================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x114/0x764c kernel/locking/lockdep.c:4918 Read of size 8 at addr ffff0000d2d55cf0 by task segctord/4508 CPU: 1 PID: 4508 Comm: segctord Not tainted 6.1.54-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x174/0x4c0 mm/kasan/report.c:395 kasan_report+0xd4/0x130 mm/kasan/report.c:495 __asan_report_load8_noabort+0x2c/0x38 mm/kasan/report_generic.c:351 __lock_acquire+0x114/0x764c kernel/locking/lockdep.c:4918 lock_acquire+0x26c/0x7cc kernel/locking/lockdep.c:5661 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x6c/0xb4 kernel/locking/spinlock.c:162 try_to_wake_up+0xb4/0xe60 kernel/sched/core.c:4108 wake_up_process+0x18/0x24 kernel/sched/core.c:4358 nilfs_construction_timeout+0x40/0x50 fs/nilfs2/segment.c:2442 call_timer_fn+0x1c0/0xa1c kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers+0x554/0x718 kernel/time/timer.c:1790 run_timer_softirq+0x7c/0x114 kernel/time/timer.c:1803 __do_softirq+0x30c/0xea0 kernel/softirq.c:571 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:79 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:889 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:84 invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0x28c/0x534 kernel/softirq.c:650 irq_exit_rcu+0x14/0x84 kernel/softirq.c:662 __el1_irq arch/arm64/kernel/entry-common.c:472 [inline] el1_interrupt+0x38/0x68 arch/arm64/kernel/entry-common.c:486 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:577 arch_local_irq_restore arch/arm64/include/asm/irqflags.h:122 [inline] console_emit_next_record+0x94c/0xb40 kernel/printk/printk.c:2737 console_unlock+0x294/0x6f8 kernel/printk/printk.c:2860 vprintk_emit+0x14c/0x2e4 kernel/printk/printk.c:2268 vprintk_default+0xa0/0xe4 kernel/printk/printk.c:2279 vprintk+0x218/0x2f0 kernel/printk/printk_safe.c:50 _printk+0xdc/0x128 kernel/printk/printk.c:2289 __nilfs_msg+0x2e4/0x37c fs/nilfs2/super.c:78 nilfs_segctor_thread+0x1cc/0xd74 fs/nilfs2/segment.c:2585 kthread+0x250/0x2d8 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 Allocated by task 2: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:52 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505 __kasan_slab_alloc+0x74/0x8c mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x74/0x458 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] kmem_cache_alloc_node+0x258/0x3b4 mm/slub.c:3443 alloc_task_struct_node kernel/fork.c:171 [inline] dup_task_struct+0x74/0x7dc kernel/fork.c:972 copy_process+0x530/0x38d0 kernel/fork.c:2090 kernel_clone+0x1d8/0x98c kernel/fork.c:2674 kernel_thread+0x128/0x1a8 kernel/fork.c:2734 create_kthread kernel/kthread.c:399 [inline] kthreadd+0x49c/0x674 kernel/kthread.c:746 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860 Freed by task 21: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:52 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516 ____kasan_slab_free+0x144/0x1c0 mm/kasan/common.c:236 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook mm/slub.c:1750 [inline] slab_free mm/slub.c:3661 [inline] kmem_cache_free+0x2f0/0x588 mm/slub.c:3683 free_task_struct kernel/fork.c:176 [inline] free_task+0xe8/0x14c kernel/fork.c:563 __put_task_struct+0x178/0x210 kernel/fork.c:851 put_task_struct include/linux/sched/task.h:119 [inline] delayed_put_task_struct+0x140/0x404 kernel/exit.c:225 rcu_do_batch kernel/rcu/tree.c:2251 [inline] rcu_core+0x878/0x1c10 kernel/rcu/tree.c:2511 rcu_core_si+0x10/0x1c kernel/rcu/tree.c:2528 __do_softirq+0x30c/0xea0 kernel/softirq.c:571 Last potentially related work creation: kasan_save_stack+0x40/0x70 mm/kasan/common.c:45 __kasan_record_aux_stack+0xcc/0xe8 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0x14/0x20 mm/kasan/generic.c:496 call_rcu+0xfc/0xa40 kernel/rcu/tree.c:2799 put_task_struct_rcu_user+0x68/0xcc kernel/exit.c:231 finish_task_switch+0x5c4/0x624 kernel/sched/core.c:5154 context_switch kernel/sched/core.c:5244 [inline] __schedule+0xee8/0x1c98 kernel/sched/core.c:6554 schedule+0xc4/0x170 kernel/sched/core.c:6630 schedule_timeout+0x1d8/0x344 kernel/time/timer.c:1935 io_schedule_timeout+0x98/0x130 kernel/sched/core.c:8770 do_wait_for_common+0x30c/0x468 kernel/sched/completion.c:85 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common_io kernel/sched/completion.c:123 [inline] wait_for_completion_io_timeout+0x50/0x74 kernel/sched/completion.c:191 submit_bio_wait+0x15c/0x210 block/bio.c:1326 blkdev_issue_flush+0xb8/0x104 block/blk-flush.c:467 nilfs_flush_device fs/nilfs2/the_nilfs.h:380 [inline] nilfs_sync_fs+0x4f4/0x64c fs/nilfs2/super.c:536 sync_filesystem+0x1a0/0x218 fs/sync.c:66 generic_shutdown_super+0x70/0x328 fs/super.c:474 kill_block_super+0x70/0xdc fs/super.c:1459 deactivate_locked_super+0xac/0x124 fs/super.c:332 deactivate_super+0xf0/0x110 fs/super.c:363 cleanup_mnt+0x394/0x41c fs/namespace.c:1186 __cleanup_mnt+0x20/0x30 fs/namespace.c:1193 task_work_run+0x240/0x2f0 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x2144/0x3470 arch/arm64/kernel/signal.c:1132 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x9c/0x168 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581 Second to last potentially related work creation: kasan_save_stack+0x40/0x70 mm/kasan/common.c:45 __kasan_record_aux_stack+0xcc/0xe8 mm/kasan/generic.c:486 kasan_record_aux_stack_noalloc+0x14/0x20 mm/kasan/generic.c:496 call_rcu+0xfc/0xa40 kernel/rcu/tree.c:2799 release_task+0x1468/0x1550 wait_task_zombie kernel/exit.c:1205 [inline] wait_consider_task+0x15fc/0x2754 kernel/exit.c:1432 do_wait_thread kernel/exit.c:1495 [inline] do_wait+0x314/0xb40 kernel/exit.c:1612 kernel_wait4+0x24c/0x3d8 kernel/exit.c:1775 __do_sys_wait4 kernel/exit.c:1803 [inline] __se_sys_wait4 kernel/exit.c:1799 [inline] __arm64_sys_wait4+0x11c/0x2a0 kernel/exit.c:1799 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x168 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:581 The buggy address belongs to the object at ffff0000d2d55340 which belongs to the cache task_struct of size 6848 The buggy address is located 2480 bytes inside of 6848-byte region [ffff0000d2d55340, ffff0000d2d56e00) The buggy address belongs to the physical page: page:000000004f067671 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x112d50 head:000000004f067671 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 fffffc00034aec00 dead000000000002 ffff0000c03d4f00 raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000d2d55b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000d2d55c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000d2d55c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000d2d55d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000d2d55d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================