================================================================== BUG: KASAN: use-after-free in debug_spin_lock_before kernel/locking/spinlock_debug.c:85 [inline] BUG: KASAN: use-after-free in do_raw_spin_lock+0x261/0x2a0 kernel/locking/spinlock_debug.c:114 Read of size 4 at addr ffff888025a026b4 by task swapper/1/0 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.1.0-rc2-syzkaller-00105-gb229b6ca5abb #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x15e/0x45d mm/kasan/report.c:395 kasan_report+0xbb/0x1f0 mm/kasan/report.c:495 debug_spin_lock_before kernel/locking/spinlock_debug.c:85 [inline] do_raw_spin_lock+0x261/0x2a0 kernel/locking/spinlock_debug.c:114 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0x41/0x50 kernel/locking/spinlock.c:162 try_to_wake_up+0xb2/0x20f0 kernel/sched/core.c:4076 call_timer_fn+0x1da/0x7c0 kernel/time/timer.c:1474 expire_timers kernel/time/timer.c:1519 [inline] __run_timers.part.0+0x6a2/0xaf0 kernel/time/timer.c:1790 __run_timers kernel/time/timer.c:1768 [inline] run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803 __do_softirq+0x1f7/0xad8 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650 irq_exit_rcu+0x5/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:29 [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+0x1fd/0x2a0 drivers/acpi/processor_idle.c:572 Code: 89 de e8 06 f9 ea f7 84 db 75 ac e8 6d fc ea f7 e8 28 73 f1 f7 eb 0c e8 61 fc ea f7 0f 00 2d da fd c2 00 e8 55 fc ea f7 fb f4 <9c> 5b 81 e3 00 02 00 00 fa 31 ff 48 89 de e8 30 f9 ea f7 48 85 db RSP: 0018:ffffc90000177d10 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: ffff888011a81d40 RSI: ffffffff8991a02b RDI: ffffffff8991a018 RBP: ffff8881458a3864 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 R13: ffff8881458a3800 R14: ffff8881458a3864 R15: ffff88801ba71004 acpi_idle_enter+0x364/0x500 drivers/acpi/processor_idle.c:709 cpuidle_enter_state+0x1ab/0xd30 drivers/cpuidle/cpuidle.c:239 cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:356 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x3f7/0x590 kernel/sched/idle.c:303 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:400 start_secondary+0x252/0x300 arch/x86/kernel/smpboot.c:262 secondary_startup_64_no_verify+0xce/0xdb Allocated by task 2: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 kasan_set_track+0x21/0x30 mm/kasan/common.c:52 __kasan_slab_alloc+0x7e/0x80 mm/kasan/common.c:325 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slab.h:737 [inline] slab_alloc_node mm/slub.c:3398 [inline] kmem_cache_alloc_node+0x2fc/0x400 mm/slub.c:3443 alloc_task_struct_node kernel/fork.c:171 [inline] dup_task_struct kernel/fork.c:966 [inline] copy_process+0x5c2/0x7190 kernel/fork.c:2084 kernel_clone+0xe7/0x980 kernel/fork.c:2671 kernel_thread+0xb5/0xf0 kernel/fork.c:2731 create_kthread kernel/kthread.c:399 [inline] kthreadd+0x4ea/0x750 kernel/kthread.c:746 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 Freed by task 15: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 kasan_set_track+0x21/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2a/0x40 mm/kasan/generic.c:511 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] kmem_cache_free+0xea/0x5b0 mm/slub.c:3683 put_task_struct include/linux/sched/task.h:119 [inline] delayed_put_task_struct+0x26a/0x3d0 kernel/exit.c:178 rcu_do_batch kernel/rcu/tree.c:2250 [inline] rcu_core+0x81f/0x1980 kernel/rcu/tree.c:2510 __do_softirq+0x1f7/0xad8 kernel/softirq.c:571 Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:481 call_rcu+0x99/0x820 kernel/rcu/tree.c:2798 put_task_struct_rcu_user+0x7f/0xc0 kernel/exit.c:184 context_switch kernel/sched/core.c:5194 [inline] __schedule+0xaf1/0x53f0 kernel/sched/core.c:6503 schedule+0xda/0x1b0 kernel/sched/core.c:6579 schedule_hrtimeout_range_clock+0x195/0x390 kernel/time/hrtimer.c:2305 ep_poll fs/eventpoll.c:1878 [inline] do_epoll_wait+0x12ba/0x1950 fs/eventpoll.c:2256 __do_sys_epoll_wait fs/eventpoll.c:2268 [inline] __se_sys_epoll_wait fs/eventpoll.c:2263 [inline] __x64_sys_epoll_wait+0x158/0x270 fs/eventpoll.c:2263 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Second to last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:45 __kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:481 call_rcu+0x99/0x820 kernel/rcu/tree.c:2798 put_task_struct_rcu_user+0x7f/0xc0 kernel/exit.c:184 context_switch kernel/sched/core.c:5194 [inline] __schedule+0xaf1/0x53f0 kernel/sched/core.c:6503 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6672 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 vprintk_emit+0x1ea/0x5f0 kernel/printk/printk.c:2269 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50 _printk+0xba/0xed kernel/printk/printk.c:2289 __nilfs_msg+0x1f7/0x25c fs/nilfs2/super.c:78 nilfs_segctor_thread+0x216/0xf30 fs/nilfs2/segment.c:2550 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 The buggy address belongs to the object at ffff888025a01d40 which belongs to the cache task_struct of size 7232 The buggy address is located 2420 bytes inside of 7232-byte region [ffff888025a01d40, ffff888025a03980) The buggy address belongs to the physical page: page:ffffea0000968000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25a00 head:ffffea0000968000 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0000820e00 dead000000000002 ffff8880119d53c0 raw: 0000000000000000 0000000080040004 00000001ffffffff 0000000000000000 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 51, tgid 51 (kworker/u4:3), ts 8817484297, free_ts 0 prep_new_page mm/page_alloc.c:2538 [inline] get_page_from_freelist+0x10b5/0x2d50 mm/page_alloc.c:4287 __alloc_pages+0x1c7/0x5a0 mm/page_alloc.c:5554 alloc_pages+0x1a6/0x270 mm/mempolicy.c:2285 alloc_slab_page mm/slub.c:1794 [inline] allocate_slab+0x213/0x300 mm/slub.c:1939 new_slab mm/slub.c:1992 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3180 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3279 slab_alloc_node mm/slub.c:3364 [inline] kmem_cache_alloc_node+0x189/0x400 mm/slub.c:3443 alloc_task_struct_node kernel/fork.c:171 [inline] dup_task_struct kernel/fork.c:966 [inline] copy_process+0x5c2/0x7190 kernel/fork.c:2084 kernel_clone+0xe7/0x980 kernel/fork.c:2671 user_mode_thread+0xad/0xe0 kernel/fork.c:2747 call_usermodehelper_exec_work kernel/umh.c:175 [inline] call_usermodehelper_exec_work+0xcc/0x180 kernel/umh.c:161 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 page_owner free stack trace missing Memory state around the buggy address: ffff888025a02580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888025a02600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888025a02680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888025a02700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888025a02780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 89 de mov %ebx,%esi 2: e8 06 f9 ea f7 callq 0xf7eaf90d 7: 84 db test %bl,%bl 9: 75 ac jne 0xffffffb7 b: e8 6d fc ea f7 callq 0xf7eafc7d 10: e8 28 73 f1 f7 callq 0xf7f1733d 15: eb 0c jmp 0x23 17: e8 61 fc ea f7 callq 0xf7eafc7d 1c: 0f 00 2d da fd c2 00 verw 0xc2fdda(%rip) # 0xc2fdfd 23: e8 55 fc ea f7 callq 0xf7eafc7d 28: fb sti 29: f4 hlt * 2a: 9c pushfq <-- trapping instruction 2b: 5b pop %rbx 2c: 81 e3 00 02 00 00 and $0x200,%ebx 32: fa cli 33: 31 ff xor %edi,%edi 35: 48 89 de mov %rbx,%rsi 38: e8 30 f9 ea f7 callq 0xf7eaf96d 3d: 48 85 db test %rbx,%rbx