Merge active entropy generation updates.
This is admittedly partly "for discussion". We need to have a way
forward for the boot time deadlocks where user space ends up waiting for
more entropy, but no entropy is forthcoming because the system is
entirely idle just waiting for something to happen.
While this was triggered by what is arguably a user space bug with
GDM/gnome-session asking for secure randomness during early boot, when
they didn't even need any such truly secure thing, the issue ends up
being that our "getrandom()" interface is prone to that kind of
confusion, because people don't think very hard about whether they want
to block for sufficient amounts of entropy.
The approach here-in is to decide to not just passively wait for entropy
to happen, but to start actively collecting it if it is missing. This
is not necessarily always possible, but if the architecture has a CPU
cycle counter, there is a fair amount of noise in the exact timings of
reasonably complex loads.
We may end up tweaking the load and the entropy estimates, but this
should be at least a reasonable starting point.
As part of this, we also revert the revert of the ext4 IO pattern
improvement that ended up triggering the reported lack of external
entropy.
* getrandom() active entropy waiting:
Revert "Revert "ext4: make __ext4_get_inode_loc plug""
random: try to actively add entropy rather than passively wait for it
This reverts commit 72dbcf7215.
Instead of waiting forever for entropy that may just not happen, we now
try to actively generate entropy when required, and are thus hopefully
avoiding the problem that caused the nice ext4 IO pattern fix to be
reverted.
So revert the revert.
Cc: Ahmed S. Darwish <darwish.07@gmail.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Alexander E. Patrakov <patrakov@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
about the state of the extent status cache.
Dropped workaround for pre-1970 dates which were encoded incorrectly
in pre-4.4 kernels. Since both the kernel correctly generates, and
e2fsck detects and fixes this issue for the past four years, it'e time
to drop the workaround. (Also, it's not like files with dates in the
distant past were all that common in the first place.)
A lot of miscellaneous bug fixes and cleanups, including some ext4
Documentation fixes. Also included are two minor bug fixes in
fs/unicode.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAl2D5ZIACgkQ8vlZVpUN
gaO8NQf+ONLK5nu8KUk14uh8MOXMisiT+g1iqhynZcqtuZzTr4nKqUbHLmPDHrCC
RiD/gkLhp6u+UlzYRJq6nudunid1be2/1bjoUm6lddE4XLtbeGHhZsGn1+9K/wy+
l8UFMXd8fCOlXNzajS85Hb0KSuzlrGYEjSrNecSa3KLxrv1kM1+FyKFcqQ7Ejs5/
VZYNtWo69R4wSEIawGkEZuNu/wFeLOzqJgxFJLo6zFxTAp449bbEduz12ssmkUhl
QbXH9cXLR4pAZykzMRqHC8UFFTKmpLnc5EiT1Ajxzu4EAzB1SzqRJvbz/3CF3d/Z
gBKDrDlasv75VJqVtqw4mCxmEoEYjw==
=Iwrf
-----END PGP SIGNATURE-----
Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o:
"Added new ext4 debugging ioctls to allow userspace to get information
about the state of the extent status cache.
Dropped workaround for pre-1970 dates which were encoded incorrectly
in pre-4.4 kernels. Since both the kernel correctly generates, and
e2fsck detects and fixes this issue for the past four years, it'e time
to drop the workaround. (Also, it's not like files with dates in the
distant past were all that common in the first place.)
A lot of miscellaneous bug fixes and cleanups, including some ext4
Documentation fixes. Also included are two minor bug fixes in
fs/unicode"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (21 commits)
unicode: make array 'token' static const, makes object smaller
unicode: Move static keyword to the front of declarations
ext4: add missing bigalloc documentation.
ext4: fix kernel oops caused by spurious casefold flag
ext4: fix integer overflow when calculating commit interval
ext4: use percpu_counters for extent_status cache hits/misses
ext4: fix potential use after free after remounting with noblock_validity
jbd2: add missing tracepoint for reserved handle
ext4: fix punch hole for inline_data file systems
ext4: rework reserved cluster accounting when invalidating pages
ext4: documentation fixes
ext4: treat buffers with write errors as containing valid data
ext4: fix warning inside ext4_convert_unwritten_extents_endio
ext4: set error return correctly when ext4_htree_store_dirent fails
ext4: drop legacy pre-1970 encoding workaround
ext4: add new ioctl EXT4_IOC_GET_ES_CACHE
ext4: add a new ioctl EXT4_IOC_GETSTATE
ext4: add a new ioctl EXT4_IOC_CLEAR_ES_CACHE
jbd2: flush_descriptor(): Do not decrease buffer head's ref count
ext4: remove unnecessary error check
...
Please consider pulling fs-verity for 5.4.
fs-verity is a filesystem feature that provides Merkle tree based
hashing (similar to dm-verity) for individual readonly files, mainly for
the purpose of efficient authenticity verification.
This pull request includes:
(a) The fs/verity/ support layer and documentation.
(b) fs-verity support for ext4 and f2fs.
Compared to the original fs-verity patchset from last year, the UAPI to
enable fs-verity on a file has been greatly simplified. Lots of other
things were cleaned up too.
fs-verity is planned to be used by two different projects on Android;
most of the userspace code is in place already. Another userspace tool
("fsverity-utils"), and xfstests, are also available. e2fsprogs and
f2fs-tools already have fs-verity support. Other people have shown
interest in using fs-verity too.
I've tested this on ext4 and f2fs with xfstests, both the existing tests
and the new fs-verity tests. This has also been in linux-next since
July 30 with no reported issues except a couple minor ones I found
myself and folded in fixes for.
Ted and I will be co-maintaining fs-verity.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQSacvsUNc7UX4ntmEPzXCl4vpKOKwUCXX8ZUBQcZWJpZ2dlcnNA
Z29vZ2xlLmNvbQAKCRDzXCl4vpKOK2YOAQCbnBAKWDxXS3alLARRwjQLjmEtQIGl
gsek+WurFIg/zAEAlpSzHwu13LvYzTqv3rhO2yhSlvhnDu4GQEJPXPm0wgM=
=ID0n
-----END PGP SIGNATURE-----
Merge tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt
Pull fs-verity support from Eric Biggers:
"fs-verity is a filesystem feature that provides Merkle tree based
hashing (similar to dm-verity) for individual readonly files, mainly
for the purpose of efficient authenticity verification.
This pull request includes:
(a) The fs/verity/ support layer and documentation.
(b) fs-verity support for ext4 and f2fs.
Compared to the original fs-verity patchset from last year, the UAPI
to enable fs-verity on a file has been greatly simplified. Lots of
other things were cleaned up too.
fs-verity is planned to be used by two different projects on Android;
most of the userspace code is in place already. Another userspace tool
("fsverity-utils"), and xfstests, are also available. e2fsprogs and
f2fs-tools already have fs-verity support. Other people have shown
interest in using fs-verity too.
I've tested this on ext4 and f2fs with xfstests, both the existing
tests and the new fs-verity tests. This has also been in linux-next
since July 30 with no reported issues except a couple minor ones I
found myself and folded in fixes for.
Ted and I will be co-maintaining fs-verity"
* tag 'fsverity-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
f2fs: add fs-verity support
ext4: update on-disk format documentation for fs-verity
ext4: add fs-verity read support
ext4: add basic fs-verity support
fs-verity: support builtin file signatures
fs-verity: add SHA-512 support
fs-verity: implement FS_IOC_MEASURE_VERITY ioctl
fs-verity: implement FS_IOC_ENABLE_VERITY ioctl
fs-verity: add data verification hooks for ->readpages()
fs-verity: add the hook for file ->setattr()
fs-verity: add the hook for file ->open()
fs-verity: add inode and superblock fields
fs-verity: add Kconfig and the helper functions for hashing
fs: uapi: define verity bit for FS_IOC_GETFLAGS
fs-verity: add UAPI header
fs-verity: add MAINTAINERS file entry
fs-verity: add a documentation file
This reverts commit b03755ad6f.
This is sad, and done for all the wrong reasons. Because that commit is
good, and does exactly what it says: avoids a lot of small disk requests
for the inode table read-ahead.
However, it turns out that it causes an entirely unrelated problem: the
getrandom() system call was introduced back in 2014 by commit
c6e9d6f388 ("random: introduce getrandom(2) system call"), and people
use it as a convenient source of good random numbers.
But part of the current semantics for getrandom() is that it waits for
the entropy pool to fill at least partially (unlike /dev/urandom). And
at least ArchLinux apparently has a systemd that uses getrandom() at
boot time, and the improvements in IO patterns means that existing
installations suddenly start hanging, waiting for entropy that will
never happen.
It seems to be an unlucky combination of not _quite_ enough entropy,
together with a particular systemd version and configuration. Lennart
says that the systemd-random-seed process (which is what does this early
access) is supposed to not block any other boot activity, but sadly that
doesn't actually seem to be the case (possibly due bogus dependencies on
cryptsetup for encrypted swapspace).
The correct fix is to fix getrandom() to not block when it's not
appropriate, but that fix is going to take a lot more discussion. Do we
just make it act like /dev/urandom by default, and add a new flag for
"wait for entropy"? Do we add a boot-time option? Or do we just limit
the amount of time it will wait for entropy?
So in the meantime, we do the revert to give us time to discuss the
eventual fix for the fundamental problem, at which point we can re-apply
the ext4 inode table access optimization.
Reported-by: Ahmed S. Darwish <darwish.07@gmail.com>
Cc: Ted Ts'o <tytso@mit.edu>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Alexander E. Patrakov <patrakov@gmail.com>
Cc: Lennart Poettering <mzxreary@0pointer.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If an directory has the a casefold flag set without the casefold
feature set, s_encoding will not be initialized, and this will cause
the kernel to dereference a NULL pointer. In addition to adding
checks to avoid these kernel oops, attempts to load inodes with the
casefold flag when the casefold feature is not enable will cause the
file system to be declared corrupted.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
If a program attempts to punch a hole on an inline data file, we need
to convert it to a normal file first.
This was detected using ext4/032 using the adv configuration. Simple
reproducer:
mke2fs -Fq -t ext4 -O inline_data /dev/vdc
mount /vdc
echo "" > /vdc/testfile
xfs_io -c 'truncate 33554432' /vdc/testfile
xfs_io -c 'fpunch 0 1048576' /vdc/testfile
umount /vdc
e2fsck -fy /dev/vdc
Cc: stable@vger.kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The goal of this patch is to remove two references to the buffer delay
bit in ext4_da_page_release_reservation() as part of a larger effort
to remove all such references from ext4. These two references are
principally used to reduce the reserved block/cluster count when pages
are invalidated as a result of truncating, punching holes, or
collapsing a block range in a file. The entire function is removed
and replaced with code in ext4_es_remove_extent() that reduces the
reserved count as a side effect of removing a block range from delayed
and not unwritten extents in the extent status tree as is done when
truncating, punching holes, or collapsing ranges.
The code is written to minimize the number of searches descending from
rb tree roots for scalability.
Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
I got some errors when I repair an ext4 volume which stacked by an
iscsi target:
Entry 'test60' in / (2) has deleted/unused inode 73750. Clear?
It can be reproduced when the network not good enough.
When I debug this I found ext4 will read entry buffer from disk and
the buffer is marked with write_io_error.
If the buffer is marked with write_io_error, it means it already
wroten to journal, and not checked out to disk. IOW, the journal
is newer than the data in disk.
If this journal record 'delete test60', it means the 'test60' still
on the disk metadata.
In this case, if we read the buffer from disk successfully and create
file continue, the new journal record will overwrite the journal
which record 'delete test60', then the entry corruptioned.
So, use the buffer rather than read from disk if the buffer is marked
with write_io_error.
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Make ext4_mpage_readpages() verify data as it is read from fs-verity
files, using the helper functions from fs/verity/.
To support both encryption and verity simultaneously, this required
refactoring the decryption workflow into a generic "post-read
processing" workflow which can do decryption, verification, or both.
The case where the ext4 block size is not equal to the PAGE_SIZE is not
supported yet, since in that case ext4_mpage_readpages() sometimes falls
back to block_read_full_page(), which does not support fs-verity yet.
Co-developed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Add most of fs-verity support to ext4. fs-verity is a filesystem
feature that enables transparent integrity protection and authentication
of read-only files. It uses a dm-verity like mechanism at the file
level: a Merkle tree is used to verify any block in the file in
log(filesize) time. It is implemented mainly by helper functions in
fs/verity/. See Documentation/filesystems/fsverity.rst for the full
documentation.
This commit adds all of ext4 fs-verity support except for the actual
data verification, including:
- Adding a filesystem feature flag and an inode flag for fs-verity.
- Implementing the fsverity_operations to support enabling verity on an
inode and reading/writing the verity metadata.
- Updating ->write_begin(), ->write_end(), and ->writepages() to support
writing verity metadata pages.
- Calling the fs-verity hooks for ->open(), ->setattr(), and ->ioctl().
ext4 stores the verity metadata (Merkle tree and fsverity_descriptor)
past the end of the file, starting at the first 64K boundary beyond
i_size. This approach works because (a) verity files are readonly, and
(b) pages fully beyond i_size aren't visible to userspace but can be
read/written internally by ext4 with only some relatively small changes
to ext4. This approach avoids having to depend on the EA_INODE feature
and on rearchitecturing ext4's xattr support to support paging
multi-gigabyte xattrs into memory, and to support encrypting xattrs.
Note that the verity metadata *must* be encrypted when the file is,
since it contains hashes of the plaintext data.
This patch incorporates work by Theodore Ts'o and Chandan Rajendra.
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Eric Biggers <ebiggers@google.com>
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>
mkfs.ext4 -O inline_data /dev/vdb
mount -o dioread_nolock /dev/vdb /mnt
echo "some inline data..." >> /mnt/test-file
echo "some inline data..." >> /mnt/test-file
sync
The above script will trigger "WARN_ON(!io_end->handle && sbi->s_journal)"
because ext4_should_dioread_nolock() returns false for a file with inline
data. Move the check to a place after we have already removed the inline
data and prepared inode to write normal pages.
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
lookups.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAl0lFIoACgkQ8vlZVpUN
gaOwNQf/aJxFxHVf4t3lga8kfoMhlbwINQknsGUVwg32HporMa1NxQXjbEMMhs6V
A31gBJ44nYVz1enz7nvbE4kx4quF4E8rDVprEetphv4i8GSdUAihwJwY5/H0oSd8
rxzTZzNKddoyN/j7H4LgAh7bo6IFk54kUuaAWuZDJnJtfLNQ6RBaIwg6u6Z8Fael
9H3u/RtFHqWPQp5j50PMUG06abr26GKi1gLL+yeoFD1tuzC54B5i6uy34amrXlon
5agIQ7YuB9bigK4VaLoF4df7o+7+Oa6ENaQ9O/TQc9Uy9ngdVlPpNb2bVDizRLNn
e369sBFTf3C8sMycJy6x9TCqg2B7Hw==
=EpCF
-----END PGP SIGNATURE-----
Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o:
"Many bug fixes and cleanups, and an optimization for case-insensitive
lookups"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: fix coverity warning on error path of filename setup
ext4: replace ktype default_attrs with default_groups
ext4: rename htree_inline_dir_to_tree() to ext4_inlinedir_to_tree()
ext4: refactor initialize_dirent_tail()
ext4: rename "dirent_csum" functions to use "dirblock"
ext4: allow directory holes
jbd2: drop declaration of journal_sync_buffer()
ext4: use jbd2_inode dirty range scoping
jbd2: introduce jbd2_inode dirty range scoping
mm: add filemap_fdatawait_range_keep_errors()
ext4: remove redundant assignment to node
ext4: optimize case-insensitive lookups
ext4: make __ext4_get_inode_loc plug
ext4: clean up kerneldoc warnigns when building with W=1
ext4: only set project inherit bit for directory
ext4: enforce the immutable flag on open files
ext4: don't allow any modifications to an immutable file
jbd2: fix typo in comment of journal_submit_inode_data_buffers
jbd2: fix some print format mistakes
ext4: gracefully handle ext4_break_layouts() failure during truncate
Use the newly introduced jbd2_inode dirty range scoping to prevent us
from waiting forever when trying to complete a journal transaction.
Signed-off-by: Ross Zwisler <zwisler@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: stable@vger.kernel.org
Add a blk_plug to prevent the inode table readahead from being
submitted as small I/O requests.
Signed-off-by: zhangjs <zachary@baishancloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
According to the chattr man page, "a file with the 'i' attribute
cannot be modified..." Historically, this was only enforced when the
file was opened, per the rest of the description, "... and the file
can not be opened in write mode".
There is general agreement that we should standardize all file systems
to prevent modifications even for files that were opened at the time
the immutable flag is set. Eventually, a change to enforce this at
the VFS layer should be landing in mainline. Until then, enforce this
at the ext4 level to prevent xfstests generic/553 from failing.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: "Darrick J. Wong" <darrick.wong@oracle.com>
Cc: stable@kernel.org
ext4_break_layouts() may fail e.g. due to a signal being delivered.
Thus we need to handle its failure gracefully and not by taking the
filesystem down. Currently ext4_break_layouts() failure is rare but it
may become more common once RDMA uses layout leases for handling
long-term page pins for DAX mappings.
To handle the failure we need to move ext4_break_layouts() earlier
during setattr handling before we do hard to undo changes such as
modifying inode size. To be able to do that we also have to move some
other checks which are better done without holding i_mmap_sem earlier.
Reported-and-tested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In __ext4_block_zero_page_range(), only decrypt the block that actually
needs to be decrypted, rather than assuming blocksize == PAGE_SIZE and
decrypting the whole page.
This is in preparation for allowing encryption on ext4 filesystems with
blocksize != PAGE_SIZE.
Signed-off-by: Chandan Rajendra <chandan@linux.ibm.com>
(EB: rebase onto previous changes, improve the commit message, and use
bh_offset())
Signed-off-by: Eric Biggers <ebiggers@google.com>
In ext4_block_write_begin(), only decrypt the blocks that actually need
to be decrypted (up to two blocks which intersect the boundaries of the
region that will be written to), rather than assuming blocksize ==
PAGE_SIZE and decrypting the whole page.
This is in preparation for allowing encryption on ext4 filesystems with
blocksize != PAGE_SIZE.
Signed-off-by: Chandan Rajendra <chandan@linux.ibm.com>
(EB: rebase onto previous changes, improve the commit message,
and move the check for encrypted inode)
Signed-off-by: Eric Biggers <ebiggers@google.com>
If decryption fails, ext4_block_write_begin() can return with the page's
buffer_head marked with the BH_Uptodate flag. This commit clears the
BH_Uptodate flag in such cases.
Signed-off-by: Chandan Rajendra <chandan@linux.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Rename fscrypt_decrypt_page() to fscrypt_decrypt_pagecache_blocks() and
redefine its behavior to decrypt all filesystem blocks in the given
region of the given page, rather than assuming that the region consists
of just one filesystem block. Also remove the 'inode' and 'lblk_num'
parameters, since they can be retrieved from the page as it's already
assumed to be a pagecache page.
This is in preparation for allowing encryption on ext4 filesystems with
blocksize != PAGE_SIZE.
This is based on work by Chandan Rajendra.
Reviewed-by: Chandan Rajendra <chandan@linux.ibm.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
It is possible that unlinked inode enters ext4_setattr() (e.g. if
somebody calls ftruncate(2) on unlinked but still open file). In such
case we should not delete the inode from the orphan list if truncate
fails. Note that this is mostly a theoretical concern as filesystem is
corrupted if we reach this path anyway but let's be consistent in our
orphan handling.
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
We didn't wait for outstanding direct IO during truncate in nojournal
mode (as we skip orphan handling in that case). This can lead to fs
corruption or stale data exposure if truncate ends up freeing blocks
and these get reallocated before direct IO finishes. Fix the condition
determining whether the wait is necessary.
CC: stable@vger.kernel.org
Fixes: 1c9114f9c0 ("ext4: serialize unlocked dio reads with truncate")
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This patch implements the actual support for case-insensitive file name
lookups in ext4, based on the feature bit and the encoding stored in the
superblock.
A filesystem that has the casefold feature set is able to configure
directories with the +F (EXT4_CASEFOLD_FL) attribute, enabling lookups
to succeed in that directory in a case-insensitive fashion, i.e: match
a directory entry even if the name used by userspace is not a byte per
byte match with the disk name, but is an equivalent case-insensitive
version of the Unicode string. This operation is called a
case-insensitive file name lookup.
The feature is configured as an inode attribute applied to directories
and inherited by its children. This attribute can only be enabled on
empty directories for filesystems that support the encoding feature,
thus preventing collision of file names that only differ by case.
* dcache handling:
For a +F directory, Ext4 only stores the first equivalent name dentry
used in the dcache. This is done to prevent unintentional duplication of
dentries in the dcache, while also allowing the VFS code to quickly find
the right entry in the cache despite which equivalent string was used in
a previous lookup, without having to resort to ->lookup().
d_hash() of casefolded directories is implemented as the hash of the
casefolded string, such that we always have a well-known bucket for all
the equivalencies of the same string. d_compare() uses the
utf8_strncasecmp() infrastructure, which handles the comparison of
equivalent, same case, names as well.
For now, negative lookups are not inserted in the dcache, since they
would need to be invalidated anyway, because we can't trust missing file
dentries. This is bad for performance but requires some leveraging of
the vfs layer to fix. We can live without that for now, and so does
everyone else.
* on-disk data:
Despite using a specific version of the name as the internal
representation within the dcache, the name stored and fetched from the
disk is a byte-per-byte match with what the user requested, making this
implementation 'name-preserving'. i.e. no actual information is lost
when writing to storage.
DX is supported by modifying the hashes used in +F directories to make
them case/encoding-aware. The new disk hashes are calculated as the
hash of the full casefolded string, instead of the string directly.
This allows us to efficiently search for file names in the htree without
requiring the user to provide an exact name.
* Dealing with invalid sequences:
By default, when a invalid UTF-8 sequence is identified, ext4 will treat
it as an opaque byte sequence, ignoring the encoding and reverting to
the old behavior for that unique file. This means that case-insensitive
file name lookup will not work only for that file. An optional bit can
be set in the superblock telling the filesystem code and userspace tools
to enforce the encoding. When that optional bit is set, any attempt to
create a file name using an invalid UTF-8 sequence will fail and return
an error to userspace.
* Normalization algorithm:
The UTF-8 algorithms used to compare strings in ext4 is implemented
lives in fs/unicode, and is based on a previous version developed by
SGI. It implements the Canonical decomposition (NFD) algorithm
described by the Unicode specification 12.1, or higher, combined with
the elimination of ignorable code points (NFDi) and full
case-folding (CF) as documented in fs/unicode/utf8_norm.c.
NFD seems to be the best normalization method for EXT4 because:
- It has a lower cost than NFC/NFKC (which requires
decomposing to NFD as an intermediary step)
- It doesn't eliminate important semantic meaning like
compatibility decompositions.
Although:
- This implementation is not completely linguistic accurate, because
different languages have conflicting rules, which would require the
specialization of the filesystem to a given locale, which brings all
sorts of problems for removable media and for users who use more than
one language.
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Add the blocks which belong to the journal inode to block_validity's
system zone so attempts to deallocate or overwrite the journal due a
corrupted file system where the journal blocks are also claimed by
another inode.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202879
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
BUG_ON(1) leads to bogus warnings from clang when
CONFIG_PROFILE_ANNOTATED_BRANCHES is set:
fs/ext4/inode.c:544:4: error: variable 'retval' is used uninitialized whenever 'if' condition is false
[-Werror,-Wsometimes-uninitialized]
BUG_ON(1);
^~~~~~~~~
include/asm-generic/bug.h:61:36: note: expanded from macro 'BUG_ON'
^~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:48:23: note: expanded from macro 'unlikely'
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/ext4/inode.c:591:6: note: uninitialized use occurs here
if (retval > 0 && map->m_flags & EXT4_MAP_MAPPED) {
^~~~~~
fs/ext4/inode.c:544:4: note: remove the 'if' if its condition is always true
BUG_ON(1);
^
include/asm-generic/bug.h:61:32: note: expanded from macro 'BUG_ON'
^
fs/ext4/inode.c:502:12: note: initialize the variable 'retval' to silence this warning
Change it to BUG() so clang can see that this code path can never
continue.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Jan Kara <jack@suse.cz>
This function is never used from the beginning (and is commented out);
let's remove it.
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
users to more easily find the jbd2 journal thread for a particular
ext4 file system.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAlx8utQACgkQ8vlZVpUN
gaOMOQf+Olp6hTbCuPJNill7npEejkPu9VhNvLPp3dLPBfsyqG9IOZmUaKKtr3LS
ZYYzMMoIlbHDsWM70O92zDS3s1ThKRFoDdcw4YKXkn1Awlqc4LRZ/NnzyIIdA3mK
rhOvcr6ttWk2B2S67nGceTH08SX5zACMtMiQijP58+GCp4Xe+PdqPRRjYYJSOZMv
xCS43LoWY0tkeBTQuk9WYTi6G/E1X/aiq06pYiQzP69PotN6/cFSdNgP1r+7dYiS
V4IXPqEqFt8NvUZb1bJchT3+2zM3Xi/+n//7yLkpY7OhX6p1p24oB7abMstp3ssU
BlF8KP4elQcI892QX2Hf+0r4tBu+0w==
=2yLu
-----END PGP SIGNATURE-----
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
...
Fix compile error below when using BUFFER_TRACE.
fs/ext4/inode.c: In function ‘ext4_expand_extra_isize’:
fs/ext4/inode.c:5979:19: error: request for member ‘bh’ in something not a structure or union
BUFFER_TRACE(iloc.bh, "get_write_access");
Fixes: c03b45b853 ("ext4, project: expand inode extra size if possible")
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>
Don't update the superblock s_rev_level during mount if it isn't
actually necessary, only if superblock features are being set by
the kernel. This was originally added for ext3 since it always
set the INCOMPAT_RECOVER and HAS_JOURNAL features during mount,
but this is not needed since no journal mode was added to ext4.
That will allow Geert to mount his 20-year-old ext2 rev 0.0 m68k
filesystem, as a testament of the backward compatibility of ext4.
Fixes: 0390131ba8 ("ext4: Allow ext4 to run without a journal")
Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In mpage_add_bh_to_extent(), when accumulated extents length is greater
than MAX_WRITEPAGES_EXTENT_LEN or buffer head's b_stat is not equal, we
will not continue to search unmapped area for this page, but note this
page is locked, and will only be unlocked in mpage_release_unused_pages()
after ext4_io_submit, if io also is throttled by blk-throttle or similar
io qos, we will hold this page locked for a while, it's unnecessary.
I think the best fix is to refactor mpage_add_bh_to_extent() to let it
return some hints whether to unlock this page, but given that we will
improve dioread_nolock later, we can let it done later, so currently
the simple fix would just call mpage_release_unused_pages() before
ext4_io_submit().
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.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>
There is a function which clearly conveys the objective of checking
i_writecount. Additionally the usage in ext4_mb_initialize_context was
wrong, since a node would have wrongfully been reported as writable if
i_writecount had a negative value (MMAP_DENY_WRITE).
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
In order to have a common code base for fscrypt "post read" processing
for all filesystems which support encryption, this commit removes
filesystem specific build config option (e.g. CONFIG_EXT4_FS_ENCRYPTION)
and replaces it with a build option (i.e. CONFIG_FS_ENCRYPTION) whose
value affects all the filesystems making use of fscrypt.
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>
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>
The check for special (reserved) inode number checks in __ext4_iget()
was broken by commit 8a363970d1dc: ("ext4: avoid declaring fs
inconsistent due to invalid file handles"). This was caused by a
botched reversal of the sense of the flag now known as
EXT4_IGET_SPECIAL (when it was previously named EXT4_IGET_NORMAL).
Fix the logic appropriately.
Fixes: 8a363970d1 ("ext4: avoid declaring fs inconsistent...")
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: stable@kernel.org
There are enough credits reserved for most dioread_nolock writes;
however, if the extent tree is sufficiently deep, and/or quota is
enabled, the code was not allowing for all eventualities when
reserving journal credits for the unwritten extent conversion.
This problem can be seen using xfstests ext4/034:
WARNING: CPU: 1 PID: 257 at fs/ext4/ext4_jbd2.c:271 __ext4_handle_dirty_metadata+0x10c/0x180
Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work
RIP: 0010:__ext4_handle_dirty_metadata+0x10c/0x180
...
EXT4-fs: ext4_free_blocks:4938: aborting transaction: error 28 in __ext4_handle_dirty_metadata
EXT4: jbd2_journal_dirty_metadata failed: handle type 11 started at line 4921, credits 4/0, errcode -28
EXT4-fs error (device dm-1) in ext4_free_blocks:4950: error 28
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
If the file system has been shut down or is read-only, then
ext4_write_inode() needs to bail out early.
Also use jbd2_complete_transaction() instead of ext4_force_commit() so
we only force a commit if it is needed.
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
If we receive a file handle, either from NFS or open_by_handle_at(2),
and it points at an inode which has not been initialized, and the file
system has metadata checksums enabled, we shouldn't try to get the
inode, discover the checksum is invalid, and then declare the file
system as being inconsistent.
This can be reproduced by creating a test file system via "mke2fs -t
ext4 -O metadata_csum /tmp/foo.img 8M", mounting it, cd'ing into that
directory, and then running the following program.
#define _GNU_SOURCE
#include <fcntl.h>
struct handle {
struct file_handle fh;
unsigned char fid[MAX_HANDLE_SZ];
};
int main(int argc, char **argv)
{
struct handle h = {{8, 1 }, { 12, }};
open_by_handle_at(AT_FDCWD, &h.fh, O_RDONLY);
return 0;
}
Google-Bug-Id: 120690101
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
error return cleanup paths.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAlvoFrEACgkQ8vlZVpUN
gaMTSQf+Ogrvm7pfWtXf+RkmhhuyR26T+Hwxgl51m5bKetJBjEsh0qOaIfo7etwG
aLc1x/pWng2VTCHk4z0Ij9KS8YwLK3sQCBYZoJFyT/R09yGgAhLm+xP5j38WLqrX
h4GxVgekHSATkG95N/So7F7pQiz7gDowgbaYFW3PooXPoHJnCnTzcr7TGFAQBZAw
iR+8+KtH5E8IcC7Jj40nemk7Wib45DgaeGpP5P9Ct/Jw7hW+Mwhf56NYOWkLdHyy
4Kt7rm1Sbxam8k3nksNmIwx28bw+S0Ew1zZgkwgAcKcHaWdrv3TtGPkOA26AH+S3
UVeORM7xH+zXslIOyFK+7sXUZr5LiQ==
=BaBl
-----END PGP SIGNATURE-----
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:
"A large number of ext4 bug fixes, mostly buffer and memory leaks on
error return cleanup paths"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: missing !bh check in ext4_xattr_inode_write()
ext4: fix buffer leak in __ext4_read_dirblock() on error path
ext4: fix buffer leak in ext4_expand_extra_isize_ea() on error path
ext4: fix buffer leak in ext4_xattr_move_to_block() on error path
ext4: release bs.bh before re-using in ext4_xattr_block_find()
ext4: fix buffer leak in ext4_xattr_get_block() on error path
ext4: fix possible leak of s_journal_flag_rwsem in error path
ext4: fix possible leak of sbi->s_group_desc_leak in error path
ext4: remove unneeded brelse call in ext4_xattr_inode_update_ref()
ext4: avoid possible double brelse() in add_new_gdb() on error path
ext4: avoid buffer leak in ext4_orphan_add() after prior errors
ext4: avoid buffer leak on shutdown in ext4_mark_iloc_dirty()
ext4: fix possible inode leak in the retry loop of ext4_resize_fs()
ext4: fix missing cleanup if ext4_alloc_flex_bg_array() fails while resizing
ext4: add missing brelse() update_backups()'s error path
ext4: add missing brelse() add_new_gdb_meta_bg()'s error path
ext4: add missing brelse() in set_flexbg_block_bitmap()'s error path
ext4: avoid potential extra brelse in setup_new_flex_group_blocks()
ext4_mark_iloc_dirty() callers expect that it releases iloc->bh
even if it returns an error.
Fixes: 0db1ff222d ("ext4: add shutdown bit and check for it")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org # 4.11
Pull XArray conversion from Matthew Wilcox:
"The XArray provides an improved interface to the radix tree data
structure, providing locking as part of the API, specifying GFP flags
at allocation time, eliminating preloading, less re-walking the tree,
more efficient iterations and not exposing RCU-protected pointers to
its users.
This patch set
1. Introduces the XArray implementation
2. Converts the pagecache to use it
3. Converts memremap to use it
The page cache is the most complex and important user of the radix
tree, so converting it was most important. Converting the memremap
code removes the only other user of the multiorder code, which allows
us to remove the radix tree code that supported it.
I have 40+ followup patches to convert many other users of the radix
tree over to the XArray, but I'd like to get this part in first. The
other conversions haven't been in linux-next and aren't suitable for
applying yet, but you can see them in the xarray-conv branch if you're
interested"
* 'xarray' of git://git.infradead.org/users/willy/linux-dax: (90 commits)
radix tree: Remove multiorder support
radix tree test: Convert multiorder tests to XArray
radix tree tests: Convert item_delete_rcu to XArray
radix tree tests: Convert item_kill_tree to XArray
radix tree tests: Move item_insert_order
radix tree test suite: Remove multiorder benchmarking
radix tree test suite: Remove __item_insert
memremap: Convert to XArray
xarray: Add range store functionality
xarray: Move multiorder_check to in-kernel tests
xarray: Move multiorder_shrink to kernel tests
xarray: Move multiorder account test in-kernel
radix tree test suite: Convert iteration test to XArray
radix tree test suite: Convert tag_tagged_items to XArray
radix tree: Remove radix_tree_clear_tags
radix tree: Remove radix_tree_maybe_preload_order
radix tree: Remove split/join code
radix tree: Remove radix_tree_update_node_t
page cache: Finish XArray conversion
dax: Convert page fault handlers to XArray
...
Return type of ext4_page_mkwrite and ext4_filemap_fault are
changed to use vm_fault_t type.
With this patch all the callers of block_page_mkwrite_return()
are changed to handle vm_fault_t. So converting the return type
of block_page_mkwrite_return() to vm_fault_t.
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Matthew Wilcox <willy@infradead.org>
Add new code to count canceled pending cluster reservations on bigalloc
file systems and to reduce the cluster reservation count on all file
systems using delayed allocation. This replaces old code in
ext4_da_page_release_reservations that was incorrect.
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>
maliciously crafted file systems, and some DAX fixes.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAlufGncACgkQ8vlZVpUN
gaPwuQf9FKp9yRvjBkjtnH3+s4Ps8do9r067+90y1k2DJMxKoaBUhGSW2MJJ04j+
5F6Ndp/TZHw+LfPnzsqlrAAoP3CG5+kacfJ7xeVKR0umvACm6rLMsCUct7/rFoSl
PgzCALFIJvQ9+9shuO9qrgmjJrfrlTVUgR9Mu3WUNEvMFbMjk3FMI8gi5kjjWemE
G9TDYH2lMH2sL0cWF51I2gOyNXOXrihxe+vP7j6i/rUkV+YLpKZhE1ss3Sfn6pR2
p/KjnXdupLJpgYLJne9kMrq2r8xYmDfA0S+Dec7nkox5FUOFUHssl3+q8C7cDwO9
zl6VyVFwybjFRJ/Y59wox6eqVPlIWw==
=1P1w
-----END PGP SIGNATURE-----
Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Ted writes:
Various ext4 bug fixes; primarily making ext4 more robust against
maliciously crafted file systems, and some DAX fixes.
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4, dax: set ext4_dax_aops for dax files
ext4, dax: add ext4_bmap to ext4_dax_aops
ext4: don't mark mmp buffer head dirty
ext4: show test_dummy_encryption mount option in /proc/mounts
ext4: close race between direct IO and ext4_break_layouts()
ext4: fix online resizing for bigalloc file systems with a 1k block size
ext4: fix online resize's handling of a too-small final block group
ext4: recalucate superblock checksum after updating free blocks/inodes
ext4: avoid arithemetic overflow that can trigger a BUG
ext4: avoid divide by zero fault when deleting corrupted inline directories
ext4: check to make sure the rename(2)'s destination is not freed
ext4: add nonstring annotations to ext4.h
Linus Torvalds
Theodore Ts'o
Eric Whitney
ZhangXiaoxu
Eric Biggers
yangerkun
Ross Zwisler
zhangjs
Jan Kara
Chandan Rajendra
Gabriel Krisman Bertazi
Arnd Bergmann
Jason Yan
zhangyi (F)
Andreas Dilger
Xiaoguang Wang
Nikolay Borisov
Chandan Rajendra
Vasily Averin
Matthew Wilcox
Souptick Joarder
Greg Kroah-Hartman