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4 daysMerge tag 'for-7.2-rc5-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "Zoned mode: - fix assertion and handle case of finished zone and truncated extent - fix zone metadata write pointer on actual zone reset - fix deadlock caused metadata writeback and transaction commit - fix return value reuse leading to confusion about chunk reservations raid56 scrub: - fix tracking of sector checksums when there are not checksums found - fix inverted logic when submitting parity read bio mount/remount fixes: - fix leaking 'remount in progress' state which can break other operations to work (qgroup rescan, autodefrag, reclaim) - adjust using global block reserve after read-only mount when using rescue= option - handle missing raid stripe tree when mounted with 'ignorebadroots' Misc: - fix -Wmaybe-uninitialized warning in GET_CSUMS ioctl" * tag 'for-7.2-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: raid56: fix scrub read assembly submitting no reads btrfs: zoned: skip fully truncated ordered extents at zone finish btrfs: initialize 'args' to avoid compiler warning in btrfs_ioctl_get_csums() btrfs: zoned: fix missing chunk metadata reservation btrfs: raid56: fix an incorrect csum skip during scrub btrfs: report missing raid stripe tree root during lookup btrfs: skip global block reserve accounting for rescue mounts btrfs: zoned: reset meta_write_pointer on zone reset btrfs: zoned: fix deadlock between metadata writeback and transaction commit btrfs: fix leaking BTRFS_FS_STATE_REMOUNTING flag
6 daysMerge tag 'vfs-7.2-rc5.fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs fixes from Christian Brauner: - vfs: Preserve the ACL_DONT_CACHE state in forget_cached_acl(). ACL_DONT_CACHE is meant to be a permanent opt-out from ACL caching which FUSE relies on for servers that don't negotiate FUSE_POSIX_ACL. The helper replaced it with ACL_NOT_CACHED, silently re-enabling the cache, and as fuse doesn't invalidate the cache for such servers a properly timed get_acl() returned stale ACLs. Comes with a fuse selftest reproducing this. - pidfs: - Preserve PIDFD_THREAD when a thread pidfd is reopened via open_by_handle_at(). PIDFD_THREAD shares the O_EXCL bit which do_dentry_open() strips after the flags have been validated, so the reopened pidfd silently became a process pidfd. Comes with a selftest. - Add a pidfs_dentry_open() helper so the regular pidfd allocation path and the file handle path share the code that forces O_RDWR and reapplies the pidfd flags that do_dentry_open() strips. - Handle FS_IOC32_GETVERSION in the compat ioctl path. - Make pidfs_ino_lock static. - iomap: - Fix the block range calculation in ifs_clear_range_dirty() so a partial clear doesn't drop the dirty state of blocks the range only partially covers. - Support invalidating partial folios so a partial truncate or hole punch with blocksize < foliosize doesn't leave stale dirty bits behind. - Only set did_zero when iomap_zero_iter() actually zeroed something. - Guard ifs_set_range_dirty() and ifs_set_range_uptodate() against zero-length ranges where the unsigned last-block calculation underflows and bitmap_set() writes far beyond the ifs->state allocation. - Don't merge ioends with different io_private values as the merge could leak or corrupt the private data of the individual ioends. - exec: - Raise bprm->have_execfd only once the binfmt_misc interpreter has actually been opened. The flag was set as soon as a matching 'O' or 'C' entry was found. If the interpreter open failed with ENOEXEC the exec fell through to the next binary format with have_execfd raised but no executable staged and begin_new_exec() NULL derefed past the point of no return. - Fix an unsigned loop counter wrap in transfer_args_to_stack() on nommu. An overlong argument or environment string pushes bprm->p below PAGE_SIZE, the stop index becomes zero, and the loop never terminates, wrapping its counter and copying garbage from in front of the page array into the new process stack. - Make binfmt_elf_fdpic only honour the first PT_INTERP like binfmt_elf does. Each additional PT_INTERP overwrote the previous interpreter, leaking the name allocation and the interpreter file reference together with the write denial open_exec() took, leaving the file unwritable for as long as the system runs. - overlayfs: - Compare the full escaped xattr prefix including the trailing dot. An xattr like "trusted.overlay.overlayfoo" was misclassified as an escaped overlay xattr. - Check read access to the copy_file_range() source with the source's mounter credentials. - super: Thawing a filesystem whose block device was frozen with bdev_freeze() deadlocked. Dropping the last block layer freeze reference from under s_umount ends up in fs_bdev_thaw() which reacquires s_umount on the same task. Pin the superblock with an active reference instead and call bdev_thaw() without holding s_umount. - procfs: Return EACCES instead of success when the ptrace access check for namespace links fails. - afs: Use afs_dir_get_block() rather than afs_dir_find_block() for block 0 in afs_edit_dir_remove(), matching afs_edit_dir_add(). - Push the memcg gating of ->nr_cached_objects() down into the btrfs and shmem callbacks instead of skipping every callback during non-root memcg reclaim. The blanket check short-circuited XFS whose inode reclaim hook is intentionally driven from per-memcg contexts to free memcg-charged slab. - eventpoll: Pin files while checking reverse paths. Since struct file became SLAB_TYPESAFE_BY_RCU a concurrent close could free and recycle the file under the check which then took and dropped the f_lock of whatever live file now occupies that slot. * tag 'vfs-7.2-rc5.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (24 commits) super: fix emergency thaw deadlock on frozen block devices pidfs: make pidfs_ino_lock static eventpoll: pin files while checking reverse paths fs: push nr_cached_objects memcg gating into individual filesystems afs: Fix afs_edit_dir_remove() to get, not find, block 0 iomap: prevent ioend merge when io_private differs iomap: add comments for ifs_clear/set_range_dirty() iomap: fix out-of-bounds bitmap_set() with zero-length range iomap: fix incorrect did_zero setting in iomap_zero_iter() iomap: support invalidating partial folios iomap: correct the range of a partial dirty clear fs/super: fix emergency thaw double-unlock of s_umount pidfs: handle FS_IOC32_GETVERSION in compat ioctl ovl: check access to copy_file_range source with src mounter creds proc: Fix broken error paths for namespace links pidfs: add pidfs_dentry_open() helper selftests/pidfd: check PIDFD_THREAD survives open_by_handle_at() pidfs: preserve thread pidfds reopened by file handle ovl: fix trusted xattr escape prefix matching selftests/fuse: add ACL_DONT_CACHE regression test ...
10 daysfs: push nr_cached_objects memcg gating into individual filesystemsUsama Arif
Commit 0baad6f9b997 ("fs/super: skip non-memcg-aware nr_cached_objects in memcg slab shrink") added a check in fs/super.c that skipped every ->nr_cached_objects() hook whenever the shrinker was invoked for a non-root memcg, on the assumption that none of them honour sc->memcg. That assumption is wrong for XFS, whose inode-reclaim hook is intentionally driven from per-memcg contexts to free memcg-charged slab. Encoding a blanket "never memcg-aware" policy in fs/super.c short-circuits that path. Push the check down into the callbacks whose counters really are irrelevant to per-memcg reclaim - btrfs_nr_cached_objects() and shmem_unused_huge_count() - and drop the fs/super.c gate. Each filesystem can now lift the restriction independently if its counter later grows memcg awareness, without touching fs/super.c. Introduce mem_cgroup_shrink_is_root() in <linux/memcontrol.h> so the callbacks don't open-code "sc->memcg is NULL or root". Fixes: 0baad6f9b997 ("fs/super: skip non-memcg-aware nr_cached_objects in memcg slab shrink") Acked-by: Qi Zheng <qi.zheng@linux.dev> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Signed-off-by: Usama Arif <usama.arif@linux.dev> Link: https://patch.msgid.link/20260715103516.2410175-1-usama.arif@linux.dev Acked-by: David Sterba <dsterba@suse.com> Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com> Signed-off-by: Christian Brauner (Amutable) <brauner@kernel.org>
11 daysMerge tag 'for-7.2-rc4-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "I'm catching up with the fix backlog in the development branch, so here's a number of them and will probably send one more for this or the next rc: - relocation fixes: - skip attempting compression on reloc inodes - exclude inline extents from file extent offset checks - fix minor memory leak after error when adding reloc root - fix root cleanup after inserting and merging - fix clearing folio tags after writeback - clear logging flag of extent map before splitting - fix unsigned 32/64 type conversions when accounting dirty metadata, leading to continually exceeding threshold - fix regression in 32bit compat ioctl for subvolume info - fix type of SEARCH_TREE ioctl buffer in UAPI header - fix expression in ASSERT expression which can be unconditionally evaluated on some compilers - only account delalloc bytes for regular inodes" * tag 'for-7.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: fix GET_SUBVOL_INFO after compat refactor btrfs: free mapping node on duplicate reloc root insert btrfs: fix a regression where PAGECACHE_TAG_DIRTY is never cleared btrfs: don't propagate EXTENT_FLAG_LOGGING to split extent maps btrfs: fix u32 to s64 type conversion in dirty_metadata_bytes accounting btrfs: fix NULL pointer deref during assertion in btrfs_backref_free_node() btrfs: only account delalloc bytes for regular file inodes in btrfs_getattr() btrfs: reject inline file extents item in get_new_location() btrfs: do not try compression for data reloc inodes btrfs: declare btrfs_ioctl_search_args_v2::buf as __u8 btrfs: fix reloc root cleanup in merge_reloc_roots() btrfs: fix use-after-free on reloc root after error in insert_dirty_subvol()
12 daysbtrfs: raid56: fix scrub read assembly submitting no readsMykola Lysenko
Commit 5387bd958180 ("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: 5387bd958180 ("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>
12 daysbtrfs: zoned: skip fully truncated ordered extents at zone finishJohannes Thumshirn
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 66ff4d366e7e 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: 66ff4d366e7e ("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>
12 daysbtrfs: initialize 'args' to avoid compiler warning in btrfs_ioctl_get_csums()Paul E. McKenney
[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>
12 daysbtrfs: zoned: fix missing chunk metadata reservationGuanghui Yang
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: b6a98021e401 ("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>
12 daysbtrfs: raid56: fix an incorrect csum skip during scrubQu Wenruo
Commit 7425a2894019 ("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: 7425a2894019 ("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>
12 daysbtrfs: report missing raid stripe tree root during lookupDongjiang Zhu
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>
12 daysbtrfs: skip global block reserve accounting for rescue mountsDongjiang Zhu
[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: 8dbfc14fc736 ("btrfs: account block group tree when calculating global reserve size") Fixes: 515020900d44 ("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>
12 daysbtrfs: zoned: reset meta_write_pointer on zone resetJohannes Thumshirn
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: 453a73c3069a ("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>
12 daysbtrfs: zoned: fix deadlock between metadata writeback and transaction commitJohannes Thumshirn
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: 13bb483d32ab ("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>
12 daysbtrfs: fix leaking BTRFS_FS_STATE_REMOUNTING flagQu Wenruo
[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: eddb1a433f26 ("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>
2026-07-14Merge tag 'for-7.2-rc3-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: - fix root structure leak after relocation error - fix optimization when checksums are read from commit root, fall back to checksum root during relocation - in tree-checker, validate length of inode reference in items - validate properties before setting them - validate free space cache entries on load - transaction abort fixes - fix printing of internal trees as signed numbers - add error messages after critical lzo compression errors * tag 'for-7.2-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: print-tree: print header owner as signed btrfs: decentralize transaction aborts in create_reloc_root() btrfs: tree-checker: validate INODE_REF's namelen btrfs: lzo: add error message for invalid headers btrfs: fallback to transaction csum tree on a commit root csum miss btrfs: fix root leak if its reloc root is unexpected in merge_reloc_roots() btrfs: reject free space cache with more entries than pages btrfs: fix transaction abort logic in btrfs_fileattr_set() btrfs: validate properties before setting them
2026-07-14btrfs: fix GET_SUBVOL_INFO after compat refactorDaan De Meyer
btrfs_search_slot() returns a positive value when the search key does not exactly match an item. This is expected here, since offset 0 is used to find the first ROOT_BACKREF for the subvolume and the actual key has the parent root ID as its offset. Before the compat ioctl refactoring, the native handler still copied the filled structure to userspace when the search returned 1. After the lookup was moved to a shared helper, both native and compat callers treat the positive return value as a failure and skip copy_to_user(), leaving BTRFS_IOC_GET_SUBVOL_INFO unusable for non-top-level subvolumes. Reset ret after successfully validating and reading the ROOT_BACKREF so the helper reports success and both callers copy the result to userspace. Fixes: 538e5bdbc899 ("btrfs: add 32-bit compat ioctl for BTRFS_IOC_GET_SUBVOL_INFO") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Daan De Meyer <daan@amutable.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-14btrfs: free mapping node on duplicate reloc root insertGuanghui Yang
__add_reloc_root() allocates a mapping_node before inserting it into rc->reloc_root_tree. If rb_simple_insert() finds an existing entry, it returns the existing rb_node and leaves the newly allocated node unlinked. The error path then returns -EEXIST without freeing the new node. Since the node was never inserted into reloc_root_tree, the later cleanup in put_reloc_control() cannot find it either. Free the newly allocated node before returning -EEXIST. The callers currently assert that -EEXIST should not happen, so this is a defensive cleanup for an unexpected duplicate insert path. If the path is ever reached, the local allocation should still be released. Fixes: 57a304cfd43b ("btrfs: do not panic in __add_reloc_root") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Guanghui Yang <3497809730@qq.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-14btrfs: fix a regression where PAGECACHE_TAG_DIRTY is never clearedQu Wenruo
[BUG] The following script (already submitted as generic/798) will report incorrect dirty page numbers, with 64K page size systems and 4K fs block size: # mkfs.btrfs -s 4k -f $dev # mount $dev $mnt # xfs_io -f -c "pwrite 0 64K" -c fsync -c "cachestat 0 64K" $mnt/foobar Cached: 1, Dirty: 1, Writeback: 0, Evicted: 0, Recently Evicted: 0 Note that the dirtied page number is still 1. [CAUSE] The cachestat() goes through the XArray of the page cache, but instead of checking each folio's flag, it uses the PAGECACHE_TAG_DIRTY tag to report dirty pages. Since commit 095be159f3eb ("btrfs: unify folio dirty flag clearing"), btrfs replaced a folio_clear_dirty_for_io() call inside extent_write_cache_pages() with folio_test_dirty(). This will cause the following call sequence for the folio at file offset 0: extent_write_cache_pages() |- folio_test_dirty() | The folio is still dirty, continue to writeback. | |- extent_writepage() |- extent_writepage_io() |- submit_one_sector() for range [0, 4K) | |- btrfs_folio_clear_dirty() | |- btrfs_folio_set_writeback() | |- folio_start_writeback() | It's the first writeback block, we set the writeback | flag for the folio. | But the folio is still dirty, PAGECACHE_TAG_DIRTY is | kept | |- submit_one_sector() for range [4K, 8K) | |- btrfs_folio_clear_dirty() | |- btrfs_folio_set_writeback() | The folio already has writeback flag, no need to call | folio_start_writeback() | | ... |- submit_one_sector() for range [60K, 64K) |- btrfs_folio_clear_dirty() |- btrfs_folio_set_writeback() The folio already has writeback flag, no need to call folio_start_writeback() So the PAGECACHE_TAG_DIRTY is never cleared. Meanwhile for the old code, before that commit, the sequence looks like: extent_write_cache_pages() |- folio_clear_dirty_for_io() | The folio is still dirty, so continue to writeback. | But the folio dirty flag is cleared now. | |- extent_writepage() |- extent_writepage_io() |- submit_one_sector() for range [0, 4K) | |- btrfs_folio_clear_dirty() | |- btrfs_folio_set_writeback() | |- folio_start_writeback() | |- xas_clear(PAGECACHE_TAG) | | It's the first writeback block, we set the writeback | flag for the folio. | And the folio is not dirty, PAGECACHE_TAG_DIRTY is | cleared | |- submit_one_sector() for range [4K, 8K) | |- btrfs_folio_clear_dirty() | |- btrfs_folio_set_writeback() | The folio already has writeback flag, no need to call | folio_start_writeback() | | ... |- submit_one_sector() for range [60K, 64K) |- btrfs_folio_clear_dirty() |- btrfs_folio_set_writeback() The folio already has writeback flag, no need to call folio_start_writeback() Unlike the new code, old code will clear PAGECACHE_TAG_DIRTY for the first writeback block. There is a deeper problem, dirty and writeback folio flags are updated at very different timing. The dirty flag is only cleared when the last sub-folio block has dirty flag cleared. But the writeback flag is set when the first block starts writeback, and later blocks that go through writeback will not call folio_start_writeback() again. If we rely on folio_start_writeback() to update the PAGECACHE_TAG_DIRTY and PAGECACHE_TAG_TOWRITE, it will always be incorrect in one way or another. [FIX] Do not let folio_start_writeback() do any PAGECACHE_TAG_TOWRITE handling. Instead, manually clear both PAGECACHE_TAG_TOWRITE and PAGECACHE_TAG_DIRTY flags when the folio is no longer dirty during btrfs_subpage_set_writeback(). However this is only a hot-fix, for the long term solution we will follow iomap, by calling folio_start_writeback() immediately for the whole folio, and folio_end_writeback() after all writeback finished for the folio. Fixes: 095be159f3eb ("btrfs: unify folio dirty flag clearing") Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-14btrfs: don't propagate EXTENT_FLAG_LOGGING to split extent mapsLeo Martins
When btrfs_drop_extent_map_range() splits an extent map, the new split maps inherit the original map's flags through a local 'flags' variable. Commit f86f7a75e2fb ("btrfs: use the flags of an extent map to identify the compression type") changed the EXTENT_FLAG_LOGGING clearing to operate on em->flags instead of that local 'flags' copy, so a split of an extent map that is currently being logged wrongly inherits EXTENT_FLAG_LOGGING. The flag is then never cleared on the split, and when it is freed while still on the inode's modified_extents list (for example by the extent map shrinker) it trips the WARN_ON(!list_empty(&em->list)) in btrfs_free_extent_map() and leads to a use-after-free. Clear EXTENT_FLAG_LOGGING from the local 'flags' copy used for the splits and only clear EXTENT_FLAG_PINNED from em->flags, restoring the behaviour prior to f86f7a75e2fb. CC: Jeff Layton <jlayton@kernel.org> Link: https://lore.kernel.org/all/20260629-btrfs-skip-logging-v1-1-4e3a28c1acaf@kernel.org/ Fixes: f86f7a75e2fb ("btrfs: use the flags of an extent map to identify the compression type") Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Leo Martins <loemra.dev@gmail.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-14btrfs: fix u32 to s64 type conversion in dirty_metadata_bytes accountingDave Chen
The percpu_counter dirty_metadata_bytes is updated by negating eb->len and passing it to percpu_counter_add_batch(), whose amount parameter is s64. Since commit 84cda1a6087d ("btrfs: cache folio size and shift in extent_buffer"), eb->len is u32. The u32 result of -eb->len, when widened to the s64 parameter, becomes a large positive value instead of the intended negative value. For eb->len == 16384 the counter adds +4294950912 instead of subtracting 16384. The counter therefore grows on every metadata writeback instead of shrinking by the extent buffer size, permanently exceeding BTRFS_DIRTY_METADATA_THRESH and causing __btrfs_btree_balance_dirty() to trigger balance_dirty_pages_ratelimited() unconditionally, adding unnecessary writeback pressure. Cast eb->len to s64 before negation at both call sites so the subtraction is performed in signed 64-bit arithmetic. Reviewed-by: Filipe Manana <fdmanana@suse.com> Fixes: 84cda1a6087d ("btrfs: cache folio size and shift in extent_buffer") Signed-off-by: Dave Chen <davechen@synology.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-14btrfs: fix NULL pointer deref during assertion in btrfs_backref_free_node()Filipe Manana
In btrfs_backref_free_node() we have the following assertion: ASSERT(node->eb == NULL, "node->eb->start=%llu", node->eb->start); and a user reported the following crash: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 0 UID: 0 PID: 10422 Comm: syz.0.17 Not tainted 7.1.0-02765-g6b5a2b7d9bc1-dirty #44 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:btrfs_backref_free_node fs/btrfs/backref.c:3057 [inline] RIP: 0010:btrfs_backref_free_node+0xb9/0x200 fs/btrfs/backref.c:3051 Code: 00 fc ff (...) RSP: 0018:ffa0000006b0f3c0 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff840eb78b RDX: 0000000000000000 RSI: ffffffff840eafa5 RDI: ff110000742ab768 RBP: ff110000742ab700 R08: 0000000000000000 R09: 0000000000000000 R10: ff110000742ab700 R11: 00000000000a81f9 R12: ff11000107a92020 R13: ff1100005c182ea8 R14: 0000000000000000 R15: dffffc0000000000 FS: 0000555575536500(0000) GS:ff11000183985000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa3d0e9d580 CR3: 000000002232a000 CR4: 0000000000753ef0 PKRU: 00000000 Call Trace: <TASK> btrfs_backref_cleanup_node+0x27/0x30 fs/btrfs/backref.c:3133 relocate_tree_block fs/btrfs/relocation.c:2604 [inline] relocate_tree_blocks+0x11b0/0x1a20 fs/btrfs/relocation.c:2707 relocate_block_group+0x499/0xf30 fs/btrfs/relocation.c:3635 do_nonremap_reloc fs/btrfs/relocation.c:5323 [inline] btrfs_relocate_block_group+0x1749/0x5fb0 fs/btrfs/relocation.c:5490 btrfs_relocate_chunk+0x12b/0x950 fs/btrfs/volumes.c:3647 __btrfs_balance fs/btrfs/volumes.c:4586 [inline] btrfs_balance+0x1c7f/0x55c0 fs/btrfs/volumes.c:4973 btrfs_ioctl_balance fs/btrfs/ioctl.c:3474 [inline] btrfs_ioctl+0x38a4/0x5d20 fs/btrfs/ioctl.c:5570 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:583 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x11f/0x860 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fb38e3b56dd Code: 02 b8 ff (...) RSP: 002b:00007fff04115788 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fb38f6b0020 RCX: 00007fb38e3b56dd RDX: 00002000000003c0 RSI: 00000000c4009420 RDI: 0000000000000004 RBP: 00007fb38e451b48 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fb38f6b0020 R15: 00007fb38f6b002c </TASK> It seems that this happens on some systems for some reason, when the ASSERT() macro calls the inline function verify_assert_printk_format() to evaluate the format string and arguments, causing the NULL pointer dereference on node->eb. So change the assertion to check for a NULL node->eb before dereferencing it. Also, while at it, make the assertion more useful by printing the owner of the extent buffer as well as its level. Reported-by: Yue Sun <samsun1006219@gmail.com> Link: https://lore.kernel.org/linux-btrfs/20260626065542.38413-1-samsun1006219@gmail.com/ Fixes: c4e7778580d6 ("btrfs: use verbose assertions in backref.c") Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-14btrfs: only account delalloc bytes for regular file inodes in btrfs_getattr()Dave Chen
btrfs_getattr() unconditionally reads BTRFS_I(inode)->new_delalloc_bytes and adds it (sector-aligned) to stat->blocks for every inode type. However, new_delalloc_bytes lives in a union with last_dir_index_offset: union { u64 new_delalloc_bytes; /* files only */ u64 last_dir_index_offset; /* directories only */ }; For a directory inode this memory holds last_dir_index_offset, which is set during directory logging (e.g. flush_dir_items_batch()) to the offset of the last logged BTRFS_DIR_INDEX_KEY. That offset grows with the number of entries ever created in the directory (dir indexes are monotonic and never reused), so it can be arbitrarily large. As a result, after a directory has been logged (e.g. via an fsync that triggers directory logging), btrfs_getattr() reports inflated st_blocks for that directory. The inflation is purely in-core and disappears after the inode is evicted and reloaded (btrfs_alloc_inode() zeroes the union), e.g. after a remount. Reproducer (on a btrfs filesystem): D=/mnt/btrfs/d mkdir -p $D for i in $(seq 1 20000); do touch $D/f$i; done sync # commit, push dir index high touch $D/trigger # dirty the dir in a new transaction xfs_io -c fsync $D # log the directory -> sets last_dir_index_offset stat -c '%b' $D # st_blocks is now inflated (e.g. 40) # umount + mount -> st_blocks drops back to the correct value The evict path already knows this union is type-dependent and guards the corresponding WARN_ON with !S_ISDIR() in btrfs_destroy_inode(); only btrfs_getattr() was missing the equivalent check. Only read new_delalloc_bytes for regular files, which are the only inodes that ever set it. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Dave Chen <davechen@synology.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-14btrfs: reject inline file extents item in get_new_location()Qu Wenruo
Commit a6908f88c9da ("btrfs: validate data reloc tree file extent item members") introduced extra checks on file extent items for data reloc inodes, but it checked the file extent offset without checking if the file extent is inlined. This can lead to either false alerts (as the offset member is inside the inlined data) or even reading beyond the item range. This has already triggered a warning in a syzbot report. Although the root fix is to avoid compression for data reloc inodes, for the sake of consistency, reject inlined file extents first. Fixes: a6908f88c9da ("btrfs: validate data reloc tree file extent item members") CC: stable@vger.kernel.org Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-14btrfs: do not try compression for data reloc inodesQu Wenruo
[BUG] There is a syzbot report that the check inside get_new_location() triggered: BTRFS info (device loop0): found 31 extents, stage: move data extents BTRFS info (device loop0): leaf 8908800 gen 16 total ptrs 28 free space 1676 owner 18446744073709551607 item 0 key (256 INODE_ITEM 0) itemoff 3835 itemsize 160 inode generation 5 transid 0 size 0 nbytes 0 block group 0 mode 40755 links 1 uid 0 gid 0 rdev 0 sequence 0 flags 0x0 atime 1669132761.0 ctime 1669132761.0 mtime 1669132761.0 otime 0.0 item 1 key (256 INODE_REF 256) itemoff 3823 itemsize 12 index 0 name_len 2 item 2 key (258 INODE_ITEM 0) itemoff 3663 itemsize 160 inode generation 1 transid 16 size 733184 nbytes 106496 block group 0 mode 100600 links 0 uid 0 gid 0 rdev 0 sequence 24 flags 0x18 item 3 key (258 EXTENT_DATA 0) itemoff 3595 itemsize 68 generation 16 type 0 inline extent data size 47 ram_bytes 4096 compression 1 [...] item 27 key (18446744073709551611 ORPHAN_ITEM 258) itemoff 2376 itemsize 0 BTRFS error (device loop0): unexpected non-zero offset in file extent item for data reloc inode 258 key offset 0 offset 9277520992061368337 ------------[ cut here ]------------ btrfs_abort_should_print_stack(__error) [CAUSE] The above dump tree shows the first file extent item is inlined, which should make no sense for data reloc inodes, as such inodes just represent where the data extents are in the relocation destination chunk. However the relocation path preallocates space for each block, then dirties them, cluster by cluster. It's possible to have a single block at the beginning of the block group, and no other block in the same cluster. So relocation will preallocate a file extent for that block and dirty the first block. Then memory pressure forces the data reloc inode to be written back, before any other blocks are dirtied/allocated. Finally commit 3eaf5f082c4c ("btrfs: extract inlined creation into a dedicated delalloc helper") changed the sequence of delalloc. Before that commit we always tried NOCOW first, so that dirtied block would be written back into the preallocated space, and appear as a regular extent. But with that commit, we always try inline first, and since compression is forced, we try compressing the first block, and then inline the compressed data, resulting in the above inlined file extent in the data reloc tree. Then the check in get_new_location() will check the file offset, without checking if the file extent is inlined or not, resulting in the above failure. [FIX] Do not allow compression for data reloc inodes. Since data reloc inode sizes are always block aligned, as long as we do not compress, @data_len will always be at least one block, and that will cause can_cow_file_range_inline() to return false, thus no inlined extent will be created. Reported-by: syzbot+d950c6ba09b79f6e1864@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/6a373dc5.764cf64f.168fbe.0001.GAE@google.com/ Fixes: 3eaf5f082c4c ("btrfs: extract inlined creation into a dedicated delalloc helper") CC: stable@vger.kernel.org Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-14btrfs: fix reloc root cleanup in merge_reloc_roots()Filipe Manana
If the root we got has zero root refs in its root item, we are resetting the root's ->reloc_root without using barriers like we do everywhere else. Sashiko complained about this while reviewing another patch, and it's correct (see the Link tag below). Also, we should not clear BTRFS_ROOT_DEAD_RELOC_TREE from the root unless the root points to the reloc root we have. Fix this by using clear_reloc_root(), which issues the memory barrier after setting the root's ->reloc_root to NULL and before clearing the bit BTRFS_ROOT_DEAD_RELOC_TREE from the root. Link: https://sashiko.dev/#/patchset/cf84f1a217c719e25b6b69e4298dd7afd36c9427.1781194426.git.fdmanana%40suse.com Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-07-14btrfs: fix use-after-free on reloc root after error in insert_dirty_subvol()Filipe Manana
If during relocation we fail in insert_dirty_subvol() because btrfs_update_reloc_root() returned an error, we will leave a root's reloc_root field pointing to a reloc root that was freed instead of NULL, resulting later in a use-after-free, or double free attempt during unmount. The sequence of steps is this: 1) During relocation the call to btrfs_update_reloc_root() in insert_dirty_subvol() fails, so insert_dirty_subvol() returns the error to merge_reloc_root() without adding the root to the list rc->dirty_subvol_roots; 2) Then merge_reloc_root() aborts the current transaction because insert_dirty_subvol() returned an error; 3) Up the call chain, merge_reloc_roots() gets the error, adds the reloc root for root X to the local reloc_roots list and jumps to the 'out' label, where it calls free_reloc_roots() to free all the reloc roots in the local reloc_roots list. This frees the reloc root for root X; 4) We go up the call chain to relocate_block_group() which calls clean_dirty_subvols() to go over dirty roots and set their ->reloc_root field to NULL, but root X is not in the dirty_subvol_roots list, so its ->reloc_root still points to a reloc root; 5) Relocation finishes, with an error and a transaction abort, but the ->reloc_root field for root X still points to the reloc root that was freed in step 3; 6) When unmounting the fs we end up calling: btrfs_free_fs_roots() btrfs_drop_and_free_fs_root() --> calls btrfs_put_root() against root X's ->reloc_root which is not NULL and points to the already freed reloc root in step 4 above Resulting in a use-after-free to a double free attempt. Syzbot reported this with the following dmesg/syslog: [ 106.004389][ T5339] BTRFS error (device loop0 state A): Transaction aborted (error -5) [ 106.014266][ T5339] BTRFS: error (device loop0 state A) in merge_reloc_root:1655: errno=-5 IO failure [ 106.021891][ T1061] BTRFS error (device loop0 state A): error while writing out transaction: -5 [ 106.026964][ T1061] BTRFS warning (device loop0 state A): Skipping commit of aborted transaction. [ 106.033807][ T5340] BTRFS error (device loop0 state A): bdev /dev/loop0 errs: wr 3, rd 0, flush 0, corrupt 0, gen 0 [ 106.039265][ T1061] BTRFS: error (device loop0 state A) in cleanup_transaction:2067: errno=-5 IO failure [ 106.044382][ T5339] BTRFS info (device loop0 state EA): forced readonly [ 106.074329][ T5339] BTRFS: error (device loop0 state EA) in merge_reloc_roots:1887: errno=-5 IO failure [ 106.081004][ T5356] BTRFS info (device loop0 state EA): scrub: started on devid 1 [ 106.085611][ T5339] BTRFS info (device loop0 state EA): balance: ended with status: -30 [ 106.089517][ T5356] BTRFS info (device loop0 state EA): scrub: not finished on devid 1 with status: -30 [ 106.662365][ T5338] BTRFS info (device loop0 state EA): last unmount of filesystem 3a375e4e-b156-4d76-a2ad-16e198ce1409 [ 106.682946][ T5338] ================================================================== [ 106.686574][ T5338] BUG: KASAN: slab-use-after-free in btrfs_put_root+0x2f/0x250 [ 106.690090][ T5338] Write of size 4 at addr ffff88803f978630 by task syz.0.0/5338 [ 106.693173][ T5338] [ 106.694279][ T5338] CPU: 0 UID: 0 PID: 5338 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) [ 106.694293][ T5338] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 106.694300][ T5338] Call Trace: [ 106.694308][ T5338] <TASK> [ 106.694314][ T5338] dump_stack_lvl+0xe8/0x150 [ 106.694331][ T5338] print_address_description+0x55/0x1e0 [ 106.694343][ T5338] ? btrfs_put_root+0x2f/0x250 [ 106.694358][ T5338] print_report+0x58/0x70 [ 106.694368][ T5338] kasan_report+0x117/0x150 [ 106.694384][ T5338] ? btrfs_put_root+0x2f/0x250 [ 106.694399][ T5338] kasan_check_range+0x264/0x2c0 [ 106.694416][ T5338] btrfs_put_root+0x2f/0x250 [ 106.694430][ T5338] btrfs_drop_and_free_fs_root+0x160/0x210 [ 106.694447][ T5338] btrfs_free_fs_roots+0x2f9/0x3c0 [ 106.694464][ T5338] ? __pfx_btrfs_free_fs_roots+0x10/0x10 [ 106.694479][ T5338] ? free_root_pointers+0x5bf/0x5f0 [ 106.694494][ T5338] close_ctree+0x798/0x12d0 [ 106.694511][ T5338] ? __pfx_close_ctree+0x10/0x10 [ 106.694526][ T5338] ? _raw_spin_unlock_irqrestore+0x74/0x80 [ 106.694599][ T5338] ? rcu_preempt_deferred_qs_irqrestore+0x906/0xbc0 [ 106.694620][ T5338] ? __rcu_read_unlock+0x83/0xe0 [ 106.694636][ T5338] ? btrfs_put_super+0x48/0x1c0 [ 106.694652][ T5338] ? __pfx_btrfs_put_super+0x10/0x10 [ 106.694667][ T5338] generic_shutdown_super+0x13d/0x2d0 [ 106.694682][ T5338] kill_anon_super+0x3b/0x70 [ 106.694695][ T5338] btrfs_kill_super+0x41/0x50 [ 106.694710][ T5338] deactivate_locked_super+0xbc/0x130 [ 106.694722][ T5338] cleanup_mnt+0x437/0x4d0 [ 106.694736][ T5338] ? _raw_spin_unlock_irq+0x23/0x50 [ 106.694752][ T5338] task_work_run+0x1d9/0x270 [ 106.694769][ T5338] ? __pfx_task_work_run+0x10/0x10 [ 106.694784][ T5338] ? do_raw_spin_unlock+0x4d/0x210 [ 106.694802][ T5338] do_exit+0x70f/0x22c0 [ 106.694817][ T5338] ? trace_irq_disable+0x3b/0x140 [ 106.694835][ T5338] ? __pfx_do_exit+0x10/0x10 [ 106.694848][ T5338] ? preempt_schedule_thunk+0x16/0x30 [ 106.694863][ T5338] ? preempt_schedule_common+0x82/0xd0 [ 106.694878][ T5338] ? preempt_schedule_thunk+0x16/0x30 [ 106.694892][ T5338] do_group_exit+0x21b/0x2d0 [ 106.694906][ T5338] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 106.694918][ T5338] __x64_sys_exit_group+0x3f/0x40 [ 106.694932][ T5338] x64_sys_call+0x221a/0x2240 [ 106.694944][ T5338] do_syscall_64+0x174/0x580 [ 106.694954][ T5338] ? clear_bhb_loop+0x40/0x90 [ 106.694967][ T5338] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 106.694978][ T5338] RIP: 0033:0x7f958ef9ce59 [ 106.694988][ T5338] Code: Unable to access opcode bytes at 0x7f958ef9ce2f. [ 106.694994][ T5338] RSP: 002b:00007fffd4058318 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 106.695008][ T5338] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f958ef9ce59 [ 106.695015][ T5338] RDX: 00007f958c3f8000 RSI: 0000000000000000 RDI: 0000000000000000 [ 106.695022][ T5338] RBP: 0000000000000003 R08: 0000000000000000 R09: 00007f958f1e73e0 [ 106.695028][ T5338] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 106.695034][ T5338] R13: 00007f958f1e73e0 R14: 0000000000000003 R15: 00007fffd40583d0 [ 106.695046][ T5338] </TASK> [ 106.695050][ T5338] [ 106.821635][ T5338] Allocated by task 1061: [ 106.823446][ T5338] kasan_save_track+0x3e/0x80 [ 106.825498][ T5338] __kasan_kmalloc+0x93/0xb0 [ 106.827381][ T5338] __kmalloc_cache_noprof+0x31c/0x660 [ 106.829525][ T5338] btrfs_alloc_root+0x75/0x930 [ 106.831458][ T5338] read_tree_root_path+0x127/0xb00 [ 106.833556][ T5338] btrfs_read_tree_root+0x34/0x60 [ 106.835553][ T5338] create_reloc_root+0x6b3/0xcb0 [ 106.837556][ T5338] btrfs_init_reloc_root+0x2ec/0x4b0 [ 106.839557][ T5338] record_root_in_trans+0x2ab/0x350 [ 106.841685][ T5338] btrfs_record_root_in_trans+0x15c/0x180 [ 106.844237][ T5338] start_transaction+0x39c/0x1820 [ 106.846638][ T5338] btrfs_finish_one_ordered+0x88e/0x2680 [ 106.849436][ T5338] btrfs_work_helper+0x37b/0xc20 [ 106.851549][ T5338] process_scheduled_works+0xb5d/0x1860 [ 106.853807][ T5338] worker_thread+0xa53/0xfc0 [ 106.855773][ T5338] kthread+0x389/0x470 [ 106.857548][ T5338] ret_from_fork+0x514/0xb70 [ 106.859493][ T5338] ret_from_fork_asm+0x1a/0x30 [ 106.861504][ T5338] [ 106.862527][ T5338] Freed by task 5339: [ 106.864224][ T5338] kasan_save_track+0x3e/0x80 [ 106.866180][ T5338] kasan_save_free_info+0x46/0x50 [ 106.868371][ T5338] __kasan_slab_free+0x5c/0x80 [ 106.870462][ T5338] kfree+0x1c5/0x640 [ 106.872180][ T5338] __del_reloc_root+0x341/0x3b0 [ 106.874290][ T5338] free_reloc_roots+0x5f/0x90 [ 106.876282][ T5338] merge_reloc_roots+0x73f/0x8a0 [ 106.878489][ T5338] relocate_block_group+0xbcc/0xe70 [ 106.880742][ T5338] do_nonremap_reloc+0xa8/0x5b0 [ 106.882885][ T5338] btrfs_relocate_block_group+0x7e6/0xc40 [ 106.885336][ T5338] btrfs_relocate_chunk+0x115/0x820 [ 106.887502][ T5338] __btrfs_balance+0x1db0/0x2ae0 [ 106.889543][ T5338] btrfs_balance+0xaf3/0x11b0 [ 106.891456][ T5338] btrfs_ioctl_balance+0x3d3/0x610 [ 106.893672][ T5338] __se_sys_ioctl+0xfc/0x170 [ 106.895530][ T5338] do_syscall_64+0x174/0x580 [ 106.897518][ T5338] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 106.900101][ T5338] [ 106.901123][ T5338] The buggy address belongs to the object at ffff88803f978000 [ 106.901123][ T5338] which belongs to the cache kmalloc-4k of size 4096 [ 106.906907][ T5338] The buggy address is located 1584 bytes inside of [ 106.906907][ T5338] freed 4096-byte region [ffff88803f978000, ffff88803f979000) [ 106.912980][ T5338] [ 106.914022][ T5338] The buggy address belongs to the physical page: [ 106.916716][ T5338] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3f978 [ 106.920390][ T5338] head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 [ 106.923834][ T5338] flags: 0x4fff00000000040(head|node=1|zone=1|lastcpupid=0x7ff) [ 106.927104][ T5338] page_type: f5(slab) [ 106.928898][ T5338] raw: 04fff00000000040 ffff88801ac42140 dead000000000122 0000000000000000 [ 106.932507][ T5338] raw: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000 [ 106.936193][ T5338] head: 04fff00000000040 ffff88801ac42140 dead000000000122 0000000000000000 [ 106.939856][ T5338] head: 0000000000000000 0000000800040004 00000000f5000000 0000000000000000 [ 106.943601][ T5338] head: 04fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff [ 106.947268][ T5338] head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 [ 106.950988][ T5338] page dumped because: kasan: bad access detected [ 106.953710][ T5338] page_owner tracks the page as allocated [ 106.956198][ T5338] page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 24, tgid 24 (kworker/u4:2), ts 105728970387, free_ts 29540875453 [ 106.964984][ T5338] post_alloc_hook+0x22d/0x280 [ 106.966956][ T5338] get_page_from_freelist+0x2593/0x2610 [ 106.969307][ T5338] __alloc_frozen_pages_noprof+0x18d/0x380 [ 106.971839][ T5338] allocate_slab+0x77/0x660 [ 106.973709][ T5338] refill_objects+0x339/0x3d0 [ 106.975696][ T5338] __pcs_replace_empty_main+0x321/0x720 [ 106.978136][ T5338] __kmalloc_node_track_caller_noprof+0x572/0x7b0 [ 106.981009][ T5338] __alloc_skb+0x2c1/0x7d0 [ 106.982983][ T5338] nsim_dev_trap_report_work+0x29a/0xb90 [ 106.985356][ T5338] process_scheduled_works+0xb5d/0x1860 [ 106.987710][ T5338] worker_thread+0xa53/0xfc0 [ 106.989847][ T5338] kthread+0x389/0x470 [ 106.991727][ T5338] ret_from_fork+0x514/0xb70 [ 106.993722][ T5338] ret_from_fork_asm+0x1a/0x30 [ 106.995900][ T5338] page last free pid 77 tgid 77 stack trace: [ 106.998479][ T5338] __free_frozen_pages+0xc1c/0xd30 [ 107.000819][ T5338] vfree+0x1d1/0x2f0 [ 107.002631][ T5338] delayed_vfree_work+0x55/0x80 [ 107.004848][ T5338] process_scheduled_works+0xb5d/0x1860 [ 107.007366][ T5338] worker_thread+0xa53/0xfc0 [ 107.009388][ T5338] kthread+0x389/0x470 [ 107.011177][ T5338] ret_from_fork+0x514/0xb70 [ 107.013313][ T5338] ret_from_fork_asm+0x1a/0x30 [ 107.015454][ T5338] [ 107.016460][ T5338] Memory state around the buggy address: [ 107.019052][ T5338] ffff88803f978500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 107.022691][ T5338] ffff88803f978580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 107.026264][ T5338] >ffff88803f978600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 107.029721][ T5338] ^ [ 107.032062][ T5338] ffff88803f978680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 107.035547][ T5338] ffff88803f978700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 107.038865][ T5338] ================================================================== Fix this by resetting a root's ->reloc_root if we get an error while trying to merge a reloc root. Reported-by: syzbot+b3d472d13f9d7bf20669@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/6a1ebde9.c1435f33.112120.0176.GAE@google.com/ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-30btrfs: print-tree: print header owner as signedQu Wenruo
When dumping a tree block, btrfs_header::owner is printed as unsigned, which can result in numbers that are hard to read, e.g.: BTRFS info (device loop0): leaf 8908800 gen 16 total ptrs 28 free space 1676 owner 18446744073709551607 For the above output, 18446744073709551607 is (s64)-9, the root id of data reloc tree. Despite those predefined root ids that are already negative, existing subvolume trees will not have any negative values, as subvolume trees can only utilize the lower 48 bits, so there will be no output change for existing subvolumes, thus no extra confusion. Reviewed-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Sun YangKai <sunk67188@gmail.com> Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-30btrfs: decentralize transaction aborts in create_reloc_root()Johannes Thumshirn
Decentralize transaction aborts in create_reloc_root(), so that it is obvious which call failed and what caused the transaction abort. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-30btrfs: tree-checker: validate INODE_REF's namelenWeiming Shi
[BUG] A crafted btrfs image can trigger the following crash: BUG: unable to handle page fault for address: ffffd1dc42884000 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page CPU: 9 UID: 0 PID: 1034 Comm: poc Not tainted 7.1.0-rc4-custom+ #383 PREEMPT(full) 46af0a92938a63be7132e0dfd71e62327c51d5c2 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022 RIP: 0010:memcpy+0xc/0x10 Call Trace: <TASK> read_extent_buffer+0xe4/0x100 [btrfs 3cf0785dd58fec8c5ff84633b772f17ce1f92a8f] btrfs_get_name+0x15e/0x1e0 [btrfs 3cf0785dd58fec8c5ff84633b772f17ce1f92a8f] reconnect_path+0x165/0x390 exportfs_decode_fh_raw+0x337/0x400 ? drop_caches_sysctl_handler+0xb0/0xb0 </TASK> ---[ end trace 0000000000000000 ]--- RIP: 0010:memcpy+0xc/0x10 Kernel panic - not syncing: Fatal exception [CAUSE] TThe crafted image has the following corrupted INODE_REF item: item 9 key (258 INODE_REF 257) itemoff 11544 itemsize 4106 index 2 namelen 4096 name: d\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000 The itemsize matches the namelen, but the namelen is 4096, way larger than normal name length limit (BTRFS_NAME_LEN, 255). Meanwhile the memory of the @name is only 255 byte sized, this will cause out-of-boundary access, and cause the above crash. [FIX] Add extra namelen verification for INODE_REF, just like what we have done in ROOT_REF checks. Now the crafted image can be rejected gracefully: BTRFS critical (device dm-2): corrupt leaf: root=5 block=30572544 slot=14 ino=259, invalid inode ref name length, has 4096 expect [1, 255] BTRFS error (device dm-2): read time tree block corruption detected on logical 30572544 mirror 2 Reported-by: Xiang Mei <xmei5@asu.edu> Link: https://lore.kernel.org/linux-btrfs/aik0hEV6ehKx6Ldv@Air.local/ Acked-by: Weiming Shi <bestswngs@gmail.com> Signed-off-by: Weiming Shi <bestswngs@gmail.com> [ Rebase, add a Link: tag, add an simple cause analyze ] Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-30btrfs: lzo: add error message for invalid headersQu Wenruo
Inside btrfs we always pair -EUCLEAN error with an error message to indicate which data is corrupted. However there are 3 cases inside lzo decompression where there is no error message for corrupted headers. Add those missing error messages to show exactly where the corruption is. Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-30btrfs: fallback to transaction csum tree on a commit root csum missBoris Burkov
We have been running with commit root csums enabled for some time and have noticed a slight uptick in zero csum errors. Investigating those revealed that they were same transaction reads of extents that were just relocated, but the extent map generation was long ago. It turns out that relocation intentionally does not update the extent generation (replace_file_extents()), but must write a new csum since the data has moved, so we must account for this with commit root csum reading. Luckily this is a short lived condition: after the relocation transaction the commit root will once again have the csum. So we can add a generic fallback to the lookup to try again with the transaction csum root. Fixes: f07b855c56b1 ("btrfs: try to search for data csums in commit root") Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Boris Burkov <boris@bur.io> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-30btrfs: fix root leak if its reloc root is unexpected in merge_reloc_roots()Filipe Manana
If we have an unexpected reloc_root for our root, we jump to the out label but never drop the reference we obtained for root, resulting in a leak. Add a missing btrfs_put_root() call. Fixes: 24213fa46c70 ("btrfs: do proper error handling in merge_reloc_roots") Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-30btrfs: reject free space cache with more entries than pagesXiang Mei
When loading a v1 free space cache, __load_free_space_cache() takes num_entries and num_bitmaps straight from the on-disk btrfs_free_space_header. That header is stored in the tree_root under a key with type 0, which the tree-checker has no case for, so neither count is validated before the load trusts it. The load loops num_entries times and maps the next page whenever the current one runs out, going through io_ctl_check_crc() -> io_ctl_map_page(), which does io_ctl->pages[io_ctl->index++]. But pages[] is allocated in io_ctl_init() from the cache inode's i_size, not from num_entries: num_pages = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE); io_ctl->pages = kcalloc(num_pages, sizeof(struct page *), GFP_NOFS); So if num_entries claims more records than the pages can hold, io_ctl->index runs off the end of pages[]. The write side never hits this because io_ctl_add_entry() and io_ctl_add_bitmap() both stop once io_ctl->index >= io_ctl->num_pages; the read side just never had the same check. To trigger it, take a clean cache (num_entries = <N> here), set num_entries in the header to 0x10000, and fix up the leaf checksum so it still passes the tree-checker. The cache inode has i_size = 65536, so num_pages is 16 and pages[] is a 16-pointer (kmalloc-128) array. The load now tries to read 65536 entries, io_ctl->index walks up to 16, and pages[16] is read past the array: BUG: KASAN: slab-out-of-bounds in io_ctl_check_crc (fs/btrfs/free-space-cache.c:420 fs/btrfs/free-space-cache.c:565) Read of size 8 at addr ffff88800c833a80 by task kworker/u8:3/58 io_ctl_check_crc (fs/btrfs/free-space-cache.c:420 fs/btrfs/free-space-cache.c:565) __load_free_space_cache (fs/btrfs/free-space-cache.c:655 fs/btrfs/free-space-cache.c:820) load_free_space_cache (fs/btrfs/free-space-cache.c:1017) caching_thread (fs/btrfs/block-group.c:880) btrfs_work_helper (fs/btrfs/async-thread.c:312) process_one_work worker_thread kthread ret_from_fork free-space-cache.c:420 is io_ctl_map_page(), inlined into io_ctl_check_crc() at line 565, which is why that is the frame KASAN names. The out-of-bounds slot is then treated as a struct page and handed to crc32c(), so the bad read turns into a GP fault. Add the missing check to io_ctl_check_crc(), which is where both the entry loop and the bitmap loop end up. When num_entries is too large the load now fails like any corrupt cache: __load_free_space_cache() drops it and rebuilds the free space from the extent tree, so a valid cache is never rejected. Reported-by: Weiming Shi <bestswngs@gmail.com> Fixes: 5b0e95bf607d ("Btrfs: inline checksums into the disk free space cache") Link: https://lore.kernel.org/linux-btrfs/CAPpSM+RMPByMCKXvM5QFKToxsyNccfuFLWMdD0mfd0wh2Ja62w@mail.gmail.com/ Assisted-by: Claude:claude-opus-4-8 Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Xiang Mei <xmei5@asu.edu> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-30btrfs: fix transaction abort logic in btrfs_fileattr_set()Filipe Manana
There's no need to abort the transaction if we failed to set or delete a property, as we haven't done any change. However we need to abort if we set a property or delete a property and then fail to update the inode item, as that would leave the inode's state in subvolume tree inconsistent. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-30btrfs: validate properties before setting themFilipe Manana
We set the xattr and then attempt to apply the property. If the apply fails we then attempt to delete the xattr to avoid an inconsistency. However we don't verify if the deletion succeed, so if it fails we leave an inconsistency between the state in the btree and the in-memory inode. Address this by validating first if we can apply the property, then set the xattr, then apply the property, and this last step should not fail since the validation succeeded before - assert that it does not fail but leave code to attempt to delete the xattr if it happens, and then abort the transaction only if the xattr delete failed. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-21Merge tag 'mm-nonmm-stable-2026-06-21-10-22' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: - "taskstats: fix TGID dead-thread stat retention" (Yiyang Chen) Fix a taskstats TGID aggregation bug where fields added in the TGID query path were not preserved after thread exit, and adds a kselftest covering the regression. - "lib/tests: string_helpers: Slight improvements" (Andy Shevchenko) Improve lib/tests/string_helpers_kunit.c a little - "lib/base64: decode fixes" (Josh Law) Address minor issues in lib/base64.c - "selftests/filelock: Make output more kselftestish" (Mark Brown) Make the output from the ofdlocks test a bit easier for tooling to work with. Also ignore the generated file - "uaccess: unify inline vs outline copy_{from,to}_user() selection" (Yury Norov) Simplify the usercopy code by removing the selectability of inlining copy_{from,to}_user(). - "ocfs2: validate inline xattr header consumers" (ZhengYuan Huang) Fix a number of possible issues in the ocfs2 xattr code - "lib and lib/cmdline enhancements" (Dmitry Antipov) Provide additional robustness checking in the cmdline handling code and its in-kernel testing and selftests - "cleanup the RAID6 P/Q library" (Christoph Hellwig) Clean up the RAID6 P/Q library to match the recent updates to the RAID 5 XOR library and other CRC/crypto libraries - "ocfs2: harden inode validators against forged metadata" (Michael Bommarito) Add three structural checks to OCFS2 dinode validation so malformed on-disk fields are rejected before ocfs2_populate_inode() copies them into the in-core inode - "lib/raid: replace __get_free_pages() call with kmalloc()" (Mike Rapoport) Clean up the lib/raid code by using kmalloc() in more places * tag 'mm-nonmm-stable-2026-06-21-10-22' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (108 commits) ocfs2: fix circular locking dependency in ocfs2_dio_end_io_write ocfs2: fix NULL h_transaction deref in ocfs2_assure_trans_credits lib: interval_tree_test: validate benchmark parameters ocfs2: avoid moving extents to occupied clusters treewide: fix transposed "sign" typos and update spelling.txt ocfs2: fix UBSAN array-index-out-of-bounds in ocfs2_sum_rightmost_rec fat: reject BPB volumes whose data area starts beyond total sectors selftests/uevent: increase __UEVENT_BUFFER_SIZE to avoid ENOBUFS on busy systems lib/test_firmware: allocate the configured into_buf size fs: efs: remove unneeded debug prints checkpatch: cuppress warnings when Reported-by: is followed by Link: MAINTAINERS: add Alexander as a kcov reviewer mailmap: update Alexander Sverdlin's Email addresses fs: fat: inode: replace sprintf() with scnprintf() ocfs2: fix out-of-bounds write in ocfs2_remove_refcount_extent ocfs2: fix race between ocfs2_control_install_private() and ocfs2_control_release() ocfs2/dlm: require a ref for locking_state debugfs open ocfs2: reject FITRIM ranges shorter than a cluster ocfs2: validate fast symlink target during inode read ocfs2: add journal NULL check in ocfs2_checkpoint_inode() ...
2026-06-17Merge tag 'wq-for-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds
Pull workqueue updates from Tejun Heo: - Continued progress toward making alloc_workqueue() unbound by default: more callers converted to WQ_PERCPU / system_percpu_wq / system_dfl_wq, and new warnings for queues that use neither WQ_PERCPU nor WQ_UNBOUND or the legacy system_wq / system_unbound_wq. - Misc: drop the now-trivial apply_wqattrs_lock()/unlock() wrappers, forbid the TEST_WORKQUEUE benchmark from being built-in, and fix a spurious pointer level in the worker debug-dump path. * tag 'wq-for-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: drm/bridge: anx7625: Add WQ_PERCPU add to alloc_workqueue wifi: ath6kl: fix invalid workqueue flags in ath6kl_usb_create() btrfs: Drop WQ_PERCPU from ordered_flags in btrfs_init_workqueues() workqueue: Add warnings and ensure one among WQ_PERCPU or WQ_UNBOUND is present workqueue: Add warnings and fallback if system_{unbound}_wq is used workqueue: drop spurious '*' from print_worker_info() fn declaration workqueue: forbid TEST_WORKQUEUE from being built-in workqueue: drop apply_wqattrs_lock()/unlock() wrappers umh: replace use of system_unbound_wq with system_dfl_wq rapidio: rio: add WQ_PERCPU to alloc_workqueue users media: ddbridge: add WQ_PERCPU to alloc_workqueue users platform: cznic: turris-omnia-mcu: replace use of system_wq with system_percpu_wq media: synopsys: hdmirx: replace use of system_unbound_wq with system_dfl_wq virt: acrn: Add WQ_PERCPU to alloc_workqueue users
2026-06-16Merge tag 'for-7.2-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs updates from David Sterba: "The most noticeable change is to enable large folios by default, it's been in testing for a few releases. Related to that is huge folio support (still under experimental config). Otherwise a few ioctl updates, performance improvements and usual fixes and core changes. User visible changes: - enable large folios by default, added in 6.17 (under experimental build), no feature limitations, a big change internally - new ioctl to return raw checksums to userspace (a bit tricky given compression and tail extents), can be used for mkfs and deduplication optimizations - provide stable UUID for e.g. overlayfs and temp_fsid, also reflected in statvfs() field f_fsid, internal dev_t is hashed in to allow cloning - add 32bit compat version of GET_SUBVOL_INFO ioctl - in experimental build, support huge folios (up to 2M) Performance related improvements/changes: - limit bio size to the estimated optimum derived from the queue, this prevents build up of too much data for writeback, which could cause latency spikes (reported improvement 15% on sequential writes) - don't force direct IO to be serialized, forgotten change during mount API port, brings back +60% of throughput - lockless calculation of number of shrinkable extent maps, improve performance with many memcg allocated objects Notable fixes: - in zoned mode, fix a deadlock due to zone reclaim and relocation when space needs to be flushed - don't trim device which is internally not tracked as writeable (e.g. when missing device is being rescanned) - fix deadlock when cloning inline extent and mounted with flushoncommit - fix false IO failures after direct IO falls back to buffered write in some cases Core: - remove COW fixup mechanism completely; detect and fix changes to pages outside of filesystem tracking, guaranteed since 5.8, grace period is over - remove 2K block size support, experimental to test subpage code on x86_64 but now it would block folio changes - tree-checker improvements of: - free-space cache and tree items - root reference and backref items - extent state exceptions in reloc tree - subpage mode updates: - code optimizations, simplify tracking bitmaps - re-enable readahead of compressed extent - extend bitmap size to cover huge folios - add tracepoints related to sync, tree-log and transactions - device stats item tracking unification, remove item if there are no stats recorded, also don't leave stale stats on replaced device - allow extent buffer pages to be allocated as movable, to help page migration - added checks for proper extent buffer release - btrfs.ko code size reduction due to transaction abort call simplifications - several struct size reductions - more auto free conversions - more verbose assertions" * tag 'for-7.2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (130 commits) btrfs: fix use-after-free after relocation failure with concurrent COW btrfs: move WARN_ON on unexpected error in __add_tree_block() btrfs: move locking into btrfs_get_reloc_bg_bytenr() btrfs: lzo: reject compressed segment that overflows the compressed input btrfs: retry faulting in the pages after a zero sized short direct write btrfs: fix incorrect buffered IO fallback for append direct writes btrfs: fix false IO failure after falling back to buffered write btrfs: use verbose assertions in backref.c btrfs: print a message when a missing device re-appears btrfs: do not trim a device which is not writeable btrfs: return real error after lookup failure in btrfs_ioctl_default_subvol() btrfs: use mapping shared locking for reading super block btrfs: use lockless read in nr_cached_objects shrinker callback btrfs: switch local indicator variables to bools btrfs: send: pass bool for pending_move and refs_processed parameters btrfs: use shifts for sectorsize and nodesize btrfs: fix deadlock cloning inline extent when using flushoncommit btrfs: allocate eb-attached btree pages as movable btrfs: add 32-bit compat ioctl for BTRFS_IOC_GET_SUBVOL_INFO btrfs: derive f_fsid from on-disk fsid and dev_t ...
2026-06-14btrfs: Drop WQ_PERCPU from ordered_flags in btrfs_init_workqueues()Nathan Chancellor
After commit 21c05ca88a54 ("workqueue: Add warnings and ensure one among WQ_PERCPU or WQ_UNBOUND is present"), there is a warning from the btrfs-qgroup-rescan workqueue at run time: workqueue: btrfs-qgroup-rescan uses both WQ_PERCPU and WQ_UNBOUND. Dropped WQ_PERCPU, keeping WQ_UNBOUND. WQ_PERCPU is included in ordered_flags after commit 69635d7f4b34 ("fs: WQ_PERCPU added to alloc_workqueue users") and WQ_UNBOUND is set in alloc_ordered_workqueue(), which btrfs_alloc_ordered_workqueue() calls. Drop WQ_PERCPU from ordered_flags, as alloc_ordered_workqueue() notes that only WQ_FREEZABLE and WQ_MEM_RECLAIM are meaningful. Fixes: 69635d7f4b34 ("fs: WQ_PERCPU added to alloc_workqueue users") Fixes: 21c05ca88a54 ("workqueue: Add warnings and ensure one among WQ_PERCPU or WQ_UNBOUND is present") Signed-off-by: Nathan Chancellor <nathan@kernel.org> Reviewed-by: Breno Leitao <leitao@debian.org> Acked-by: Marco Crivellari <marco.crivellari@suse.com> Acked-by: David Sterba <dsterba@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-06-15Merge tag 'vfs-7.2-rc1.super' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs superblock updates from Christian Brauner: "This retires sget(). CIFS plus the two ext4 KUnit tests (extents-test, mballoc-test) were the last in-tree callers, and all three convert cleanly to sget_fc(). That lets sget() and its prototype come out, taking ~60 lines that only existed to be kept in lockstep with sget_fc() on every publish-path change" * tag 'vfs-7.2-rc1.super' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: retire sget() smb: client: convert cifs_smb3_do_mount() to sget_fc() ext4: convert mballoc KUnit test to sget_fc() ext4: convert extents KUnit test to sget_fc()
2026-06-15Merge tag 'vfs-7.2-rc1.inode' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs inode updates from Christian Brauner: "This extends the lockless ->i_count handling. iput() could already decrement any value greater than one locklessly but acquiring a reference always required taking inode->i_lock. Now acquiring a reference is lockless as long as the count was already at least 1, i.e., only the 0->1 and 1->0 transitions take the lock. This avoids the lock for the common cases of nfs calling into the inode hash and btrfs using igrab(). Cleanup-wise icount_read_once() is added to line up with inode_state_read_once() and the open-coded ->i_count loads across the tree are converted, and ihold() is relocated and tidied up. On top of that some stale lock ordering annotations are retired from the inode hash code: iunique() no longer takes the hash lock since the inode hash became RCU-searchable and s_inode_list_lock is no longer taken under the hash lock either" * tag 'vfs-7.2-rc1.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: retire stale lock ordering annotations from inode hash fs: allow lockless ->i_count bumps as long as it does not transition 0->1 fs: relocate and tidy up ihold() fs: add icount_read_once() and stop open-coding ->i_count loads
2026-06-09btrfs: fix use-after-free after relocation failure with concurrent COWFilipe Manana
If we get a failure during relocation, before we update all the extent buffers that have file extent items pointing to extents from the block group being relocated, we can trigger a user-after-free on the reloc control structure (fs_info->reloc_control) if we have a concurrent task that is COWing a subvolume leaf. This happens like this: 1) Relocation of data block group X starts; 2) Relocation changes its state to UPDATE_DATA_PTRS; 3) A task doing a rename for example, COWs leaf A from a subvolume tree and ends up at btrfs_reloc_cow_block() and extracts fs_info->reloc_ctl into a local variable, which then passes to replace_file_extents(); 4) The relocation task gets an error and under the label 'out_put_bg' in btrfs_relocate_block_group() calls free_reloc_control(), which frees the reloc control structure that the rename task is using; 5) The rename task triggers a use-after-free on the reloc control structure that was just freed. Syzbot reported this recently, with the following stack trace: [ 88.389822][ T5325] BTRFS error (device loop0 state A): Transaction aborted (error -5) [ 88.389842][ T5325] BTRFS: error (device loop0 state A) in cleanup_transaction:2067: errno=-5 IO failure [ 88.389864][ T5325] BTRFS info (device loop0 state EA): forced readonly [ 88.392277][ T5324] BTRFS: error (device loop0 state EA) in btrfs_sync_log:3572: errno=-5 IO failure [ 88.396630][ T5325] BTRFS info (device loop0 state EA): balance: ended with status: -5 [ 88.400135][ T5346] ================================================================== [ 88.400148][ T5346] BUG: KASAN: slab-use-after-free in replace_file_extents+0x85f/0x1590 [ 88.400288][ T5346] Read of size 8 at addr ffff888012312010 by task syz.0.0/5346 [ 88.400299][ T5346] [ 88.400306][ T5346] CPU: 0 UID: 0 PID: 5346 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) [ 88.400319][ T5346] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 88.400325][ T5346] Call Trace: [ 88.400331][ T5346] <TASK> [ 88.400336][ T5346] dump_stack_lvl+0xe8/0x150 [ 88.400351][ T5346] print_address_description+0x55/0x1e0 [ 88.400364][ T5346] ? replace_file_extents+0x85f/0x1590 [ 88.400378][ T5346] print_report+0x58/0x70 [ 88.400389][ T5346] kasan_report+0x117/0x150 [ 88.400405][ T5346] ? replace_file_extents+0x85f/0x1590 [ 88.400420][ T5346] replace_file_extents+0x85f/0x1590 [ 88.400440][ T5346] ? __pfx_replace_file_extents+0x10/0x10 [ 88.400452][ T5346] ? update_ref_for_cow+0xa71/0x1270 [ 88.400473][ T5346] btrfs_force_cow_block+0xa4d/0x2450 [ 88.400492][ T5346] ? __pfx_btrfs_force_cow_block+0x10/0x10 [ 88.400508][ T5346] ? __pfx_btrfs_get_32+0x10/0x10 [ 88.400523][ T5346] btrfs_cow_block+0x3c4/0xa90 [ 88.400542][ T5346] push_leaf_left+0x2ac/0x4a0 [ 88.400561][ T5346] split_leaf+0xd16/0x12e0 [ 88.400574][ T5346] ? btrfs_bin_search+0x924/0xc70 [ 88.400592][ T5346] ? __pfx_split_leaf+0x10/0x10 [ 88.400602][ T5346] ? leaf_space_used+0x177/0x1e0 [ 88.400618][ T5346] ? btrfs_leaf_free_space+0x14a/0x2f0 [ 88.400634][ T5346] btrfs_search_slot+0x2641/0x2d20 [ 88.400654][ T5346] ? __pfx_btrfs_search_slot+0x10/0x10 [ 88.400669][ T5346] ? rcu_is_watching+0x15/0xb0 [ 88.400681][ T5346] ? trace_kmem_cache_alloc+0x29/0xe0 [ 88.400694][ T5346] btrfs_insert_empty_items+0x9c/0x190 [ 88.400711][ T5346] btrfs_insert_inode_ref+0x229/0xcb0 [ 88.400724][ T5346] ? __pfx_btrfs_insert_inode_ref+0x10/0x10 [ 88.400736][ T5346] ? __pfx_btrfs_qgroup_convert_reserved_meta+0x10/0x10 [ 88.400751][ T5346] ? btrfs_record_root_in_trans+0x124/0x180 [ 88.400767][ T5346] ? start_transaction+0x8a0/0x1820 [ 88.400778][ T5346] ? btrfs_set_inode_index+0x5e/0x100 [ 88.400787][ T5346] btrfs_rename2+0x17bb/0x40d0 [ 88.400800][ T5346] ? check_noncircular+0xda/0x150 [ 88.400814][ T5346] ? add_lock_to_list+0xc7/0x100 [ 88.400828][ T5346] ? __pfx_btrfs_rename2+0x10/0x10 [ 88.400842][ T5346] ? lockdep_hardirqs_on+0x7a/0x110 [ 88.400901][ T5346] ? lock_acquire+0x221/0x350 [ 88.400915][ T5346] ? down_write_nested+0x174/0x210 [ 88.400931][ T5346] ? __pfx_down_write_nested+0x10/0x10 [ 88.400941][ T5346] ? do_raw_spin_unlock+0x4d/0x210 [ 88.400952][ T5346] ? try_break_deleg+0x5b/0x180 [ 88.400963][ T5346] ? __pfx_btrfs_rename2+0x10/0x10 [ 88.400973][ T5346] vfs_rename+0xa96/0xeb0 [ 88.400992][ T5346] ? __pfx_vfs_rename+0x10/0x10 [ 88.401010][ T5346] ovl_fill_super+0x46b7/0x5e20 [ 88.401030][ T5346] ? __pfx_ovl_fill_super+0x10/0x10 [ 88.401042][ T5346] ? xas_create+0x1902/0x1b90 [ 88.401060][ T5346] ? __pfx___mutex_trylock_common+0x10/0x10 [ 88.401076][ T5346] ? trace_contention_end+0x3d/0x140 [ 88.401094][ T5346] ? shrinker_register+0x124/0x230 [ 88.401111][ T5346] ? __mutex_unlock_slowpath+0x1be/0x6f0 [ 88.401127][ T5346] ? shrinker_register+0x61/0x230 [ 88.401143][ T5346] ? __pfx___mutex_lock+0x10/0x10 [ 88.401158][ T5346] ? __pfx___mutex_unlock_slowpath+0x10/0x10 [ 88.401177][ T5346] ? __raw_spin_lock_init+0x45/0x100 [ 88.401196][ T5346] ? sget_fc+0x962/0xa40 [ 88.401208][ T5346] ? __pfx_set_anon_super_fc+0x10/0x10 [ 88.401222][ T5346] ? __pfx_ovl_fill_super+0x10/0x10 [ 88.401241][ T5346] get_tree_nodev+0xbb/0x150 [ 88.401257][ T5346] vfs_get_tree+0x92/0x2a0 [ 88.401272][ T5346] do_new_mount+0x341/0xd30 [ 88.401283][ T5346] ? apparmor_capable+0x126/0x170 [ 88.401301][ T5346] ? __pfx_do_new_mount+0x10/0x10 [ 88.401311][ T5346] ? ns_capable+0x89/0xe0 [ 88.401322][ T5346] ? path_mount+0x690/0x10e0 [ 88.401333][ T5346] ? user_path_at+0xd4/0x160 [ 88.401346][ T5346] __se_sys_mount+0x31d/0x420 [ 88.401358][ T5346] ? __pfx___se_sys_mount+0x10/0x10 [ 88.401370][ T5346] ? __x64_sys_mount+0x20/0xc0 [ 88.401381][ T5346] ? entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 88.401391][ T5346] do_syscall_64+0x15f/0xf80 [ 88.401403][ T5346] ? trace_irq_disable+0x3b/0x140 [ 88.401413][ T5346] ? clear_bhb_loop+0x40/0x90 [ 88.401421][ T5346] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 88.401429][ T5346] RIP: 0033:0x7fa1ff79ce59 [ 88.401436][ T5346] Code: ff c3 66 (...) [ 88.401443][ T5346] RSP: 002b:00007fa2005affe8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 88.401456][ T5346] RAX: ffffffffffffffda RBX: 00007fa1ffa16180 RCX: 00007fa1ff79ce59 [ 88.401464][ T5346] RDX: 0000200000000100 RSI: 0000200000002240 RDI: 0000000000000000 [ 88.401474][ T5346] RBP: 00007fa1ff832d6f R08: 0000200000000440 R09: 0000000000000000 [ 88.401481][ T5346] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 88.401488][ T5346] R13: 00007fa1ffa16218 R14: 00007fa1ffa16180 R15: 00007ffc734fba78 [ 88.401500][ T5346] </TASK> [ 88.401506][ T5346] [ 88.401510][ T5346] Allocated by task 5325: [ 88.401516][ T5346] kasan_save_track+0x3e/0x80 [ 88.401529][ T5346] __kasan_kmalloc+0x93/0xb0 [ 88.401542][ T5346] __kmalloc_cache_noprof+0x31c/0x660 [ 88.401554][ T5346] btrfs_relocate_block_group+0x217/0xc40 [ 88.401568][ T5346] btrfs_relocate_chunk+0x115/0x820 [ 88.401577][ T5346] __btrfs_balance+0x1db0/0x2ae0 [ 88.401587][ T5346] btrfs_balance+0xaf3/0x11b0 [ 88.401596][ T5346] btrfs_ioctl_balance+0x3d3/0x610 [ 88.401612][ T5346] __se_sys_ioctl+0xfc/0x170 [ 88.401626][ T5346] do_syscall_64+0x15f/0xf80 [ 88.401640][ T5346] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 88.401650][ T5346] [ 88.401653][ T5346] Freed by task 5325: [ 88.401659][ T5346] kasan_save_track+0x3e/0x80 [ 88.401671][ T5346] kasan_save_free_info+0x46/0x50 [ 88.401680][ T5346] __kasan_slab_free+0x5c/0x80 [ 88.401692][ T5346] kfree+0x1c5/0x640 [ 88.401703][ T5346] btrfs_relocate_block_group+0x95d/0xc40 [ 88.401715][ T5346] btrfs_relocate_chunk+0x115/0x820 [ 88.401724][ T5346] __btrfs_balance+0x1db0/0x2ae0 [ 88.401733][ T5346] btrfs_balance+0xaf3/0x11b0 [ 88.401742][ T5346] btrfs_ioctl_balance+0x3d3/0x610 [ 88.401757][ T5346] __se_sys_ioctl+0xfc/0x170 [ 88.401770][ T5346] do_syscall_64+0x15f/0xf80 [ 88.401785][ T5346] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 88.401795][ T5346] [ 88.401798][ T5346] The buggy address belongs to the object at ffff888012312000 [ 88.401798][ T5346] which belongs to the cache kmalloc-2k of size 2048 [ 88.401807][ T5346] The buggy address is located 16 bytes inside of [ 88.401807][ T5346] freed 2048-byte region [ffff888012312000, ffff888012312800) [ 88.401819][ T5346] [ 88.401822][ T5346] The buggy address belongs to the physical page: [ 88.401829][ T5346] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12310 [ 88.401840][ T5346] head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 [ 88.401849][ T5346] flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) [ 88.401860][ T5346] page_type: f5(slab) [ 88.401871][ T5346] raw: 00fff00000000040 ffff88801ac42000 dead000000000100 dead000000000122 [ 88.401881][ T5346] raw: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000 [ 88.401892][ T5346] head: 00fff00000000040 ffff88801ac42000 dead000000000100 dead000000000122 [ 88.401902][ T5346] head: 0000000000000000 0000000800080008 00000000f5000000 0000000000000000 [ 88.401913][ T5346] head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff [ 88.401923][ T5346] head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 [ 88.401929][ T5346] page dumped because: kasan: bad access detected [ 88.401935][ T5346] page_owner tracks the page as allocated [ 88.401941][ T5346] page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 9, tgid 9 (kworker/0:0), ts 83905464494, free_ts 83674944822 [ 88.401961][ T5346] post_alloc_hook+0x231/0x280 [ 88.401975][ T5346] get_page_from_freelist+0x24ba/0x2540 [ 88.401990][ T5346] __alloc_frozen_pages_noprof+0x18d/0x380 [ 88.402004][ T5346] allocate_slab+0x77/0x660 [ 88.402019][ T5346] refill_objects+0x339/0x3d0 [ 88.402033][ T5346] __pcs_replace_empty_main+0x321/0x720 [ 88.402043][ T5346] __kmalloc_node_track_caller_noprof+0x572/0x7b0 [ 88.402055][ T5346] __alloc_skb+0x2c1/0x7d0 [ 88.402067][ T5346] mld_newpack+0x14c/0xc90 [ 88.402080][ T5346] add_grhead+0x5a/0x2a0 [ 88.402093][ T5346] add_grec+0x1452/0x1740 [ 88.402105][ T5346] mld_ifc_work+0x6e6/0xe70 [ 88.402116][ T5346] process_scheduled_works+0xb5d/0x1860 [ 88.402127][ T5346] worker_thread+0xa53/0xfc0 [ 88.402138][ T5346] kthread+0x389/0x470 [ 88.402150][ T5346] ret_from_fork+0x514/0xb70 [ 88.402161][ T5346] page last free pid 5282 tgid 5282 stack trace: [ 88.402168][ T5346] __free_frozen_pages+0xbc7/0xd30 [ 88.402180][ T5346] __slab_free+0x274/0x2c0 [ 88.402191][ T5346] qlist_free_all+0x99/0x100 [ 88.402201][ T5346] kasan_quarantine_reduce+0x148/0x160 [ 88.402211][ T5346] __kasan_slab_alloc+0x22/0x80 [ 88.402221][ T5346] __kmalloc_cache_noprof+0x2ba/0x660 [ 88.402231][ T5346] kernfs_fop_open+0x3f0/0xda0 [ 88.402253][ T5346] do_dentry_open+0x785/0x14e0 [ 88.402262][ T5346] vfs_open+0x3b/0x340 [ 88.402270][ T5346] path_openat+0x2e08/0x3860 [ 88.402281][ T5346] do_file_open+0x23e/0x4a0 [ 88.402292][ T5346] do_sys_openat2+0x113/0x200 [ 88.402300][ T5346] __x64_sys_openat+0x138/0x170 [ 88.402309][ T5346] do_syscall_64+0x15f/0xf80 [ 88.402326][ T5346] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 88.402336][ T5346] [ 88.402339][ T5346] Memory state around the buggy address: [ 88.402345][ T5346] ffff888012311f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 88.402352][ T5346] ffff888012311f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 88.402359][ T5346] >ffff888012312000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 88.402365][ T5346] ^ [ 88.402370][ T5346] ffff888012312080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 88.402380][ T5346] ffff888012312100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 88.402385][ T5346] ================================================================== Fix this by: 1) Making the reloc control structure ref counted; 2) Make revery place that access fs_info->reloc_ctl outside the relocation code, which at the moment it's only replace_file_extents() and btrfs_init_reloc_root(), get a reference count on the structure. There's also btrfs_update_reloc_root() that is called outside the relocation code, but this case is safe because it's only called in the transaction commit path while under the fs_info->reloc_mutex protection, but nevertheless grab a reference to make the code more consistent and avoid false alerts from AI reviews; 3) Add a spinlock to protect fs_info->reloc_ctl, since we can not take the fs_info->reloc_mutex as that would cause a deadlock since that lock is taken in the transaction commit path. That spinlock is taken before setting fs_info->reloc_ctl to an allocated structure, setting it to NULL and reading fs_info->reloc_ctl; 4) Make sure the structure is freed only when its reference count drops to zero. Reported-by: syzbot+0eea49bba18051dea35e@syzkaller.appspotmail.com Link: https://lore.kernel.org/linux-btrfs/6a1df323.bb0696ed.125a22.000a.GAE@google.com/ Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09btrfs: move WARN_ON on unexpected error in __add_tree_block()Filipe Manana
There's no point in having the WARN_ON(1) inside the if statement for the unexpected error. Move it into the if statement's condition, which brings a couple benefits: 1) It marks the branch as unlikely, hinting the compiler to generate better code; 2) The WARN_ON() produces a stack trace after the dumped leaf and error message which can hide that more important information in case we get a truncated dmesg/syslog. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09btrfs: move locking into btrfs_get_reloc_bg_bytenr()Filipe Manana
It does not make sense for the single caller to have the responsability to lock the relocation mutex before calling the function and then have the function to assert the lock is held. As this is a function in relocation.c, move the locking details into it. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09btrfs: lzo: reject compressed segment that overflows the compressed inputWeiming Shi
lzo_decompress_bio() validates each on-disk segment length seg_len only against the workspace cbuf size, not against the compressed input size (compressed_len, the total folio bytes of the bio). A crafted extent can carry a segment whose seg_len passes the cbuf check but runs past the end of the bio, so copy_compressed_segment() walks off the last folio: get_current_folio() then returns the NULL folio from bio_next_folio(), and with CONFIG_BTRFS_ASSERT disabled (default) folio_size(NULL) faults. BUG: KASAN: null-ptr-deref in lzo_decompress_bio (fs/btrfs/lzo.c:383) Read of size 8 at addr 0000000000000000 by task kworker/u8:1/29 Workqueue: btrfs-endio simple_end_io_work kasan_report (mm/kasan/report.c:590) lzo_decompress_bio (fs/btrfs/lzo.c:383) end_bbio_compressed_read (fs/btrfs/compression.c:1065) btrfs_bio_end_io (fs/btrfs/bio.c:135) btrfs_check_read_bio (fs/btrfs/bio.c:180 fs/btrfs/bio.c:285) simple_end_io_work process_one_work worker_thread Reject any segment whose payload would extend beyond compressed_len before copying it, treating it as corruption like the other on-disk validation failures in this function. Reported-by: Xiang Mei <xmei5@asu.edu> Fixes: a6e66e6f8c1b ("btrfs: rework lzo_decompress_bio() to make it subpage compatible") Assisted-by: Claude:claude-opus-4-8 Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Weiming Shi <bestswngs@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09btrfs: retry faulting in the pages after a zero sized short direct writeQu Wenruo
Currently btrfs_direct_write() will not try to fault in the pages, but directly fall back to buffered writes, if the first page of the buffer can not be faulted in. For example, during generic/362 with nodatasum mount option, there is a write at file offset 0, length PAGE_SIZE, and the page is not faulted in. Then we go the following callchain and directly fall back to buffered IO: btrfs_direct_write() |- btrfs_dio_write() |- __iomap_dio_rw() | |- iomap_iter() | | |- btrfs_dio_iomap_begin() | | Now an ordered extent is allocated for the 4K write. | | | |- iomi.status = iomap_dio_iter() | | Where iomap_dio_iter() returned -EFAULT. | | | |- ret = iomap_iter() | | |- btrfs_dio_iomap_end() | | | | return -ENOTBLK | | |- return -ENOTBLK | |- if (ret == -ENOTBLK) { ret = 0; } | Now the return value is reset to 0. | |- ret = iomap_dio_complete() | Since no byte is submitted, @ret is now zero. | |- if (iov_iter_count() > 0 && (ret == -EFAULT || ret > 0)) | @ret is zero, thus not meeting the above retry condition | |- Fallback to buffered Just slightly loosen the condition to allow retry faulting in pages after a zero sized short write. Unlike the previous two bug fixes, this one is not really cause any real bug, but only reducing the chance to do zero-copy direct IO. Thus it doesn't really require stable-CC nor fixes-tag. Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09btrfs: fix incorrect buffered IO fallback for append direct writesQu Wenruo
[BUG] With the previous bug of short direct writes fixed, test case generic/362 (*) still fails with the following error with nodatasum mount option: generic/362 0s ... - output mismatch (see /home/adam/xfstests/results//generic/362.out.bad) - output mismatch (see /home/adam/xfstests/results//generic/362.out.bad) --- tests/generic/362.out 2024-08-24 15:31:37.200000000 +0930 +++ /home/adam/xfstests/results//generic/362.out.bad 2026-05-27 10:13:09.072485767 +0930 @@ -1,2 +1,3 @@ QA output created by 362 +Wrong file size after first write, got 8192 expected 4096 Silence is golden ... *: If the test case has been executed before with default data checksum, the failure will not reproduce. Need the following fix to make it reliably reproducible: https://lore.kernel.org/linux-btrfs/20260528111659.87113-1-wqu@suse.com/ [CAUSE] Inside btrfs_dio_iomap_begin() for a direct write, we increase the isize if it's beyond the current isize. But if the direct io finished short, we do not revert the isize to the previous value nor to the short write end. Then if we need to fall back to buffered writes, and the write has IOCB_APPEND flag, then the buffered write will be positioned at the incorrect isize. The call chain looks like this: btrfs_direct_write(pos=0, length=4K) |- __iomap_dio_rw() | |- iomap_iter() | | |- btrfs_dio_iomap_begin() | | |- btrfs_get_blocks_direct_write() | | |- i_size_write() | | Which updates the isize to the write end (4K). | | | |- iomap_dio_iter() | | Failed with -EFAULT on the first page. | | | |- iomap_iter() | | |- btrfs_dio_iomap_end() | | Detects a short write, return -ENOTBLK | |- if (ret == -ENOTBLK) { ret = 0;} | Which resets the return value. | |- ret = iomap_dio_complet() | Which returns 0. | |- btrfs_buffered_write(iocb, from); |- generic_write_checks() |- iocb->ki_pos = i_size_read() Which is still the new size (4K), other than the original isize 0. [FIX] Introduce the following btrfs_dio_data members: - old_isize - updated_isize If the direct write has enlarged the isize. Then if we got a short write, and btrfs_dio_data::updated_isize is set, revert to the correct isize based on old_isize and current file position. And here we call i_size_write() without holding an extent lock, which is a very special case that we're safe to do: - Only a single writer can be enlarging isize Enlarging isize will take the exclusive inode lock. - Buffered readers need to wait for the OE we're holding Buffered readers will lock extent and wait for OE of the folio range. Sometimes we can skip the OE wait, but since all page cache is invalidated, the OE wait can not be skipped. But I do not think this is the most elegant solution, nor covers all cases. E.g. if the bio is submitted but IO failed, we are unable to do the revert. I believe the more elegant one would be extend the EXTENT_DIO_LOCKED lifespan for direct writes, so that we can update the isize when a write beyond EOF finished successfully. However that change is too huge for a small bug fix. So only implement the minimal partial fix for now. [REASON FOR NO FIXES TAG] The bug is again very old, before commit f85781fb505e ("btrfs: switch to iomap for direct IO") we are already increasing isize without a proper rollback for short writes. Thus only a CC to stable. CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09btrfs: fix false IO failure after falling back to buffered writeQu Wenruo
[BUG] The test case generic/362 will fail with "nodatasum" mount option (*): MOUNT_OPTIONS -- -o nodatasum /dev/mapper/test-scratch1 /mnt/scratch generic/362 0s ... - output mismatch (see /home/adam/xfstests/results//generic/362.out.bad) --- tests/generic/362.out 2024-08-24 15:31:37.200000000 +0930 +++ /home/adam/xfstests/results//generic/362.out.bad 2026-05-27 10:21:17.574771567 +0930 @@ -1,2 +1,3 @@ QA output created by 362 +First write failed: Input/output error Silence is golden ... *: If the test case has been executed before with default data checksum, the failure will not reproduce. Need the following fix to make it reliably reproducible: https://lore.kernel.org/linux-btrfs/20260528111659.87113-1-wqu@suse.com/ [CAUSE] Inside __iomap_dio_rw(), the -EFAULT/-ENOTBLK error is not directly returned. Thus we never got an error pointer from __iomap_dio_rw(). The call chain looks like this: btrfs_direct_write() |- btrfs_dio_write() |- __iomap_dio_rw() | |- iomap_iter() | | |- btrfs_dio_iomap_begin() | | Now an ordered extent is allocated for the 4K write. | | | |- iomi.status = iomap_dio_iter() | | Where iomap_dio_iter() returned -EFAULT. | | | |- ret = iomap_iter() | | |- btrfs_dio_iomap_end() | | | |- btrfs_finish_ordered_extent(uptodate = false) | | | | |- can_finish_ordered_extent() | | | | |- btrfs_mark_ordered_extent_error() | | | | |- mapping_set_error() | | | | Now the address space is marked error. | | | | return -ENOTBLK | | |- return -ENOTBLK | |- if (ret == -ENOTBLK) { ret = 0; } | Now the return value is reset to 0. | Thus no error pointer will be returned. | |- ret = iomap_dio_complete() | Since no byte is submitted, @ret is 0. | |- Fallback to buffered IO | And the buffered write finished without error | |- filemap_fdatawait_range() |- filemap_check_errors() The previous error is recorded, thus an error is returned However the buffered write is properly submitted and finished, the error is from the btrfs_finish_ordered_extent() call with @uptodate = false. [FIX] When a short dio write happened, any range that is submitted will have btrfs_extract_ordered_extent() to be called, thus the submitted range will always have an OE just covering the submitted range. The remaining OE range is never submitted, thus they should be treated as truncated, not an error. So that we can properly reclaim and not insert an unnecessary file extent item, without marking the mapping as error. Extract a helper, btrfs_mark_ordered_extent_truncated(), and utilize that helper to mark the direct IO ordered extent as truncated, so it won't cause failure for the later buffered fallback. [REASON FOR NO FIXES TAG] The bug itself is pretty old, at commit f85781fb505e ("btrfs: switch to iomap for direct IO") we're already passing @uptodate=false finishing the OE. But at that time OE with IOERR won't call mapping_set_error(), so it's not exposed. Later commit d61bec08b904 ("btrfs: mark ordered extent and inode with error if we fail to finish") finally exposed the bug, but that commit is doing a correct job, not the root cause. Anyway the bug is very old, dating back to 5.1x days, thus only CC to stable. CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Boris Burkov <boris@bur.io> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09btrfs: use verbose assertions in backref.cFilipe Manana
While debugging a relocation issue I hit an assertion in backref.c but it was not super useful, since it could not tell what was the unexpected value that triggered the assertion. The stack trace was this: [583246.338097] assertion failed: !cache->nr_nodes, in fs/btrfs/backref.c:3158 [583246.339588] ------------[ cut here ]------------ [583246.340573] kernel BUG at fs/btrfs/backref.c:3158! [583246.342075] Oops: invalid opcode: 0000 [#1] SMP PTI [583246.343294] CPU: 5 UID: 0 PID: 677957 Comm: btrfs Not tainted 7.1.0-rc4-btrfs-next-234+ #1 PREEMPT(full) [583246.345715] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014 [583246.348694] RIP: 0010:btrfs_backref_release_cache.cold+0x61/0x84 [btrfs] [583246.350759] Code: 90 d5 7c (...) [583246.354923] RSP: 0018:ffffd4fc88c93ad8 EFLAGS: 00010246 [583246.355982] RAX: 000000000000003e RBX: ffff8dec90d97020 RCX: 0000000000000000 [583246.357459] RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00000000ffffffff [583246.359517] RBP: ffff8dec8eeb78c0 R08: 0000000000000000 R09: 3fffffffffefffff [583246.361180] R10: ffffd4fc88c93970 R11: 0000000000000003 R12: ffff8decd21f3470 [583246.363184] R13: 00000000fffffffe R14: ffff8decd21f3000 R15: ffff8decd21f3000 [583246.364666] FS: 00007f9a51751400(0000) GS:ffff8df3f4255000(0000) knlGS:0000000000000000 [583246.366287] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [583246.367443] CR2: 00007f9a518ed8f5 CR3: 00000004467c8002 CR4: 0000000000370ef0 [583246.368969] Call Trace: [583246.369541] <TASK> [583246.370040] relocate_block_group+0xf2/0x520 [btrfs] [583246.371243] btrfs_relocate_block_group+0x9a9/0x22e0 [btrfs] [583246.372443] ? preempt_count_add+0x47/0xa0 [583247.532978] ? btrfs_tree_read_lock_nested+0x19/0x90 [btrfs] [583247.534520] ? mutex_lock+0x1a/0x40 [583247.602233] ? btrfs_scrub_pause+0x2e/0x120 [btrfs] [583247.603543] btrfs_relocate_chunk+0x3b/0x1a0 [btrfs] [583247.604893] btrfs_balance+0x9d5/0x1920 [btrfs] [583247.606189] ? preempt_count_add+0x69/0xa0 [583247.607030] btrfs_ioctl+0x260c/0x2a20 [btrfs] [583247.608015] ? __memcg_slab_free_hook+0x156/0x1a0 [583247.636971] __x64_sys_ioctl+0x92/0xe0 [583247.679247] do_syscall_64+0x60/0xf20 [583247.753297] ? clear_bhb_loop+0x60/0xb0 [583247.756321] entry_SYSCALL_64_after_hwframe+0x76/0x7e [583247.787018] RIP: 0033:0x7f9a5186a8db [583247.787787] Code: 00 48 89 (...) [583247.791410] RSP: 002b:00007fff2ffa6ac0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [583247.792897] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f9a5186a8db [583247.794319] RDX: 00007fff2ffa6bb0 RSI: 00000000c4009420 RDI: 0000000000000003 [583247.795714] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [583247.797149] R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff2ffa903f [583247.798685] R13: 00007fff2ffa6bb0 R14: 0000000000000002 R15: 0000000000000002 [583247.800136] </TASK> So update all simple assertions in backref.c to print out the values when they aren't testing simple boolean conditions. Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2026-06-09btrfs: print a message when a missing device re-appearsQu Wenruo
There is a bug report that fstrim crashed, and that crash is eventually pinned down to a missing device which re-appeared and screwed up callers that only checks BTRFS_DEV_STATE_MISSING, but not BTRFS_DEV_STATE_WRITEABLE nor device->bdev. A missing device re-appearing can be very tricky, as for now it will result in a device without WRITEABLE or MISSING flag, and still no bdev pointer. As the first step to enhance handling of such re-appearing missing devices, add a dmesg output when a missing device re-appeared. Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>