Commit Graph

182 Commits

Author SHA1 Message Date
Linus Torvalds
334fbe734e mm.git review status for linus..mm-stable
Everything:
 
 Total patches:       368
 Reviews/patch:       1.56
 Reviewed rate:       74%
 
 Excluding DAMON:
 
 Total patches:       316
 Reviews/patch:       1.77
 Reviewed rate:       81%
 
 Excluding DAMON and zram:
 
 Total patches:       306
 Reviews/patch:       1.81
 Reviewed rate:       82%
 
 Excluding DAMON, zram and maple_tree:
 
 Total patches:       276
 Reviews/patch:       2.01
 Reviewed rate:       91%
 
 Significant patch series in this merge:
 
 - The 30 patch series "maple_tree: Replace big node with maple copy"
   from Liam Howlett is mainly prepararatory work for ongoing development
   but it does reduce stack usage and is an improvement.
 
 - The 12 patch series "mm, swap: swap table phase III: remove swap_map"
   from Kairui Song offers memory savings by removing the static swap_map.
   It also yields some CPU savings and implements several cleanups.
 
 - The 2 patch series "mm: memfd_luo: preserve file seals" from Pratyush
   Yadav adds file seal preservation to LUO's memfd code.
 
 - The 2 patch series "mm: zswap: add per-memcg stat for incompressible
   pages" from Jiayuan Chen adds additional userspace stats reportng to
   zswap.
 
 - The 4 patch series "arch, mm: consolidate empty_zero_page" from Mike
   Rapoport implements some cleanups for our handling of ZERO_PAGE() and
   zero_pfn.
 
 - The 2 patch series "mm/kmemleak: Improve scan_should_stop()
   implementation" from Zhongqiu Han provides an robustness improvement and
   some cleanups in the kmemleak code.
 
 - The 4 patch series "Improve khugepaged scan logic" from Vernon Yang
   "improves the khugepaged scan logic and reduces CPU consumption by
   prioritizing scanning tasks that access memory frequently".
 
 - The 2 patch series "Make KHO Stateless" from Jason Miu simplifies
   Kexec Handover by "transitioning KHO from an xarray-based metadata
   tracking system with serialization to a radix tree data structure that
   can be passed directly to the next kernel"
 
 - The 3 patch series "mm: vmscan: add PID and cgroup ID to vmscan
   tracepoints" from Thomas Ballasi and Steven Rostedt enhances vmscan's
   tracepointing.
 
 - The 5 patch series "mm: arch/shstk: Common shadow stack mapping helper
   and VM_NOHUGEPAGE" from Catalin Marinas is a cleanup for the shadow
   stack code: remove per-arch code in favour of a generic implementation.
 
 - The 2 patch series "Fix KASAN support for KHO restored vmalloc
   regions" from Pasha Tatashin fixes a WARN() which can be emitted the KHO
   restores a vmalloc area.
 
 - The 4 patch series "mm: Remove stray references to pagevec" from Tal
   Zussman provides several cleanups, mainly udpating references to "struct
   pagevec", which became folio_batch three years ago.
 
 - The 17 patch series "mm: Eliminate fake head pages from vmemmap
   optimization" from Kiryl Shutsemau simplifies the HugeTLB vmemmap
   optimization (HVO) by changing how tail pages encode their relationship
   to the head page.
 
 - The 2 patch series "mm/damon/core: improve DAMOS quota efficiency for
   core layer filters" from SeongJae Park improves two problematic
   behaviors of DAMOS that makes it less efficient when core layer filters
   are used.
 
 - The 3 patch series "mm/damon: strictly respect min_nr_regions" from
   SeongJae Park improves DAMON usability by extending the treatment of the
   min_nr_regions user-settable parameter.
 
 - The 3 patch series "mm/page_alloc: pcp locking cleanup" from Vlastimil
   Babka is a proper fix for a previously hotfixed SMP=n issue.  Code
   simplifications and cleanups ennsed.
 
 - The 16 patch series "mm: cleanups around unmapping / zapping" from
   David Hildenbrand implements "a bunch of cleanups around unmapping and
   zapping.  Mostly simplifications, code movements, documentation and
   renaming of zapping functions".
 
 - The 6 patch series "support batched checking of the young flag for
   MGLRU" from Baolin Wang supports batched checking of the young flag for
   MGLRU.  It's part cleanups; one benchmark shows large performance
   benefits for arm64.
 
 - The 5 patch series "memcg: obj stock and slab stat caching cleanups"
   from Johannes Weiner provides memcg cleanup and robustness improvements.
 
 - The 5 patch series "Allow order zero pages in page reporting" from
   Yuvraj Sakshith enhances page_reporting's free page reporting - it is
   presently and undesirably order-0 pages when reporting free memory.
 
 - The 6 patch series "mm: vma flag tweaks" from Lorenzo Stoakes is
   cleanup work following from the recent conversion of the VMA flags to a
   bitmap.
 
 - The 10 patch series "mm/damon: add optional debugging-purpose sanity
   checks" from SeongJae Park adds some more developer-facing debug checks
   into DAMON core.
 
 - The 2 patch series "mm/damon: test and document power-of-2
   min_region_sz requirement" from SeongJae Park adds an additional DAMON
   kunit test and makes some adjustments to the addr_unit parameter
   handling.
 
 - The 3 patch series "mm/damon/core: make passed_sample_intervals
   comparisons overflow-safe" from SeongJae Park fixes a hard-to-hit time
   overflow issue in DAMON core.
 
 - The 7 patch series "mm/damon: improve/fixup/update ratio calculation,
   test and documentation" from SeongJae Park is a "batch of misc/minor
   improvements and fixups" for DAMON.
 
 - The 4 patch series "mm: move vma_(kernel|mmu)_pagesize() out of
   hugetlb.c" from David Hildenbrand fixes a possible issue with dax-device
   when CONFIG_HUGETLB=n.  Some code movement was required.
 
 - The 6 patch series "zram: recompression cleanups and tweaks" from
   Sergey Senozhatsky provides "a somewhat random mix of fixups,
   recompression cleanups and improvements" in the zram code.
 
 - The 11 patch series "mm/damon: support multiple goal-based quota
   tuning algorithms" from SeongJae Park extend DAMOS quotas goal
   auto-tuning to support multiple tuning algorithms that users can select.
 
 - The 4 patch series "mm: thp: reduce unnecessary
   start_stop_khugepaged()" from Breno Leitao fixes the khugpaged sysfs
   handling so we no longer spam the logs with reams of junk when
   starting/stopping khugepaged.
 
 - The 3 patch series "mm: improve map count checks" from Lorenzo Stoakes
   provides some cleanups and slight fixes in the mremap, mmap and vma
   code.
 
 - The 5 patch series "mm/damon: support addr_unit on default monitoring
   targets for modules" from SeongJae Park extends the use of DAMON core's
   addr_unit tunable.
 
 - The 5 patch series "mm: khugepaged cleanups and mTHP prerequisites"
   from Nico Pache provides cleanups in the khugepaged and is a base for
   Nico's planned khugepaged mTHP support.
 
 - The 15 patch series "mm: memory hot(un)plug and SPARSEMEM cleanups"
   from David Hildenbrand implements code movement and cleanups in the
   memhotplug and sparsemem code.
 
 - The 2 patch series "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and
   cleanup CONFIG_MIGRATION" from David Hildenbrand rationalizes some
   memhotplug Kconfig support.
 
 - The 6 patch series "change young flag check functions to return bool"
   from Baolin Wang is "a cleanup patchset to change all young flag check
   functions to return bool".
 
 - The 3 patch series "mm/damon/sysfs: fix memory leak and NULL
   dereference issues" from Josh Law and SeongJae Park fixes a few
   potential DAMON bugs.
 
 - The 25 patch series "mm/vma: convert vm_flags_t to vma_flags_t in vma
   code" from "converts a lot of the existing use of the legacy vm_flags_t
   data type to the new vma_flags_t type which replaces it".  Mainly in the
   vma code.
 
 - The 21 patch series "mm: expand mmap_prepare functionality and usage"
   from Lorenzo Stoakes "expands the mmap_prepare functionality, which is
   intended to replace the deprecated f_op->mmap hook which has been the
   source of bugs and security issues for some time".  Cleanups,
   documentation, extension of mmap_prepare into filesystem drivers.
 
 - The 13 patch series "mm/huge_memory: refactor zap_huge_pmd()" from
   Lorenzo Stoakes simplifies and cleans up zap_huge_pmd().  Additional
   cleanups around vm_normal_folio_pmd() and the softleaf functionality are
   performed.
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Merge tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull MM updates from Andrew Morton:

 - "maple_tree: Replace big node with maple copy" (Liam Howlett)

   Mainly prepararatory work for ongoing development but it does reduce
   stack usage and is an improvement.

 - "mm, swap: swap table phase III: remove swap_map" (Kairui Song)

   Offers memory savings by removing the static swap_map. It also yields
   some CPU savings and implements several cleanups.

 - "mm: memfd_luo: preserve file seals" (Pratyush Yadav)

   File seal preservation to LUO's memfd code

 - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan
   Chen)

   Additional userspace stats reportng to zswap

 - "arch, mm: consolidate empty_zero_page" (Mike Rapoport)

   Some cleanups for our handling of ZERO_PAGE() and zero_pfn

 - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu
   Han)

   A robustness improvement and some cleanups in the kmemleak code

 - "Improve khugepaged scan logic" (Vernon Yang)

   Improve khugepaged scan logic and reduce CPU consumption by
   prioritizing scanning tasks that access memory frequently

 - "Make KHO Stateless" (Jason Miu)

   Simplify Kexec Handover by transitioning KHO from an xarray-based
   metadata tracking system with serialization to a radix tree data
   structure that can be passed directly to the next kernel

 - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas
   Ballasi and Steven Rostedt)

   Enhance vmscan's tracepointing

 - "mm: arch/shstk: Common shadow stack mapping helper and
   VM_NOHUGEPAGE" (Catalin Marinas)

   Cleanup for the shadow stack code: remove per-arch code in favour of
   a generic implementation

 - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin)

   Fix a WARN() which can be emitted the KHO restores a vmalloc area

 - "mm: Remove stray references to pagevec" (Tal Zussman)

   Several cleanups, mainly udpating references to "struct pagevec",
   which became folio_batch three years ago

 - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl
   Shutsemau)

   Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail
   pages encode their relationship to the head page

 - "mm/damon/core: improve DAMOS quota efficiency for core layer
   filters" (SeongJae Park)

   Improve two problematic behaviors of DAMOS that makes it less
   efficient when core layer filters are used

 - "mm/damon: strictly respect min_nr_regions" (SeongJae Park)

   Improve DAMON usability by extending the treatment of the
   min_nr_regions user-settable parameter

 - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka)

   The proper fix for a previously hotfixed SMP=n issue. Code
   simplifications and cleanups ensued

 - "mm: cleanups around unmapping / zapping" (David Hildenbrand)

   A bunch of cleanups around unmapping and zapping. Mostly
   simplifications, code movements, documentation and renaming of
   zapping functions

 - "support batched checking of the young flag for MGLRU" (Baolin Wang)

   Batched checking of the young flag for MGLRU. It's part cleanups; one
   benchmark shows large performance benefits for arm64

 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner)

   memcg cleanup and robustness improvements

 - "Allow order zero pages in page reporting" (Yuvraj Sakshith)

   Enhance free page reporting - it is presently and undesirably order-0
   pages when reporting free memory.

 - "mm: vma flag tweaks" (Lorenzo Stoakes)

   Cleanup work following from the recent conversion of the VMA flags to
   a bitmap

 - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae
   Park)

   Add some more developer-facing debug checks into DAMON core

 - "mm/damon: test and document power-of-2 min_region_sz requirement"
   (SeongJae Park)

   An additional DAMON kunit test and makes some adjustments to the
   addr_unit parameter handling

 - "mm/damon/core: make passed_sample_intervals comparisons
   overflow-safe" (SeongJae Park)

   Fix a hard-to-hit time overflow issue in DAMON core

 - "mm/damon: improve/fixup/update ratio calculation, test and
   documentation" (SeongJae Park)

   A batch of misc/minor improvements and fixups for DAMON

 - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David
   Hildenbrand)

   Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code
   movement was required.

 - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky)

   A somewhat random mix of fixups, recompression cleanups and
   improvements in the zram code

 - "mm/damon: support multiple goal-based quota tuning algorithms"
   (SeongJae Park)

   Extend DAMOS quotas goal auto-tuning to support multiple tuning
   algorithms that users can select

 - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao)

   Fix the khugpaged sysfs handling so we no longer spam the logs with
   reams of junk when starting/stopping khugepaged

 - "mm: improve map count checks" (Lorenzo Stoakes)

   Provide some cleanups and slight fixes in the mremap, mmap and vma
   code

 - "mm/damon: support addr_unit on default monitoring targets for
   modules" (SeongJae Park)

   Extend the use of DAMON core's addr_unit tunable

 - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache)

   Cleanups to khugepaged and is a base for Nico's planned khugepaged
   mTHP support

 - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand)

   Code movement and cleanups in the memhotplug and sparsemem code

 - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup
   CONFIG_MIGRATION" (David Hildenbrand)

   Rationalize some memhotplug Kconfig support

 - "change young flag check functions to return bool" (Baolin Wang)

   Cleanups to change all young flag check functions to return bool

 - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh
   Law and SeongJae Park)

   Fix a few potential DAMON bugs

 - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo
   Stoakes)

   Convert a lot of the existing use of the legacy vm_flags_t data type
   to the new vma_flags_t type which replaces it. Mainly in the vma
   code.

 - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes)

   Expand the mmap_prepare functionality, which is intended to replace
   the deprecated f_op->mmap hook which has been the source of bugs and
   security issues for some time. Cleanups, documentation, extension of
   mmap_prepare into filesystem drivers

 - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes)

   Simplify and clean up zap_huge_pmd(). Additional cleanups around
   vm_normal_folio_pmd() and the softleaf functionality are performed.

* tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
  mm: fix deferred split queue races during migration
  mm/khugepaged: fix issue with tracking lock
  mm/huge_memory: add and use has_deposited_pgtable()
  mm/huge_memory: add and use normal_or_softleaf_folio_pmd()
  mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio()
  mm/huge_memory: separate out the folio part of zap_huge_pmd()
  mm/huge_memory: use mm instead of tlb->mm
  mm/huge_memory: remove unnecessary sanity checks
  mm/huge_memory: deduplicate zap deposited table call
  mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE()
  mm/huge_memory: add a common exit path to zap_huge_pmd()
  mm/huge_memory: handle buggy PMD entry in zap_huge_pmd()
  mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc
  mm/huge: avoid big else branch in zap_huge_pmd()
  mm/huge_memory: simplify vma_is_specal_huge()
  mm: on remap assert that input range within the proposed VMA
  mm: add mmap_action_map_kernel_pages[_full]()
  uio: replace deprecated mmap hook with mmap_prepare in uio_info
  drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare
  mm: allow handling of stacked mmap_prepare hooks in more drivers
  ...
2026-04-15 12:59:16 -07:00
Tal Zussman
4e1d77a8f3 folio_batch: rename pagevec.h to folio_batch.h
struct pagevec was removed in commit 1e0877d58b ("mm: remove struct
pagevec").  Rename include/linux/pagevec.h to reflect reality and update
includes tree-wide.  Add the new filename to MAINTAINERS explicitly, as it
no longer matches the "include/linux/page[-_]*" pattern in MEMORY
MANAGEMENT - CORE.

Link: https://lkml.kernel.org/r/20260225-pagevec_cleanup-v2-3-716868cc2d11@columbia.edu
Signed-off-by: Tal Zussman <tz2294@columbia.edu>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05 13:53:07 -07:00
Jeff Layton
0b2600f81c
treewide: change inode->i_ino from unsigned long to u64
On 32-bit architectures, unsigned long is only 32 bits wide, which
causes 64-bit inode numbers to be silently truncated. Several
filesystems (NFS, XFS, BTRFS, etc.) can generate inode numbers that
exceed 32 bits, and this truncation can lead to inode number collisions
and other subtle bugs on 32-bit systems.

Change the type of inode->i_ino from unsigned long to u64 to ensure that
inode numbers are always represented as 64-bit values regardless of
architecture. Update all format specifiers treewide from %lu/%lx to
%llu/%llx to match the new type, along with corresponding local variable
types.

This is the bulk treewide conversion. Earlier patches in this series
handled trace events separately to allow trace field reordering for
better struct packing on 32-bit.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20260304-iino-u64-v3-12-2257ad83d372@kernel.org
Acked-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-06 14:31:28 +01:00
Linus Torvalds
bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook
69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Edward Adam Davis
9a6b60cb14 nilfs2: avoid having an active sc_timer before freeing sci
Because kthread_stop did not stop sc_task properly and returned -EINTR,
the sc_timer was not properly closed, ultimately causing the problem [1]
reported by syzbot when freeing sci due to the sc_timer not being closed.

Because the thread sc_task main function nilfs_segctor_thread() returns 0
when it succeeds, when the return value of kthread_stop() is not 0 in
nilfs_segctor_destroy(), we believe that it has not properly closed
sc_timer.

We use timer_shutdown_sync() to sync wait for sc_timer to shutdown, and
set the value of sc_task to NULL under the protection of lock
sc_state_lock, so as to avoid the issue caused by sc_timer not being
properly shutdowned.

[1]
ODEBUG: free active (active state 0) object: 00000000dacb411a object type: timer_list hint: nilfs_construction_timeout
Call trace:
 nilfs_segctor_destroy fs/nilfs2/segment.c:2811 [inline]
 nilfs_detach_log_writer+0x668/0x8cc fs/nilfs2/segment.c:2877
 nilfs_put_super+0x4c/0x12c fs/nilfs2/super.c:509

Link: https://lkml.kernel.org/r/20251029225226.16044-1-konishi.ryusuke@gmail.com
Fixes: 3f66cc261c ("nilfs2: use kthread_create and kthread_stop for the log writer thread")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+24d8b70f039151f65590@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=24d8b70f039151f65590
Tested-by: syzbot+24d8b70f039151f65590@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Cc: <stable@vger.kernel.org>	[6.12+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-09 21:19:46 -08:00
Ingo Molnar
41cb08555c treewide, timers: Rename from_timer() to timer_container_of()
Move this API to the canonical timer_*() namespace.

[ tglx: Redone against pre rc1 ]

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com
2025-06-08 09:07:37 +02:00
Christoph Hellwig
84e437640b nilfs2: remove wbc->for_reclaim handling
Since commit 013a07052a ("nilfs2: convert metadata aops from writepage
to writepages"), nilfs_mdt_write_folio can't be called from reclaim
context any more.  Remove the code keyed of the wbc->for_reclaim flag,
which is now only set for writing out swap or shmem pages inside the swap
code, but never passed to file systems.

Link: https://lkml.kernel.org/r/20250508054938.15894-7-hch@lst.de
Link: https://lkml.kernel.org/r/20250516123417.6779-1-konishi.ryusuke@gmail.com
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-05-21 10:48:23 -07:00
Thomas Gleixner
8fa7292fee treewide: Switch/rename to timer_delete[_sync]()
timer_delete[_sync]() replaces del_timer[_sync](). Convert the whole tree
over and remove the historical wrapper inlines.

Conversion was done with coccinelle plus manual fixups where necessary.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-04-05 10:30:12 +02:00
Ryusuke Konishi
2e62857f13 nilfs2: revise the return value description style for consistency.
Also for comments that do not cause kernel-doc warnings (those that list
multiple error codes), revise the return value description style to match
Brian G.'s suggestion of "..., or one of the following negative error
codes on failure:".

Link: https://lkml.kernel.org/r/CAAq45aNh1qV8P6XgDhKeNstT=PvcPUaCXsAF-f9rvmzznsZL5A@mail.gmail.com
Link: https://lkml.kernel.org/r/20250110010530.21872-8-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: "Brian G ." <gissf1@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-24 22:47:25 -08:00
Ryusuke Konishi
fd4e7fadfd nilfs2: add missing return value kernel-doc descriptions
There are a number of kernel-doc comments for functions that are missing
return values, which also causes a number of warnings when the kernel-doc
script is run with the "-Wall" option.

Fix this issue by adding proper return value descriptions, and improve
code maintainability.

Link: https://lkml.kernel.org/r/20250110010530.21872-7-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: "Brian G ." <gissf1@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-24 22:47:25 -08:00
Ryusuke Konishi
343d4a33f2 nilfs2: correct return value kernel-doc descriptions for the rest
Similar to the previous changes to fix return value descriptions, this
fixes the format of the return value descriptions of functions for the
rest.

Link: https://lkml.kernel.org/r/20250110010530.21872-6-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: "Brian G ." <gissf1@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-24 22:47:25 -08:00
Ryusuke Konishi
367a9bffab nilfs2: protect access to buffers with no active references
nilfs_lookup_dirty_data_buffers(), which iterates through the buffers
attached to dirty data folios/pages, accesses the attached buffers without
locking the folios/pages.

For data cache, nilfs_clear_folio_dirty() may be called asynchronously
when the file system degenerates to read only, so
nilfs_lookup_dirty_data_buffers() still has the potential to cause use
after free issues when buffers lose the protection of their dirty state
midway due to this asynchronous clearing and are unintentionally freed by
try_to_free_buffers().

Eliminate this race issue by adjusting the lock section in this function.

Link: https://lkml.kernel.org/r/20250107200202.6432-3-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Fixes: 8c26c4e269 ("nilfs2: fix issue with flush kernel thread after remount in RO mode because of driver's internal error or metadata corruption")
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-01-24 22:47:24 -08:00
Linus Torvalds
7856a56541 Many singleton patches - please see the various changelogs for details.
Quite a lot of nilfs2 work this time around.
 
 Notable patch series in this pull request are:
 
 "mul_u64_u64_div_u64: new implementation" by Nicolas Pitre, with
 assistance from Uwe Kleine-König.  Reimplement mul_u64_u64_div_u64() to
 provide (much) more accurate results.  The current implementation was
 causing Uwe some issues in the PWM drivers.
 
 "xz: Updates to license, filters, and compression options" from Lasse
 Collin.  Miscellaneous maintenance and kinor feature work to the xz
 decompressor.
 
 "Fix some GDB command error and add some GDB commands" from Kuan-Ying Lee.
 Fixes and enhancements to the gdb scripts.
 
 "treewide: add missing MODULE_DESCRIPTION() macros" from Jeff Johnson.
 Adds lots of MODULE_DESCRIPTIONs, thus fixing lots of warnings about this.
 
 "nilfs2: add support for some common ioctls" from Ryusuke Konishi.  Adds
 various commonly-available ioctls to nilfs2.
 
 "This series fixes a number of formatting issues in kernel doc comments"
 from Ryusuke Konishi does that.
 
 "nilfs2: prevent unexpected ENOENT propagation" from Ryusuke Konishi.  Fix
 issues where -ENOENT was being unintentionally and inappropriately
 returned to userspace.
 
 "nilfs2: assorted cleanups" from Huang Xiaojia.
 
 "nilfs2: fix potential issues with empty b-tree nodes" from Ryusuke
 Konishi fixes some issues which can occur on corrupted nilfs2 filesystems.
 
 "scripts/decode_stacktrace.sh: improve error reporting and usability" from
 Luca Ceresoli does those things.
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Merge tag 'mm-nonmm-stable-2024-09-21-07-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull non-MM updates from Andrew Morton:
 "Many singleton patches - please see the various changelogs for
  details.

  Quite a lot of nilfs2 work this time around.

  Notable patch series in this pull request are:

   - "mul_u64_u64_div_u64: new implementation" by Nicolas Pitre, with
     assistance from Uwe Kleine-König. Reimplement mul_u64_u64_div_u64()
     to provide (much) more accurate results. The current implementation
     was causing Uwe some issues in the PWM drivers.

   - "xz: Updates to license, filters, and compression options" from
     Lasse Collin. Miscellaneous maintenance and kinor feature work to
     the xz decompressor.

   - "Fix some GDB command error and add some GDB commands" from
     Kuan-Ying Lee. Fixes and enhancements to the gdb scripts.

   - "treewide: add missing MODULE_DESCRIPTION() macros" from Jeff
     Johnson. Adds lots of MODULE_DESCRIPTIONs, thus fixing lots of
     warnings about this.

   - "nilfs2: add support for some common ioctls" from Ryusuke Konishi.
     Adds various commonly-available ioctls to nilfs2.

   - "This series fixes a number of formatting issues in kernel doc
     comments" from Ryusuke Konishi does that.

   - "nilfs2: prevent unexpected ENOENT propagation" from Ryusuke
     Konishi. Fix issues where -ENOENT was being unintentionally and
     inappropriately returned to userspace.

   - "nilfs2: assorted cleanups" from Huang Xiaojia.

   - "nilfs2: fix potential issues with empty b-tree nodes" from Ryusuke
     Konishi fixes some issues which can occur on corrupted nilfs2
     filesystems.

   - "scripts/decode_stacktrace.sh: improve error reporting and
     usability" from Luca Ceresoli does those things"

* tag 'mm-nonmm-stable-2024-09-21-07-52' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (103 commits)
  list: test: increase coverage of list_test_list_replace*()
  list: test: fix tests for list_cut_position()
  proc: use __auto_type more
  treewide: correct the typo 'retun'
  ocfs2: cleanup return value and mlog in ocfs2_global_read_info()
  nilfs2: remove duplicate 'unlikely()' usage
  nilfs2: fix potential oob read in nilfs_btree_check_delete()
  nilfs2: determine empty node blocks as corrupted
  nilfs2: fix potential null-ptr-deref in nilfs_btree_insert()
  user_namespace: use kmemdup_array() instead of kmemdup() for multiple allocation
  tools/mm: rm thp_swap_allocator_test when make clean
  squashfs: fix percpu address space issues in decompressor_multi_percpu.c
  lib: glob.c: added null check for character class
  nilfs2: refactor nilfs_segctor_thread()
  nilfs2: use kthread_create and kthread_stop for the log writer thread
  nilfs2: remove sc_timer_task
  nilfs2: do not repair reserved inode bitmap in nilfs_new_inode()
  nilfs2: eliminate the shared counter and spinlock for i_generation
  nilfs2: separate inode type information from i_state field
  nilfs2: use the BITS_PER_LONG macro
  ...
2024-09-21 08:20:50 -07:00
Ryusuke Konishi
74b0099340 nilfs2: refactor nilfs_segctor_thread()
Simplify nilfs_segctor_thread(), the main loop function of the log writer
thread, to make the basic structure easier to understand.

In particular, the acquisition and release of the sc_state_lock spinlock
was scattered throughout the function, so extract the determination of
whether log writing is required into a helper function and make the
spinlock lock sections clearer.

Link: https://lkml.kernel.org/r/20240826174116.5008-9-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Huang Xiaojia <huangxiaojia2@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01 20:43:44 -07:00
Ryusuke Konishi
3f66cc261c nilfs2: use kthread_create and kthread_stop for the log writer thread
By using kthread_create() and kthread_stop() to start and stop the log
writer thread, eliminate custom thread start and stop helpers, as well as
the wait queue "sc_wait_task" on the "nilfs_sc_info" struct and
NILFS_SEGCTOR_QUIT flag that exist only to implement them.

Also, update the kernel doc comments of the changed functions as
appropriate.

Link: https://lkml.kernel.org/r/20240826174116.5008-8-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Huang Xiaojia <huangxiaojia2@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01 20:43:44 -07:00
Ryusuke Konishi
cfdfe9e17c nilfs2: remove sc_timer_task
After commit f5d4e04634 ("nilfs2: fix use-after-free of timer for log
writer thread") is applied, nilfs_construct_timeout(), which is called by
a timer and wakes up the log writer thread, is never called after the log
writer thread has terminated.

As a result, the member variable "sc_timer_task" of the "nilfs_sc_info"
structure, which was added when timer_setup() was adopted to retain a
reference to the log writer thread's task even after it had terminated, is
no longer needed, as it should be; we can simply use "sc_task" instead,
which holds a reference to the log writer thread's task for its lifetime. 
So, eliminate "sc_timer_task" by this means.

Link: https://lkml.kernel.org/r/20240826174116.5008-7-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Huang Xiaojia <huangxiaojia2@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01 20:43:43 -07:00
Ryusuke Konishi
d7cee0b342 nilfs2: separate inode type information from i_state field
In nilfs_iget_locked() and nilfs_ilookup(), which are used to find or
obtain nilfs2 inodes, the nilfs_iget_args structure used to identify
inodes has type information divided into multiple booleans, making type
determination complicated.

Simplify inode type determination by consolidating inode type information
into an unsigned integer represented by a comibination of flags and by
separating the type identification information for on-memory inodes from
the i_state member in the nilfs_inode_info structure.

Link: https://lkml.kernel.org/r/20240826174116.5008-4-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Huang Xiaojia <huangxiaojia2@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01 20:43:43 -07:00
Ryusuke Konishi
0b9aad46c1 nilfs2: do not propagate ENOENT error from sufile during GC
nilfs_sufile_freev(), which is used to free segments in GC, aborts with
-ENOENT if the target segment usage is on a hole block.

This error only occurs if one of the segment numbers to be freed passed by
the GC ioctl is invalid, so return -EINVAL instead.

To avoid impairing readability, introduce a wrapper function that
encapsulates error handling including the error code conversion (and error
message output).

Link: https://lkml.kernel.org/r/20240821154627.11848-5-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01 20:43:39 -07:00
Ryusuke Konishi
6576dd6695 nilfs2: fix state management in error path of log writing function
After commit a694291a62 ("nilfs2: separate wait function from
nilfs_segctor_write") was applied, the log writing function
nilfs_segctor_do_construct() was able to issue I/O requests continuously
even if user data blocks were split into multiple logs across segments,
but two potential flaws were introduced in its error handling.

First, if nilfs_segctor_begin_construction() fails while creating the
second or subsequent logs, the log writing function returns without
calling nilfs_segctor_abort_construction(), so the writeback flag set on
pages/folios will remain uncleared.  This causes page cache operations to
hang waiting for the writeback flag.  For example,
truncate_inode_pages_final(), which is called via nilfs_evict_inode() when
an inode is evicted from memory, will hang.

Second, the NILFS_I_COLLECTED flag set on normal inodes remain uncleared. 
As a result, if the next log write involves checkpoint creation, that's
fine, but if a partial log write is performed that does not, inodes with
NILFS_I_COLLECTED set are erroneously removed from the "sc_dirty_files"
list, and their data and b-tree blocks may not be written to the device,
corrupting the block mapping.

Fix these issues by uniformly calling nilfs_segctor_abort_construction()
on failure of each step in the loop in nilfs_segctor_do_construct(),
having it clean up logs and segment usages according to progress, and
correcting the conditions for calling nilfs_redirty_inodes() to ensure
that the NILFS_I_COLLECTED flag is cleared.

Link: https://lkml.kernel.org/r/20240814101119.4070-1-konishi.ryusuke@gmail.com
Fixes: a694291a62 ("nilfs2: separate wait function from nilfs_segctor_write")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01 17:59:00 -07:00
Ryusuke Konishi
0f3819e8c4 nilfs2: avoid undefined behavior in nilfs_cnt32_ge macro
According to the C standard 3.4.3p3, the result of signed integer overflow
is undefined.  The macro nilfs_cnt32_ge(), which compares two sequence
numbers, uses signed integer subtraction that can overflow, and therefore
the result of the calculation may differ from what is expected due to
undefined behavior in different environments.

Similar to an earlier change to the jiffies-related comparison macros in
commit 5a581b367b ("jiffies: Avoid undefined behavior from signed
overflow"), avoid this potential issue by changing the definition of the
macro to perform the subtraction as unsigned integers, then cast the
result to a signed integer for comparison.

Link: https://lkml.kernel.org/r/20130727225828.GA11864@linux.vnet.ibm.com
Link: https://lkml.kernel.org/r/20240702183512.6390-1-konishi.ryusuke@gmail.com
Fixes: 9ff05123e3 ("nilfs2: segment constructor")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-04 23:43:11 -07:00
Ryusuke Konishi
68142cb628 nilfs2: do not call inode_attach_wb() directly
Call mark_buffer_dirty() for segment summary and super root block buffers
on the backing device's page cache, thereby indirectly calling
inode_attach_wb().

Then remove the no longer needed call to inode_attach_wb() in
nilfs_attach_log_writer(), resolving the concern about its layer-violating
use.

Link: https://lkml.kernel.org/r/20240610160029.7673-3-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:25:09 -07:00
Ryusuke Konishi
25fa5f9923 nilfs2: prepare backing device folios for writing after adding checksums
Patch series "nilfs2: eliminate the call to inode_attach_wb()".

This series eliminates the inode_attach_wb() call from nilfs2, which was
introduced as a workaround for a kernel bug but is suspected of layer
violation (in fact, it is undesirable since it exposes a reference to the
backing device).

Removal of the inode_attach_wb() call is done by simply using
mark_buffer_dirty() on the backing device's buffers.  To use it safely,
this series will prepare it in patch 1/2, and perform the replacement
itself in patch 2/2.


This patch (of 2):

In preparation for inode_attach_wb(), which is currently called when
attaching the log writer, to be done via mark_buffer_dirty(), change the
order of preparation for log writing.

Specifically, the function call that adds checksums to segment summary and
super root blocks, which correspond to the log header and trailer, is made
before starting writeback of folios containing those blocks.

The current steps are as follows:

1. Put the folios of segment summary blocks in writeback state.
2. Put the folios of data blocks, metadata file blocks, and btree node
   blocks (collectively called payload blocks) into writeback state.
3. Put the super root block folio in writeback state.
4. Add checksums.

Change these as follows:

1. Put the folios of payload blocks in writeback state.
2. Add checksums.
3. Put the folios of segment summary blocks in writeback state.
4. Put the super root block folio in writeback state.

In this order, the contents of segment summaries and super root block
that directly use buffer/folio of the backing device can be determined
including the addition of checksums, before preparing to write.

Step (1), which puts the payload block folios in writeback state, is
performed first because if there are memory-mapped data blocks, a valid
checksum can only be calculated after step (1).

Link: https://lkml.kernel.org/r/20240610160029.7673-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-24 22:25:09 -07:00
Ryusuke Konishi
a4ca369ca2 nilfs2: fix potential kernel bug due to lack of writeback flag waiting
Destructive writes to a block device on which nilfs2 is mounted can cause
a kernel bug in the folio/page writeback start routine or writeback end
routine (__folio_start_writeback in the log below):

 kernel BUG at mm/page-writeback.c:3070!
 Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
 ...
 RIP: 0010:__folio_start_writeback+0xbaa/0x10e0
 Code: 25 ff 0f 00 00 0f 84 18 01 00 00 e8 40 ca c6 ff e9 17 f6 ff ff
  e8 36 ca c6 ff 4c 89 f7 48 c7 c6 80 c0 12 84 e8 e7 b3 0f 00 90 <0f>
  0b e8 1f ca c6 ff 4c 89 f7 48 c7 c6 a0 c6 12 84 e8 d0 b3 0f 00
 ...
 Call Trace:
  <TASK>
  nilfs_segctor_do_construct+0x4654/0x69d0 [nilfs2]
  nilfs_segctor_construct+0x181/0x6b0 [nilfs2]
  nilfs_segctor_thread+0x548/0x11c0 [nilfs2]
  kthread+0x2f0/0x390
  ret_from_fork+0x4b/0x80
  ret_from_fork_asm+0x1a/0x30
  </TASK>

This is because when the log writer starts a writeback for segment summary
blocks or a super root block that use the backing device's page cache, it
does not wait for the ongoing folio/page writeback, resulting in an
inconsistent writeback state.

Fix this issue by waiting for ongoing writebacks when putting
folios/pages on the backing device into writeback state.

Link: https://lkml.kernel.org/r/20240530141556.4411-1-konishi.ryusuke@gmail.com
Fixes: 9ff05123e3 ("nilfs2: segment constructor")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-06-05 19:19:24 -07:00
Ryusuke Konishi
eb85dace89 nilfs2: fix potential hang in nilfs_detach_log_writer()
Syzbot has reported a potential hang in nilfs_detach_log_writer() called
during nilfs2 unmount.

Analysis revealed that this is because nilfs_segctor_sync(), which
synchronizes with the log writer thread, can be called after
nilfs_segctor_destroy() terminates that thread, as shown in the call trace
below:

nilfs_detach_log_writer
  nilfs_segctor_destroy
    nilfs_segctor_kill_thread  --> Shut down log writer thread
    flush_work
      nilfs_iput_work_func
        nilfs_dispose_list
          iput
            nilfs_evict_inode
              nilfs_transaction_commit
                nilfs_construct_segment (if inode needs sync)
                  nilfs_segctor_sync  --> Attempt to synchronize with
                                          log writer thread
                           *** DEADLOCK ***

Fix this issue by changing nilfs_segctor_sync() so that the log writer
thread returns normally without synchronizing after it terminates, and by
forcing tasks that are already waiting to complete once after the thread
terminates.

The skipped inode metadata flushout will then be processed together in the
subsequent cleanup work in nilfs_segctor_destroy().

Link: https://lkml.kernel.org/r/20240520132621.4054-4-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+e3973c409251e136fdd0@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=e3973c409251e136fdd0
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Cc: "Bai, Shuangpeng" <sjb7183@psu.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-24 11:55:07 -07:00
Ryusuke Konishi
936184eadd nilfs2: fix unexpected freezing of nilfs_segctor_sync()
A potential and reproducible race issue has been identified where
nilfs_segctor_sync() would block even after the log writer thread writes a
checkpoint, unless there is an interrupt or other trigger to resume log
writing.

This turned out to be because, depending on the execution timing of the
log writer thread running in parallel, the log writer thread may skip
responding to nilfs_segctor_sync(), which causes a call to schedule()
waiting for completion within nilfs_segctor_sync() to lose the opportunity
to wake up.

The reason why waking up the task waiting in nilfs_segctor_sync() may be
skipped is that updating the request generation issued using a shared
sequence counter and adding an wait queue entry to the request wait queue
to the log writer, are not done atomically.  There is a possibility that
log writing and request completion notification by nilfs_segctor_wakeup()
may occur between the two operations, and in that case, the wait queue
entry is not yet visible to nilfs_segctor_wakeup() and the wake-up of
nilfs_segctor_sync() will be carried over until the next request occurs.

Fix this issue by performing these two operations simultaneously within
the lock section of sc_state_lock.  Also, following the memory barrier
guidelines for event waiting loops, move the call to set_current_state()
in the same location into the event waiting loop to ensure that a memory
barrier is inserted just before the event condition determination.

Link: https://lkml.kernel.org/r/20240520132621.4054-3-konishi.ryusuke@gmail.com
Fixes: 9ff05123e3 ("nilfs2: segment constructor")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Cc: "Bai, Shuangpeng" <sjb7183@psu.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-24 11:55:07 -07:00
Ryusuke Konishi
f5d4e04634 nilfs2: fix use-after-free of timer for log writer thread
Patch series "nilfs2: fix log writer related issues".

This bug fix series covers three nilfs2 log writer-related issues,
including a timer use-after-free issue and potential deadlock issue on
unmount, and a potential freeze issue in event synchronization found
during their analysis.  Details are described in each commit log.


This patch (of 3):

A use-after-free issue has been reported regarding the timer sc_timer on
the nilfs_sc_info structure.

The problem is that even though it is used to wake up a sleeping log
writer thread, sc_timer is not shut down until the nilfs_sc_info structure
is about to be freed, and is used regardless of the thread's lifetime.

Fix this issue by limiting the use of sc_timer only while the log writer
thread is alive.

Link: https://lkml.kernel.org/r/20240520132621.4054-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20240520132621.4054-2-konishi.ryusuke@gmail.com
Fixes: fdce895ea5 ("nilfs2: change sc_timer from a pointer to an embedded one in struct nilfs_sc_info")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: "Bai, Shuangpeng" <sjb7183@psu.edu>
Closes: https://groups.google.com/g/syzkaller/c/MK_LYqtt8ko/m/8rgdWeseAwAJ
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-24 11:55:07 -07:00
Linus Torvalds
38da32ee70 bd_inode series
Replacement of bdev->bd_inode with sane(r) set of primitives.
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Merge tag 'pull-bd_inode-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull bdev bd_inode updates from Al Viro:
 "Replacement of bdev->bd_inode with sane(r) set of primitives by me and
  Yu Kuai"

* tag 'pull-bd_inode-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  RIP ->bd_inode
  dasd_format(): killing the last remaining user of ->bd_inode
  nilfs_attach_log_writer(): use ->bd_mapping->host instead of ->bd_inode
  block/bdev.c: use the knowledge of inode/bdev coallocation
  gfs2: more obvious initializations of mapping->host
  fs/buffer.c: massage the remaining users of ->bd_inode to ->bd_mapping
  blk_ioctl_{discard,zeroout}(): we only want ->bd_inode->i_mapping here...
  grow_dev_folio(): we only want ->bd_inode->i_mapping there
  use ->bd_mapping instead of ->bd_inode->i_mapping
  block_device: add a pointer to struct address_space (page cache of bdev)
  missing helpers: bdev_unhash(), bdev_drop()
  block: move two helpers into bdev.c
  block2mtd: prevent direct access of bd_inode
  dm-vdo: use bdev_nr_bytes(bdev) instead of i_size_read(bdev->bd_inode)
  blkdev_write_iter(): saner way to get inode and bdev
  bcachefs: remove dead function bdev_sectors()
  ext4: remove block_device_ejected()
  erofs_buf: store address_space instead of inode
  erofs: switch erofs_bread() to passing offset instead of block number
2024-05-21 09:51:42 -07:00
Matthew Wilcox (Oracle)
a7ac59f4f2 nilfs2: remove calls to folio_set_error() and folio_clear_error()
Nobody checks this flag on nilfs2 folios, stop setting and clearing it. 
That lets us simplify nilfs_end_folio_io() slightly.

Link: https://lkml.kernel.org/r/20240420025029.2166544-17-willy@infradead.org
Link: https://lkml.kernel.org/r/20240430050901.3239-1-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <song@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-11 15:51:43 -07:00
Al Viro
3386183382 nilfs_attach_log_writer(): use ->bd_mapping->host instead of ->bd_inode
I suspect that inode_attach_wb() use is rather unidiomatic, but
that's a separate story - in any case, its use is a few times
per mount *and* the route by which we access that inode is
"the host of address_space a page belongs to".

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2024-05-03 02:36:55 -04:00
Ryusuke Konishi
cce259b4c3 nilfs2: localize highmem mapping for checkpoint finalization within cpfile
Move the checkpoint finalization routine to the cpfile side, and make the
page mapping local and temporary.  And use kmap_local instead of kmap to
access the checkpoint entry page when finalizing a checkpoint.

In this conversion, some of the information on the checkpoint entry being
rewritten is passed through the arguments of the newly added method
nilfs_cpfile_finalize_checkpoint().

Link: https://lkml.kernel.org/r/20240122140202.6950-13-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 15:38:53 -08:00
Ryusuke Konishi
d37db936c5 nilfs2: localize highmem mapping for checkpoint creation within cpfile
In order to convert kmap() used in cpfile to kmap_local, first move the
checkpoint creation routine, which is one of the places where kmap is
used, to the cpfile side and make the page mapping local and temporary. 
And use kmap_local instead of kmap to access the checkpoint entry page
(and header block page) when generating a checkpoint.

Link: https://lkml.kernel.org/r/20240122140202.6950-12-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 15:38:53 -08:00
Ryusuke Konishi
7282f2ae81 nilfs2: convert ifile to use kmap_local
Convert deprecated kmap() and kmap_atomic() to use kmap_local for the
ifile metadata file used to manage disk inodes.

In some usages, calls to kmap_local and kunmap_local are split into
different helpers, but those usages can be safely changed to local thread
kmap.

Link: https://lkml.kernel.org/r/20240122140202.6950-11-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 15:38:53 -08:00
Ryusuke Konishi
9cced6a521 nilfs2: move nilfs_bmap_write call out of nilfs_write_inode_common
Before converting the disk inode management metadata file ifile, the call
to nilfs_bmap_write(), the i_device_code setting, and the zero-fill code
for inodes on the super root block are moved from
nilfs_write_inode_common() to its callers.

This cleanup simplifies the role and arguments of
nilfs_write_inode_common() and collects calls to nilfs_bmap_write() to the
log writing code.

Also, add and use a new helper nilfs_write_root_mdt_inode() to avoid code
duplication in the data export routine nilfs_segctor_fill_in_super_root()
to the super root block's buffer.

Link: https://lkml.kernel.org/r/20240122140202.6950-9-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-22 15:38:53 -08:00
Ryusuke Konishi
5bc09b397c nilfs2: fix potential bug in end_buffer_async_write
According to a syzbot report, end_buffer_async_write(), which handles the
completion of block device writes, may detect abnormal condition of the
buffer async_write flag and cause a BUG_ON failure when using nilfs2.

Nilfs2 itself does not use end_buffer_async_write().  But, the async_write
flag is now used as a marker by commit 7f42ec3941 ("nilfs2: fix issue
with race condition of competition between segments for dirty blocks") as
a means of resolving double list insertion of dirty blocks in
nilfs_lookup_dirty_data_buffers() and nilfs_lookup_node_buffers() and the
resulting crash.

This modification is safe as long as it is used for file data and b-tree
node blocks where the page caches are independent.  However, it was
irrelevant and redundant to also introduce async_write for segment summary
and super root blocks that share buffers with the backing device.  This
led to the possibility that the BUG_ON check in end_buffer_async_write
would fail as described above, if independent writebacks of the backing
device occurred in parallel.

The use of async_write for segment summary buffers has already been
removed in a previous change.

Fix this issue by removing the manipulation of the async_write flag for
the remaining super root block buffer.

Link: https://lkml.kernel.org/r/20240203161645.4992-1-konishi.ryusuke@gmail.com
Fixes: 7f42ec3941 ("nilfs2: fix issue with race condition of competition between segments for dirty blocks")
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+5c04210f7c7f897c1e7f@syzkaller.appspotmail.com
Closes: https://lkml.kernel.org/r/00000000000019a97c05fd42f8c8@google.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-07 21:20:37 -08:00
Kevin Hao
5b130948d5 nilfs2: add missing set_freezable() for freezable kthread
The kernel thread function nilfs_segctor_thread() invokes the
try_to_freeze() in its loop.  But all the kernel threads are non-freezable
by default.  So if we want to make a kernel thread to be freezable, we
have to invoke set_freezable() explicitly.

Link: https://lkml.kernel.org/r/20231219090918.2329-1-konishi.ryusuke@gmail.com
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-29 12:22:28 -08:00
Matthew Wilcox (Oracle)
ff5710c3f3 nilfs2: convert nilfs_segctor_prepare_write to use folios
Use the new folio APIs, saving 17 hidden calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-11-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10 17:21:28 -08:00
Matthew Wilcox (Oracle)
6609e23576 nilfs2: convert to __nilfs_clear_folio_dirty()
All callers now have a folio, so convert to pass a folio.  No caller uses
the return value, so make it return void.  Removes a couple of hidden
calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-10-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10 17:21:28 -08:00
Matthew Wilcox (Oracle)
36319c0c1c nilfs2: convert to nilfs_folio_buffers_clean()
All callers of nilfs_page_buffers_clean() now have a folio, so convert it
to take a folio.  While I'm at it, make it return a bool.

Link: https://lkml.kernel.org/r/20231114084436.2755-6-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10 17:21:27 -08:00
Matthew Wilcox (Oracle)
3cd36212bf nilfs2: convert nilfs_segctor_complete_write to use folios
Use the new folio APIs, saving five calls to compound_head().  This
includes the last callers of nilfs_end_page_io(), so remove that too.

Link: https://lkml.kernel.org/r/20231114084436.2755-4-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10 17:21:26 -08:00
Matthew Wilcox (Oracle)
50196f0081 nilfs2: convert nilfs_abort_logs to use folios
Use the new folio APIs, saving five hidden calls to compound_head().

Link: https://lkml.kernel.org/r/20231114084436.2755-3-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10 17:21:26 -08:00
Matthew Wilcox (Oracle)
8f46eaf6fd nilfs2: add nilfs_end_folio_io()
Patch series "nilfs2: Folio conversions for file paths".

This series advances page->folio conversions for a wide range of nilfs2,
including its file operations, block routines, and the log writer's
writeback routines.  It doesn't cover large folios support, but it saves a
lot of hidden compound_head() calls while preserving the existing support
range behavior.

The original series in post [1] also covered directory-related page->folio
conversions, but that was put on hold because a regression was found in
testing, so this is an excerpt from the first half of the original post.

[1] https://lkml.kernel.org/r/20231106173903.1734114-1-willy@infradead.org

I tested this series in both 32-bit and 64-bit environments, switching
between normal and small block sizes.  I also reviewed all changes in all
patches to ensure they do not break existing behavior.  There were no
problems.


This patch (of 20):

This is the folio counterpart of the existing nilfs_end_page_io() which is
retained as a wrapper of nilfs_end_folio_io().  Replaces nine hidden calls
to compound_head() with one.

Link: https://lkml.kernel.org/r/20231114084436.2755-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20231114084436.2755-2-konishi.ryusuke@gmail.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-12-10 17:21:26 -08:00
Matthew Wilcox (Oracle)
0a88810d9b buffer: remove folio_create_empty_buffers()
With all users converted, remove the old create_empty_buffers() and rename
folio_create_empty_buffers() to create_empty_buffers().

Link: https://lkml.kernel.org/r/20231016201114.1928083-28-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-25 16:47:10 -07:00
Matthew Wilcox (Oracle)
922b12eff0 nilfs2: convert nilfs_lookup_dirty_data_buffers to use folio_create_empty_buffers
This function was already using a folio, so this update to the new API
removes a single folio->page->folio conversion.

Link: https://lkml.kernel.org/r/20231016201114.1928083-17-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-25 16:47:09 -07:00
Ryusuke Konishi
f83913f8c5 nilfs2: fix general protection fault in nilfs_lookup_dirty_data_buffers()
A syzbot stress test reported that create_empty_buffers() called from
nilfs_lookup_dirty_data_buffers() can cause a general protection fault.

Analysis using its reproducer revealed that the back reference "mapping"
from a page/folio has been changed to NULL after dirty page/folio gang
lookup in nilfs_lookup_dirty_data_buffers().

Fix this issue by excluding pages/folios from being collected if, after
acquiring a lock on each page/folio, its back reference "mapping" differs
from the pointer to the address space struct that held the page/folio.

Link: https://lkml.kernel.org/r/20230805132038.6435-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+0ad741797f4565e7e2d2@syzkaller.appspotmail.com
Closes: https://lkml.kernel.org/r/0000000000002930a705fc32b231@google.com
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21 13:07:21 -07:00
Ryusuke Konishi
f8654743a0 nilfs2: fix use-after-free of nilfs_root in dirtying inodes via iput
During unmount process of nilfs2, nothing holds nilfs_root structure after
nilfs2 detaches its writer in nilfs_detach_log_writer().  Previously,
nilfs_evict_inode() could cause use-after-free read for nilfs_root if
inodes are left in "garbage_list" and released by nilfs_dispose_list at
the end of nilfs_detach_log_writer(), and this bug was fixed by commit
9b5a04ac3a ("nilfs2: fix use-after-free bug of nilfs_root in
nilfs_evict_inode()").

However, it turned out that there is another possibility of UAF in the
call path where mark_inode_dirty_sync() is called from iput():

nilfs_detach_log_writer()
  nilfs_dispose_list()
    iput()
      mark_inode_dirty_sync()
        __mark_inode_dirty()
          nilfs_dirty_inode()
            __nilfs_mark_inode_dirty()
              nilfs_load_inode_block() --> causes UAF of nilfs_root struct

This can happen after commit 0ae45f63d4 ("vfs: add support for a
lazytime mount option"), which changed iput() to call
mark_inode_dirty_sync() on its final reference if i_state has I_DIRTY_TIME
flag and i_nlink is non-zero.

This issue appears after commit 28a65b49eb ("nilfs2: do not write dirty
data after degenerating to read-only") when using the syzbot reproducer,
but the issue has potentially existed before.

Fix this issue by adding a "purging flag" to the nilfs structure, setting
that flag while disposing the "garbage_list" and checking it in
__nilfs_mark_inode_dirty().

Unlike commit 9b5a04ac3a ("nilfs2: fix use-after-free bug of nilfs_root
in nilfs_evict_inode()"), this patch does not rely on ns_writer to
determine whether to skip operations, so as not to break recovery on
mount.  The nilfs_salvage_orphan_logs routine dirties the buffer of
salvaged data before attaching the log writer, so changing
__nilfs_mark_inode_dirty() to skip the operation when ns_writer is NULL
will cause recovery write to fail.  The purpose of using the cleanup-only
flag is to allow for narrowing of such conditions.

Link: https://lkml.kernel.org/r/20230728191318.33047-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+74db8b3087f293d3a13a@syzkaller.appspotmail.com
Closes: https://lkml.kernel.org/r/000000000000b4e906060113fd63@google.com
Fixes: 0ae45f63d4 ("vfs: add support for a lazytime mount option")
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org> # 4.0+
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-04 13:03:43 -07:00
Ryusuke Konishi
679bd7ebdd nilfs2: fix buffer corruption due to concurrent device reads
As a result of analysis of a syzbot report, it turned out that in three
cases where nilfs2 allocates block device buffers directly via sb_getblk,
concurrent reads to the device can corrupt the allocated buffers.

Nilfs2 uses sb_getblk for segment summary blocks, that make up a log
header, and the super root block, that is the trailer, and when moving and
writing the second super block after fs resize.

In any of these, since the uptodate flag is not set when storing metadata
to be written in the allocated buffers, the stored metadata will be
overwritten if a device read of the same block occurs concurrently before
the write.  This causes metadata corruption and misbehavior in the log
write itself, causing warnings in nilfs_btree_assign() as reported.

Fix these issues by setting an uptodate flag on the buffer head on the
first or before modifying each buffer obtained with sb_getblk, and
clearing the flag on failure.

When setting the uptodate flag, the lock_buffer/unlock_buffer pair is used
to perform necessary exclusive control, and the buffer is filled to ensure
that uninitialized bytes are not mixed into the data read from others.  As
for buffers for segment summary blocks, they are filled incrementally, so
if the uptodate flag was unset on their allocation, set the flag and zero
fill the buffer once at that point.

Also, regarding the superblock move routine, the starting point of the
memset call to zerofill the block is incorrectly specified, which can
cause a buffer overflow on file systems with block sizes greater than
4KiB.  In addition, if the superblock is moved within a large block, it is
necessary to assume the possibility that the data in the superblock will
be destroyed by zero-filling before copying.  So fix these potential
issues as well.

Link: https://lkml.kernel.org/r/20230609035732.20426-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+31837fe952932efc8fb9@syzkaller.appspotmail.com
Closes: https://lkml.kernel.org/r/00000000000030000a05e981f475@google.com
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-19 13:19:33 -07:00
Ryusuke Konishi
28a65b49eb nilfs2: do not write dirty data after degenerating to read-only
According to syzbot's report, mark_buffer_dirty() called from
nilfs_segctor_do_construct() outputs a warning with some patterns after
nilfs2 detects metadata corruption and degrades to read-only mode.

After such read-only degeneration, page cache data may be cleared through
nilfs_clear_dirty_page() which may also clear the uptodate flag for their
buffer heads.  However, even after the degeneration, log writes are still
performed by unmount processing etc., which causes mark_buffer_dirty() to
be called for buffer heads without the "uptodate" flag and causes the
warning.

Since any writes should not be done to a read-only file system in the
first place, this fixes the warning in mark_buffer_dirty() by letting
nilfs_segctor_do_construct() abort early if in read-only mode.

This also changes the retry check of nilfs_segctor_write_out() to avoid
unnecessary log write retries if it detects -EROFS that
nilfs_segctor_do_construct() returned.

Link: https://lkml.kernel.org/r/20230427011526.13457-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+2af3bc9585be7f23f290@syzkaller.appspotmail.com
  Link: https://syzkaller.appspot.com/bug?extid=2af3bc9585be7f23f290
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-05-06 10:10:07 -07:00
Ryusuke Konishi
ef832747a8 nilfs2: initialize unused bytes in segment summary blocks
Syzbot still reports uninit-value in nilfs_add_checksums_on_logs() for
KMSAN enabled kernels after applying commit 7397031622 ("nilfs2:
initialize "struct nilfs_binfo_dat"->bi_pad field").

This is because the unused bytes at the end of each block in segment
summaries are not initialized.  So this fixes the issue by padding the
unused bytes with null bytes.

Link: https://lkml.kernel.org/r/20230417173513.12598-1-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Tested-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Reported-by: syzbot+048585f3f4227bb2b49b@syzkaller.appspotmail.com
  Link: https://syzkaller.appspot.com/bug?extid=048585f3f4227bb2b49b
Cc: Alexander Potapenko <glider@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-18 14:22:14 -07:00
Ryusuke Konishi
6be49d100c nilfs2: fix potential UAF of struct nilfs_sc_info in nilfs_segctor_thread()
The finalization of nilfs_segctor_thread() can race with
nilfs_segctor_kill_thread() which terminates that thread, potentially
causing a use-after-free BUG as KASAN detected.

At the end of nilfs_segctor_thread(), it assigns NULL to "sc_task" member
of "struct nilfs_sc_info" to indicate the thread has finished, and then
notifies nilfs_segctor_kill_thread() of this using waitqueue
"sc_wait_task" on the struct nilfs_sc_info.

However, here, immediately after the NULL assignment to "sc_task", it is
possible that nilfs_segctor_kill_thread() will detect it and return to
continue the deallocation, freeing the nilfs_sc_info structure before the
thread does the notification.

This fixes the issue by protecting the NULL assignment to "sc_task" and
its notification, with spinlock "sc_state_lock" of the struct
nilfs_sc_info.  Since nilfs_segctor_kill_thread() does a final check to
see if "sc_task" is NULL with "sc_state_lock" locked, this can eliminate
the race.

Link: https://lkml.kernel.org/r/20230327175318.8060-1-konishi.ryusuke@gmail.com
Reported-by: syzbot+b08ebcc22f8f3e6be43a@syzkaller.appspotmail.com
Link: https://lkml.kernel.org/r/00000000000000660d05f7dfa877@google.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-05 18:06:23 -07:00