redundant. Remove them.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-4-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
- Fix some comments.
- Consistently access i_size directly rather than using i_size_read(),
since in all relevant cases we're under inode_lock().
- Simplify the alignment checks by using the IS_ALIGNED() macro.
- In ext4_insert_range(), do the check against s_maxbytes in a way
that is safe against signed overflow. (This doesn't currently matter
for ext4 due to ext4's limited max file size, but this is something
other filesystems have gotten wrong. We might as well do it safely.)
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-3-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Remove the ext4_ind_calc_metadata_amount() and
ext4_ext_calc_metadata_amount() functions, which have been unused since
commit 71d4f7d032 ("ext4: remove metadata reservation checks").
Also remove the i_da_metadata_calc_last_lblock and
i_da_metadata_calc_len fields from struct ext4_inode_info, as these were
only used by these removed functions.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191231180444.46586-2-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Reviewed-by: Jan Kara <jack@suse.cz>
For encrypted files, commit 36086d43f6 ("ext4 crypto: fix bugs in
ext4_encrypted_zeroout()") disabled the optimization where when a write
occurs to the middle of an unwritten extent, the head and/or tail of the
extent (when they aren't too large) are zeroed out, turned into an
initialized extent, and merged with the part being written to. This
optimization helps prevent fragmentation of the extent tree.
However, disabling this optimization also made fscrypt_zeroout_range()
nearly impossible to test, as now it's only reachable via the very rare
case in ext4_split_extent_at() where allocating a new extent tree block
fails due to ENOSPC. 'gce-xfstests -c ext4/encrypt -g auto' doesn't
even hit this at all.
It's preferable to avoid really rare cases that are hard to test.
That commit also cited data corruption in xfstest generic/127 as a
reason to disable the extent zeroout optimization, but that's no longer
reproducible anymore. It also cited fscrypt_zeroout_range() having poor
performance, but I've written a patch to fix that.
Therefore, re-enable the extent zeroout optimization on encrypted files.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191226161114.53606-1-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When ext4 encryption support was first added, ZERO_RANGE was disallowed,
supposedly because test failures (e.g. ext4/001) were seen when enabling
it, and at the time there wasn't enough time/interest to debug it.
However, there's actually no reason why ZERO_RANGE can't work on
encrypted files. And it fact it *does* work now. Whole blocks in the
zeroed range are converted to unwritten extents, as usual; encryption
makes no difference for that part. Partial blocks are zeroed in the
pagecache and then ->writepages() encrypts those blocks as usual.
ext4_block_zero_page_range() handles reading and decrypting the block if
needed before actually doing the pagecache write.
Also, f2fs has always supported ZERO_RANGE on encrypted files.
As far as I can tell, the reason that ext4/001 was failing in v4.1 was
actually because of one of the bugs fixed by commit 36086d43f6 ("ext4
crypto: fix bugs in ext4_encrypted_zeroout()"). The bug made
ext4_encrypted_zeroout() always return a positive value, which caused
unwritten extents in encrypted files to sometimes not be marked as
initialized after being written to. This bug was not actually in
ZERO_RANGE; it just happened to trigger during the extents manipulation
done in ext4/001 (and probably other tests too).
So, let's enable ZERO_RANGE on encrypted files on ext4.
Tested with:
gce-xfstests -c ext4/encrypt -g auto
gce-xfstests -c ext4/encrypt_1k -g auto
Got the same set of test failures both with and without this patch.
But with this patch 6 fewer tests are skipped: ext4/001, generic/008,
generic/009, generic/033, generic/096, and generic/511.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20191226154216.4808-1-ebiggers@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This allows the cause of an ext4_error() report to be categorized
based on whether it was triggered due to an I/O error, or an memory
allocation error, or other possible causes. Most errors are caused by
a detected file system inconsistency, so the default code stored in
the superblock will be EXT4_ERR_EFSCORRUPTED.
Link: https://lore.kernel.org/r/20191204032335.7683-1-tytso@mit.edu
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
So far we have reserved only relatively high fixed amount of revoke
credits for each transaction. We over-reserved by large amount for most
cases but when freeing large directories or files with data journalling,
the fixed amount is not enough. In fact the worst case estimate is
inconveniently large (maximum extent size) for freeing of one extent.
We fix this by doing proper estimate of the amount of blocks that need
to be revoked when removing blocks from the inode due to truncate or
hole punching and otherwise reserve just a small amount of revoke
credits for each transaction to accommodate freeing of xattrs block or
so.
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-23-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Provide ext4_journal_ensure_credits_fn() function to ensure transaction
has given amount of credits and call helper function to prepare for
restarting a transaction. This allows to remove some boilerplate code
from various places, add proper error handling for the case where
transaction extension or restart fails, and reduces following changes
needed for proper revoke record reservation tracking.
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-10-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This patch introduces a new direct I/O write path which makes use of
the iomap infrastructure.
All direct I/O writes are now passed from the ->write_iter() callback
through to the new direct I/O handler ext4_dio_write_iter(). This
function is responsible for calling into the iomap infrastructure via
iomap_dio_rw().
Code snippets from the existing direct I/O write code within
ext4_file_write_iter() such as, checking whether the I/O request is
unaligned asynchronous I/O, or whether the write will result in an
overwrite have effectively been moved out and into the new direct I/O
->write_iter() handler.
The block mapping flags that are eventually passed down to
ext4_map_blocks() from the *_get_block_*() suite of routines have been
taken out and introduced within ext4_iomap_alloc().
For inode extension cases, ext4_handle_inode_extension() is
effectively the function responsible for performing such metadata
updates. This is called after iomap_dio_rw() has returned so that we
can safely determine whether we need to potentially truncate any
allocated blocks that may have been prepared for this direct I/O
write. We don't perform the inode extension, or truncate operations
from the ->end_io() handler as we don't have the original I/O 'length'
available there. The ->end_io() however is responsible fo converting
allocated unwritten extents to written extents.
In the instance of a short write, we fallback and complete the
remainder of the I/O using buffered I/O via
ext4_buffered_write_iter().
The existing buffer_head direct I/O implementation has been removed as
it's now redundant.
[ Fix up ext4_dio_write_iter() per Jan's comments at
https://lore.kernel.org/r/20191105135932.GN22379@quack2.suse.cz -- TYT ]
Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/e55db6f12ae6ff017f36774135e79f3e7b0333da.1572949325.git.mbobrowski@mbobrowski.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This patch adds the support for blocksize < pagesize for
dioread_nolock feature.
Since in case of blocksize < pagesize, we can have multiple
small buffers of page as unwritten extents, we need to
maintain a vector of these unwritten extents which needs
the conversion after the IO is complete. Thus, we maintain
a list of tuple <offset, size> pair (io_end_vec) for this &
traverse this list to do the unwritten to written conversion.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20191016073711.4141-5-riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This patch just brings in the API for conversion of unwritten io_end_vec
extents which will be required for blocksize < pagesize support
for dioread_nolock feature.
No functional changes in this patch.
Signed-off-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20191016073711.4141-3-riteshh@linux.ibm.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Really enable warning when CONFIG_EXT4_DEBUG is set and fix missing
first argument. This was introduced in commit ff95ec22cd ("ext4:
add warning to ext4_convert_unwritten_extents_endio") and splitting
extents inside endio would trigger it.
Fixes: ff95ec22cd ("ext4: add warning to ext4_convert_unwritten_extents_endio")
Signed-off-by: Rakesh Pandit <rakesh@tuxera.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
For debugging reasons, it's useful to know the contents of the extent
cache. Since the extent cache contains much of what is in the fiemap
ioctl, use an fiemap-style interface to return this information.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Since the journal inode is already checked when we added it to the
block validity's system zone, if we check it again, we'll just trigger
a failure.
This was causing failures like this:
[ 53.897001] EXT4-fs error (device sda): ext4_find_extent:909: inode
#8: comm jbd2/sda-8: pblk 121667583 bad header/extent: invalid extent entries - magic f30a, entries 8, max 340(340), depth 0(0)
[ 53.931430] jbd2_journal_bmap: journal block not found at offset 49 on sda-8
[ 53.938480] Aborting journal on device sda-8.
... but only if the system was under enough memory pressure that
logical->physical mapping for the journal inode gets pushed out of the
extent cache. (This is why it wasn't noticed earlier.)
Fixes: 345c0dbf3a ("ext4: protect journal inode's blocks using block_validity")
Reported-by: Dan Rue <dan.rue@linaro.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
This commit zeroes out the unused memory region in the buffer_head
corresponding to the extent metablock after writing the extent header
and the corresponding extent node entries.
This is done to prevent random uninitialized data from getting into
the filesystem when the extent block is synced.
This fixes CVE-2019-11833.
Signed-off-by: Sriram Rajagopalan <sriramr@arista.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
users to more easily find the jbd2 journal thread for a particular
ext4 file system.
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Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o:
"A large number of bug fixes and cleanups.
One new feature to allow users to more easily find the jbd2 journal
thread for a particular ext4 file system"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (25 commits)
jbd2: jbd2_get_transaction does not need to return a value
jbd2: fix invalid descriptor block checksum
ext4: fix bigalloc cluster freeing when hole punching under load
ext4: add sysfs attr /sys/fs/ext4/<disk>/journal_task
ext4: Change debugging support help prefix from EXT4 to Ext4
ext4: fix compile error when using BUFFER_TRACE
jbd2: fix compile warning when using JBUFFER_TRACE
ext4: fix some error pointer dereferences
ext4: annotate more implicit fall throughs
ext4: annotate implicit fall throughs
ext4: don't update s_rev_level if not required
jbd2: fold jbd2_superblock_csum_{verify,set} into their callers
jbd2: fix race when writing superblock
ext4: fix crash during online resizing
ext4: disallow files with EXT4_JOURNAL_DATA_FL from EXT4_IOC_SWAP_BOOT
ext4: add mask of ext4 flags to swap
ext4: update quota information while swapping boot loader inode
ext4: cleanup pagecache before swap i_data
ext4: fix check of inode in swap_inode_boot_loader
ext4: unlock unused_pages timely when doing writeback
...
Ext4 may not free clusters correctly when punching holes in bigalloc
file systems under high load conditions. If it's not possible to
extend and restart the journal in ext4_ext_rm_leaf() when preparing to
remove blocks from a punched region, a retry of the entire punch
operation is triggered in ext4_ext_remove_space(). This causes a
partial cluster to be set to the first cluster in the extent found to
the right of the punched region. However, if the punch operation
prior to the retry had made enough progress to delete one or more
extents and a partial cluster candidate for freeing had already been
recorded, the retry would overwrite the partial cluster. The loss of
this information makes it impossible to correctly free the original
partial cluster in all cases.
This bug can cause generic/476 to fail when run as part of
xfstests-bld's bigalloc and bigalloc_1k test cases. The failure is
reported when e2fsck detects bad iblocks counts greater than expected
in units of whole clusters and also detects a number of negative block
bitmap differences equal to the iblocks discrepancy in cluster units.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Now, we have already handle all cases of forgetting buffer in
jbd2_journal_forget(), the buffer should not be mapped to blockdevice
when reallocating it. So this patch remove all clean_bdev_aliases() and
clean_bdev_bh_alias() calls which were invoked by ext4 explicitly.
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
This commit removes the ext4 specific ext4_encrypted_inode() and makes
use of the generic IS_ENCRYPTED() macro to check for the encryption
status of an inode.
Reviewed-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Modify ext4_ext_remove_space() and the code it calls to correct the
reserved cluster count for pending reservations (delayed allocated
clusters shared with allocated blocks) when a block range is removed
from the extent tree. Pending reservations may be found for the clusters
at the ends of written or unwritten extents when a block range is removed.
If a physical cluster at the end of an extent is freed, it's necessary
to increment the reserved cluster count to maintain correct accounting
if the corresponding logical cluster is shared with at least one
delayed and unwritten extent as found in the extents status tree.
Add a new function, ext4_rereserve_cluster(), to reapply a reservation
on a delayed allocated cluster sharing blocks with a freed allocated
cluster. To avoid ENOSPC on reservation, a flag is applied to
ext4_free_blocks() to briefly defer updating the freeclusters counter
when an allocated cluster is freed. This prevents another thread
from allocating the freed block before the reservation can be reapplied.
Redefine the partial cluster object as a struct to carry more state
information and to clarify the code using it.
Adjust the conditional code structure in ext4_ext_remove_space to
reduce the indentation level in the main body of the code to improve
readability.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Ext4 does not always reduce the reserved cluster count by the number
of clusters allocated when mapping a delayed extent. It sometimes
adds back one or more clusters after allocation if delalloc blocks
adjacent to the range allocated by ext4_ext_map_blocks() share the
clusters newly allocated for that range. However, this overcounts
the number of clusters needed to satisfy future mapping requests
(holding one or more reservations for clusters that have already been
allocated) and premature ENOSPC and quota failures, etc., result.
Ext4 also does not reduce the reserved cluster count when allocating
clusters for non-delayed allocated writes that have previously been
reserved for delayed writes. This also results in overcounts.
To make it possible to handle reserved cluster accounting for
fallocated regions in the same manner as used for other non-delayed
writes, do the reserved cluster accounting for them at the time of
allocation. In the current code, this is only done later when a
delayed extent sharing the fallocated region is finally mapped.
Address comment correcting handling of unsigned long long constant
from Jan Kara's review of RFC version of this patch.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The code in ext4_da_map_blocks sometimes reserves space for more
delayed allocated clusters than it should, resulting in premature
ENOSPC, exceeded quota, and inaccurate free space reporting.
Fix this by checking for written and unwritten blocks shared in the
same cluster with the newly delayed allocated block. A cluster
reservation should not be made for a cluster for which physical space
has already been allocated.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Ext4 contains a few functions that are used to search for delayed
extents or blocks in the extents status tree. Rather than duplicate
code to add new functions to search for extents with different status
values, such as written or a combination of delayed and unwritten,
generalize the existing code to search for caller-specified extents
status values. Also, move this code into extents_status.c where it
is better associated with the data structures it operates upon, and
where it can be more readily used to implement new extents status tree
functions that might want a broader scope for i_es_lock.
Three missing static specifiers in RFC version of patch reported and
fixed by Fengguang Wu <fengguang.wu@intel.com>.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Follow the lead of xfs_break_dax_layouts() and add synchronization between
operations in ext4 which remove blocks from an inode (hole punch, truncate
down, etc.) and pages which are pinned due to DAX DMA operations.
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
maliciously crafted file system image can result in a kernel OOPS or
hang. At least one fix addresses an inline data bug could be
triggered by userspace without the need of a crafted file system
(although it does require that the inline data feature be enabled).
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 bugfixes from Ted Ts'o:
"Bug fixes for ext4; most of which relate to vulnerabilities where a
maliciously crafted file system image can result in a kernel OOPS or
hang.
At least one fix addresses an inline data bug could be triggered by
userspace without the need of a crafted file system (although it does
require that the inline data feature be enabled)"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: check superblock mapped prior to committing
ext4: add more mount time checks of the superblock
ext4: add more inode number paranoia checks
ext4: avoid running out of journal credits when appending to an inline file
jbd2: don't mark block as modified if the handle is out of credits
ext4: never move the system.data xattr out of the inode body
ext4: clear i_data in ext4_inode_info when removing inline data
ext4: include the illegal physical block in the bad map ext4_error msg
ext4: verify the depth of extent tree in ext4_find_extent()
ext4: only look at the bg_flags field if it is valid
ext4: make sure bitmaps and the inode table don't overlap with bg descriptors
ext4: always check block group bounds in ext4_init_block_bitmap()
ext4: always verify the magic number in xattr blocks
ext4: add corruption check in ext4_xattr_set_entry()
ext4: add warn_on_error mount option
If there is a corupted file system where the claimed depth of the
extent tree is -1, this can cause a massive buffer overrun leading to
sadness.
This addresses CVE-2018-10877.
https://bugzilla.kernel.org/show_bug.cgi?id=199417
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
During the "insert range" fallocate operation, extents starting at the
range offset are shifted "right" (to a higher file offset) by the range
length. But, as shown by syzbot, it's not validated that this doesn't
cause extents to be shifted beyond EXT_MAX_BLOCKS. In that case
->ee_block can wrap around, corrupting the extent tree.
Fix it by returning an error if the space between the end of the last
extent and EXT4_MAX_BLOCKS is smaller than the range being inserted.
This bug can be reproduced by running the following commands when the
current directory is on an ext4 filesystem with a 4k block size:
fallocate -l 8192 file
fallocate --keep-size -o 0xfffffffe000 -l 4096 -n file
fallocate --insert-range -l 8192 file
Then after unmounting the filesystem, e2fsck reports corruption.
Reported-by: syzbot+06c885be0edcdaeab40c@syzkaller.appspotmail.com
Fixes: 331573febb ("ext4: Add support FALLOC_FL_INSERT_RANGE for fallocate")
Cc: stable@vger.kernel.org # v4.2+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
"mark_unwritten" in comment and "unwritten" in the function arguments
is mismatched.
Signed-off-by: zhenwei.pi <zhenwei.pi@youruncloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Commit 16c5468859 ("ext4: Allow parallel DIO reads") reworked the way
locking happens around parallel dio reads. This resulted in obviating
the need for EXT4_STATE_DIOREAD_LOCK flag and accompanying logic.
Currently this amounts to dead code so let's remove it. No functional
changes
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
A number of ext4 source files were skipped due because their copyright
permission statements didn't match the expected text used by the
automated conversion utilities. I've added SPDX tags for the rest.
While looking at some of these files, I've noticed that we have quite
a bit of variation on the licenses that were used --- in particular
some of the Red Hat licenses on the jbd2 files use a GPL2+ license,
and we have some files that have a LGPL-2.1 license (which was quite
surprising).
I've not attempted to do any license changes. Even if it is perfectly
legal to relicense to GPL 2.0-only for consistency's sake, that should
be done with ext4 developer community discussion.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Currently, fallocate(2) with KEEP_SIZE followed by a fdatasync(2)
then crash, we'll see wrong allocated block number (stat -c %b), the
blocks allocated beyond EOF are all lost. fstests generic/468
exposes this bug.
Commit 67a7d5f561 ("ext4: fix fdatasync(2) after extent
manipulation operations") fixed all the other extent manipulation
operation paths such as hole punch, zero range, collapse range etc.,
but forgot the fallocate case.
So similarly, fix it by recording the correct journal tid in ext4
inode in fallocate(2) path, so that ext4_sync_file() will wait for
the right tid to be committed on fdatasync(2).
This addresses the test failure in xfstests test generic/468.
Signed-off-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
If there are pending writes subject to delayed allocation, then i_size
will show size after the writes have completed, while i_disksize
contains the value of i_size on the disk (since the writes have not
been persisted to disk).
If fallocate(2) is called with the FALLOC_FL_KEEP_SIZE flag, either
with or without the FALLOC_FL_ZERO_RANGE flag set, and the new size
after the fallocate(2) is between i_size and i_disksize, then after a
crash, if a journal commit has resulted in the changes made by the
fallocate() call to be persisted after a crash, but the delayed
allocation write has not resolved itself, i_size would not be updated,
and this would cause the following e2fsck complaint:
Inode 12, end of extent exceeds allowed value
(logical block 33, physical block 33441, len 7)
This can only take place on a sparse file, where the fallocate(2) call
is allocating blocks in a range which is before a pending delayed
allocation write which is extending i_size. Since this situation is
quite rare, and the window in which the crash must take place is
typically < 30 seconds, in practice this condition will rarely happen.
Nevertheless, it can be triggered in testing, and in particular by
xfstests generic/456.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported-by: Amir Goldstein <amir73il@gmail.com>
Cc: stable@vger.kernel.org
This bug was found by a static code checker tool for copy paste
problems.
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_alloc_file_blocks() does not use its mode parameter. Remove it.
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ea_inode contents are treated as metadata, that's why it is journaled
during initial writes. Failing to call revoke during freeing could cause
user data to be overwritten with original ea_inode contents during journal
replay.
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Currently, extent manipulation operations such as hole punch, range
zeroing, or extent shifting do not record the fact that file data has
changed and thus fdatasync(2) has a work to do. As a result if we crash
e.g. after a punch hole and fdatasync, user can still possibly see the
punched out data after journal replay. Test generic/392 fails due to
these problems.
Fix the problem by properly marking that file data has changed in these
operations.
CC: stable@vger.kernel.org
Fixes: a4bb6b64e3
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When ext4_map_blocks() is called with EXT4_GET_BLOCKS_ZERO to zero-out
allocated blocks and these blocks are actually converted from unwritten
extent the following race can happen:
CPU0 CPU1
page fault page fault
... ...
ext4_map_blocks()
ext4_ext_map_blocks()
ext4_ext_handle_unwritten_extents()
ext4_ext_convert_to_initialized()
- zero out converted extent
ext4_zeroout_es()
- inserts extent as initialized in status tree
ext4_map_blocks()
ext4_es_lookup_extent()
- finds initialized extent
write data
ext4_issue_zeroout()
- zeroes out new extent overwriting data
This problem can be reproduced by generic/340 for the fallocated case
for the last block in the file.
Fix the problem by avoiding zeroing out the area we are mapping with
ext4_map_blocks() in ext4_ext_convert_to_initialized(). It is pointless
to zero out this area in the first place as the caller asked us to
convert the area to initialized because he is just going to write data
there before the transaction finishes. To achieve this we delete the
special case of zeroing out full extent as that will be handled by the
cases below zeroing only the part of the extent that needs it. We also
instruct ext4_split_extent() that the middle of extent being split
contains data so that ext4_split_extent_at() cannot zero out full extent
in case of ENOSPC.
CC: stable@vger.kernel.org
Fixes: 12735f8819
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Inside ext4_ext_shift_extents() function ext4_find_extent() is called
without EXT4_EX_NOCACHE flag, which should prevent cache population.
This leads to oudated offsets in the extents tree and wrong blocks
afterwards.
Patch fixes the problem providing EXT4_EX_NOCACHE flag for each
ext4_find_extents() call inside ext4_ext_shift_extents function.
Fixes: 331573febb
Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: stable@vger.kernel.org
While doing 'insert range' start block should be also shifted right.
The bug can be easily reproduced by the following test:
ptr = malloc(4096);
assert(ptr);
fd = open("./ext4.file", O_CREAT | O_TRUNC | O_RDWR, 0600);
assert(fd >= 0);
rc = fallocate(fd, 0, 0, 8192);
assert(rc == 0);
for (i = 0; i < 2048; i++)
*((unsigned short *)ptr + i) = 0xbeef;
rc = pwrite(fd, ptr, 4096, 0);
assert(rc == 4096);
rc = pwrite(fd, ptr, 4096, 4096);
assert(rc == 4096);
for (block = 2; block < 1000; block++) {
rc = fallocate(fd, FALLOC_FL_INSERT_RANGE, 4096, 4096);
assert(rc == 0);
for (i = 0; i < 2048; i++)
*((unsigned short *)ptr + i) = block;
rc = pwrite(fd, ptr, 4096, 4096);
assert(rc == 4096);
}
Because start block is not included in the range the hole appears at
the wrong offset (just after the desired offset) and the following
pwrite() overwrites already existent block, keeping hole untouched.
Simple way to verify wrong behaviour is to check zeroed blocks after
the test:
$ hexdump ./ext4.file | grep '0000 0000'
The root cause of the bug is a wrong range (start, stop], where start
should be inclusive, i.e. [start, stop].
This patch fixes the problem by including start into the range. But
not to break left shift (range collapse) stop points to the beginning
of the a block, not to the end.
The other not obvious change is an iterator check on validness in a
main loop. Because iterator is unsigned the following corner case
should be considered with care: insert a block at 0 offset, when stop
variables overflows and never becomes less than start, which is 0.
To handle this special case iterator is set to NULL to indicate that
end of the loop is reached.
Fixes: 331573febb
Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: Namjae Jeon <namjae.jeon@samsung.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: stable@vger.kernel.org
