The size of the nilfs_type_by_mode array in the fs/nilfs2/dir.c file is
defined as "S_IFMT >> S_SHIFT", but the nilfs_set_de_type() function,
which uses this array, specifies the index to read from the array in the
same way as "(mode & S_IFMT) >> S_SHIFT".
static void nilfs_set_de_type(struct nilfs_dir_entry *de, struct inode
*inode)
{
umode_t mode = inode->i_mode;
de->file_type = nilfs_type_by_mode[(mode & S_IFMT)>>S_SHIFT]; // oob
}
However, when the index is determined this way, an out-of-bounds (OOB)
error occurs by referring to an index that is 1 larger than the array size
when the condition "mode & S_IFMT == S_IFMT" is satisfied. Therefore, a
patch to resize the nilfs_type_by_mode array should be applied to prevent
OOB errors.
Link: https://lkml.kernel.org/r/20240415182048.7144-1-konishi.ryusuke@gmail.com
Reported-by: syzbot+2e22057de05b9f3b30d8@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=2e22057de05b9f3b30d8
Fixes: 2ba466d74e ("nilfs2: directory entry operations")
Signed-off-by: Jeongjun Park <aha310510@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Fix a bug where nilfs_get_block() returns a successful status when
searching and inserting the specified block both fail inconsistently. If
this inconsistent behavior is not due to a previously fixed bug, then an
unexpected race is occurring, so return a temporary error -EAGAIN instead.
This prevents callers such as __block_write_begin_int() from requesting a
read into a buffer that is not mapped, which would cause the BUG_ON check
for the BH_Mapped flag in submit_bh_wbc() to fail.
Link: https://lkml.kernel.org/r/20240313105827.5296-3-konishi.ryusuke@gmail.com
Fixes: 1f5abe7e7d ("nilfs2: replace BUG_ON and BUG calls triggerable from ioctl")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "nilfs2: fix kernel bug at submit_bh_wbc()".
This resolves a kernel BUG reported by syzbot. Since there are two
flaws involved, I've made each one a separate patch.
The first patch alone resolves the syzbot-reported bug, but I think
both fixes should be sent to stable, so I've tagged them as such.
This patch (of 2):
Syzbot has reported a kernel bug in submit_bh_wbc() when writing file data
to a nilfs2 file system whose metadata is corrupted.
There are two flaws involved in this issue.
The first flaw is that when nilfs_get_block() locates a data block using
btree or direct mapping, if the disk address translation routine
nilfs_dat_translate() fails with internal code -ENOENT due to DAT metadata
corruption, it can be passed back to nilfs_get_block(). This causes
nilfs_get_block() to misidentify an existing block as non-existent,
causing both data block lookup and insertion to fail inconsistently.
The second flaw is that nilfs_get_block() returns a successful status in
this inconsistent state. This causes the caller __block_write_begin_int()
or others to request a read even though the buffer is not mapped,
resulting in a BUG_ON check for the BH_Mapped flag in submit_bh_wbc()
failing.
This fixes the first issue by changing the return value to code -EINVAL
when a conversion using DAT fails with code -ENOENT, avoiding the
conflicting condition that leads to the kernel bug described above. Here,
code -EINVAL indicates that metadata corruption was detected during the
block lookup, which will be properly handled as a file system error and
converted to -EIO when passing through the nilfs2 bmap layer.
Link: https://lkml.kernel.org/r/20240313105827.5296-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20240313105827.5296-2-konishi.ryusuke@gmail.com
Fixes: c3a7abf06c ("nilfs2: support contiguous lookup of blocks")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+cfed5b56649bddf80d6e@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=cfed5b56649bddf80d6e
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
All calls to nilfs_cpfile_get_checkpoint() and
nilfs_cpfile_put_checkpoint() that call kmap() and kunmap() separately are
now gone, so remove these methods.
Link: https://lkml.kernel.org/r/20240122140202.6950-15-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Move the code for reading from a checkpoint entry that is performed in
nilfs_attach_checkpoint() to the cpfile side, and make the page mapping
local and temporary. And use kmap_local instead of kmap to access the
checkpoint entry page.
In order to load the ifile inode information included in the checkpoint
entry within the inode lock section of nilfs_ifile_read(), the newly added
checkpoint reading method nilfs_cpfile_read_checkpoint() is called
indirectly via nilfs_ifile_read() instead of from
nilfs_attach_checkpoint().
Link: https://lkml.kernel.org/r/20240122140202.6950-14-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Move the checkpoint finalization routine to the cpfile side, and make the
page mapping local and temporary. And use kmap_local instead of kmap to
access the checkpoint entry page when finalizing a checkpoint.
In this conversion, some of the information on the checkpoint entry being
rewritten is passed through the arguments of the newly added method
nilfs_cpfile_finalize_checkpoint().
Link: https://lkml.kernel.org/r/20240122140202.6950-13-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In order to convert kmap() used in cpfile to kmap_local, first move the
checkpoint creation routine, which is one of the places where kmap is
used, to the cpfile side and make the page mapping local and temporary.
And use kmap_local instead of kmap to access the checkpoint entry page
(and header block page) when generating a checkpoint.
Link: https://lkml.kernel.org/r/20240122140202.6950-12-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Convert deprecated kmap() and kmap_atomic() to use kmap_local for the
ifile metadata file used to manage disk inodes.
In some usages, calls to kmap_local and kunmap_local are split into
different helpers, but those usages can be safely changed to local thread
kmap.
Link: https://lkml.kernel.org/r/20240122140202.6950-11-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
It is now clear that nilfs_bmap_write() is only used to finalize logs
written to disk. Concurrent bmap modification operations are not
performed on bmaps in this context. Additionally, this function does not
modify data used in read-only operations such as bmap lookups.
Therefore, there is no need to acquire bmap->b_sem in nilfs_bmap_write(),
so delete it.
Link: https://lkml.kernel.org/r/20240122140202.6950-10-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Before converting the disk inode management metadata file ifile, the call
to nilfs_bmap_write(), the i_device_code setting, and the zero-fill code
for inodes on the super root block are moved from
nilfs_write_inode_common() to its callers.
This cleanup simplifies the role and arguments of
nilfs_write_inode_common() and collects calls to nilfs_bmap_write() to the
log writing code.
Also, add and use a new helper nilfs_write_root_mdt_inode() to avoid code
duplication in the data export routine nilfs_segctor_fill_in_super_root()
to the super root block's buffer.
Link: https://lkml.kernel.org/r/20240122140202.6950-9-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Concerning the code of the metadata file DAT for disk address translation,
convert all parts that use the deprecated kmap_atomic to use kmap_local.
All transformations are directly possible.
Link: https://lkml.kernel.org/r/20240122140202.6950-8-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Regarding the allocator code that is commonly used in the ondisk inode
metadata file ifile and the disk address translation metadata file DAT,
convert the parts that use the deprecated kmap_atomic() and kmap() to use
kmap_local.
Most can be converted directly, but only
nilfs_palloc_prepare_alloc_entry() needs to be rewritten to change mapping
sections so that multiple kmap_local/kunmap_local calls are nested and
disk I/O can be avoided within the mapping sections.
Link: https://lkml.kernel.org/r/20240122140202.6950-7-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Concerning the code of the metadata file sufile for segment management,
convert all parts that uses the deprecated kmap_atomic() to use
kmap_local. All transformations are directly possible here.
Link: https://lkml.kernel.org/r/20240122140202.6950-6-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In the common code of metadata files, the new block creation routine
nilfs_mdt_insert_new_block() still uses the deprecated kmap_atomic(), so
convert it to use kmap_local.
Link: https://lkml.kernel.org/r/20240122140202.6950-5-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The routine nilfs_copy_buffer() that copies a block buffer still uses the
deprecated kmap_atomic(), so convert it to use kmap_local.
Link: https://lkml.kernel.org/r/20240122140202.6950-4-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In the segment buffer code used for log writing, a CRC calculation routine
uses the deprecated kmap_atomic(), so convert it to use kmap_local.
Link: https://lkml.kernel.org/r/20240122140202.6950-3-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "nilfs2: eliminate kmap and kmap_atomic calls".
This series converts remaining kmap and kmap_atomic calls to use
kmap_local, mainly in metadata files, and eliminates calls to these
deprecated kmap functions from nilfs2.
This series does not include converting metadata files to use folios, but
it is a step in that direction.
Most conversions are straightforward, but some are not: the checkpoint
file, the inode file, and the persistent object allocator. These have
been adjusted or rewritten to avoid multiple kmap_local calls or nest them
if necessary, and to eliminate long waits like block I/O within the
highmem mapping sections.
This series has been tested in both 32-bit and 64-bit environments with
varying block sizes.
This patch (of 15):
In the recovery function when mounting, nilfs_recovery_copy_block() uses
the deprecated kmap_atomic(), so convert it to use kmap_local.
Link: https://lkml.kernel.org/r/20240122140202.6950-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20240122140202.6950-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
According to a syzbot report, end_buffer_async_write(), which handles the
completion of block device writes, may detect abnormal condition of the
buffer async_write flag and cause a BUG_ON failure when using nilfs2.
Nilfs2 itself does not use end_buffer_async_write(). But, the async_write
flag is now used as a marker by commit 7f42ec3941 ("nilfs2: fix issue
with race condition of competition between segments for dirty blocks") as
a means of resolving double list insertion of dirty blocks in
nilfs_lookup_dirty_data_buffers() and nilfs_lookup_node_buffers() and the
resulting crash.
This modification is safe as long as it is used for file data and b-tree
node blocks where the page caches are independent. However, it was
irrelevant and redundant to also introduce async_write for segment summary
and super root blocks that share buffers with the backing device. This
led to the possibility that the BUG_ON check in end_buffer_async_write
would fail as described above, if independent writebacks of the backing
device occurred in parallel.
The use of async_write for segment summary buffers has already been
removed in a previous change.
Fix this issue by removing the manipulation of the async_write flag for
the remaining super root block buffer.
Link: https://lkml.kernel.org/r/20240203161645.4992-1-konishi.ryusuke@gmail.com
Fixes: 7f42ec3941 ("nilfs2: fix issue with race condition of competition between segments for dirty blocks")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+5c04210f7c7f897c1e7f@syzkaller.appspotmail.com
Closes: https://lkml.kernel.org/r/00000000000019a97c05fd42f8c8@google.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Syzbot reported a hang issue in migrate_pages_batch() called by mbind()
and nilfs_lookup_dirty_data_buffers() called in the log writer of nilfs2.
While migrate_pages_batch() locks a folio and waits for the writeback to
complete, the log writer thread that should bring the writeback to
completion picks up the folio being written back in
nilfs_lookup_dirty_data_buffers() that it calls for subsequent log
creation and was trying to lock the folio. Thus causing a deadlock.
In the first place, it is unexpected that folios/pages in the middle of
writeback will be updated and become dirty. Nilfs2 adds a checksum to
verify the validity of the log being written and uses it for recovery at
mount, so data changes during writeback are suppressed. Since this is
broken, an unclean shutdown could potentially cause recovery to fail.
Investigation revealed that the root cause is that the wait for writeback
completion in nilfs_page_mkwrite() is conditional, and if the backing
device does not require stable writes, data may be modified without
waiting.
Fix these issues by making nilfs_page_mkwrite() wait for writeback to
finish regardless of the stable write requirement of the backing device.
Link: https://lkml.kernel.org/r/20240131145657.4209-1-konishi.ryusuke@gmail.com
Fixes: 1d1d1a7672 ("mm: only enforce stable page writes if the backing device requires it")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+ee2ae68da3b22d04cd8d@syzkaller.appspotmail.com
Closes: https://lkml.kernel.org/r/00000000000047d819061004ad6c@google.com
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The helper function nilfs_recovery_copy_block() of
nilfs_recovery_dsync_blocks(), which recovers data from logs created by
data sync writes during a mount after an unclean shutdown, incorrectly
calculates the on-page offset when copying repair data to the file's page
cache. In environments where the block size is smaller than the page
size, this flaw can cause data corruption and leak uninitialized memory
bytes during the recovery process.
Fix these issues by correcting this byte offset calculation on the page.
Link: https://lkml.kernel.org/r/20240124121936.10575-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCZZ/BCAAKCRBZ7Krx/gZQ
68qqAQD6LtfYLDJGdJM+lNpyiG4BA7coYpPlJtmH7mzL+MbFPgEAnM7XsK6zyvza
3+rEggLM0UFWjg9Ln7Nlq035TeYtFwo=
=w1mD
-----END PGP SIGNATURE-----
Merge tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc filesystem updates from Al Viro:
"Misc cleanups (the part that hadn't been picked by individual fs
trees)"
* tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
apparmorfs: don't duplicate kfree_link()
orangefs: saner arguments passing in readdir guts
ocfs2_find_match(): there's no such thing as NULL or negative ->d_parent
reiserfs_add_entry(): get rid of pointless namelen checks
__ocfs2_add_entry(), ocfs2_prepare_dir_for_insert(): namelen checks
ext4_add_entry(): ->d_name.len is never 0
befs: d_obtain_alias(ERR_PTR(...)) will do the right thing
affs: d_obtain_alias(ERR_PTR(...)) will do the right thing
/proc/sys: use d_splice_alias() calling conventions to simplify failure exits
hostfs: use d_splice_alias() calling conventions to simplify failure exits
udf_fiiter_add_entry(): check for zero ->d_name.len is bogus...
udf: d_obtain_alias(ERR_PTR(...)) will do the right thing...
udf: d_splice_alias() will do the right thing on ERR_PTR() inode
nfsd: kill stale comment about simple_fill_super() requirements
bfs_add_entry(): get rid of pointless ->d_name.len checks
nilfs2: d_obtain_alias(ERR_PTR(...)) will do the right thing...
zonefs: d_splice_alias() will do the right thing on ERR_PTR() inode
many places. The notable patch series are:
- nilfs2 folio conversion from Matthew Wilcox in "nilfs2: Folio
conversions for file paths".
- Additional nilfs2 folio conversion from Ryusuke Konishi in "nilfs2:
Folio conversions for directory paths".
- IA64 remnant removal in Heiko Carstens's "Remove unused code after
IA-64 removal".
- Arnd Bergmann has enabled the -Wmissing-prototypes warning everywhere
in "Treewide: enable -Wmissing-prototypes". This had some followup
fixes:
- Nathan Chancellor has cleaned up the hexagon build in the series
"hexagon: Fix up instances of -Wmissing-prototypes".
- Nathan also addressed some s390 warnings in "s390: A couple of
fixes for -Wmissing-prototypes".
- Arnd Bergmann addresses the same warnings for MIPS in his series
"mips: address -Wmissing-prototypes warnings".
- Baoquan He has made kexec_file operate in a top-down-fitting manner
similar to kexec_load in the series "kexec_file: Load kernel at top of
system RAM if required"
- Baoquan He has also added the self-explanatory "kexec_file: print out
debugging message if required".
- Some checkstack maintenance work from Tiezhu Yang in the series
"Modify some code about checkstack".
- Douglas Anderson has disentangled the watchdog code's logging when
multiple reports are occurring simultaneously. The series is "watchdog:
Better handling of concurrent lockups".
- Yuntao Wang has contributed some maintenance work on the crash code in
"crash: Some cleanups and fixes".
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZZ2R6AAKCRDdBJ7gKXxA
juCVAP4t76qUISDOSKugB/Dn5E4Nt9wvPY9PcufnmD+xoPsgkQD+JVl4+jd9+gAV
vl6wkJDiJO5JZ3FVtBtC3DFA/xHtVgk=
=kQw+
-----END PGP SIGNATURE-----
Merge tag 'mm-nonmm-stable-2024-01-09-10-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
"Quite a lot of kexec work this time around. Many singleton patches in
many places. The notable patch series are:
- nilfs2 folio conversion from Matthew Wilcox in 'nilfs2: Folio
conversions for file paths'.
- Additional nilfs2 folio conversion from Ryusuke Konishi in 'nilfs2:
Folio conversions for directory paths'.
- IA64 remnant removal in Heiko Carstens's 'Remove unused code after
IA-64 removal'.
- Arnd Bergmann has enabled the -Wmissing-prototypes warning
everywhere in 'Treewide: enable -Wmissing-prototypes'. This had
some followup fixes:
- Nathan Chancellor has cleaned up the hexagon build in the series
'hexagon: Fix up instances of -Wmissing-prototypes'.
- Nathan also addressed some s390 warnings in 's390: A couple of
fixes for -Wmissing-prototypes'.
- Arnd Bergmann addresses the same warnings for MIPS in his series
'mips: address -Wmissing-prototypes warnings'.
- Baoquan He has made kexec_file operate in a top-down-fitting manner
similar to kexec_load in the series 'kexec_file: Load kernel at top
of system RAM if required'
- Baoquan He has also added the self-explanatory 'kexec_file: print
out debugging message if required'.
- Some checkstack maintenance work from Tiezhu Yang in the series
'Modify some code about checkstack'.
- Douglas Anderson has disentangled the watchdog code's logging when
multiple reports are occurring simultaneously. The series is
'watchdog: Better handling of concurrent lockups'.
- Yuntao Wang has contributed some maintenance work on the crash code
in 'crash: Some cleanups and fixes'"
* tag 'mm-nonmm-stable-2024-01-09-10-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (157 commits)
crash_core: fix and simplify the logic of crash_exclude_mem_range()
x86/crash: use SZ_1M macro instead of hardcoded value
x86/crash: remove the unused image parameter from prepare_elf_headers()
kdump: remove redundant DEFAULT_CRASH_KERNEL_LOW_SIZE
scripts/decode_stacktrace.sh: strip unexpected CR from lines
watchdog: if panicking and we dumped everything, don't re-enable dumping
watchdog/hardlockup: use printk_cpu_sync_get_irqsave() to serialize reporting
watchdog/softlockup: use printk_cpu_sync_get_irqsave() to serialize reporting
watchdog/hardlockup: adopt softlockup logic avoiding double-dumps
kexec_core: fix the assignment to kimage->control_page
x86/kexec: fix incorrect end address passed to kernel_ident_mapping_init()
lib/trace_readwrite.c:: replace asm-generic/io with linux/io
nilfs2: cpfile: fix some kernel-doc warnings
stacktrace: fix kernel-doc typo
scripts/checkstack.pl: fix no space expression between sp and offset
x86/kexec: fix incorrect argument passed to kexec_dprintk()
x86/kexec: use pr_err() instead of kexec_dprintk() when an error occurs
nilfs2: add missing set_freezable() for freezable kthread
kernel: relay: remove relay_file_splice_read dead code, doesn't work
docs: submit-checklist: remove all of "make namespacecheck"
...
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZZUx4wAKCRCRxhvAZXjc
osaNAQC/c+xXVfiq/pFbuK9MQLna4RGZaGcG9k312YniXbHq0AD9HAf4aPcZwPy1
/wkD4pauj3UZ3f0xBSyazGBvAXyN0Qc=
=iFAQ
-----END PGP SIGNATURE-----
Merge tag 'vfs-6.8.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs super updates from Christian Brauner:
"This contains the super work for this cycle including the long-awaited
series by Jan to make it possible to prevent writing to mounted block
devices:
- Writing to mounted devices is dangerous and can lead to filesystem
corruption as well as crashes. Furthermore syzbot comes with more
and more involved examples how to corrupt block device under a
mounted filesystem leading to kernel crashes and reports we can do
nothing about. Add tracking of writers to each block device and a
kernel cmdline argument which controls whether other writeable
opens to block devices open with BLK_OPEN_RESTRICT_WRITES flag are
allowed.
Note that this effectively only prevents modification of the
particular block device's page cache by other writers. The actual
device content can still be modified by other means - e.g. by
issuing direct scsi commands, by doing writes through devices lower
in the storage stack (e.g. in case loop devices, DM, or MD are
involved) etc. But blocking direct modifications of the block
device page cache is enough to give filesystems a chance to perform
data validation when loading data from the underlying storage and
thus prevent kernel crashes.
Syzbot can use this cmdline argument option to avoid uninteresting
crashes. Also users whose userspace setup does not need writing to
mounted block devices can set this option for hardening. We expect
that this will be interesting to quite a few workloads.
Btrfs is currently opted out of this because they still haven't
merged patches we require for this to work from three kernel
releases ago.
- Reimplement block device freezing and thawing as holder operations
on the block device.
This allows us to extend block device freezing to all devices
associated with a superblock and not just the main device. It also
allows us to remove get_active_super() and thus another function
that scans the global list of superblocks.
Freezing via additional block devices only works if the filesystem
chooses to use @fs_holder_ops for these additional devices as well.
That currently only includes ext4 and xfs.
Earlier releases switched get_tree_bdev() and mount_bdev() to use
@fs_holder_ops. The remaining nilfs2 open-coded version of
mount_bdev() has been converted to rely on @fs_holder_ops as well.
So block device freezing for the main block device will continue to
work as before.
There should be no regressions in functionality. The only special
case is btrfs where block device freezing for the main block device
never worked because sb->s_bdev isn't set. Block device freezing
for btrfs can be fixed once they can switch to @fs_holder_ops but
that can happen whenever they're ready"
* tag 'vfs-6.8.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (27 commits)
block: Fix a memory leak in bdev_open_by_dev()
super: don't bother with WARN_ON_ONCE()
super: massage wait event mechanism
ext4: Block writes to journal device
xfs: Block writes to log device
fs: Block writes to mounted block devices
btrfs: Do not restrict writes to btrfs devices
block: Add config option to not allow writing to mounted devices
block: Remove blkdev_get_by_*() functions
bcachefs: Convert to bdev_open_by_path()
fs: handle freezing from multiple devices
fs: remove dead check
nilfs2: simplify device handling
fs: streamline thaw_super_locked
ext4: simplify device handling
xfs: simplify device handling
fs: simplify setup_bdev_super() calls
blkdev: comment fs_holder_ops
porting: document block device freeze and thaw changes
fs: remove unused helper
...
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZZUxRQAKCRCRxhvAZXjc
ov/QAQDzvge3oQ9MEymmOiyzzcF+HhAXBr+9oEsYJjFc1p0TsgEA61gXjZo7F1jY
KBqd6znOZCR+Waj0kIVJRAo/ISRBqQc=
=0bRl
-----END PGP SIGNATURE-----
Merge tag 'vfs-6.8.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
"This contains the usual miscellaneous features, cleanups, and fixes
for vfs and individual fses.
Features:
- Add Jan Kara as VFS reviewer
- Show correct device and inode numbers in proc/<pid>/maps for vma
files on stacked filesystems. This is now easily doable thanks to
the backing file work from the last cycles. This comes with
selftests
Cleanups:
- Remove a redundant might_sleep() from wait_on_inode()
- Initialize pointer with NULL, not 0
- Clarify comment on access_override_creds()
- Rework and simplify eventfd_signal() and eventfd_signal_mask()
helpers
- Process aio completions in batches to avoid needless wakeups
- Completely decouple struct mnt_idmap from namespaces. We now only
keep the actual idmapping around and don't stash references to
namespaces
- Reformat maintainer entries to indicate that a given subsystem
belongs to fs/
- Simplify fput() for files that were never opened
- Get rid of various pointless file helpers
- Rename various file helpers
- Rename struct file members after SLAB_TYPESAFE_BY_RCU switch from
last cycle
- Make relatime_need_update() return bool
- Use GFP_KERNEL instead of GFP_USER when allocating superblocks
- Replace deprecated ida_simple_*() calls with their current ida_*()
counterparts
Fixes:
- Fix comments on user namespace id mapping helpers. They aren't
kernel doc comments so they shouldn't be using /**
- s/Retuns/Returns/g in various places
- Add missing parameter documentation on can_move_mount_beneath()
- Rename i_mapping->private_data to i_mapping->i_private_data
- Fix a false-positive lockdep warning in pipe_write() for watch
queues
- Improve __fget_files_rcu() code generation to improve performance
- Only notify writer that pipe resizing has finished after setting
pipe->max_usage otherwise writers are never notified that the pipe
has been resized and hang
- Fix some kernel docs in hfsplus
- s/passs/pass/g in various places
- Fix kernel docs in ntfs
- Fix kcalloc() arguments order reported by gcc 14
- Fix uninitialized value in reiserfs"
* tag 'vfs-6.8.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (36 commits)
reiserfs: fix uninit-value in comp_keys
watch_queue: fix kcalloc() arguments order
ntfs: dir.c: fix kernel-doc function parameter warnings
fs: fix doc comment typo fs tree wide
selftests/overlayfs: verify device and inode numbers in /proc/pid/maps
fs/proc: show correct device and inode numbers in /proc/pid/maps
eventfd: Remove usage of the deprecated ida_simple_xx() API
fs: super: use GFP_KERNEL instead of GFP_USER for super block allocation
fs/hfsplus: wrapper.c: fix kernel-doc warnings
fs: add Jan Kara as reviewer
fs/inode: Make relatime_need_update return bool
pipe: wakeup wr_wait after setting max_usage
file: remove __receive_fd()
file: stop exposing receive_fd_user()
fs: replace f_rcuhead with f_task_work
file: remove pointless wrapper
file: s/close_fd_get_file()/file_close_fd()/g
Improve __fget_files_rcu() code generation (and thus __fget_light())
file: massage cleanup of files that failed to open
fs/pipe: Fix lockdep false-positive in watchqueue pipe_write()
...
Correct the function parameter names for nilfs_cpfile_get_info():
cpfile.c:564: warning: Function parameter or member 'cnop' not described in 'nilfs_cpfile_get_cpinfo'
cpfile.c:564: warning: Function parameter or member 'mode' not described in 'nilfs_cpfile_get_cpinfo'
cpfile.c:564: warning: Function parameter or member 'buf' not described in 'nilfs_cpfile_get_cpinfo'
cpfile.c:564: warning: Function parameter or member 'cisz' not described in 'nilfs_cpfile_get_cpinfo'
cpfile.c:564: warning: Excess function parameter 'cno' description in 'nilfs_cpfile_get_cpinfo'
cpfile.c:564: warning: Excess function parameter 'ci' description in 'nilfs_cpfile_get_cpinfo'
Also add missing descriptions of the function's specification.
[ konishi.ryusuke@gmail.com: filled in missing descriptions ]
Link: https://lkml.kernel.org/r/20231220065931.2372-1-rdunlap@infradead.org
Link: https://lkml.kernel.org/r/20231220221342.11505-1-konishi.ryusuke@gmail.com
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The kernel thread function nilfs_segctor_thread() invokes the
try_to_freeze() in its loop. But all the kernel threads are non-freezable
by default. So if we want to make a kernel thread to be freezable, we
have to invoke set_freezable() explicitly.
Link: https://lkml.kernel.org/r/20231219090918.2329-1-konishi.ryusuke@gmail.com
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
nilfs_sufile_do_free(), which is called when log write fails or during GC,
uses WARN_ONs to check for abnormal status of metadata. In the former
case, these WARN_ONs will not be fired, but in the latter case they don't
"never-happen". It is possible to trigger these by intentionally
modifying the userland GC library to release segments that are not in the
expected state.
So, replace them with warning output using the dedicated macro
nilfs_warn().
This replaces two potentially triggered WARN_ONs with ones that use a
warning output macro.
Link: https://lkml.kernel.org/r/20231207045730.5205-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
All callers have a folio now, so convert it.
Link: https://lkml.kernel.org/r/20231127143036.2425-18-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
All callers now have a folio, so convert these two functions.
Saves one call to compound_head() in unlock_page().
[konishi.ryusuke: resolved conflicts in nilfs_{set_link,delete_entry}]
Link: https://lkml.kernel.org/r/20231127143036.2425-17-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove two calls to compound_head() and switch from kmap_atomic to
kmap_local.
Link: https://lkml.kernel.org/r/20231127143036.2425-16-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove three calls to compound_head() by using the folio API.
Link: https://lkml.kernel.org/r/20231127143036.2425-15-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove six calls to compound_head() by using the folio API.
Link: https://lkml.kernel.org/r/20231127143036.2425-14-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This involves converting nilfs_find_entry(), nilfs_dotdot(),
nilfs_set_link(), nilfs_delete_entry() and nilfs_do_unlink() to use folios
as well.
[konishi.ryusuke: followed the change of page release helper call sites]
Link: https://lkml.kernel.org/r/20231127143036.2425-13-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use the new folio APIs to remove calls to compound_head().
[konishi.ryusuke: resolved a conflict due to style warning correction]
Link: https://lkml.kernel.org/r/20231127143036.2425-12-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use the new folio APIs to remove calls to compound_head().
Link: https://lkml.kernel.org/r/20231127143036.2425-11-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Convert nilfs_get_page() to be a wrapper.
Also convert nilfs_check_page() to nilfs_check_folio().
Link: https://lkml.kernel.org/r/20231127143036.2425-10-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Match ext2 by using kmap_local() instead of kmap(). This is more
efficient. Also use unmap_and_put_page() instead of duplicating it as a
nilfs function.
[konishi.ryusuke: followed the change of page release helper call sites]
Link: https://lkml.kernel.org/r/20231127143036.2425-9-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove another use of page_address() as part of preparing for the kmap to
kmap_local transition.
Link: https://lkml.kernel.org/r/20231127143036.2425-8-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In prepartion for switching from kmap() to kmap_local(), return the kmap
address from nilfs_get_page() instead of having the caller look up
page_address().
[konishi.ryusuke: fixed a missing blank line after declaration]
Link: https://lkml.kernel.org/r/20231127143036.2425-7-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In preparation for removing kmap from directory handling, mask the
directory entry pointer to discover the start address of the page.
Matches ext2.
Link: https://lkml.kernel.org/r/20231127143036.2425-6-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In preparation for removing kmap from directory handling, use
offset_in_page() to calculate 'from'. Matches ext2.
Link: https://lkml.kernel.org/r/20231127143036.2425-5-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In preparation for removing kmap from directory handling, use
offset_in_page() to calculate 'from'. Matches ext2.
Link: https://lkml.kernel.org/r/20231127143036.2425-4-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
In nilfs_rename(), calls to nilfs_put_page() to release pages obtained
with nilfs_find_entry() or nilfs_dotdot() are alternated in the normal
path.
When replacing the kernel memory mapping method from kmap to
kmap_local_{page,folio}, this violates the constraint on the calling order
of kunmap_local().
Swap the order of nilfs_put_page calls where the kmap sections of multiple
pages overlap so that they are nested, allowing direct replacement of
nilfs_put_page() -> unmap_and_put_page().
Without this reordering, that replacement will cause a kernel WARNING in
kunmap_local_indexed() on architectures with high memory mapping.
Link: https://lkml.kernel.org/r/20231127143036.2425-3-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "nilfs2: Folio conversions for directory paths".
This series applies page->folio conversions to nilfs2 directory
operations. This reduces hidden compound_head() calls and also converts
deprecated kmap calls to kmap_local in the directory code.
Although nilfs2 does not yet support large folios, Matthew has done his
best here to include support for large folios, which will be needed for
devices with large block sizes.
This series corresponds to the second half of the original post [1], but
with two complementary patches inserted at the beginning and some
adjustments, to prevent a kmap_local constraint violation found during
testing with highmem mapping.
[1] https://lkml.kernel.org/r/20231106173903.1734114-1-willy@infradead.org
I have reviewed all changes and tested this for regular and small block
sizes, both on machines with and without highmem mapping. No issues
found.
This patch (of 17):
In a few directory operations, the call to nilfs_put_page() for a page
obtained using nilfs_find_entry() or nilfs_dotdot() is hidden in
nilfs_set_link() and nilfs_delete_entry(), making it difficult to track
page release and preventing change of its call position.
By moving nilfs_put_page() out of these functions, this makes the page
get/put correspondence clearer and makes it easier to swap
nilfs_put_page() calls (and kunmap calls within them) when modifying
multiple directory entries simultaneously in nilfs_rename().
Also, update comments for nilfs_set_link() and nilfs_delete_entry() to
reflect changes in their behavior.
To make nilfs_put_page() visible from namei.c, this moves its definition
to nilfs.h and replaces existing equivalents to use it, but the exposure
of that definition is temporary and will be removed on a later kmap ->
kmap_local conversion.
Link: https://lkml.kernel.org/r/20231127143036.2425-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20231127143036.2425-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jeongjun Park