================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x77/0x1f80 kernel/locking/lockdep.c:4919 Read of size 8 at addr ffff888028e027d8 by task swapper/0/0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.1.82-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15f/0x4f0 mm/kasan/report.c:395 kasan_report+0x136/0x160 mm/kasan/report.c:495 __lock_acquire+0x77/0x1f80 kernel/locking/lockdep.c:4919 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 try_to_wake_up+0xad/0x12e0 kernel/sched/core.c:4112 call_timer_fn+0x1ad/0x6b0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers+0x67c/0x890 kernel/time/timer.c:1790 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:650 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:130 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:113 [inline] RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:572 Code: c6 f6 f6 48 83 e3 08 0f 85 0b 01 00 00 4c 8d 74 24 20 e8 84 82 fd f6 0f 1f 44 00 00 e8 2a c2 f6 f6 0f 00 2d 33 7b b3 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 ab 37 4e f7 RSP: 0018:ffffffff8ce07b20 EFLAGS: 000002d3 RAX: ffffffff8a93c166 RBX: 0000000000000000 RCX: ffffffff8cebd800 RDX: 0000000000000000 RSI: ffffffff8aebee40 RDI: ffffffff8b3d2b40 RBP: ffffffff8ce07bb0 R08: ffffffff8a93c148 R09: fffffbfff19d7b01 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff19c0f64 R13: ffff888017a7e004 R14: ffffffff8ce07b40 R15: dffffc0000000000 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:709 cpuidle_enter_state+0x516/0xf80 drivers/cpuidle/cpuidle.c:239 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:356 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x3ce/0x680 kernel/sched/idle.c:303 cpu_startup_entry+0x3d/0x60 kernel/sched/idle.c:401 rest_init+0x2da/0x300 init/main.c:731 arch_call_rest_init+0xa/0xa init/main.c:891 start_kernel+0x496/0x53f init/main.c:1138 secondary_startup_64_no_verify+0xcf/0xdb Allocated by task 2: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] kmem_cache_alloc_node+0x136/0x310 mm/slub.c:3443 alloc_task_struct_node kernel/fork.c:171 [inline] dup_task_struct+0x57/0x6d0 kernel/fork.c:980 copy_process+0x637/0x4060 kernel/fork.c:2098 kernel_clone+0x222/0x920 kernel/fork.c:2682 kernel_thread+0x152/0x1d0 kernel/fork.c:2742 create_kthread kernel/kthread.c:399 [inline] kthreadd+0x596/0x760 kernel/kthread.c:746 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:307 Freed by task 17320: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 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+0x292/0x510 mm/slub.c:3683 rcu_do_batch kernel/rcu/tree.c:2296 [inline] rcu_core+0xad4/0x17e0 kernel/rcu/tree.c:2556 __do_softirq+0x2e9/0xa4c kernel/softirq.c:571 Last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2844 context_switch kernel/sched/core.c:5248 [inline] __schedule+0x1435/0x4550 kernel/sched/core.c:6558 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6727 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6751 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] nilfs_segctor_kill_thread fs/nilfs2/segment.c:2678 [inline] nilfs_segctor_destroy fs/nilfs2/segment.c:2761 [inline] nilfs_detach_log_writer+0x25e/0xbd0 fs/nilfs2/segment.c:2850 nilfs_put_super+0x49/0x150 fs/nilfs2/super.c:498 generic_shutdown_super+0x130/0x340 fs/super.c:501 kill_block_super+0x7a/0xe0 fs/super.c:1459 deactivate_locked_super+0xa0/0x110 fs/super.c:332 cleanup_mnt+0x490/0x520 fs/namespace.c:1186 task_work_run+0x246/0x300 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:171 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:297 do_syscall_64+0x49/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x63/0xcd Second to last potentially related work creation: kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2844 release_task+0x1637/0x16d0 wait_task_zombie kernel/exit.c:1205 [inline] wait_consider_task+0x1a64/0x2e90 kernel/exit.c:1432 do_wait_thread kernel/exit.c:1495 [inline] do_wait+0x32b/0xb80 kernel/exit.c:1612 kernel_wait4+0x29e/0x3e0 kernel/exit.c:1775 __do_sys_wait4 kernel/exit.c:1803 [inline] __se_sys_wait4 kernel/exit.c:1799 [inline] __x64_sys_wait4+0x130/0x1e0 kernel/exit.c:1799 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff888028e01dc0 which belongs to the cache task_struct of size 7360 The buggy address is located 2584 bytes inside of 7360-byte region [ffff888028e01dc0, ffff888028e03a80) The buggy address belongs to the physical page: page:ffffea0000a38000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28e00 head:ffffea0000a38000 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff8880591f1681 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00007f3800 dead000000000003 ffff888140008500 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff8880591f1681 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2, tgid 2 (kthreadd), ts 18243969379, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2513 prep_new_page mm/page_alloc.c:2520 [inline] get_page_from_freelist+0x31a1/0x3320 mm/page_alloc.c:4279 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5545 alloc_slab_page+0x6a/0x150 mm/slub.c:1794 allocate_slab mm/slub.c:1939 [inline] new_slab+0x84/0x2d0 mm/slub.c:1992 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180 __slab_alloc mm/slub.c:3279 [inline] slab_alloc_node mm/slub.c:3364 [inline] kmem_cache_alloc_node+0x1cf/0x310 mm/slub.c:3443 alloc_task_struct_node kernel/fork.c:171 [inline] dup_task_struct+0x57/0x6d0 kernel/fork.c:980 copy_process+0x637/0x4060 kernel/fork.c:2098 kernel_clone+0x222/0x920 kernel/fork.c:2682 kernel_thread+0x152/0x1d0 kernel/fork.c:2742 create_kthread kernel/kthread.c:399 [inline] kthreadd+0x596/0x760 kernel/kthread.c:746 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:307 page_owner free stack trace missing Memory state around the buggy address: ffff888028e02680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888028e02700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888028e02780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888028e02800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888028e02880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess), 1 bytes skipped: 0: f6 f6 div %dh 2: 48 83 e3 08 and $0x8,%rbx 6: 0f 85 0b 01 00 00 jne 0x117 c: 4c 8d 74 24 20 lea 0x20(%rsp),%r14 11: e8 84 82 fd f6 call 0xf6fd829a 16: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 1b: e8 2a c2 f6 f6 call 0xf6f6c24a 20: 0f 00 2d 33 7b b3 00 verw 0xb37b33(%rip) # 0xb37b5a 27: fb sti 28: f4 hlt * 29: 4c 89 f3 mov %r14,%rbx <-- trapping instruction 2c: 48 c1 eb 03 shr $0x3,%rbx 30: 42 80 3c 3b 00 cmpb $0x0,(%rbx,%r15,1) 35: 74 08 je 0x3f 37: 4c 89 f7 mov %r14,%rdi 3a: e8 ab 37 4e f7 call 0xf74e37ea