BTRFS info (device loop2): clearing compat-ro feature flag for FREE_SPACE_TREE (0x1)
BTRFS info (device loop2): clearing compat-ro feature flag for FREE_SPACE_TREE_VALID (0x2)
==================================================================
BUG: KASAN: use-after-free in do_trace_event_raw_event_btrfs_delayed_tree_ref include/trace/events/btrfs.h:865 [inline]
BUG: KASAN: use-after-free in trace_event_raw_event_btrfs_delayed_tree_ref+0x168/0x3f4 include/trace/events/btrfs.h:844
Read of size 8 at addr ffff0000ccaf78b0 by task syz.2.2132/9328

CPU: 1 PID: 9328 Comm: syz.2.2132 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026
Call trace:
 dump_backtrace+0x1c4/0x1f0 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106
 print_address_description+0x88/0x218 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:420
 kasan_report+0xa8/0xfc mm/kasan/report.c:524
 __asan_report_load8_noabort+0x2c/0x38 mm/kasan/report_generic.c:351
 do_trace_event_raw_event_btrfs_delayed_tree_ref include/trace/events/btrfs.h:865 [inline]
 trace_event_raw_event_btrfs_delayed_tree_ref+0x168/0x3f4 include/trace/events/btrfs.h:844
 __traceiter_add_delayed_tree_ref+0x90/0xe8 include/trace/events/btrfs.h:887
 trace_add_delayed_tree_ref include/trace/events/btrfs.h:887 [inline]
 btrfs_add_delayed_tree_ref+0xc38/0xd28 fs/btrfs/delayed-ref.c:982
 btrfs_free_tree_block+0x268/0xa38 fs/btrfs/extent-tree.c:3299
 btrfs_force_cow_block+0xac0/0x18c0 fs/btrfs/ctree.c:527
 btrfs_cow_block+0x2e0/0x71c fs/btrfs/ctree.c:623
 btrfs_search_slot+0xa48/0x2380 fs/btrfs/ctree.c:-1
 btrfs_insert_empty_items+0xa4/0x180 fs/btrfs/ctree.c:4185
 btrfs_insert_empty_item fs/btrfs/ctree.h:3073 [inline]
 btrfs_insert_orphan_item+0x13c/0x1cc fs/btrfs/orphan.c:24
 btrfs_orphan_add+0x70/0x1bc fs/btrfs/inode.c:3738
 btrfs_unlink+0x230/0x300 fs/btrfs/inode.c:4520
 vfs_unlink+0x2e0/0x4f4 fs/namei.c:4330
 do_unlinkat+0x318/0x504 fs/namei.c:4398
 __do_sys_unlinkat fs/namei.c:4441 [inline]
 __se_sys_unlinkat fs/namei.c:4434 [inline]
 __arm64_sys_unlinkat+0xe0/0xfc fs/namei.c:4434
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x200/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Allocated by task 9328:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x70/0x88 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x74/0x430 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 slab_alloc mm/slub.c:3367 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3374 [inline]
 kmem_cache_alloc+0x234/0x310 mm/slub.c:3383
 btrfs_add_delayed_tree_ref+0x160/0xd28 fs/btrfs/delayed-ref.c:926
 btrfs_free_tree_block+0x268/0xa38 fs/btrfs/extent-tree.c:3299
 btrfs_force_cow_block+0xac0/0x18c0 fs/btrfs/ctree.c:527
 btrfs_cow_block+0x2e0/0x71c fs/btrfs/ctree.c:623
 btrfs_search_slot+0xa48/0x2380 fs/btrfs/ctree.c:-1
 btrfs_insert_empty_items+0xa4/0x180 fs/btrfs/ctree.c:4185
 btrfs_insert_empty_item fs/btrfs/ctree.h:3073 [inline]
 btrfs_insert_orphan_item+0x13c/0x1cc fs/btrfs/orphan.c:24
 btrfs_orphan_add+0x70/0x1bc fs/btrfs/inode.c:3738
 btrfs_unlink+0x230/0x300 fs/btrfs/inode.c:4520
 vfs_unlink+0x2e0/0x4f4 fs/namei.c:4330
 do_unlinkat+0x318/0x504 fs/namei.c:4398
 __do_sys_unlinkat fs/namei.c:4441 [inline]
 __se_sys_unlinkat fs/namei.c:4434 [inline]
 __arm64_sys_unlinkat+0xe0/0xfc fs/namei.c:4434
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x200/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Freed by task 9:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:53
 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516
 ____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:237
 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:245
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x16c/0x1e8 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 kmem_cache_free+0x118/0x318 mm/slub.c:3709
 btrfs_put_delayed_ref+0x18c/0x250 fs/btrfs/delayed-ref.h:-1
 btrfs_run_delayed_refs_for_head fs/btrfs/extent-tree.c:1979 [inline]
 __btrfs_run_delayed_refs+0x1400/0x3374 fs/btrfs/extent-tree.c:2033
 btrfs_run_delayed_refs+0x11c/0x474 fs/btrfs/extent-tree.c:2164
 btrfs_commit_transaction+0x1e4/0x28e4 fs/btrfs/transaction.c:2191
 btrfs_qgroup_rescan_worker+0x14cc/0x156c fs/btrfs/qgroup.c:3423
 btrfs_work_helper+0x328/0xcbc fs/btrfs/async-thread.c:280
 process_one_work+0x7e4/0x13bc kernel/workqueue.c:2292
 worker_thread+0x8cc/0xfe8 kernel/workqueue.c:2439
 kthread+0x254/0x2e0 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850

The buggy address belongs to the object at ffff0000ccaf7888
 which belongs to the cache btrfs_delayed_tree_ref of size 104
The buggy address is located 40 bytes inside of
 104-byte region [ffff0000ccaf7888, ffff0000ccaf78f0)

The buggy address belongs to the physical page:
page:000000003bc07a17 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff0000ccaf7348 pfn:0x10caf7
flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000200 0000000000000000 dead000000000122 ffff0000ca57f980
raw: ffff0000ccaf7348 0000000080180010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000ccaf7780: fb fb fb fb fc fc fc fc fc fc fc fc fa fb fb fb
 ffff0000ccaf7800: fb fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc
>ffff0000ccaf7880: fc fa fb fb fb fb fb fb fb fb fb fb fb fb fc fc
                                     ^
 ffff0000ccaf7900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff0000ccaf7980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================