bcachefs (loop0): Detected missing backpointers in bucket 34, now have 1/128 with missing running recovery pass check_extents_to_backpointers (17), currently at set_fs_needs_rebalance (42) bcachefs (loop0): Detected missing backpointers in bucket 34, now have 1/128 with missing running recovery pass check_extents_to_backpointers (17), currently at check_extents_to_backpointers (17) ================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: slab-use-after-free in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] BUG: KASAN: slab-use-after-free in bch2_bucket_bitmap_test fs/bcachefs/backpointers.h:194 [inline] BUG: KASAN: slab-use-after-free in bch2_bucket_is_movable fs/bcachefs/movinggc.c:78 [inline] BUG: KASAN: slab-use-after-free in bch2_copygc_get_buckets fs/bcachefs/movinggc.c:157 [inline] BUG: KASAN: slab-use-after-free in bch2_copygc+0x105d/0x4510 fs/bcachefs/movinggc.c:221 Read of size 8 at addr ffff8880435b34c0 by task bch-copygc/loop/5345 CPU: 0 UID: 0 PID: 5345 Comm: bch-copygc/loop Not tainted 6.16.0-rc7-syzkaller-00120-g5f33ebd2018c #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] bch2_bucket_bitmap_test fs/bcachefs/backpointers.h:194 [inline] bch2_bucket_is_movable fs/bcachefs/movinggc.c:78 [inline] bch2_copygc_get_buckets fs/bcachefs/movinggc.c:157 [inline] bch2_copygc+0x105d/0x4510 fs/bcachefs/movinggc.c:221 bch2_copygc_thread+0x97a/0xe00 fs/bcachefs/movinggc.c:409 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5345: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4328 [inline] __kvmalloc_node_noprof+0x30d/0x5f0 mm/slub.c:5015 kvmalloc_array_node_noprof include/linux/slab.h:1065 [inline] bch2_bucket_bitmap_set+0x9a/0x1a0 fs/bcachefs/backpointers.c:1351 check_bucket_backpointer_mismatch+0x1bdf/0x23a0 fs/bcachefs/backpointers.c:964 check_bucket_backpointer_pos_mismatch fs/bcachefs/backpointers.c:1193 [inline] bch2_check_bucket_backpointer_mismatch+0x36c/0x690 fs/bcachefs/backpointers.c:1205 __bch2_move_data_phys+0x17a7/0x1c50 fs/bcachefs/move.c:922 bch2_evacuate_bucket+0x228/0x3a0 fs/bcachefs/move.c:1082 bch2_copygc+0x3be3/0x4510 fs/bcachefs/movinggc.c:234 bch2_copygc_thread+0x97a/0xe00 fs/bcachefs/movinggc.c:409 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the object at ffff8880435b34c0 which belongs to the cache kmalloc-16 of size 16 The buggy address is located 0 bytes inside of freed 16-byte region [ffff8880435b34c0, ffff8880435b34d0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x435b3 anon flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000000 ffff88801a441640 0000000000000000 dead000000000001 raw: 0000000000000000 0000000080800080 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 54, tgid 54 (kworker/0:2), ts 60929069981, free_ts 60928958150 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704 prep_new_page mm/page_alloc.c:1712 [inline] get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3669 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419 alloc_slab_page mm/slub.c:2451 [inline] allocate_slab+0x8a/0x3b0 mm/slub.c:2619 new_slab mm/slub.c:2673 [inline] ___slab_alloc+0xbfc/0x1480 mm/slub.c:3859 __slab_alloc mm/slub.c:3949 [inline] __slab_alloc_node mm/slub.c:4024 [inline] slab_alloc_node mm/slub.c:4185 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_noprof+0x305/0x4f0 mm/slub.c:4340 kmalloc_noprof include/linux/slab.h:909 [inline] kmalloc_array_noprof include/linux/slab.h:948 [inline] drm_atomic_helper_dirtyfb+0x159/0xee0 drivers/gpu/drm/drm_damage_helper.c:141 drm_fbdev_shmem_helper_fb_dirty+0x160/0x2f0 drivers/gpu/drm/drm_fbdev_shmem.c:117 drm_fb_helper_fb_dirty drivers/gpu/drm/drm_fb_helper.c:379 [inline] drm_fb_helper_damage_work+0x224/0x710 drivers/gpu/drm/drm_fb_helper.c:402 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 page last free pid 5229 tgid 5229 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1248 [inline] __free_frozen_pages+0xc71/0xe70 mm/page_alloc.c:2706 rcu_do_batch kernel/rcu/tree.c:2576 [inline] rcu_core+0xca8/0x1710 kernel/rcu/tree.c:2832 handle_softirqs+0x286/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 Memory state around the buggy address: ffff8880435b3380: 00 00 fc fc 00 00 fc fc fa fb fc fc fa fb fc fc ffff8880435b3400: 00 04 fc fc 00 06 fc fc fa fb fc fc fa fb fc fc >ffff8880435b3480: fa fb fc fc fa fb fc fc fb fb fc fc 00 00 fc fc ^ ffff8880435b3500: 00 04 fc fc 00 07 fc fc 00 06 fc fc 00 05 fc fc ffff8880435b3580: 00 00 fc fc 00 02 fc fc 00 04 fc fc 00 05 fc fc ==================================================================