ext4_fc_replay() stops replaying fast commit tags only when a tag
handler returns a negative error. However, ext4_fc_replay_add_range()
and ext4_fc_replay_del_range() currently return 0 from their common
exit paths even after internal failures.
This hides errors from ext4_fc_record_modified_inode(),
ext4_map_blocks(), ext4_find_extent(), ext4_ext_insert_extent(),
ext4_ext_replay_update_ex(), and ext4_ext_remove_space(). As a result,
a failed ADD_RANGE or DEL_RANGE replay can be treated as successful and
the replay code may continue with subsequent fast commit tags.
This is particularly problematic for DEL_RANGE because it may already
have marked blocks as free before ext4_ext_remove_space() fails. If the
error is swallowed, replay may continue from a partially applied range
operation.
Return the saved error from the common exit paths and make the
ERR_PTR() cases in ADD_RANGE store PTR_ERR() before jumping to out.
Fixes: 8016e29f43 ("ext4: fast commit recovery path")
Cc: stable@vger.kernel.org
Signed-off-by: Guanghui Yang <3497809730@qq.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/tencent_E3622146846A84C75C31C7D32AC4D5AD0605@qq.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
A corrupted directory can trigger the following KASAN report when
ext4_readdir() resumes from an invalid position:
BUG: KASAN: use-after-free in __ext4_check_dir_entry+0x5ef/0x820
Read of size 2 at addr ffff88810a646000 by task repro_linear/509
Call Trace:
<TASK>
dump_stack_lvl+0x53/0x70
print_report+0xd0/0x630
kasan_report+0xce/0x100
__ext4_check_dir_entry+0x5ef/0x820
ext4_readdir+0xcde/0x2b70
iterate_dir+0x1a1/0x520
__x64_sys_getdents64+0x12b/0x220
do_syscall_64+0xf9/0x540
entry_SYSCALL_64_after_hwframe+0x77/0x7f
</TASK>
KASAN reports use-after-free because the out-of-bounds access lands in an
adjacent freed page. The directory buffer itself is still referenced.
ext4_dir_llseek() invalidates the directory cookie so that ext4_readdir()
rescans directory entries from the start of the block. The rescan checks
only the lower bound of rec_len before advancing. A corrupted rec_len can
therefore place the offset where the block has insufficient space for a
complete directory entry. The rescan itself may dereference that truncated
entry, or the main loop may pass it to __ext4_check_dir_entry(). The latter
reads de->rec_len before validating the range. For example:
block offset 0 4092 4096
|---- de1.rec_len = 4092 -----|----|
de2.inode
| de2.rec_len
^ OOB, reported as UAF
de2 starts at offset 4092 in this 4 KiB block. Its four-byte inode fits in
the block, but its rec_len starts at offset 4096 and crosses the boundary.
The minimum safe length is inode-dependent. Encrypted and casefolded
directory entries need eight additional hash bytes, while a valid metadata
checksum tail is only 12 bytes.
Cache the metadata checksum feature state and derive the minimum directory
entry length from the on-disk format. Use it to bound both the rescan and
the offset passed to the main loop. Report an offset in a truncated block
tail and skip the remainder of the block, while continuing to accept an
offset exactly at the block boundary.
Reported-by: syzbot+5322c5c260eb44d209ed@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=5322c5c260eb44d209ed
Fixes: ac27a0ec11 ("[PATCH] ext4: initial copy of files from ext3")
Signed-off-by: Yao Kai <yaokai34@huawei.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20260706041313.708346-1-yaokai34@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
After implementing bitwise flags for tracking the inline data write
state in the address space fsdata parameter, the CONVERT_INLINE_DATA
state flag is left unused and can be removed.
Perform this clean-up by:
1) Deleting the CONVERT_INLINE_DATA definition from ext4.h.
2) Removing the void **fsdata argument from both the forward
declaration and the definition of the internal helper
ext4_da_convert_inline_data_to_extent().
3) Removing the void **fsdata argument from the declaration and
definition of ext4_generic_write_inline_data() and updating
the caller ext4_try_to_write_inline_data() and the internal
re-alloc retry logic accordingly.
4) Updating ext4_da_write_begin() to call
ext4_generic_write_inline_data() without the fsdata parameter.
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Aditya Prakash Srivastava <aditya.ansh182@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260703045414.1768-2-aditya.ansh182@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Instead of checking the live inode state (ext4_has_inline_data(inode)
and ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA)) in the
write_end handlers, use the fsdata parameter of the address space
operations to explicitly pass down the state in which write_begin
prepared the write.
A concurrent thread (such as ext4_page_mkwrite()) can convert the
inline data to an extent between write_begin and write_end. If this
happens, the write_end handlers would previously miss the inline
write_end path and fall through to extent-based write_end logic.
However, since block buffers were never allocated in write_begin,
this resulted in NULL pointer dereferences or data loss because
folio_buffers(folio) was NULL.
Define EXT4_WRITE_DATA_INLINE (4) as a bit flag (Bit 2), treating
fsdata as bitwise flags rather than mutually exclusive enums to keep
states of the write path independent. Communicate this state via
fsdata:
1) ext4_write_begin() and ext4_da_write_begin() set the
EXT4_WRITE_DATA_INLINE bit in *fsdata via bitwise OR when an inline
write is successfully prepared.
2) On entry, ext4_write_begin() clears the EXT4_WRITE_DATA_INLINE bit
to safely handle VFS retries (where generic_perform_write() bypasses
the fsdata initialization on its retry jump).
3) The write_end handlers perform a bitwise AND to check if the
EXT4_WRITE_DATA_INLINE bit is set and invoke the inline write_end
helper accordingly.
Furthermore, during a buffered write, ext4_write_inline_data_end()
acquires the xattr lock after preparing the write. If a concurrent
page fault (ext4_page_mkwrite()) converts the inline data to an extent
after the write_end handlers check the state but before
ext4_write_inline_data_end() acquires the xattr write lock, the
subsequent check will trigger a kernel panic via
BUG_ON(!ext4_has_inline_data(inode)).
To keep git history working and bisectability clean, replace the
BUG_ON check in ext4_write_inline_data_end() with a graceful error-
handling retry path in this same commit. If the inline data is cleared
after locking the xattr, we safely release all resources (releasing
iloc.bh, unlocking/putting the folio, stopping the active journal
transaction handle) and return 0 (VFS retry) to let the generic write
path retry the operation safely.
Reported-by: syzbot+0c89d865531d053abb2d@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=0c89d865531d053abb2d
Fixes: 3fdcfb668f ("ext4: add journalled write support for inline data")
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Aditya Prakash Srivastava <aditya.ansh182@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260703045414.1768-1-aditya.ansh182@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
When a DAX write starts before EOF but extends past i_disksize,
ext4_write_checks() skips the IOCB_NOWAIT check because
iocb->ki_pos <= old_size. However, ext4_dax_write_iter() later calls
ext4_journal_start() to prepare for inode extension, which can sleep
waiting for journal space or transaction commit.
This violates NOWAIT semantics and can stall asynchronous I/O frameworks
like io_uring that rely on non-blocking behavior.
Fix this by checking IOCB_NOWAIT before calling ext4_journal_start()
in the extending write path. If NOWAIT is set and extension is needed,
return -EAGAIN so the caller can retry in blocking context.
Example scenario:
- File: i_size = 1000, i_disksize = 1000
- DAX NOWAIT write: offset = 500, count = 2000
- ext4_write_checks(): ki_pos (500) <= old_size (1000), skip NOWAIT check
- ext4_dax_write_iter(): offset + count (2500) > i_disksize (1000)
- ext4_journal_start() → may sleep → violates NOWAIT
Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260618125735.4156639-1-libaokun@linux.alibaba.com?part=5
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Baokun Li <libaokun@linux.alibaba.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20260629113827.4074335-7-libaokun@linux.alibaba.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
file_modified() passes flags=0 which drops IOCB_NOWAIT, causing
file_update_time() to sleep in ext4_journal_start() via
ext4_dirty_inode() even in non-blocking contexts.
kiocb_modified(iocb) propagates iocb->ki_flags so that
generic_update_time() correctly returns -EAGAIN when IOCB_NOWAIT
is set and ->dirty_inode could block, matching the behavior
already adopted by XFS, FUSE, and ext2.
Affected paths:
- ext4_dio_write_checks(): DIO NOWAIT write
- ext4_write_checks(): shared by buffered (rejects NOWAIT upfront)
and DAX write (supports NOWAIT)
ext4_fallocate() in extents.c is not affected as it has no kiocb.
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Baokun Li <libaokun@linux.alibaba.com>
Link: https://patch.msgid.link/20260629113827.4074335-6-libaokun@linux.alibaba.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
For unaligned DIO writes, the previous ext4_overwrite_io() required the
entire range to fall within a single written extent. This was overly
conservative: the DIO layer only performs partial block zeroing for the
head and tail blocks when they are partially covered by the write.
Middle blocks that are fully covered are written as whole blocks
without any zeroing, so they are safe regardless of extent state.
Therefore exclusive lock is only required when partial block zeroing
will actually happen:
- The head partial block (if any) lands on a hole or unwritten extent.
- The tail partial block (if any) lands on a hole or unwritten extent.
Middle full-cover blocks can be in any state (hole, unwritten, or
written) - block allocation under shared lock is safe per the previous
patch's analysis (inode_dio_begin + i_data_sem protection).
Replace ext4_overwrite_io() with ext4_dio_needs_zeroing(), which
directly answers the question driving the lock decision. It uses at
most two ext4_map_blocks() calls: one for the head partial block (also
catching the case where it spans through the tail), and one for the
tail partial block if not already covered.
This enables shared lock for previously-rejected scenarios such as:
- Unaligned write spanning written extent + mid-range hole + written
extent at the tail.
- Unaligned write where the partial blocks land on written extents but
the middle has unwritten extents.
Performance:
Hardware: /dev/sda (rotational disk, ~1 GB/s sustained write)
Filesystem: ext4 default mkfs
Unaligned DIO writes (14336 bytes at +512 within each 16K stripe).
Each stripe is laid out as [written][unwritten][unwritten][written],
so the head and tail partial blocks land on written extents but the
middle is unwritten. Metric: IOPS.
JOBS Before After speedup
---- -------- --------- -------
1 15,547 17,381 1.12x
2 15,910 34,172 2.15x
4 15,014 57,567 3.83x
8 15,022 81,947 5.46x
16 14,586 99,126 6.80x
32 14,047 92,519 6.59x
Wall time at JOBS=32: 149.3s (Before) -> 22.7s (After), 6.58x faster.
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Baokun Li <libaokun@linux.alibaba.com>
Link: https://patch.msgid.link/20260629113827.4074335-5-libaokun@linux.alibaba.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Currently, ext4_dio_write_checks() calls ext4_overwrite_io() to
determine if a write is a pure overwrite, and upgrades to exclusive
i_rwsem if not. However, ext4_overwrite_io() uses a single
ext4_map_blocks() call which only returns the first contiguous extent of
the same type. A write spanning multiple pre-allocated extents (e.g.
written + unwritten, or two physically discontiguous written extents)
produces a false negative, forcing an unnecessary exclusive lock upgrade.
After commit 5d87c7fca2 ("ext4: avoid starting handle when dio
writing an unwritten extent") and commit 012924f0ee ("ext4: remove
useless ext4_iomap_overwrite_ops"), ext4_iomap_begin()'s fast path
accepts both EXT4_MAP_MAPPED and EXT4_MAP_UNWRITTEN without starting a
journal transaction. The iomap iteration naturally handles multi-extent
ranges: each call returns the mapping for the current segment, and
unwritten-to-written conversion is deferred to ext4_dio_write_end_io().
This means the common case of mixed written/unwritten extents never
reaches ext4_iomap_alloc() at all.
Even for the less common case where the range contains a hole and
ext4_iomap_alloc() is needed, exclusive i_rwsem is still unnecessary for
aligned non-extending writes:
- truncate/punch_hole are kept out: they require exclusive i_rwsem
(blocked by our shared lock during allocation), and inode_dio_begin()
keeps their inode_dio_wait() blocked until in-flight bios complete.
- i_data_sem write-lock inside ext4_map_blocks() serializes concurrent
extent tree modifications (parallel writers to the same hole).
- The journal handle is per-thread and does not require i_rwsem
exclusion.
- i_disksize and orphan list are not involved in non-extending writes.
Skip the ext4_overwrite_io() check entirely for aligned writes by
initializing overwrite to true and only calling ext4_overwrite_io() for
unaligned writes. Unaligned writes still need the extent state check
because concurrent partial block zeroing in the DIO layer requires
exclusive serialization unless the range is a pure written-extent
overwrite.
Performance:
Hardware: /dev/sda (rotational disk, ~1 GB/s sustained write)
Filesystem: ext4 default mkfs
Aligned 8K DIO writes spanning written+unwritten extent boundaries.
Each thread writes its own 1G region sequentially; the file is rebuilt
between runs so every block is written exactly once. Metric: IOPS.
JOBS Before After speedup
---- -------- --------- -------
1 42,322 43,329 1.02x
2 68,516 70,677 1.03x
4 62,489 97,072 1.55x
8 58,701 110,819 1.89x
16 58,569 116,392 1.99x
32 60,860 117,244 1.93x
Wall time at JOBS=32: 69.2s (Before) -> 35.4s (After), 1.96x faster.
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Baokun Li <libaokun@linux.alibaba.com>
Link: https://patch.msgid.link/20260629113827.4074335-4-libaokun@linux.alibaba.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
generic/746 started failing intermittently on ext3 (no-extent inodes).
The test triggers 'Page cache invalidation failure on direct I/O'
warnings and subsequent fsync returns -EIO. Adding a 50ms delay
between ext4_buffered_write_iter() and filemap_write_and_wait_range()
in ext4_dio_write_iter() makes the race almost always reproducible.
On no-extent inodes, DIO writes to holes cannot use unwritten extents,
so ext4_iomap_alloc() leaves m_flags=0 and ext4_map_blocks() returns 0.
The iomap layer then returns -ENOTBLK, causing fallback to buffered I/O.
The fallback path in ext4_dio_write_iter() calls
ext4_buffered_write_iter() which dirties pages, then does flush and
invalidate. However, there's an unprotected window between
ext4_buffered_write_iter() returning (with inode lock released) and
the subsequent flush+invalidate.
Concurrent async DIO completions from other threads can run
kiocb_invalidate_post_direct_write() during this window. If pages have
been re-dirtied, post-invalidation finds dirty pages and triggers the
warning, setting -EIO in the error sequence.
Consider a file with two 4k extents: [hole][written]. Thread A does
DIO to the written extent, while thread B does DIO spanning both:
kworker A (4k DIO, allocated block) kworker B (8k DIO, fallback)
----------------------------------- ----------------------------
inode_lock_shared() inode_lock_shared()
iomap_dio_rw(): iomap_dio_rw():
kiocb_invalidate_pages -> clean iomap_begin -> -ENOTBLK
submit_bio (async) dio->size = 0
inode_unlock_shared() inode_unlock_shared()
[bio pending in block layer] /* fallback: lock released */
ext4_buffered_write_iter()
inode_lock(exclusive)
generic_perform_write()
-> dirty pages [0, 8k]
inode_unlock(exclusive)
/* pages dirty, no lock */
[bio completes] filemap_write_and_wait_range()
iomap_dio_complete() -> flush dirty pages
kiocb_invalidate_post_direct_write() invalidate_mapping_pages()
invalidate_inode_pages2_range()
-> finds dirty page!
-> dio_warn_stale_pagecache()
-> errseq_set(-EIO)
This issue can be triggered through normal I/O paths, not just
intentionally overlapping DIO writes from userspace. For example,
generic/746 uses a loop device where multiple kworkers issue concurrent
I/O to the backing file. Additionally, when block_size < folio_size,
non-overlapping DIO writes that share a large folio can also trigger
the race.
Add inode_dio_wait() in ext4_buffered_write_iter() before
ext4_write_checks() to drain all in-flight DIO. This ensures that
all DIO clears existing pages before submitting IO (via
kiocb_invalidate_pages()), all BIO waits for all DIO to complete
(via inode_dio_wait()), and ext4_write_checks() observes the inode
size after all completed DIO so that ext4_block_zero_eof() does not
race with in-flight DIO, thus eliminating the race.
Fixes: 378f32bab3 ("ext4: introduce direct I/O write using iomap infrastructure")
Suggested-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/d1adcf7c-c276-458d-9cac-68a4410f7626@gmail.com
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Baokun Li <libaokun@linux.alibaba.com>
Link: https://patch.msgid.link/20260629113827.4074335-3-libaokun@linux.alibaba.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In data=journal mode, the writeback thread can hit the
WARN_ON_ONCE(sb_rdonly(sb)) in ext4_journal_check_start() while the
superblock is being remounted read-only during reboot:
Workqueue: writeback wb_workfn (flush-253:0)
RIP: 0010:ext4_journal_check_start+0x8b/0xd0
Call Trace:
__ext4_journal_start_sb+0x3c/0x1e0
mpage_prepare_extent_to_map+0x4af/0x580
ext4_do_writepages+0x3c0/0x1080
ext4_writepages+0xc8/0x1a0
do_writepages+0xc4/0x180
__writeback_single_inode+0x45/0x2f0
writeback_sb_inodes+0x26b/0x5d0
__writeback_inodes_wb+0x54/0x100
wb_writeback+0x1ac/0x320
wb_workfn+0x394/0x470
And followed by the warning:
EXT4-fs warning (device vda1): ext4_evict_inode:195: inode #6263:
comm (sd-umount): data will be lost
This issue is not reproduced every time, but frequently.
The reproduction step is to create a VM with 8 CPUs, 16G memory and
setup data=journal:
sudo tune2fs -o journal_data /dev/vda1
Run fio:
rm -f fiotest
fio --name=fiotest --rw=randwrite --bs=4k --runtime=6 --ioengine=libaio
--iodepth=256 --numjobs=8 --filename=fiotest --filesize=30G
--group_reporting
Reboot the VM, and check the console output from:
virsh console testvm
But there is no dirty inode, folio_clear_dirty_for_io clears PG_dirty
but leaves tags PAGECACHE_TAG_DIRTY and PAGECACHE_TAG_TOWRITE set which
are only cleared by __folio_start_writeback.
In data=journal mode, jbd2 checkpoints the journalled data to its final
location and clears its own dirty flag without touching folio PG_dirty
or xarray dirty flags.
The commit f4a2b42e78 ("ext4: fix stale xarray tags after writeback")
fixes when PG_dirty is still set but there is no dirty page.
Another case is PG_dirty is cleared, but PAGECACHE_TAG_DIRTY and
PAGECACHE_TAG_TOWRITE is still set. In this case, writeback thread
checks clean folio and skips it in mpage_prepare_extent_to_map:
if (!folio_test_dirty(folio) ||
...
folio_unlcok(folio);
continue
And never reaches ext4_bio_write_folio where the commit f4a2b42e78
clears the stale xarray tags. Print debug logs after the filesystem
is remounted read-only:
writepages RDONLY nrpages=2048 dirtytag=1 wbtag=0 towrite=1 sync=0
And all folios are actually clean:
folio idx=3 dirty=0 wb=0 checked=0 dirtybuf=0 jbddirty=0 mapped=1
...
We need to clear the xarray stale tags for such clean folios by
cycling them through writeback in the skip path, the same way
f4a2b42e78 does in ext4_bio_write_folio.
Fixes: dff4ac75ee ("ext4: move keep_towrite handling to ext4_bio_write_page()")
Signed-off-by: Gerald Yang <gerald.yang@canonical.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260625160127.162272-1-gerald.yang@canonical.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Syzbot/stress-ng reported an ABBA deadlock in ext4 when exercising
concurrent xattr workloads (using the ea_inode mount/format option).
The deadlock occurs between the running transaction and the eviction
thread:
- Task 1 (stress-ng): Holds a reference to a shared mbcache_entry (ce)
and calls ext4_xattr_inode_cache_find() -> ext4_iget() to retrieve
the corresponding EA inode. Since the EA inode is currently being
evicted, ext4_iget() blocks in __wait_on_freeing_inode() waiting for
eviction to complete.
- Task 2 (eviction thread): Currently evicting the same EA inode in
ext4_evict_ea_inode(). It calls mb_cache_entry_wait_unused(oe) which
blocks waiting for Task 1 to release the reference to the mbcache_entry.
To break this deadlock, implement a new ext4_iget() configuration flag
named EXT4_IGET_NOWAIT. When set, perform a non-blocking lookup of the
inode via VFS's find_inode_nowait() API.
If the inode is currently being evicted (marked with I_FREEING or
I_WILL_FREE) or created (I_CREATING), or if it is not present in the VFS
inode cache (cache miss), simply skip it (returning -ENOENT) rather than
waiting for eviction/creation to complete, breaking the ABBA cycle.
Since we return -ENOENT immediately on a cache miss, we never attempt to
allocate a new inode or call iget_locked(), completely eliminating any
TOCTOU race window.
If the returned inode is I_NEW, wait for its initialization to clear via
wait_on_new_inode(). If initialization fails and the inode is unhashed
during wait_on_new_inode() waking up (e.g., due to an I/O read error in
another thread), safely drop the reference and return -ENOENT. This
unhashed check is executed unconditionally on all cache-hit pathways to
properly handle concurrent initialization failures.
Finally, standard validation checks (including is_bad_inode,
EXT4_EA_INODE_FL, file_acl, and xattr flags) are executed as normal inside
check_igot_inode() to fully guarantee VFS-layer safety.
In ext4_xattr_inode_cache_find(), invoke ext4_iget() with the new
EXT4_IGET_NOWAIT flag to perform the non-blocking cache search.
Suggested-by: Jan Kara <jack@suse.cz>
Reported-by: Colin Ian King <colin.i.king@gmail.com>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219283
Fixes: 0a46ef2347 ("ext4: do not create EA inode under buffer lock")
Signed-off-by: Aditya Prakash Srivastava <aditya.ansh182@gmail.com>
Tested-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260626054821.1729-1-aditya.ansh182@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
An inode being evicted will never need its extra isize expanded. Set
EXT4_STATE_NO_EXPAND before ext4_mark_inode_dirty() in ext4_evict_inode()
to make this explicit and prevent any unnecessary work in
ext4_try_to_expand_extra_isize().
This also provides defense-in-depth for the s_writepages_rwsem deadlock
during mount-time orphan cleanup, ensuring the expand path is blocked
for inodes under eviction regardless of how they are reached.
Signed-off-by: Yun Zhou <yun.zhou@windriver.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260623061903.2148767-2-yun.zhou@windriver.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_try_to_expand_extra_isize() is called from __ext4_mark_inode_dirty()
while holding an active jbd2 handle. During mount (!SB_ACTIVE), the
expand path may move xattrs to external blocks and release ea_inodes via
iput(). When !SB_ACTIVE, iput() calls write_inode_now() which acquires
s_writepages_rwsem, creating a circular lock dependency:
s_writepages_rwsem --> jbd2_handle --> xattr_sem --> s_writepages_rwsem
This can be triggered via:
ext4_process_orphan() -> ext4_truncate() -> ext4_mark_inode_dirty()
-> ext4_try_to_expand_extra_isize()
or:
ext4_evict_inode() -> ext4_mark_inode_dirty()
-> ext4_try_to_expand_extra_isize()
Skip expansion when !SB_ACTIVE. This is a minor loss of functionality
(extra isize won't grow for these inodes during mount), which e2fsck
can resolve later if needed.
Reported-by: syzbot+5d19358d7eb30ffb0cc5@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=5d19358d7eb30ffb0cc5
Fixes: c8585c6fca ("ext4: fix races between changing inode journal mode and ext4_writepages")
Signed-off-by: Yun Zhou <yun.zhou@windriver.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260623061903.2148767-1-yun.zhou@windriver.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
ext4_read_inline_dir() can read a dirent header past the end of its inline
buffer, triggering a slab-out-of-bounds read during getdents64():
BUG: KASAN: slab-out-of-bounds in __ext4_check_dir_entry
Read of size 2 at addr ffff88800f3dd23c by task exploit/148
...
__ext4_check_dir_entry
ext4_read_inline_dir
iterate_dir
The dirent payload lives in a buffer of exactly inline_size bytes:
dir_buf = kmalloc(inline_size, GFP_NOFS);
but iteration runs in a position space extra_offset bytes larger
(extra_size = extra_offset + inline_size) so the synthetic "." and ".."
land at their block-dir offsets. A dirent is formed at "dir_buf + pos -
extra_offset", yet the ext4_check_dir_entry() length argument uses the
larger extra_size. A position whose dirent header would extend past
extra_size is therefore accepted, and the rescan loop's rec_len probe and
ext4_check_dir_entry() dereference de->rec_len before the entry is rejected.
Reject a position whose minimum-size dirent header would not fit within
extra_size before forming de, in both the rescan and main loops, and pass
inline_size rather than extra_size to ext4_check_dir_entry() so the length
check matches the physical buffer.
Fixes: c4d8b0235a ("ext4: fix readdir error in case inline_data+^dir_index.")
Reported-by: Weiming Shi <bestswngs@gmail.com>
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Xiang Mei <xmei5@asu.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260615190519.946736-1-xmei5@asu.edu
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Getting ext4_group_desc structure can contribute to the cost of
ext4_mb_prefetch() without any need, as most groups fail the
!EXT4_MB_GRP_TEST_AND_SET_READ check.
Optimize ext4_mb_prefetch by getting the group description only when
necessary.
The result is further increase in performance of fallocate() system call
path that triggers ext4_mb_prefetch() via a linear group scan.
Signed-off-by: Bohdan Trach <bohdan.trach@huaweicloud.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://patch.msgid.link/20260615100331.163997-3-bohdan.trach@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
EXT4_MB_GRP_TEST_AND_SET_READ uses test_and_set_bit function which
issues an atomic write. This can cause high overhead due to cache
contention when multiple threads iterate over groups in a tight loop,
as is the case for ext4_mb_prefetch(). We have seen this to be a
problem for Kunpeng 920b CPUs which uses a single ARM LSE instruction
for this purpose.
Avoid this unconditional atomic write by testing the bit first without
changing its value. This is OK for this use case as this bit is never
unset.
This change significantly reduces costs of fallocate() operations which
trigger linear group scans on large multicore machines where
test_and_set_bit issues an atomic write operation unconditionally.
Signed-off-by: Bohdan Trach <bohdan.trach@huaweicloud.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260615100331.163997-2-bohdan.trach@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Move iput(tmp_inode) after ext4_writepages_up_write() to avoid a
circular lock dependency between s_writepages_rwsem and sb_internal
(freeze protection).
The deadlock scenario:
CPU0 (EXT4_IOC_MIGRATE) CPU1 (orphan cleanup during mount)
---- ----
ext4_ext_migrate()
ext4_writepages_down_write()
s_writepages_rwsem (write)
ext4_evict_inode()
sb_start_intwrite() [sb_internal]
...
ext4_writepages()
s_writepages_rwsem (read) [BLOCKED]
iput(tmp_inode)
ext4_evict_inode()
sb_start_intwrite() [BLOCKED]
The tmp_inode is a temporary inode with nlink=0 created solely for
building the extent tree. Its eviction does not require
s_writepages_rwsem protection, so deferring iput() until after
releasing the rwsem is safe.
Reported-by: syzbot+212e8f62790f8e0bc63b@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=212e8f62790f8e0bc63b
Fixes: cb85f4d23f ("ext4: fix race between writepages and enabling EXT4_EXTENTS_FL")
Signed-off-by: Yun Zhou <yun.zhou@windriver.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20260612005330.1930804-1-yun.zhou@windriver.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Ext4 buffered writes into large folios also pay a full buffer_head
walk in ext4_block_write_begin(). For a small overwrite of an existing
cached folio, the folio is already uptodate and the write only needs to
prepare the buffers through the written range. Walking the suffix still
makes the write_begin cost proportional to the folio size.
Before ext4 enabled large folios for regular files, the same loop was
bounded by a single page of buffers. That commit made the existing
full-folio walk visible as a regression for cached small overwrites.
The suffix walk is needed for non-uptodate folios, where ext4 may have
to submit reads for partial blocks, preserve new-buffer cleanup, and run
error zeroing. Keep those folios on the old full walk.
For already-uptodate folios, keep the walk starting at the first buffer
rather than seeking directly to from. This preserves the existing prefix
buffer state handling. Stop once block_start reaches the end of the
write range, because the skipped suffix would only repeat the
outside-range uptodate handling for buffers beyond @to.
On current master, the libMicro ext4 large-folio overwrite test shows
the following full-series result. Results are median usecs/call over 10
runs, lower is better:
case nofix this series improvement
write_u1k 1.418 0.3405 76.0%
write_u10k 1.887 0.4175 77.9%
pwrite_u1k 1.6775 0.3390 79.8%
pwrite_u10k 1.9035 0.4130 78.3%
Fixes: 7ac67301e8 ("ext4: enable large folio for regular file")
Cc: stable@vger.kernel.org # v6.16+
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com>
Link: https://patch.msgid.link/20260609035202.90669-3-zhujia.zj@bytedance.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
block_commit_write() always walks every buffer_head attached to the
folio. That was cheap for order-0 folios, but large folios can contain
hundreds of buffer_heads. For a small buffered overwrite of an
already-uptodate large folio, the commit work is therefore proportional
to the folio size rather than the copied range.
This became visible with ext4 regular-file large folios, where cached
small overwrites reach block_commit_write() through block_write_end().
Before ext4 enabled large folios for regular files, this path was only
hit with order-0 folios for normal ext4 buffered writes, so the full walk
was bounded. The ext4 large-folio commit is therefore the regression
point for this generic helper cost.
The full walk is still needed when the folio is not uptodate, because
block_commit_write() uses per-buffer uptodate state to decide whether
the whole folio can be marked uptodate. Keep those folios on the old
full-buffer path.
For a folio that was already uptodate on entry, the commit no longer
needs tail buffers for folio-uptodate discovery. The copied range has
already been processed once block_start reaches @to, so stop there and
avoid the suffix walk.
Fixes: 7ac67301e8 ("ext4: enable large folio for regular file")
Suggested-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: stable@vger.kernel.org # v6.16+
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jia Zhu <zhujia.zj@bytedance.com>
Link: https://patch.msgid.link/20260609035202.90669-2-zhujia.zj@bytedance.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The mke2fs man page documents:
Valid cluster-size values are from 2048 to 256M bytes per cluster.
but EXT4_MAX_CLUSTER_LOG_SIZE was set to 30 (1GB), allowing crafted
filesystem images to specify cluster sizes up to 1GB.
On 32-bit systems with bigalloc enabled, the consistency check in
ext4_handle_clustersize():
s_blocks_per_group == s_clusters_per_group * (clustersize / blocksize)
can overflow when the cluster ratio is large enough. Since
s_blocks_per_group is not range-checked in the bigalloc path, the
wrapped product can pass the consistency check, leading to inconsistent
group geometry and potential out-of-bounds block allocation.
Reduce EXT4_MAX_CLUSTER_LOG_SIZE to 28 to match the documented 256MB
limit. With this cap, the maximum product is:
(blocksize * 8) * (256M / blocksize) = 2^31
which fits safely in a 32-bit unsigned long for all block sizes.
Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260608061112.392391-1-libaokun%40linux.alibaba.com
Signed-off-by: Baokun Li <libaokun@linux.alibaba.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://patch.msgid.link/20260608111150.827117-3-libaokun@linux.alibaba.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The TPM character devices expose a sequential command/response
interface, but their open handlers leave FMODE_PREAD and FMODE_PWRITE
enabled.
After a command leaves a response pending, pread(fd, buf, 16, 0x1400)
passes 0x1400 as *off to tpm_common_read(). The transfer length is
bounded by response_length, but the offset is used unchecked when
forming data_buffer + *off. A sufficiently large offset therefore causes
an out-of-bounds heap read through copy_to_user() and, if the copy
succeeds, an out-of-bounds zero-write through the following memset().
Positional I/O does not provide coherent semantics for this interface.
An arbitrary pread offset cannot represent how much of a response has
been consumed sequentially. The write callback always stores a command
at the start of data_buffer, while pwrite() does not update file->f_pos
and can leave the sequential read cursor stale.
Call nonseekable_open() from both open handlers. This removes
FMODE_PREAD and FMODE_PWRITE, causing positional reads and writes to
fail with -ESPIPE before reaching the TPM callbacks, and explicitly
marks the files non-seekable. Normal read() and write() continue to use
the existing sequential f_pos cursor, leaving the response state machine
unchanged.
Tested on Linux 6.12 with KASAN and a swtpm TPM2 device:
- sequential partial reads returned the complete response
- pread() and preadv() with offset 0x1400 returned -ESPIPE
- pwrite() and pwritev() with offset zero returned -ESPIPE
- the pending response remained intact after the rejected operations
- a subsequent normal command/response cycle completed normally
- no KASAN report was produced.
Fixes: 9488585b21 ("tpm: add support for partial reads")
Link: https://lore.kernel.org/all/20260710090217.191289-1-yong010301@gmail.com/
Cc: stable@vger.kernel.org
Signed-off-by: Jaewon Yang <yong010301@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull staging driver fixes from Greg KH:
"Here are some staging driver fixes for 7.2-rc3 for some reported bugs
in the vme_user and rtl8723bs drivers. These include:
- many rtl8723bs OOB fixes for when connecting to "bad" wifi hosts
- vme_user bugfixes to correctly validate some user-provided data
All of these have been in linux-next for a while with no reported
issues"
* tag 'staging-7.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: rtl8723bs: fix OOB reads in rtw_get_sec_ie(), rtw_get_wapi_ie(), and rtw_get_wps_attr()
staging: rtl8723bs: fix OOB reads in is_ap_in_tkip() IE loop
staging: rtl8723bs: fix OOB read in OnAssocRsp() IE loop
staging: rtl8723bs: fix OOB write in HT_caps_handler()
staging: rtl8723bs: fix heap buffer overflow in rtw_cfg80211_set_wpa_ie()
staging: rtl8723bs: fix OOB reads in IE loops in issue_assocreq() and join_cmd_hdl()
staging: rtl8723bs: fix OOB read in update_beacon_info() IE loop
staging: rtl8723bs: fix WEP length underflow and OOB read in OnAuth()
staging: vme_user: fix location monitor leak in tsi148 bridge
staging: vme_user: fix location monitor leak in fake bridge
staging: vme_user: bound slave read/write to the kern_buf size
staging: rtl8723bs: don't drop short TX frames in _rtw_pktfile_read()
Pull Android/IIO fixes from Greg KH:
"Here is a set of bugfixes for 7.2-rc3 that resolve a bunch of reported
issues in just the binder and iio codebases. Included in here are:
- binder driver bugfixes for both the rust and c versions for
reported problems
- lots and lots of iio driver bugfixes for lots of reported issues
(including a hid sensor driver bugfix)
Full details are in the shortlog, all of these have been in linux-next
with no reported issues"
* tag 'char-misc-7.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (36 commits)
iio: event: Fix event FIFO reset race
iio: imu: inv_icm42600: fix timestamp clock period by using lower value
iio: light: al3010: fix incorrect scale for the highest gain range
iio: adc: nxp-sar-adc: Fix the delay calculation in nxp_sar_adc_wait_for()
iio: light: tsl2591: return actual error from probe IRQ failure
iio: imu: inv_icm42600: fix timestamping by limiting FIFO reading
iio: imu: st_lsm6dsx: deselect shub page before reading whoami
rust_binder: clear freeze listener on node removal
rust_binder: reject context manager self-transaction
rust_binder: use a u64 stride when cleaning up the offsets array
binder: fix UAF in binder_free_transaction()
binder: fix UAF in binder_thread_release()
rust_binder: synchronize Rust Binder stats with freeze commands
binder: cache secctx size before release zeroes it
rust_binder: fix BINDER_GET_EXTENDED_ERROR
iio: adc: ad7779: add missing 'select IIO_TRIGGERED_BUFFER' to Kconfig
iio: adc: ad4130: add missing `select IIO_TRIGGERED_BUFFER` to Kconfig
iio: adc: ti-ads124s08: Return reset GPIO lookup errors
iio: temperature: Build mlx90635 with CONFIG_MLX90635
iio: light: al3320a: add missing REGMAP_I2C to Kconfig
...
Pull tty/serial fixes from Greg KH:
"Here are some small tty/serial/vt fixes for 7.2-rc3 that resolve some
reported problems. Included in here are:
- vt spurious modifier issue that showed up in -rc1 (reported a
bunch)
- 8250 driver bugfixes
- msm serial driver bugfix
- max310x serial driver bugfix
All of these have been in linux-next with no reported issues"
* tag 'tty-7.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: 8250: Ignore flow control on suspend/resume with no_console_suspend
serial: 8250_mid: Disable DMA for selected platforms
serial: 8250_omap: clear rx_running on zero-length DMA completes
vt: fix spurious modifier in CSI/cursor key sequences
serial: msm: Disable DMA for kernel console UART
serial: max310x: implement gpio_chip::get_direction()
Pull USB fixes from Greg KH:
"Here are a number of small USB driver fixes for many reported issues.
Included in here are:
- usb serial driver corruption and use-after-free fixes
- usb gadget rndis bugfixes for malicious/buggy host connections
- typec driver fixes for a load of different tiny reported issues
- typec mux driver revert for a broken patch in -rc1
- usb gadget driver fixes for many different reported problems
- new usb device quirks added
- usbip tool fixes and some core usbip fixes as well
- dwc3 driver fixes for minor issues
- xhci driver fixes for reported problems
- lots of other tiny usb driver fixes for many tiny issues
All of these have been in linux-next with no reported issues"
* tag 'usb-7.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (56 commits)
USB: core: ratelimit cabling message
usb: misc: usbio: fix disconnect UAF in client teardown
Revert "usb: typec: mux: avoid duplicated mux switches"
USB: chaoskey: Fix slab-use-after-free in chaoskey_release()
usb: ucsi: huawei_gaokun: move typec_altmode off stack
usb: typec: tcpci_rt1711h: unregister TCPCI port with devres
usb: typec: tcpm: Fix VDM type for Enter Mode commands
usb: typec: ucsi: cancel pending work on system suspend
usb: typec: class: drop PD lookup reference
usb: typec: ps883x: Fix DP+USB3 configuration
usb: xhci: Fix sleep in atomic context in xhci_free_streams()
xhci: sideband: fix ring sg table pages leak
usb: gadget: udc: Fix use-after-free in gadget_match_driver
usb: dwc3: run gadget disconnect from sleepable suspend context
usb: sl811-hcd: disable controller wakeup on remove
usb: typec: anx7411: use devm_pm_runtime_enable()
usb: dwc3: fix dwc3_readl() and dwc3_writel() calls in dwc3_ulpi_setup()
USB: misc: uss720: unregister parport on probe failure
usb: gadget: function: rndis: add length check for header
usb: gadget: function: rndis: add length check to response query
...
Pull s390 fixes from Vasily Gorbik:
- Fix missing array_index_nospec() call in diag310 memory topology code
to prevent speculative execution with a user controlled array index
- Fix get_align_mask() return type to match vm_unmapped_area_info
align_mask, avoiding possible truncation for future larger masks
- Remove empty zcrypt CEX2 files left over after CEX2 and CEX3 driver
removal
- Add build salt to the vDSO so it gets a unique build id, similar to
the kernel and modules
* tag 's390-7.2-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390: Add build salt to the vDSO
s390/zcrypt: Remove the empty file
s390/mm: Fix type mismatch in get_align_mask().
s390/diag: Add missing array_index_nospec() call to memtop_get_page_count()
Pull RISC-V fixes from Paul Walmsley:
"The most notable change involves the rseq kselftest common Makefile
(as it is not RISC-V-specific). The basic approach in the patch
appears similar to one used in the KVM and S390 selftests (grep for
LINUX_TOOL_ARCH_INCLUDE and SUBARCH), and the rseq kselftests pass a
quick build test on x86 after this.
- Avoid a null pointer deference in machine_kexec_prepare() that the
IMA subsystem can trigger
- Bypass libc in part of the ptrace_v_not_enabled kselftest to avoid
noise from child atfork handlers that libc might run
- Include Kconfig support for UltraRISC SoCs, already referenced by
some device drivers; and enable it in our defconfig
- Fix the build of the rseq kselftest for RISC-V by borrowing a
technique from the KVM and S390 kselftests that includes
arch-specific header files from tools/arch/<arch>/include
- Fix some memory leaks in the RISC-V vector ptrace kselftests
- Clean up some DT bindings and hwprobe documentation"
* tag 'riscv-for-linus-7.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
selftests/riscv: ptrace: Fix memory leak of regset_data in vector tests
selftests/rseq: Fix a building error for riscv arch
riscv: defconfig: enable ARCH_ULTRARISC
riscv: add UltraRISC SoC family Kconfig support
riscv: hwprobe.rst: Document EXT_ZICFISS and EXT_ZICFILP
riscv: hwprobe.rst: Make indentation consistent
dt-bindings: riscv: sort multi-letter Z extensions alphanumerically
selftests: riscv: Bypass libc in inactive vector ptrace test
riscv: Prevent NULL pointer dereference in machine_kexec_prepare()
Pull m68knommu fix from Greg Ungerer:
"Fix incorrectly updated local SoC IO access function names.
Testing didn't pick them up because there was no specific defconfig
for these particular SoC parts. New defconfigs will be introduced in
the next merge cycle to remedy that"
* tag 'm68knommu-fixes-on-top-off-7.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
m68k: coldfire: fix breakage of missed IO access updates
Pull tracing fixes from Steven Rostedt:
- Free field in error path of synthetic event parse
In __create_synth_event() the field was allocated but was not freed
in the error path
- Fix ring_buffer_event_length() on 8 byte aligned architectures
On architectures with CONFIG_HAVE_64BIT_ALIGNED_ACCESS set to y, the
ring_buffer_event_length() may return the wrong size. This is because
archs with that config set will always use the "big event meta
header" as that is 8 bytes keeping the payload 8 bytes aligned, even
when a 4 byte header could hold the size of the event
But ring_buffer_event_length() doesn't take this into account and
only subtracts 4 bytes for the meta header in the length when it
should have subtracted 8 bytes
- Have osnoise wait for a full rcu synchronization on unregister
osnoise_unregister_instance() used to call synchronize_rcu() before
freeing its copy of the instance but was switched to kfree_rcu(). The
osniose tracer has code that traverses the instances that it uses,
and inst is just a pointer to that instance. By using kfree_rcu()
instead of synchronize_rcu(), the instance that the inst pointer is
pointing to can be freed while the osnoise code is still referencing
it
That is, a rmdir on an instance first unregisters the tracer. When
the unregister finishes, the rmdir expects that the tracer is
finished with the instance that it is using. By putting back the
synchronize_rcu() in osnoise_unregister_instance() the unregistering
of osnoise will now return when all the users of the instance have
finished
- Remove an unused setting of "ret" in tracing_set_tracer()
- Fix ring_buffer_read_page() copying events
The commit that changed ring_buffer_read_page() to show dropped
events from the buffer itself, split the "commit" variable between
the commit value (with flags) and "size" that holds the size of the
sub-buffer. A cut and paste error changed the test of the reading
from checking the size of the buffer to the size of the event causing
reads to only read one event at a time
- Make tracepoint_printk a static variable
When the tracing sysctl knobs were move from sysctl.c to trace.c, the
variable tracepoint_printk no longer needed to be global. Make it
static
- Fix some typos
- Fix NULL pointer dereference in func_set_flag()
The flags update of the function tracer first checks if the value of
the flag is the same and exits if they are, and then it checks if the
current tracer is the function tracer and exits if it isn't. The
problem is that these checks need to be in a reversed order, as if
the tracer isn't the function tracer, then the flag being checked may
not exist. Reverse the order of these checks
- Fix ufs core trace events to not dereference a pointer in TP_printk()
The TP_printk() part of the TRACE_EVENT() macro is called when the
user reads the "trace" file. This can be seconds, minutes, hours,
days, weeks, and even months after the data was recorded into the
ring buffer. Thus, saving a pointer to an object into the ring buffer
and then dereferencing it from TP_printk() can cause harm as the
object the pointer is pointing to may no longer exist
Fix all the trace events in ufs core to save the device name in the
ring buffer instead of dereferencing the device descriptor from
TP_printk()
- Prevent out-of-bound reads in glob matching of trace events
The filter logic of events allows simple glob logic to add wild cards
to filter on strings. But some events have fields that may not have a
terminating 'nul' character. This may cause the glob matching to go
beyond the string. Change the logic to always pass in the length of
the field that is being matched
- Add no-rcu-check version of trace_##event##_enabled()
The trace_##event##_enabled() usually wraps trace events to do extra
work that is only needed when the trace event is enabled. But this
can hide events that are placed in locations where RCU is not
watching, and can make lockdep not see these bugs when the event is
not enabled
The trace_##event##_enabled() was updated to always test to make sure
RCU is watching to catch locations that may call events without RCU
being active
This caused a false positive for the irq_disabled() and related
events. As that use trace_irq_disabled_enabled() to force RCU to be
watching when the event is enabled via the ct_irq_enter() function,
calls the event, and then calls ct_irq_exit() to put RCU back to its
original state
The trace_irq_disabled_enabled() should not trigger a warning when
RCU is not watching because the code within its block handles the
case properly. Make a __trace_##event##_enabled() version for this
event to use that doesn't check RCU is watching as it handles the
case when it isn't
- Fix use-after-free in user_event_mm_dup()
When the enabler is removed from the link list, it is freed
immediately. But it is protected via RCU and needs to be freed after
an RCU grace period. Use queue_rcu_work() so that the event_mutex can
also be taken as user_event_put() takes the mutex on the last
reference is released
- Free type string in error path of parse_synth_field()
There's an error path in parse_synth_field() where the allocated type
string is not freed
- Add selftest that tests deferred event teardown
- Fix leak in error path of trace_remote_alloc_buffer()
If page allocation fails, the desc->nr_cpus is not incremented for
the current CPU and the allocations done for it are not freed
- Fix allocation length in trace_remote_alloc_buffer()
The logic to calculate the struct_len was doing a double count and
setting the value too large. Calculate the size upfront to fix the
error and simplify the logic
- Fix sparse CPU masks in ring_buffer_desc()
If there are sparse CPUs (gaps in the numbering), the
ring_buffer_desc() will fail as it tests the CPU number against the
number of CPUs that are used
* tag 'trace-v7.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
ring-buffer: Allow sparse CPU masks in ring_buffer_desc()
tracing/remotes: Fix struct_len in trace_remote_alloc_buffer()
tracing/remotes: Fix leak in trace_remote_alloc_buffer() error path
selftests/user_events: Wait for deferred event teardown after unregister
tracing/synthetic: Free type string on error path
tracing/user_events: Fix use-after-free in user_event_mm_dup()
tracing: Add a no-rcu-check version of trace_##event##_enabled()
tracing: Prevent out-of-bounds read in glob matching
ufs: core: tracing: Do not dereference pointers in TP_printk()
tracing: Fix NULL pointer dereference in func_set_flag()
samples: ftrace: Fix typos in benchmark comment
tracing: Make tracepoint_printk static as not exported
ring-buffer: Fix ring_buffer_read_page() copying only one event per page
tracing: Remove unused ret assignment in tracing_set_tracer()
tracing/osnoise: Call synchronize_rcu() when unregistering
ring-buffer: Fix event length with forced 8-byte alignment
tracing/synthetic: Free pending field on error path
Pull input fixes from Dmitry Torokhov:
- fix MELFAS MMS114 touchscreen driver to reject invalid touch IDs and
avoid multi-touch slot corruption
- fix a crash in the Sega Dreamcast (Maple) mouse driver when opening
the device, caused by missing driver data
- fixes for Maple drivers (keyboard, mouse, joystick) to properly order
setting driver data and device registration to avoid races
* tag 'input-for-v7.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: mms114 - fix multi-touch slot corruption
Input: maple_keyb - set driver data before registering input device
Input: maplecontrol - set driver data before registering input device
Input: maplemouse - set driver data before registering input device
Input: maplemouse - fix NULL pointer dereference in open()
Pull device mapper fixes from Mikulas Patocka:
- dm-log: fix overflow on 32-bit machines
- dm-era: fix out of bounds memory access; fix crashes on invalid args
- dm-verity: fix buffer overflow in forward error correction
- dm-thin: fix misbehavior on I/O failures
- dm-pcache: fix NULL pointer dereference on invalid arguments
- dm-inlinecrypt: fix memory leak on error handling
- dm-integrity: fix ignoring the 'fix_hmac' option on device open
- dm: don't store the keyring in memory for a long term
- 12 miscellaneous fixes for bugs found by Claude Opus 4.6
* tag 'for-7.2/dm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (23 commits)
dm thin metadata: fix superblock refcount leak on snapshot shadow failure
dm-stats: fix dm_jiffies_to_msec64
dm-stats: fix merge accounting
dm-bufio: fix wrong count calculation in dm_bufio_issue_discard
dm-verity: make error counter atomic
dm-verity: increase sprintf buffer size
dm-verity: fix a possible NULL pointer dereference
dm-verity: avoid double increment of &use_bh_wq_enabled
dm-ioctl: fix a possible overflow in list_version_get_info
dm_early_create: fix freeing used table on dm_resume failure
dm-integrity: fix a bug if the bio is out of limits
dm-integrity: don't increment hash_offset twice
dm-integrity: fix leaking uninitialized kernel memory
dm-integrity: fix the 'fix_hmac' option
dm era: fix error code propagation in era_ctr()
dm era: fix NULL pointer dereference in metadata_open()
dm: avoid leaking the caller's thread keyring via the table device file
dm-inlinecrypt: Fix an error handling path in inlinecrypt_ctr()
dm-pcache: reject option groups without values
dm thin metadata: fix metadata snapshot consistency on commit failure
...
Pull perf events fixes from Ingo Molnar:
- Fix SVM #GP on AMD CPUs that LBR but not BRS (Sandipan Das)
- Fix UAF bug in the perf AUX code (Lee Jia Jie)
- Fix address leakage in the AMD LBR code (Sandipan Das)
- Fix address leakage in the AMD BRS code (Sandipan Das)
* tag 'perf-urgent-2026-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/amd/brs: Fix kernel address leakage
perf/x86/amd/lbr: Fix kernel address leakage
perf/aux: Fix page UAF in map_range()
perf/x86/amd/core: Avoid enabling BRS from the SVM reload path
Pull x86 fixes from Ingo Molnar:
- Fix resctrl resource leak (Tony Luck)
- Fix resctrl umount race (Tony Luck)
- Fix resctrl double-free (Reinette Chatre)
- Fix x86 VGA display fallback logic during bootup on
certain multi-GPU systems (Mario Limonciello)
- Re-add a WBINVD call to the SNP bootstrap path to
fix an SNP regression (Tycho Andersen)
* tag 'x86-urgent-2026-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/virt/sev: Revert "Drop WBINVD before setting MSR_AMD64_SYSCFG_SNP_EN"
x86/video: Only fall back to vga_default_device() without screen info
fs/resctrl: Fix double-add of pseudo-locked region's RMID to free list
fs/resctrl: Fix use-after-free during unmount
fs/resctrl: Free mon_data structures on rdt_get_tree() failure
Pull timer fix from Ingo Molnar:
- Fix a subtle posix-cpu-timers vs. exec() race, which
unearthed other races in the area (Thomas Gleixner)
* tag 'timers-urgent-2026-07-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
posix-cpu-timers: Prevent UAF caused by non-leader exec() race
Pull block fixes from Jens Axboe:
- Limit blk_hctx_poll() to one jiffy. Prevents buggy drivers from
spinning for too long, hence triggering a stalled RCU read section
warning
- Avoid a potential deadlock on zone revalidation failure, which could
otherwise trigger a lockdep circular locking splat during a SCSI disk
rescan
- Remove a redundant GD_NEED_PART_SCAN set in add_disk_final()
- Make writes to queue/wbt_lat_usec honor the WBT enable state
- ublk fix to snapshot the batch commands before preparing IO, so that
userspace can't change an already processed tag and trip the
WARN_ON_ONCE() in the rollback path
- xen-blkfront fix for a double completion of split requests on resume
- drbd fix to reject data replies with an out-of-range payload size
* tag 'block-7.2-20260710' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
block: remove redundant GD_NEED_PART_SCAN in add_disk_final()
drbd: reject data replies with an out-of-range payload size
xen-blkfront: fix double completion of split requests on resume
ublk: snapshot batch commands before preparing I/O
block: Make WBT latency writes honor enable state
block: avoid potential deadlock on zone revalidation failure
blk-mq: bound blk_hctx_poll() to one jiffy
Pull io_uring fixes from Jens Axboe:
- Restore full RCU read section in io_req_local_work_add(), which was
mistakenly dropped with the DEFER_TASKRUN rework in this merge
window. Revert the commit that grabbed the RCU read lock in
io_ctx_mark_taskrun(), as that's no longer required with the previous
fix.
- Fix a dangling iovec after a provided-buffer bundle grow failure,
also an issue introduced in this merge window.
- Reject IORING_CQE_F_32 flag pass-through in MSG_RING to rings that
weren't setup with CQE32 or CQE_MIXED.
- Return -EINVAL rather than -ENOMEM from get_unmapped_area() when mmap
validation fails, matching io_uring_mmap().
* tag 'io_uring-7.2-20260710' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
Revert "io_uring: grab RCU read lock marking task run"
io_uring: restore RCU read section in io_req_local_work_add()
io_uring: fix dangling iovec after provided-buffer bundle grow failure
io_uring/uring_cmd: fix uring_cmd.c comments
io_uring/msg_ring: reject CQE32 flag pass-through to normal rings
io_uring/memmap: return -EINVAL from get_unmapped_area() on bad mmap
__reserve_metadata_snap() increments THIN_SUPERBLOCK_LOCATION in the
metadata space map before shadowing it. When dm_tm_shadow_block()
fails, a reference is leaked in the metadata space map.
Fix by adding the missing dm_sm_dec_block().
Signed-off-by: Genjian Zhang <zhanggenjian@kylinos.cn>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: cc8394d86f ("dm thin: provide userspace access to pool metadata")
Cc: stable@vger.kernel.org
A user-only branch stack can contain branches that originate from
the kernel. As a result, kernel addresses are exposed to user space
even when PERF_SAMPLE_BRANCH_USER is requested. On AMD processors
supporting X86_FEATURE_BRS (Zen 3 only), perf can still report entries
such as SYSRET/interrupt returns for which the branch-from addresses
are in the kernel.
E.g.
$ perf record -j any,u -c 4000 -e branch-brs -o - -- \
perf bench syscall basic --loop 1000 | \
perf script -i - -F brstack|tr ' ' '\n'| \
grep -E '0x[89a-f][0-9a-f]{15}'
...
0xffffffff810001c4/0x72e2e32955eb/-/-/-/0//-
0xffffffff810001c4/0x72e2d94a9821/-/-/-/0//-
0xffffffff810001c4/0x72e2d94ffa1b/-/-/-/0//-
...
BRS provides no hardware branch filtering, so privilege level
filtering is performed entirely in software. However, amd_brs_match_plm()
only validates the branch-to address against the requested privilege
levels. For branches from the kernel to user space, the branch-from
address is left unchecked and is leaked. Extend the software filter to
also validate the branch-from address, so that any branch record whose
branch-from address is in the kernel is dropped when
PERF_SAMPLE_BRANCH_USER is requested.
Fixes: 8910075d61 ("perf/x86/amd: Enable branch sampling priv level filtering")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: stable@vger.kernel.org
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://patch.msgid.link/f05931c4f89a146c364bd5dc6b8170b1ac611c65.1783701239.git.sandipan.das@amd.com
Closes: https://lore.kernel.org/all/20260710110235.F3FD81F000E9@smtp.kernel.org/
If the touchscreen controller reports a touch ID of 0, the driver
calculates the slot ID as touch->id - 1, which underflows to UINT_MAX.
This is passed to input_mt_slot() as -1.
Since the input core ignores negative slot values, the active slot remains
unchanged. The driver then reports the touch coordinates for the previously
active slot, corrupting its state.
Fix this by rejecting touch reports with ID 0.
Fixes: 07b8481d4a ("Input: add MELFAS mms114 touchscreen driver")
Cc: stable@vger.kernel.org
Reported-by: sashiko-bot@kernel.org
Assisted-by: Antigravity:gemini-3.5-flash
Link: https://patch.msgid.link/20260704060115.353049-1-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Pull regulator fixes from Mark Brown:
"A couple of straightforward fixes for device loading, plus a fix for
the core support for keeping multiple regulators with voltages close
to each other that was sadly introduced due to one of the more
beautiful corners of our API design"
* tag 'regulator-fix-v7.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator:
regulator: core: regulator_lock_two() should test for EDEADLK not EDEADLOCK
regulator: mt6363: add missing MODULE_DEVICE_TABLE()
regulator: mt6316: add missing MODULE_DEVICE_TABLE()
Pull audit fixes from Paul Moore:
"Two relatively small audit patches to fix potential data races with
the main audit backlog queue as well as possible integer overflows
when logging data as hex strings"
* tag 'audit-pr-20260710' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: fix potential integer overflow in audit_log_n_hex()
audit: Fix data races of skb_queue_len() readers on audit_queue
Pull selinux fixes from Paul Moore:
"Two small SELinux patches to fix a missing permission check for TCP
Fast Open operations and fix a socket lookup issue with SCTP ASCONF
operations"
* tag 'selinux-pr-20260710' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: avoid sk_socket dereference in selinux_sctp_bind_connect()
selinux: check connect-related permissions on TCP Fast Open
Pull ntfs fixes from Namjae Jeon:
- fix stale runlist element dereferences in MFT writeback and fallocate
- fix mrec_lock ABBA deadlock in rename
- prevent userspace modification of NTFS system files
- avoid inode eviction/writeback self-deadlocks
- reject malformed resident attributes in non-resident runlist mapping
- avoid post_write_mst_fixup() on invalid index blocks
- fix a hole runlist leak in insert-range error handling
- sanitize directory lookup MFT references from disk
- fail attribute-list updates after SB_ACTIVE is cleared during
teardown
* tag 'ntfs-for-7.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/ntfs:
ntfs: fail attrlist updates when the superblock is inactive
ntfs: sanitize MFT references returned from ntfs_lookup_inode_by_name()
ntfs: fix hole runlist memory leak in insert range error path
ntfs: avoid calling post_write_mst_fixup() for invalid index_block
ntfs: fix WARN_ON for resident attribute in ntfs_map_runlist_nolock()
ntfs: avoid self-deadlock during inode eviction
ntfs: make system files immutable to prevent corruption
ntfs: fix mrec_lock ABBA deadlock in rename
ntfs: avoid stale runlist element dereference in fallocate
ntfs: avoid stale runlist element dereference in MFT writeback
Pull NFS client fixes from Anna Schumaker:
- SUNRPC:
- Release lower rpc_clnt if killed waiting for XPRT_LOCKED
- Pin upper rpc_clnt across the TLS connect_worker
- NFS:
- Include MAY_WRITE in open permission mask for O_TRUNC
- Charge unstable writes by request size, not folio size
* tag 'nfs-for-7.2-2' of git://git.linux-nfs.org/projects/anna/linux-nfs:
NFS: Charge unstable writes by request size, not folio size
NFSv4: include MAY_WRITE in open permission mask for O_TRUNC
SUNRPC: pin upper rpc_clnt across the TLS connect_worker
SUNRPC: release lower rpc_clnt if killed waiting for XPRT_LOCKED
