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_inodes (28) ================================================================== 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 ffff88803f4ecb20 by task bch-copygc/loop/5379 CPU: 0 UID: 0 PID: 5379 Comm: bch-copygc/loop Not tainted syzkaller #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+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5379: 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:388 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4365 [inline] __kvmalloc_node_noprof+0x30d/0x5f0 mm/slub.c:5052 kvmalloc_array_node_noprof include/linux/slab.h:1065 [inline] bch2_bucket_bitmap_set+0x9a/0x1d0 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+0x70e/0x8a0 kernel/kthread.c:463 ret_from_fork+0x3f9/0x770 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 ffff88803f4ecb20 which belongs to the cache kmalloc-16 of size 16 The buggy address is located 0 bytes inside of freed 16-byte region [ffff88803f4ecb20, ffff88803f4ecb30) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3f4ec flags: 0x4fff00000000000(node=1|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 04fff00000000000 ffff88801a441640 dead000000000122 0000000000000000 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 0xd2800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5360, tgid 5359 (syz.0.0), ts 97991800784, free_ts 97986265130 create_dummy_stack mm/page_owner.c:94 [inline] register_dummy_stack+0x89/0xe0 mm/page_owner.c:100 init_page_owner+0x2e/0x620 mm/page_owner.c:118 invoke_init_callbacks mm/page_ext.c:148 [inline] page_ext_init+0x511/0x550 mm/page_ext.c:486 mm_core_init+0x56/0x70 mm/mm_init.c:2789 page last free pid 5360 tgid 5359 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc4/0xd30 mm/page_alloc.c:2895 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xcab/0x1770 kernel/rcu/tree.c:2861 handle_softirqs+0x283/0x870 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: ffff88803f4eca00: 00 00 fc fc 00 00 fc fc 00 00 fc fc 00 00 fc fc ffff88803f4eca80: fa fb fc fc fa fb fc fc 00 00 fc fc fa fb fc fc >ffff88803f4ecb00: fa fb fc fc fb fb fc fc 00 00 fc fc 00 00 fc fc ^ ffff88803f4ecb80: fa fb fc fc fa fb fc fc fa fb fc fc fa fb fc fc ffff88803f4ecc00: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================