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1,481,701 commits

Author SHA1 Message Date
Zhi Li
7c27c1b7b3 dt-bindings: ethernet: eswin: relax internal delay model to range-based constraints
Relax internal delay constraints for EIC7700 Ethernet binding.

Replace fixed enumeration of rx-internal-delay-ps and tx-internal-delay-ps
with a range-based definition (0-2540 ps, 20 ps steps) to reflect actual
hardware capability.

Mark rx/tx internal delay properties as optional, as they are board-
specific tuning parameters rather than mandatory configuration.

Update the device tree example to align with the relaxed constraint model
and remove delay properties from the example to avoid implying they are
required.

No functional change to existing DT users.

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Zhi Li <lizhi2@eswincomputing.com>
Link: https://patch.msgid.link/20260707064131.1282-1-lizhi2@eswincomputing.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-07-21 09:06:02 +02:00
Marek Szyprowski
020e209272 riscv: defconfig: thead: enable PCA953X GPIO driver
Enable PCA953X GPIO driver to properly probe Wifi pwrseq driver on
LicheePi4a board.

Reviewed-by: Drew Fustini <fustini@kernel.org>
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Drew Fustini <fustini@kernel.org>
2026-07-20 22:05:33 -07:00
Mykola Lysenko
c4c0673e4c btrfs: raid56: fix scrub read assembly submitting no reads
Commit 5387bd9581 ("btrfs: raid56: remove sector_ptr structure")
converted the bio-list membership checks from sector pointers to
physical addresses. The two conversions in rmw_assemble_write_bios()
kept their polarity (skip the sector when it is NOT in the bio list,
i.e. when there is nothing to write), but scrub_assemble_read_bios()
has the opposite polarity -- skip the sector when it IS in the bio
list, because then there is nothing to read -- and the conversion
flipped it:

	-	sector = sector_in_rbio(rbio, stripe, sectornr, 1);
	-	if (sector)
	+	paddr = sector_paddr_in_rbio(rbio, stripe, sectornr, 1);
	+	if (paddr == INVALID_PADDR)
		continue;

Since a parity-scrub rbio's bio list only holds the empty completion
bio, the result is that scrub_assemble_read_bios() submits no reads at
all. finish_parity_scrub() then compares the parity it computes from
the (cached, correct) data stripes against whatever happens to be in
the freshly allocated, uninitialized stripe pages:

  - if the garbage differs from the computed parity, the sector is
    "repaired" and written back -- accidentally producing the correct
    on-disk result;

  - if a recycled page happens to still hold the old (correct) parity
    content, the sector is deemed clean, dropped from dbitmap, and the
    actually-corrupt on-disk parity is left in place. (Scrub reports
    no errors either way: there is no counter for P/Q corruption by
    design, so the bug here is purely the failure to read and repair.)

The second case is intermittent because it depends on page-allocator
recycling. Observed with fstests btrfs/297 (raid5, 2 devices): the
corrupted P stripe intermittently stays corrupt after a scrub --
roughly 1/10 runs on x86-64 KVM and up to 7/8 on a UML build whose
timing favors page reuse.

Since the bio-list check can never be true for a parity-scrub rbio --
raid56_parity_alloc_scrub_rbio() adds a single empty completion bio
(asserting bi_size == 0), bio_paddrs[] is only populated by
index_rbio_pages() which is never called for BTRFS_RBIO_PARITY_SCRUB,
and rbio_can_merge() refuses to merge rbios of different operations --
remove the dead check entirely and assert the invariant instead, as
suggested by Qu Wenruo.

After this fix the injected corruption is read, detected and repaired
in every run (8/8 UML, 10/10 KVM), and the new assertion never fires
across the full fstests raid group.

Fixes: 5387bd9581 ("btrfs: raid56: remove sector_ptr structure")
CC: stable@vger.kernel.org # 7.1+
Suggested-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Assisted-by: Claude:claude-fable-5
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Mykola Lysenko <nickolay.lysenko@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-21 06:44:08 +02:00
Johannes Thumshirn
ab602da96a btrfs: zoned: skip fully truncated ordered extents at zone finish
A fully truncated ordered extent (truncated_len == 0) wrote no data, so its
->csum_list is empty and btrfs_finish_ordered_zoned() trips:

  assertion failed: !list_empty(&ordered->csum_list), in fs/btrfs/zoned.c:2141

Since commit 66ff4d366e a short or cancelled direct IO write finishes the
unsubmitted ordered extent as truncated with uptodate = true instead of
setting BTRFS_ORDERED_IOERR, so it now reaches btrfs_finish_ordered_zoned()
rather than being skipped by the IOERR check in btrfs_finish_ordered_io().
generic/208 hits this on a zoned filesystem.

Return early for these, like the BTRFS_ORDERED_PREALLOC case; there is no
zone append result to record and btrfs_finish_one_ordered() skips them too.

Fixes: 66ff4d366e ("btrfs: fix false IO failure after falling back to buffered write")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-21 06:43:46 +02:00
Paul E. McKenney
0d214d14be btrfs: initialize 'args' to avoid compiler warning in btrfs_ioctl_get_csums()
[COMPILER WARNING]
With GCC 11.5.0 and KASAN enabled on ARM, the following warning is
triggered during compiling:

  In file included from ./include/asm-generic/rwonce.h:26,
		   from ./arch/arm64/include/asm/rwonce.h:81,
		   from ./include/linux/compiler.h:369,
		   from ./include/linux/array_size.h:5,
		   from ./include/linux/kernel.h:16,
		   from fs/btrfs/ioctl.c:6:
  In function ‘instrument_copy_from_user_before’,
      inlined from ‘_inline_copy_from_user’ at ./include/linux/uaccess.h:184:2,
      inlined from ‘copy_from_user’ at ./include/linux/uaccess.h:222:9,
      inlined from ‘btrfs_ioctl_get_csums.isra’ at fs/btrfs/ioctl.c:5220:6:
  ./include/linux/kasan-checks.h:38:27: warning: ‘args’ may be used uninitialized [-Wmaybe-uninitialized]
     38 | #define kasan_check_write __kasan_check_write
  ./include/linux/instrumented.h:146:9: note: in expansion of macro ‘kasan_check_write’
    146 |         kasan_check_write(to, n);
	|         ^~~~~~~~~~~~~~~~~
  fs/btrfs/ioctl.c: In function ‘btrfs_ioctl_get_csums.isra’:
  ./include/linux/kasan-checks.h:20:6: note: by argument 1 of type ‘const volatile void *’ to ‘__kasan_check_write’ declared here
     20 | bool __kasan_check_write(const volatile void *p, unsigned int size);
	|      ^~~~~~~~~~~~~~~~~~~
  fs/btrfs/ioctl.c:5201:43: note: ‘args’ declared here
   5201 |         struct btrfs_ioctl_get_csums_args args;
       |                                           ^~~~

[POSSIBLE FALSE ALERTS]
This seems to be a false alert from certain GCC versions.

The @args is immediately over-written by copy_from_user(), and there is
no code touching that @args until copy_from_user() finished correctly.

[WORKAROUND]
Initialize 'args' to zero, which suppresses the warning.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-21 06:43:15 +02:00
Guanghui Yang
8bc4d72096 btrfs: zoned: fix missing chunk metadata reservation
reserve_chunk_space() stores the return value of
btrfs_zoned_activate_one_bg() in ret. The helper can return 1 after
successfully activating a block group, but ret is later used to decide
whether to reserve metadata for chunk tree updates.

As a result, successful activation skips btrfs_block_rsv_add() and leaves
trans->chunk_bytes_reserved unchanged. Use a separate variable for the
activation result so positive success does not affect the later
reservation. Keep activation failures in ret instead of returning early so
the function uses the common tail path.

Fixes: b6a98021e4 ("btrfs: zoned: activate necessary block group")
CC: stable@vger.kernel.org
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Guanghui Yang <3497809730@qq.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-21 06:42:40 +02:00
Qu Wenruo
330dcc553f btrfs: raid56: fix an incorrect csum skip during scrub
Commit 7425a28940 ("btrfs: introduce btrfs_bio_for_each_block_all()
helper") uses the new helper to replace the nested loop inside
verify_bio_data_sectors(), which simplifies the code.

However that also changed the behavior of "continue" when a block has no
data checksum.

Previously the "continue" would skip the old for() loop, which would also
increase @total_sector_nr.

Now the "continue" will skip the new btrfs_bio_for_each_block_all()
loop, which doesn't update @total_sector_nr.

This means if we hit a block that has no data checksum, we will skip all
the remaining blocks no matter if they have data checksum.
As @total_sector_nr will never be updated, and that test_bit() will
always return false.

Fix it by increasing @total_sector_nr before calling "continue".

Fixes: 7425a28940 ("btrfs: introduce btrfs_bio_for_each_block_all() helper")
Reviewed-by: Daniel Vacek <neelx@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-21 06:41:18 +02:00
Dongjiang Zhu
c438d34ec1 btrfs: report missing raid stripe tree root during lookup
When rescue=ibadroots ignores a failure to load the raid stripe tree root,
fs_info->stripe_root remains NULL. After the rescue mount proceeds, reading
file data that requires the raid stripe tree reaches
btrfs_get_raid_extent_offset().

Currently btrfs_search_slot() handles the NULL root and returns -EINVAL.
This avoids a NULL pointer dereference, but provides no diagnostic and
incorrectly describes missing filesystem metadata as an invalid argument.

Check stripe_root before allocating a path, emit a rate-limited error with
the logical address, and return -EUCLEAN.

Lookups with a valid stripe root are unchanged.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Dongjiang Zhu <zhudongjiang@fnnas.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-21 06:41:11 +02:00
Dongjiang Zhu
51a0e83998 btrfs: skip global block reserve accounting for rescue mounts
[BUG]
Mounting with rescue=ibadroots after corrupting the block group tree
root triggers a NULL pointer dereference:

  BUG: kernel NULL pointer dereference, address: 0000000000000100
  RIP: 0010:btrfs_update_global_block_rsv+0x9d/0x1c0 [btrfs]
  Call Trace:
   fill_dummy_bgs+0xd4/0x120 [btrfs]
   open_ctree+0xc6e/0x1ca0 [btrfs]
   btrfs_get_tree+0x50d/0xa40 [btrfs]

The same crash occurs with a corrupted raid stripe tree root, via
btrfs_read_block_groups() instead of fill_dummy_bgs().

[CAUSE]
With rescue=ibadroots, btrfs_read_roots() allows the mount to continue
when either root cannot be read, leaving the corresponding root pointer
NULL while its on-disk feature bit remains set.

btrfs_update_global_block_rsv() then dereferences the missing root based
on the feature bit alone.

[FIX]
Rescue mounts are fully read-only and cannot start transactions, so the
global reserve is never consumed. Under btrfs_is_full_ro(), mark the
reserve as full and return before performing the accounting.

And since we need to check if the fs is mount fully RO, export
fs_is_full_ro() as btrfs_is_full_ro(), and move it to fs.h.

Fixes: 8dbfc14fc7 ("btrfs: account block group tree when calculating global reserve size")
Fixes: 515020900d ("btrfs: read raid stripe tree from disk")
Suggested-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Dongjiang Zhu <zhudongjiang@fnnas.com>
[ Squash the fs_is_full_ro() export commit into this one. ]
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-21 06:40:18 +02:00
Johannes Thumshirn
5fabb1cf25 btrfs: zoned: reset meta_write_pointer on zone reset
btrfs_reset_unused_block_groups() resets a block group's zone and sets
alloc_offset back to 0 so the space can be reused, but it leaves
meta_write_pointer pointing at the previous end of the zone.

Once the block group is reactivated and reused for metadata, newly
allocated tree blocks live before that stale write pointer.
btrfs_check_meta_write_pointer() then sees them behind the write pointer,
so they can never be written out in sequential order: the dirty extent
buffers are stranded and pin their btree_inode folios until unmount.

Reset meta_write_pointer back to the start of the block group for
metadata and system block groups.

Fixes: 453a73c306 ("btrfs: zoned: reclaim unused zone by zone resetting")
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-21 06:40:07 +02:00
Johannes Thumshirn
1ebe51c29f btrfs: zoned: fix deadlock between metadata writeback and transaction commit
When writing out metadata extent buffers in a zoned filesystem,
btree_writepages() holds fs_info->zoned_meta_io_lock across the whole
writeback loop, including the call to btrfs_check_meta_write_pointer() ->
check_bg_is_active().

For the tree-log block group, check_bg_is_active() may fail to activate
the zone and fall back to btrfs_zone_finish_one_bg() to free an active
zone. That path waits for the running transaction to commit while still
holding zoned_meta_io_lock, but the committer needs that same lock to
write out the tree extents, so the two tasks deadlock:

  Task A (kworker, metadata writeback)      Task B (fsstress, transaction commit)
  ------------------------------------      -------------------------------------
  wb_workfn()                               btrfs_commit_transaction(T)
   btree_writepages()                        btrfs_write_and_wait_transaction()
    btrfs_zoned_meta_io_lock()                btrfs_write_marked_extents()
    btrfs_check_meta_write_pointer()           btree_writepages()
     check_bg_is_active() [treelog_bg]          btrfs_zoned_meta_io_lock()
      btrfs_zone_finish_one_bg()               <blocks on zoned_meta_io_lock,
       btrfs_zone_finish()                      held by Task A>
        do_zone_finish()
         btrfs_inc_block_group_ro()
          btrfs_wait_for_commit()
           <blocks waiting for commit
            of transaction T, done by
            Task B>

The sibling branch in check_bg_is_active() already drops zoned_meta_io_lock
around do_zone_finish() for this exact reason. Do the same in the tree-log
branch: release the lock around btrfs_zone_finish_one_bg() and re-acquire
it afterwards. The lock only protects fs_info->active_{meta,system}_bg,
which this branch does not touch, and ctx->zoned_bg keeps a reference to
the block group across the unlock, so nothing is lost while the lock
is dropped.

This hang occasionally reproduces with fstests generic/475 on a zoned
btrfs filesystem.

Fixes: 13bb483d32 ("btrfs: zoned: activate metadata block group on write time")
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-21 06:39:54 +02:00
Qu Wenruo
6881f45d0e btrfs: fix leaking BTRFS_FS_STATE_REMOUNTING flag
[BUG]
The following script can lead to unexpected qgroup rescan failure:

  # mkfs.btrfs -f -O quota $dev
  # mount $dev $mnt
  # mount -o remount,rescue=ibadroots $mnt
    ^^^^^ This above command is expected to fail

  # btrfs quota rescan -w $mnt
    ^^^^^ The above qgroup rescan is not expected to fail

  # btrfs qgroup show $mnt
  WARNING: qgroup data inconsistent, rescan recommended
  Qgroupid    Referenced    Exclusive   Path
  --------    ----------    ---------   ----
  0/5           16.00KiB     16.00KiB   <toplevel>

The above short script will be converted to a proper fstests case.

[CAUSE]
Inside btrfs_reconfigure(), if either btrfs_check_options() or
btrfs_check_features() failed, we will always have
BTRFS_FS_STATE_REMOUNTING set for the fs until the next successful
remount.

That BTRFS_FS_STATE_REMOUNTING flag will interrupt several operations,
including:

- Qgroup rescan
- Auto defrag
- Space reclaim

[FIX]
Change the error handling of btrfs_check_options() and
btrfs_check_features() to goto restore label.

Fixes: eddb1a433f ("btrfs: add reconfigure callback for fs_context")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-21 06:39:39 +02:00
Xu Rao
b27e195d4d cdrom: fix stack out-of-bounds read in CDROMVOLCTRL
mmc_ioctl_cdrom_volume() first reads the audio control mode page into a
32-byte stack buffer with cgc->buflen set to 24.  If the device reports a
block descriptor, the function increases cgc->buflen to include that
descriptor and reads the page again.

For CDROMVOLCTRL, the function then builds a MODE SELECT parameter list
by moving cgc->buffer forward by offset - 8 bytes.  This drops the block
descriptor from the outgoing payload and leaves a new 8-byte mode
parameter header in front of the audio control page.  However, cgc->buflen
is left unchanged.

With a standard 8-byte block descriptor, cgc->buffer points at buffer + 8
but cgc->buflen remains 32.  cdrom_mode_select() therefore asks the low
level packet path to write 32 bytes from that adjusted pointer, reading 8
bytes past the end of the 32-byte stack buffer.

This is not hit by CDROMVOLREAD, and CDROMVOLCTRL only triggers it on
drives that return a non-zero block descriptor length, which helps explain
why it has gone unnoticed.  The overread is also sent to the device as
extra MODE SELECT payload, so it may not produce an obvious local failure.

Reduce cgc->buflen by the same amount as the buffer pointer adjustment so
the MODE SELECT transfer covers only the intended parameter list.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Xu Rao <raoxu@uniontech.com>
Signed-off-by: Phillip Potter <phil@philpotter.co.uk>
Link: https://patch.msgid.link/20260720194421.1497-2-phil@philpotter.co.uk
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2026-07-20 21:54:52 -06:00
Aditya Prakash Srivastava
21a6287ae2 ecryptfs: use filemap_dirty_folio for address space operations
ecryptfs does not use buffer_heads. The legacy block_dirty_folio and
block_invalidate_folio mapping operations were only added as a
temporary compatibility fallback under CONFIG_BLOCK.

Since ecryptfs does not attach private metadata (such as buffer_heads)
to its folios, block_dirty_folio is unnecessary.

Modernize ecryptfs to use filemap_dirty_folio for its dirty_folio
address space operation. This allows removing the block_dirty_folio
and block_invalidate_folio fallbacks, removing the buffer_head header
include, and removing the CONFIG_BLOCK dependency inside ecryptfs_aops.

Signed-off-by: Aditya Prakash Srivastava <aditya.ansh182@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2026-07-20 22:12:46 -05:00
Yichong Chen
8fafd7c86f ecryptfs: avoid heap allocation for inode size write
ecryptfs_write_inode_size_to_header() allocates an 8-byte buffer only
to write the encoded inode size to the lower file header.

Use a stack __be64 value instead. This avoids an unnecessary allocation
and removes a failure path without changing the data written to disk.

Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2026-07-20 22:12:46 -05:00
Yichong Chen
496ec2d085 ecryptfs: show filename encryption options
ecryptfs_show_options() prints most user-visible mount options but
omits the filename encryption cipher and key size.

Print ecryptfs_fn_cipher and ecryptfs_fn_key_bytes when filename
encryption is enabled so that the displayed mount options reflect the
active filename encryption settings.

Fixes: 87c94c4df0 ("eCryptfs: Filename Encryption: mount option")
Cc: <stable@vger.kernel.org>
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2026-07-20 22:12:46 -05:00
Pengpeng Hou
95540462e6 eCryptfs: bound the packet-length peek to the user buffer
ecryptfs_miscdev_write() accepts the minimum one-byte packet-length
encoding, but always copies the maximum two-byte encoding from userspace
before parsing it. A six-byte message therefore reads one byte beyond the
submitted user buffer.

Zero-initialize the peek buffer and copy only the packet-length bytes
present. The existing exact packet-size check still rejects truncated
two-byte encodings after the parser determines their encoded length.

Fixes: 8bf2debd5f ("eCryptfs: introduce device handle for userspace daemon communications")
Cc: <stable@vger.kernel.org>
Signed-off-by: Pengpeng Hou <pengpeng@iscas.ac.cn>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2026-07-20 22:12:33 -05:00
Yichong Chen
e97bbe1b2b ecryptfs: reject too-small tag 70 packets
ecryptfs_parse_tag_70_packet() subtracts fixed metadata fields from the
parsed packet body size to derive the encrypted filename size.  A
malformed packet with a body smaller than those fixed fields can underflow
that size calculation.

Reject tag 70 packets before the subtraction unless the body contains the
signature, cipher code, and at least one byte of encrypted filename data.

Fixes: 9c79f34f7e ("eCryptfs: Filename Encryption: Tag 70 packets")
Cc: <stable@vger.kernel.org>
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2026-07-20 22:11:14 -05:00
Yichong Chen
8b2ec0f56f ecryptfs: fix tag 11 packet exact-fit size check
parse_tag_11_packet() rejects a packet when the already-consumed tag and
length bytes plus the packet body exceed the caller supplied maximum
packet size.  The check currently adds one extra byte, even though
*packet_size already includes the tag byte before the length is parsed.

Remove the extra byte so a tag 11 packet that exactly fits the available
buffer is accepted while oversized packets are still rejected.

Fixes: 237fead619 ("[PATCH] ecryptfs: fs/Makefile and fs/Kconfig")
Cc: <stable@vger.kernel.org>
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2026-07-20 22:11:14 -05:00
Yichong Chen
2602b79c5b ecryptfs: pass packet set buffer size to parser
ecryptfs_parse_packet_set() receives a pointer into the file header, but
it calculates the remaining packet buffer size from PAGE_SIZE - 8.  For
version 1 headers the packet set starts later in the header, so this can
overstate the available buffer.

Pass the actual packet set buffer length from the caller and calculate
per-packet limits from the remaining bytes in that buffer.  Recompute the
remaining length after consuming a tag 3 packet before parsing the
following tag 11 packet.

Fixes: 237fead619 ("[PATCH] ecryptfs: fs/Makefile and fs/Kconfig")
Cc: <stable@vger.kernel.org>
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Signed-off-by: Tyler Hicks <code@tyhicks.com>
2026-07-20 22:11:14 -05:00
Tim Wiederhake
b096d79bc1 x86/msr: Document the I/O-like write semantics in the msr driver
Explain why msr_write() does not advance the index.

  [ bp: Massage commit message. ]

Signed-off-by: Tim Wiederhake <twiederh@redhat.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://patch.msgid.link/20260629173759.1770596-1-twiederh@redhat.com
2026-07-20 19:57:33 -07:00
Paul Moore
3693ff45ec apparmor: leverage audit_log_n_untrustedstring() when possible
Make use of the audit_log_n_untrustedstring() function to simplify the
code in aa_label_xaudit().

Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
2026-07-20 19:07:03 -07:00
Masami Hiramatsu (Google)
f418d68d71 tracing/eprobe: Fix exact system name matching in eprobe_dyn_event_match()
eprobe_dyn_event_match() checks if the target event system in argv[0]
matches ep->event_system using strncmp(ep->event_system, argv[0], len).
However, if ep->event_system is longer than len (e.g. "eprobes" vs
"ep/event"), strncmp() still returns 0 because the first len characters
match.

Check that ep->event_system[len] is '\0' to ensure exact system name
matching.

Link: https://lore.kernel.org/all/178454235856.290363.14872590900774231133.stgit@devnote2/

Fixes: 7d5fda1c84 ("tracing: Fix event probe removal from dynamic events")
Cc: stable@vger.kernel.org
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21 10:23:21 +09:00
Masami Hiramatsu (Google)
8ce20bfba4 tracing/probes: Fix potential underflow in LEN_OR_ZERO macro
In __set_print_fmt(), LEN_OR_ZERO is defined as (len ? len - pos : 0).
If len is non-zero but smaller than pos, len - pos evaluates to a negative
integer. When passed as a size argument to snprintf(), this negative value
is cast to a large unsigned size_t, bypassing buffer size limits.

Ensure len > pos before subtracting to avoid integer underflow.

Link: https://lore.kernel.org/all/178454234934.290363.15247317871499514139.stgit@devnote2/

Fixes: 5bf652aaf4 ("tracing/probes: Integrate duplicate set_print_fmt()")
Cc: stable@vger.kernel.org
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21 10:23:17 +09:00
Masami Hiramatsu (Google)
a9d6fb2840 tracing/probes: Prevent out-of-bounds write in __trace_probe_log_err()
If trace_probe_log.argc is 0 in __trace_probe_log_err(), the loop
constructing the command string will not execute and p will remain equal to
command. Writing to *(p - 1) will cause an out-of-bounds access before
command. This should not happen, but better to be treated.

Reject if trace_probe_log.argc is 0.

Link: https://lore.kernel.org/all/178454233992.290363.18323091580600697731.stgit@devnote2/

Fixes: ab105a4fb8 ("tracing: Use tracing error_log with probe events")
Cc: stable@vger.kernel.org
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21 10:23:13 +09:00
Masami Hiramatsu (Google)
15f197856d tracing/probes: Avoid temporary buffer truncation in trace_probe_match_command_args()
In trace_probe_match_command_args(), a stack buffer buf[MAX_ARGSTR_LEN + 1]
(256 bytes) is used to format "<name>=<comm>". However, since name can
be up to 32 bytes (MAX_ARG_NAME_LEN) and comm up to 255 bytes
(MAX_ARGSTR_LEN), the formatted string can exceed 256 bytes and get
truncated by snprintf(), causing spurious argument matching failures.

Instead of formatting into a temporary buffer on stack, compare the
argument name, the '=' delimiter, and the comm expression directly.

Link: https://lore.kernel.org/all/178454233010.290363.10428767141343428804.stgit@devnote2/

Fixes: eb5bf81330 ("tracing/kprobe: Add per-probe delete from event")
Cc: stable@vger.kernel.org
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2026-07-21 10:23:10 +09:00
Abdun Nihaal
e354f7d60f bnx2x: fix null pointer dereference in bnx2x_free_mem_bp()
In one of the error path in bnx2x_alloc_mem_bp(), bnx2x_free_mem_bp()
may be called with bp->fp uninitialized. And so, there could be a null
pointer dereference in bnx2x_free_mem_bp(). Fix that by initializing the
fp_array_size after the bp->fp pointer is correctly initialized.

Cc: stable+noautosel@kernel.org # untested fix to unlikely error path
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Abdun Nihaal <nihaal@cse.iitm.ac.in>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260707054618.932108-1-nihaal@cse.iitm.ac.in
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-20 18:20:31 -07:00
Zhaolong Zhang
1c975de334 bonding: fix devconf_all NULL dereference when IPv6 is disabled
When booting with the 'ipv6.disable=1' parameter, the devconf_all is
never initialized because inet6_init() exits before addrconf_init() is
called which initializes it. bond_send_validate(), however, will still
call bond_ns_send_all() even ipv6 is indeed disabled. It will lead to
NULL derefence of net->ipv6.devconf_all in ip6_pol_route().

 BUG: kernel NULL pointer dereference, address: 000000000000000c
 [...]
 Workqueue: bond0 bond_arp_monitor [bonding]
 RIP: 0010:ip6_pol_route+0x69/0x480
 [...]
 Call Trace:
  <TASK>
  ? srso_return_thunk+0x5/0x5f
  ? __pfx_ip6_pol_route_output+0x10/0x10
  fib6_rule_lookup+0xfe/0x260
  ? wakeup_preempt+0x8a/0x90
  ? srso_return_thunk+0x5/0x5f
  ? srso_return_thunk+0x5/0x5f
  ? sched_balance_rq+0x369/0x810
  ip6_route_output_flags+0xd7/0x170
  bond_ns_send_all+0xde/0x280 [bonding]
  bond_ab_arp_probe+0x296/0x320 [bonding]
  ? srso_return_thunk+0x5/0x5f
  bond_activebackup_arp_mon+0xb4/0x2c0 [bonding]
  process_one_work+0x196/0x370
  worker_thread+0x1af/0x320
  ? srso_return_thunk+0x5/0x5f
  ? __pfx_worker_thread+0x10/0x10
  kthread+0xe3/0x120
  ? __pfx_kthread+0x10/0x10
  ret_from_fork+0x199/0x260
  ? __pfx_kthread+0x10/0x10
  ret_from_fork_asm+0x1a/0x30
  </TASK>

Fix this by adding ipv6_mod_enabled() condition check in the caller.

Fixes: 4e24be018e ("bonding: add new parameter ns_targets")
Signed-off-by: Qianheng Peng <pengqh1@chinatelecom.cn>
Signed-off-by: Zhaolong Zhang <zhangzl68@chinatelecom.cn>
Reviewed-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://patch.msgid.link/20260707010622.487333-1-zhangzl2013@126.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-20 18:18:02 -07:00
Jakub Kicinski
1572d5862c Merge branch 'fix-broken-tc_act_redirect-from-qdiscs'
Daniel Borkmann says:

====================
Fix broken TC_ACT_REDIRECT from qdiscs

This is an alternative fix to [0] in order to not uglify
__dev_queue_xmit() with sprinkled ifdefs given this can be
simplified and isolated through a simple test into the BPF
redirect helper itself.

I've also added a proper BPF selftest, so there is no need
to check-in a binary BPF object into selftests given we do
have BPF infra for all of this.

  [0] https://lore.kernel.org/netdev/20260629102157.737306-1-jhs@mojatatu.com/
  [1] https://lore.kernel.org/netdev/20260629102157.737306-4-jhs@mojatatu.com/
====================

Link: https://patch.msgid.link/20260706185609.330006-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-20 18:16:46 -07:00
Daniel Borkmann
f789afed94 selftests/bpf: Add test for redirect from qdisc qevent block
Add a regression test for the NULL current->bpf_net_context deref hit
when a BPF classifier attached to a qdisc qevent block asks for a
redirect. The classifier runs from tcf_qevent_handle() on the qdisc
enqueue path, outside any bpf_net_context.

  # LDLIBS=-static PKG_CONFIG='pkg-config --static' ./vmtest.sh -- ./test_progs -t qevent
  [...]
  + /etc/rcS.d/S50-startup
  ./test_progs -t qevent
  #496/1   tc_qevent/redirect_verdict:OK
  #496/2   tc_qevent/redirect_helper:OK
  #496     tc_qevent:OK
  Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://patch.msgid.link/20260706185609.330006-4-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-20 18:16:43 -07:00
Jamal Hadi Salim
ec48b3be2c net/sched: Handle TC_ACT_REDIRECT from qdisc filter chains
When a TC filter attached to a qdisc filter chain returns
TC_ACT_REDIRECT (ex: via an eBPF program calling bpf_redirect() or an
act_bpf action), the redirect was silently lost i.e no qdisc classify
function handled TC_ACT_REDIRECT, so the packet fell through the
switch and was enqueued normally instead of being redirected.

This has been broken since bpf_redirect() was introduced for TC in
commit 27b29f6305 ("bpf: add bpf_redirect() helper"). We got lucky
for a long time because bpf_net_context was a per-CPU variable that
was always available.

commit 401cb7dae8 ("net: Reference bpf_redirect_info via task_struct
on PREEMPT_RT.") turned bpf_net_context into a task_struct member that
is only set up by explicit callers. Without a caller setting it up,
bpf_redirect() itself crashes with a NULL pointer dereference in
bpf_net_ctx_get_ri(). However, even with bpf_net_context available,
TC_ACT_REDIRECT from qdisc filter chains cannot be honored without
adding skb_do_redirect() calls to every qdisc classify function, which
would require changes across net/sched/. Isolate it to ebpf core where
it belongs.

Instead, add a tcf_classify_qdisc() inline helper in pkt_cls.h, as a
wrapper around tcf_classify() for use by qdisc classify functions and
tcf_qevent_handle(). When the classify verdict is TC_ACT_REDIRECT,
the wrapper converts it to TC_ACT_SHOT, dropping the packet rather
than letting it continue silently. Dropping is preferred over
letting the packet through because the user immediately sees packet
loss. Silently passing the packet through would hide the problem and
leave the user wondering why their redirect is not working.

The clsact fast path, tc_run() continues to call tcf_classify() directly
and is unaffected: TC_ACT_REDIRECT is returned as-is and handled by
sch_handle_egress/ingress() calling skb_do_redirect() as before.

Fixes: 27b29f6305 ("bpf: add bpf_redirect() helper")
Fixes: 401cb7dae8 ("net: Reference bpf_redirect_info via task_struct on PREEMPT_RT.")
Tested-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://patch.msgid.link/20260706185609.330006-3-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-20 18:16:43 -07:00
Daniel Borkmann
3f4920d165 bpf: Reject redirect helpers without a bpf_net_context
The bpf_redirect*() helpers and skb_do_redirect() obtain the per-task
bpf_redirect_info via bpf_net_ctx_get_ri(), which dereferences the
current->bpf_net_context unconditionally. That context is established
on the paths that run tc BPF such as sch_handle_{ingress,egress}(),
*except* for the case where {cls,act}_bpf was attached to a proper
qdisc. A program running from there reaches the NULL deref in two ways:

* It calls bpf_redirect() directly, which dereferences the context at
  the top of the helper:

     tc qdisc add dev eth0 root handle 1: red limit 1MB min 10KB max 20KB \
        avpkt 1000 burst 100 qevent early_drop block 10
     tc filter add block 10 pref 1 bpf obj redirect.o

* It simply returns TC_ACT_REDIRECT without helper call: tcf_qevent_handle()
  then dispatches to skb_do_redirect(), which dereferences the context

Rather than extending bpf_net_context management into the qdisc path,
make the redirect helpers refuse to operate when no context exists, and
have tcf_qevent_handle() drop a TC_ACT_REDIRECT verdict instead of
calling skb_do_redirect(). Previous behaviour was a crash, so nothing
regresses by not supporting it.

Fixes: 401cb7dae8 ("net: Reference bpf_redirect_info via task_struct on PREEMPT_RT.")
Fixes: 3625750f05 ("net: sched: Introduce helpers for qevent blocks")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://patch.msgid.link/20260706185609.330006-2-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-20 18:16:42 -07:00
David Lee
50aff80475 net/packet: avoid fanout hook re-registration after unregister
packet_set_ring() temporarily detaches a socket from packet delivery while
reconfiguring its ring. It records the previous running state, clears
po->num, unregisters the protocol hook when needed, drops po->bind_lock,
and later restores po->num and re-registers the hook from the saved
was_running value.

That unlocked window can race with NETDEV_UNREGISTER. The notifier can
observe the socket as not running, skip __unregister_prot_hook(), and
invalidate the per-socket binding by setting po->ifindex to -1 and clearing
po->prot_hook.dev. A one-member fanout group can still retain its shared
fanout hook device pointer. When packet_set_ring() resumes, re-registering
solely from the stale was_running state can re-add the fanout hook after
the device has been unregistered.

Treat po->ifindex == -1 as an invalidated binding after reacquiring
po->bind_lock. This is distinct from ifindex 0, the normal
unbound/wildcard state: ifindex -1 marks an existing device binding that
was invalidated when the device was unregistered. Restore po->num as
before, but do not re-register the hook if device unregister already
detached the socket.

Fixes: dc99f60069 ("packet: Add fanout support.")
Link: https://lore.kernel.org/netdev/20260701113947.23180-1-david.lee@trailofbits.com/
Signed-off-by: David Lee <david.lee@trailofbits.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260707104440.833129-1-david.lee@trailofbits.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-20 18:15:20 -07:00
Danielle Ratson
f6e3b21608 netlink: specs: rt-link: convert bridge port flag attributes to u8
A number of IFLA_BRPORT_* attributes are documented in the rt-link spec
as having the "flag" type, i.e. a payload-less NLA_FLAG attribute whose
meaning is presence-only. This does not match the kernel, which emits
these attributes with nla_put_u8() and validates them as NLA_U8 in
br_port_policy[]. The values are not mere presence flags but carry a u8
payload (0/1).

Convert these bridge port attributes from "flag" to "u8" so the spec
reflects the actual wire format.

Fixes: 077b6022d2 ("doc/netlink/specs: Add sub-message type to rt_link family")
Reviewed-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Danielle Ratson <danieller@nvidia.com>
Link: https://patch.msgid.link/a57cdfcfc4a6dcb92106c25b4dde5059fde2bd44.1783236731.git.danieller@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-20 18:14:42 -07:00
Ricardo B. Marlière
ef01724fa2 selftests/net: Fix tun IPv6 test addresses to avoid 6to4 range
The IPv6 addresses used for the tun_vnet_udptnl fixture currently fall in
the 2002::/16 prefix, which is reserved for the 6to4 transition mechanism
(RFC 3056).

On systems where the sit module is loaded, the kernel automatically claims
2002::/16 as a 6to4 tunnel prefix. When the test assigns a 2002:: address
to a TUN interface, sit registers a competing local route for the same
address. This ambiguity breaks the GENEVE decapsulation path: packets
injected via the TUN fd are not delivered to the test socket, causing the
IPv6-outer gtgso send_gso_packet variants to fail.

Replace all four IPv6 test addresses with addresses from the fd00:db8::/32
range, which is part of the ULA space (fc00::/7, RFC 4193) and carries no
special kernel semantics.

Fixes: 24e59f26ee ("selftest: tun: Add helpers for GSO over UDP tunnel")
Signed-off-by: Ricardo B. Marlière <rbm@suse.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260706-b4-net_tun_addr-v1-1-3d3cb2473560@suse.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-20 17:59:25 -07:00
Michael Walle
7d8ca62d6a net: phy: marvell: fix return code
Return the correct error code, not the value written to the register.

Fixes: a219912e0f ("net: phy: marvell: implement config_inband() method")
Signed-off-by: Michael Walle <mwalle@kernel.org>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://patch.msgid.link/20260706120637.1947685-1-mwalle@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-07-20 17:51:46 -07:00
Kiryl Shutsemau (Meta)
40de8160ca fs/proc/task_mmu: fix PAGEMAP_SCAN written state for PMD holes
PAGEMAP_SCAN reports an unpopulated PTE in a uffd-wp VMA as written, but a
range with no page table at all -- a PMD hole -- is skipped:
pagemap_scan_pte_hole() tests p->cur_vma_category, which never carries
PAGE_IS_WRITTEN, so the hole is neither reported nor (under
PM_SCAN_WP_MATCHING) armed.

In a uffd-wp VMA, WP_UNPOPULATED installs uffd-wp markers when protecting
a range, allocating page tables as needed, so an unpopulated slot is
treated as written -- see the pte_none() handling in
pagemap_page_category().  A missing marker therefore means the range was
zapped, e.g.  via MADV_DONTNEED.  This applies to anon and shmem VMAs.

An anonymous THP is write-protected in place as a huge PMD, so a full-PMD
MADV_DONTNEED clears it to pmd_none -- a hole with no page table -- and
pagemap_scan_pte_hole() misses it.  For a MAP_PRIVATE|MAP_ANON mapping
MADV_DONTNEED has fill-with-zeros semantics, so a write-tracking
checkpoint/migration tool (e.g.  CRIU) treats the range as unchanged and
keeps its previous contents; after restore or live migration the process
reads stale data instead of zeroes -- data corruption.

Report a hole in a non-hugetlb uffd-wp VMA as written, matching the
pte_none handling in pagemap_page_category(); the existing
PM_SCAN_WP_MATCHING path then arms it via uffd_wp_range().

hugetlb is excluded: pagemap_hugetlb_category() reports an empty hugetlb
entry (huge_pte_none) as not-written, unlike pagemap_page_category(),
which reports pte_none as written.  pagemap_scan_pte_hole() fires for a
hugetlb slot only when it has no page table; keeping that not-written
matches how an allocated-but-empty hugetlb entry reads, so the hole and
the empty-entry cases agree within the VMA.

Link: https://lore.kernel.org/20260715144234.442721-2-kirill@shutemov.name
Fixes: 2bad466cc9 ("mm/uffd: UFFD_FEATURE_WP_UNPOPULATED")
Signed-off-by: Kiryl Shutsemau <kas@kernel.org>
Reported-by: Sashiko AI review <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260707151349.92143-1-kirill@shutemov.name
Tested-by: Muhammad Usama Anjum <usama.anjum@arm.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: Zenghui Yu <zenghui.yu@linux.dev>
Assisted-by: Claude:claude-fable-5
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:29 -07:00
Xiangfeng Cai
dd9623f58e mm/hugetlb: fix list corruption in allocate_file_region_entries()
allocate_file_region_entries() tops up resv->region_cache with freshly
allocated file_region descriptors.  The allocation uses GFP_KERNEL, so
resv->lock is dropped around it: the new entries are gathered on a
stack-local list head, allocated_regions, and spliced into
resv->region_cache once the lock is re-acquired.

The splice used list_splice(), which moves the entries but does not
re-initialize the source head, so allocated_regions is left pointing at an
entry that now lives on resv->region_cache.  The top-up runs in a while
loop that re-checks the cache deficit after re-acquiring the lock.  For a
shared mapping the resv_map is shared by every mapper of the hugetlbfs
inode, so a concurrent region_chg()/region_add()/region_del() on the same
resv_map can consume cache entries during the unlocked window and force a
second iteration.  That iteration calls list_add() on the stale head and
corrupts the list; with CONFIG_DEBUG_LIST the __list_add_valid() check
trips:

  list_add corruption. next->prev should be prev (ffffc900011ff7f8),
  but was ffff88814c281460. (next=ffff88814c545640).
  kernel BUG at lib/list_debug.c:31!
   allocate_file_region_entries+0x191/0x420
   region_chg+0x267/0x300
   hugetlb_reserve_pages+0x387/0xc80
   hugetlbfs_file_mmap+0x2ce/0x3f0
   mmap_region+0x1348/0x1a80
   do_mmap+0x85e/0xb90
   vm_mmap_pgoff+0x18c/0x330
   ksys_mmap_pgoff+0x2a1/0x3e0
   do_syscall_64+0xd7/0x420

Without CONFIG_DEBUG_LIST the bad list_add() silently links a kernel-stack
address into resv->region_cache, leading to later use-after-free.

This was observed as a real host panic on a dense KVM host where a QEMU
guest-RAM hugetlbfs file was mapped MAP_SHARED by both QEMU and a separate
SPDK/DPDK vhost-user target, generating concurrent region_* traffic on one
shared resv_map.

Use list_splice_init() so the source head is re-initialized empty after
each splice, making the retry loop safe.

Link: https://lore.kernel.org/20260713171456.300518-2-caixiangfeng@bytedance.com
Fixes: d3ec7b6e09 ("mm/hugetlb: use list_splice to merge two list at once")
Signed-off-by: Xiangfeng Cai <caixiangfeng@bytedance.com>
Reviewed-by: Muchun Song <muchun.song@linux.dev>
Cc: Baoquan He <baoquan.he@linux.dev>
Cc: David Hildenbrand <david@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:28 -07:00
Qi Zheng
de4660898b mm: mglru: fix stale batch updates after memcg reparenting
The mglru page table walker batches per-generation size deltas in
walk->nr_pages while walking page tables without holding the lruvec lock. 
The reset_batch_size() later folds those deltas into walk->lruvec under
the lruvec lock.

The page table walker can run concurrently with the memcg reparenting path
as follows:

CPU0                           CPU1
====                           ====

walk_mm
--> walk_page_range
    --> update_batch_size
        --> walk->nr_pages += delta

                              mem_cgroup_css_offline
                              --> memcg_reparent_objcgs
                                  --> lock lruvec
                                      lru_gen_reparent_memcg
                                      --> reparent child folios to parent
                                      unlock lruvec

    lock lruvec
    reset_batch_size
    --> child lrugen->nr_pages += delta

This will trigger the following warning in lru_gen_exit_memcg():

	VM_WARN_ON_ONCE(memchr_inv(lruvec->lrugen.nr_pages, 0,
				   sizeof(lruvec->lrugen.nr_pages)));

And the user-visible impact of underestimated nr_pages in MGLRU was
premature OOMs because MGLRU does not try to reclaim memory when nr_pages
reaches zero, but there are still more pages.

To fix it, make reset_batch_size() check CSS_DYING under RCU before
flushing the pending batch.  A non-dying memcg keeps the original lruvec
stable against RCU-delayed offlining; a dying memcg redirects the deltas
to the first non-dying ancestor.

Link: https://lore.kernel.org/20260710154318.75388-1-qi.zheng@linux.dev
Fixes: f304652609 ("mm: vmscan: prepare for reparenting MGLRU folios")
Signed-off-by: Qi Zheng <zhengqi.arch@bytedance.com>
Reported-by: Peiyang He <peiyang_he@smail.nju.edu.cn>
Closes: https://lore.kernel.org/all/5A9E929D82717101+12fcf643-efb8-4b9a-a53a-1e28cc894f0b@smail.nju.edu.cn
Reviewed-by: Harry Yoo (Oracle) <harry@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Barry Song <baohua@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: Kairui Song <kasong@tencent.com>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Wei Xu <weixugc@google.com>
Cc: Yuanchu Xie <yuanchu@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:28 -07:00
Jori Koolstra
e3a0127eee selftest: fix headers in fclog.c
fclog.c does not compile because it is missing fcntl.h, needed for
O_RDONLY etc.

There are also some redundant includes that are also in
kselftest_harness.h.

Link: https://lore.kernel.org/20260710171741.837308-1-jkoolstra@xs4all.nl
Signed-off-by: Jori Koolstra <jkoolstra@xs4all.nl>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:28 -07:00
Joseph Qi
df8ce7ab48 ocfs2: fix boundary check in ocfs2_check_dir_entry() to use buffer offset
Commit 390ac56cf0 ("ocfs2: add boundary check to
ocfs2_check_dir_entry()") added an out-of-bounds guard using the
caller-supplied 'offset' argument:

	if (offset > size - OCFS2_DIR_REC_LEN(1))
		return 0;

However, 'offset' and 'size' are not measured against the same base for
all callers.  In the block-based lookup path, ocfs2_find_entry_el() passes
'offset' as an absolute offset into the whole directory:

	i = ocfs2_search_dirblock(bh, dir, name, namelen,
				  block << sb->s_blocksize_bits,
				  bh->b_data, sb->s_blocksize, res_dir);

while 'size' is a single block size (sb->s_blocksize).  For any directory
entry located in the second or later block, 'offset' is >=
sb->s_blocksize, so the guard rejects every such entry even though it is
perfectly valid and lies entirely within its block buffer.

This makes mounting fail for filesystems whose system directory spans more
than one block, e.g.  a volume formatted with a small block size:

  mkfs.ocfs2 -b 512 -C 4096 -N 2 -T datafiles --fs-features=usrquota,grpquota

  ocfs2_check_dir_entry:314 ERROR: directory entry (#18: offset=512) too close to end or out-of-bounds
  ocfs2_init_local_system_inodes:496 ERROR: status=-22, sysfile=12, slot=0
  ocfs2_mount_volume:1757 ERROR: status = -22

The dirent's position within the buffer being validated is ((char *)de -
buf), which is what the rest of the function already uses (via
next_offset) and what must be bounds-checked against 'size'.  Compute that
buffer-relative offset and use it for the guard.  The subtraction is
reordered to size - buf_offset < OCFS2_DIR_REC_LEN(1) to avoid an unsigned
underflow when size is smaller than the minimal record length.

Link: https://lore.kernel.org/20260710040512.3310736-1-joseph.qi@linux.alibaba.com
Fixes: 390ac56cf0 ("ocfs2: add boundary check to ocfs2_check_dir_entry()")
Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Dmitry Antipov <dmantipov@yandex.ru>
Tested-by: Dmitry Antipov <dmantipov@yandex.ru>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Cc: Heming Zhao <heming.zhao@suse.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:28 -07:00
Zi Yan
89b1b79c30 mm/percpu-km: fix bitmap overflow and accounting in pcpu_create_chunk()
In pcpu_create_chunk(), nr_pages is the total contiguous backing
allocation, i.e., nr_units * pcpu_unit_pages, but pcpu_chunk_populated()
uses it to set chunk->populated, whose size is pcpu_unit_pages, bitmap. 
Since bit N in chunk->populated means page offset N inside every unit is
backed.  When nr_units > 1, the function writes beyond chunk->populated. 
Fix it by using chunk->nr_pages.

It also fixes the global pcpu_nr_empty_pop_pages accounting, since
pcpu_balance_free() only iterates up to chunk->nr_pages.

Commit a63d4ac4ab ("percpu: make percpu-km set chunk->populated bitmap
properly") introduced the bitmap overflow issue.  Later, commit
b539b87fed ("percpu: implmeent pcpu_nr_empty_pop_pages and
chunk->nr_populated") added pcpu_nr_empty_pop_pages and caused the
accounting issue.

Link: https://lore.kernel.org/20260709-fix-pcpu_create_chunk-in-percpu-km-v1-1-1f64745a84cc@nvidia.com
Fixes: a63d4ac4ab ("percpu: make percpu-km set chunk->populated bitmap properly")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://sashiko.dev/#/patchset/20260703-keep-subpage-private-zero-at-free-v2-0-2970fe777dd6%40nvidia.com?part=1
Assisted-by: Codex:GPT-5
Signed-off-by: Zi Yan <ziy@nvidia.com>
Acked-by: Dennis Zhou <dennis@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:27 -07:00
Aboorva Devarajan
7441d6348c mm/util: don't read __page_2 for order-1 folios in snapshot_page()
snapshot_page() currently reads __page_2 after checking nr_pages > 1, but
it should only do so when nr_pages > 2.

If an order-1 folio is allocated at the end of a vmemmap section,
__page_2 will not exist and reading it will cause a fault.

During DLPAR memory remove on a 22 TB ppc64le LPAR, snapshot_page() oopsed
on the page isolation path while reading an order-1 folio's __page_2 from
an adjacent absent section (unmapped vmemmap).

Fix this to avoid reading memmap that doesn't exist (e.g., a vmemmap
hole).

Link: https://lore.kernel.org/20260708201954.686111-1-aboorvad@linux.ibm.com
Fixes: 31a31da8a6 ("mm: move _pincount in folio to page[2] on 32bit")
Signed-off-by: Aboorva Devarajan <aboorvad@linux.ibm.com>
Reported-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Lorenzo Stoakes <ljs@kernel.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Luiz Capitulino <luizcap@redhat.com>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: "Ritesh Harjani (IBM)" <ritesh.list@gmail.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: <stable@vger.kernel.org> # v6.15+
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:27 -07:00
Kiryl Shutsemau (Meta)
83abe2fd5b mm/hugetlb: fix swap entry corruption when clearing uffd-wp at fork()
copy_hugetlb_page_range() clears the uffd-wp bit of migration and hwpoison
entries with huge_pte_clear_uffd_wp(), which operates on the present-PTE
bit position.  Swap entries keep the uffd-wp state elsewhere -- the
migration branch reads and sets it with pte_swp_uffd_wp() and
pte_swp_mkuffd_wp() -- and the present-PTE position falls into the swap
payload.  On x86-64 it lands in the inverted swap offset, where a
naturally-aligned hugetlb PFN always has the affected bit set, so the
clear advances the encoded PFN by two pages.

No userfaultfd needs to be involved: the clear is guarded only by the
child VMA not being uffd-wp registered, so a plain fork() with an
in-flight hugetlb migration entry (or a poisoned hugetlb page) corrupts
the entry copied into the child.  Instrumenting the clear and forking
after MADV_HWPOISON on a 2MB anon hugetlb page shows:

  offset before=120e00
  offset after =120e02

The fallout is mostly latent: rmap walks match migration entries by folio
range and remove_migration_pte() rebuilds the PTE from the folio, so a
within-folio PFN skew heals once migration completes.  But any path that
re-encodes the corrupted offset -- e.g.  hugetlb_change_protection()
rewriting a writable migration entry via
make_readable_migration_entry(swp_offset(entry)) -- propagates it.

Migration entries legitimately carry uffd-wp, so clear it with
pte_swp_clear_uffd_wp(), matching copy_nonpresent_pte() and
move_huge_pte().

A hwpoison entry, on the other hand, never carries the uffd-wp bit: it is
installed fresh by make_hwpoison_entry() (try_to_unmap_one() does not
preserve uffd-wp on the hwpoison path) and hugetlb_change_protection()
leaves hwpoison entries untouched.  There was nothing to clear there, only
the corruption, so drop the clear entirely.

Link: https://lore.kernel.org/20260708090110.136162-1-kirill@shutemov.name
Fixes: bc70fbf269 ("mm/hugetlb: handle uffd-wp during fork()")
Signed-off-by: Kiryl Shutsemau <kas@kernel.org>
Reported-by: Sashiko AI review <sashiko-bot@kernel.org>
Closes: https://lore.kernel.org/all/20260703140011.99E601F000E9@smtp.kernel.org/
Suggested-by: David Hildenbrand <david@kernel.org>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Assisted-by: Claude:claude-fable-5
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:27 -07:00
Kefeng Wang
63867c82d0 mm: migrate_device: fix pte_pfn/pte_dirty called on non-present PTE
pte_pfn() and pte_dirty() have undefined behaviour when called on a
non-present PTE. In migrate_vma_collect_pmd(), these functions may be
invoked on non-present entries (e.g., device-private entries), leading
to potential crashes from pte_pfn() or incorrect dirty folio accounting
from pte_dirty(). Fix both by guarding with pte_present() checks.

Link: https://lore.kernel.org/20260708003955.4024340-1-wangkefeng.wang@huawei.com
Link: https://lore.kernel.org/20260706111958.3649651-1-wangkefeng.wang@huawei.com
Fixes: fd35ca3d12 ("mm/migrate_device.c: copy pte dirty bit to page")
Fixes: 6c287605fd ("mm: remember exclusively mapped anonymous pages with PG_anon_exclusive")
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Balbir Singh <balbirs@nvidia.com>
Acked-by: Zi Yan <ziy@nvidia.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Byungchul Park <byungchul@sk.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Gregory Price <gourry@gourry.net>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Joshua Hahn <joshua.hahnjy@gmail.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Rakie Kim <rakie.kim@sk.com>
Cc: Ying Huang <ying.huang@linux.alibaba.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:27 -07:00
Kiryl Shutsemau (Meta)
07b4377bdb fs/proc/task_mmu: fix PAGEMAP_SCAN written state for unpopulated ptes
PAGEMAP_SCAN reports an unpopulated pte differently depending on which
path serves the request.  The PAGE_IS_WRITTEN fast path in
pagemap_scan_pmd_entry() reports a pte_none as written (and, under
PM_SCAN_WP_MATCHING, arms a marker); pagemap_page_category() returns 0 for
the same pte_none.  A request that cannot take the fast path (an extra
category bit, category_anyof_mask or category_inverted) therefore reports
the pte as clean and skips arming it.

A range that was populated and then MADV_DONTNEED'd reads as written via
one mask and clean via another, and in the latter case is not re-armed for
the next round -- an incremental-dump consumer (e.g.  CRIU) using a richer
mask drops the zapped range and stops tracking writes to it.

Report pte_none as written in pagemap_page_category() too.  A pte_none
carries no uffd-wp marker, i.e.  it is not write-protected -- the same
condition under which the present and swap cases already report
PAGE_IS_WRITTEN.  The fast path applies no VMA test, so neither does this.

The hugetlb and fully-unpopulated-PMD (no page table) scans have no
PAGE_IS_WRITTEN fast path, so they do not exhibit the per-entry divergence
and are left unchanged.

Add a pagemap_ioctl selftest that populates a range, drops it with
MADV_DONTNEED, and checks that the fast path and the generic
(category_anyof_mask) path both report every page written.

Link: https://lore.kernel.org/20260707151349.92143-1-kirill@shutemov.name
Fixes: 12f6b01a0b ("fs/proc/task_mmu: add fast paths to get/clear PAGE_IS_WRITTEN flag")
Signed-off-by: Kiryl Shutsemau <kas@kernel.org>
Cc: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Lorenzo Stoakes <ljs@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Pedro Falcato <pfalcato@suse.de>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@kernel.org>
Assisted-by: Claude:claude-fable-5
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:26 -07:00
Usama Arif
4165b7d1c4 userfaultfd: wait on source PMD during UFFDIO_MOVE
move_pages_huge_pmd() snapshots src_pmdval under src_ptl, drops the lock,
and, for migration entries, waits with pmd_migration_entry_wait().

Passing &src_pmdval is wrong.  pmd_migration_entry_wait() must lock and
re-read the real page-table PMD; on split-PMD-lock kernels, a stack
address also resolves to the wrong lock.  softleaf_entry_wait_on_locked()
then waits without a folio reference, which is safe only while serialized
against migration-entry removal by the real PT lock.

Pass src_pmd, matching __handle_mm_fault() and hmm_vma_walk_pmd().

Link: https://lore.kernel.org/20260705131231.1499198-1-usama.arif@linux.dev
Fixes: adef440691 ("userfaultfd: UFFDIO_MOVE uABI")
Reported-by: sashiko-bot <sashiko-bot@kernel.org>
Link: https://sashiko.dev/#/patchset/20260703173903.3789516-1-usama.arif%40linux.dev?part=8
Signed-off-by: Usama Arif <usama.arif@linux.dev>
Reviewed-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Lance Yang <lance.yang@linux.dev>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Lance Yang <lance.yang@linux.dev>
Reviewed-by: Lorenzo Stoakes <ljs@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Dev Jain <dev.jain@arm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Nico Pache <npache@redhat.com>
Cc: Ryan Roberts <ryan.roberts@arm.com>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Zi Yan <ziy@nvidia.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:26 -07:00
Stanislav Kinsburskii
4fc0892353 lib: test_hmm: use device devt for coherent device range selection
Commit af69016dab ("lib: test_hmm: implement a device release method")
moved the initial dmirror_allocate_chunk() call before cdev_device_add(). 
That means the struct cdev has not been added yet, so cdev_add() has not
initialized mdevice->cdevice.dev.

The coherent-device range selection uses the device minor to choose
between spm_addr_dev0 and spm_addr_dev1.  Reading
MINOR(mdevice->cdevice.dev) before cdev_add() therefore always sees an
uninitialized dev_t.  As a result, both coherent devices select the same
physical range, and adding the second device fails due to the overlapping
dev_pagemap range.

Use mdevice->device.devt instead.  It is initialized in
dmirror_device_init() before dmirror_allocate_chunk() is called and is the
same dev_t later passed to cdev_device_add().

Link: https://lore.kernel.org/178277581197.172200.16265155329935822153.stgit@skinsburskii
Fixes: af69016dab ("lib: test_hmm: implement a device release method")
Signed-off-by: Stanislav Kinsburskii <skinsburskii@gmail.com>
Reviewed-by: Alistair Popple <apopple@nvidia.com>
Cc: Balbir Singh <balbirs@nvidia.com>
Cc: Zenghui Yu (Huawei) <zenghui.yu@linux.dev>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:26 -07:00
Gregory Price
ea3034b2b0 mm/vmstat: fold stranded per-cpu node stats when a node comes online
A per-node vmstat counter is pgdat->vm_stat[] plus per-cpu deltas.  A
balanced counter can sit split as global=+N / per-cpu=-N.

The folds reconciling the split only walk online nodes, so when
try_offline_node() marks a node offline the per-cpu deltas are stranded.

A subsequent online resets the per-cpu area but not pgdat->vm_stat[],
orphaning the +N permanently.  All NR_VM_NODE_STAT_ITEMS are affected.

The existing code zeroes the per-cpu counters and causes a permanent skew.
Fold the stranded deltas instead, before the node rejoins the online set.
The node is not online yet and the hotplug lock is held, so the remote
access to per-cpu values is safe.

Discovered when node compaction hung for a nearly empty node, as the math
to determine throttling broke.  Reproduced by repeated memory
hotplug/unplug cycles on a node under pressure: NR_ISOLATED_ANON ratchets
up and never returns to zero.

Link: https://lore.kernel.org/20260627202243.758289-1-gourry@gourry.net
Fixes: 75ef718405 ("mm, vmstat: add infrastructure for per-node vmstats")
Signed-off-by: Gregory Price <gourry@gourry.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Vlastimil Babka <vbabka@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-07-20 17:41:25 -07:00
Richard Weinberger
4a2e540947 ata: libata-sff: don't busy-wait for PIO data-in command completion
Unlike PIO data-out, the PIO data-in protocol raises no completion
interrupt, the last interrupt announces the final data block, and once
the host has drained it from the data register the ending status must
be obtained synchronously.  ata_sff_hsm_move() does this by spinning
in ata_wait_idle() for up to 10ms.

Usually this is not a big deal unless the device is slow.  In my case
it's a CF card which keeps BSY asserted for multiple milliseconds(!)
after the final data block.  Since the waiting happens in the
interrupt handler, under the port lock with interrupts disabled, the
CPU is hogged for milliseconds on every read command.

To improve the situation, bound the inline wait to ~100us.  If the
device is still busy after that, mark the command ATA_TFLAG_POLLING,
so the interrupt handler won't race for it, and obtain the ending
status via ata_sff_pio_task(), which sleeps between status checks
instead of spinning with the lock held.

Since ata_sff_pio_task() may now finish a data-in command, it must
wait for both BSY and DRQ to clear at HSM_ST_LAST, matching what
ata_wait_idle() enforced.

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
2026-07-21 08:55:31 +09:00