================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x74/0x1ff0 kernel/locking/lockdep.c:4882 Read of size 8 at addr ffff888021f0a7e8 by task swapper/1/0 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.15.157-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 print_address_description+0x63/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x16b/0x1c0 mm/kasan/report.c:451 __lock_acquire+0x74/0x1ff0 kernel/locking/lockdep.c:4882 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __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+0xae/0x1300 kernel/sched/core.c:4030 call_timer_fn+0x16d/0x560 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x67c/0x890 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 __do_softirq+0x3b3/0x93a kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 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:132 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:110 [inline] RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:570 Code: 1d 59 f7 48 83 e3 08 0f 85 0a 01 00 00 4c 8d 74 24 20 e8 44 99 5f f7 0f 1f 44 00 00 e8 3a 19 59 f7 0f 00 2d b3 d8 bb 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 ab f1 a2 f7 RSP: 0018:ffffc90000d67b00 EFLAGS: 000002d3 RAX: ffffffff8a2743a6 RBX: 0000000000000000 RCX: ffff8880129c8000 RDX: 0000000000000000 RSI: ffffffff8a8b2980 RDI: ffffffff8ad8f500 RBP: ffffc90000d67b90 R08: ffffffff8186dd10 R09: ffffed1002539001 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920001acf60 R13: ffff888018fba004 R14: ffffc90000d67b20 R15: dffffc0000000000 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:705 cpuidle_enter_state+0x521/0xef0 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:351 call_cpuidle kernel/sched/idle.c:158 [inline] cpuidle_idle_call kernel/sched/idle.c:239 [inline] do_idle+0x3e4/0x670 kernel/sched/idle.c:306 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_secondary+0x371/0x500 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xb1/0xbb Allocated by task 2: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] __kasan_slab_alloc+0x8e/0xc0 mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x53/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3220 [inline] kmem_cache_alloc_node+0x121/0x2c0 mm/slub.c:3256 alloc_task_struct_node kernel/fork.c:171 [inline] dup_task_struct+0x57/0xb60 kernel/fork.c:894 copy_process+0x5eb/0x3ef0 kernel/fork.c:2038 kernel_clone+0x210/0x960 kernel/fork.c:2604 kernel_thread+0x168/0x1e0 kernel/fork.c:2656 create_kthread kernel/kthread.c:357 [inline] kthreadd+0x57a/0x740 kernel/kthread.c:701 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300 Freed by task 3632: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kmem_cache_free+0x91/0x1f0 mm/slub.c:3515 rcu_do_batch kernel/rcu/tree.c:2523 [inline] rcu_core+0xa15/0x1650 kernel/rcu/tree.c:2763 __do_softirq+0x3b3/0x93a kernel/softirq.c:558 Last potentially related work creation: kasan_save_stack+0x36/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3007 [inline] call_rcu+0x1c4/0xa70 kernel/rcu/tree.c:3087 context_switch kernel/sched/core.c:5033 [inline] __schedule+0x12cc/0x45b0 kernel/sched/core.c:6376 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6552 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6577 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] _raw_spin_unlock_irqrestore+0x128/0x130 kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline] __wake_up_common_lock kernel/sched/wait.c:140 [inline] __wake_up+0x120/0x1c0 kernel/sched/wait.c:157 fsnotify_insert_event+0x345/0x410 fs/notify/notification.c:127 fsnotify_add_event include/linux/fsnotify_backend.h:627 [inline] inotify_handle_inode_event+0x3b2/0x530 fs/notify/inotify/inotify_fsnotify.c:126 inotify_ignored_and_remove_idr+0x25/0x70 fs/notify/inotify/inotify_user.c:519 __do_sys_inotify_rm_watch fs/notify/inotify/inotify_user.c:809 [inline] __se_sys_inotify_rm_watch+0x164/0x230 fs/notify/inotify/inotify_user.c:786 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Second to last potentially related work creation: kasan_save_stack+0x36/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3007 [inline] call_rcu+0x1c4/0xa70 kernel/rcu/tree.c:3087 context_switch kernel/sched/core.c:5033 [inline] __schedule+0x12cc/0x45b0 kernel/sched/core.c:6376 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643 The buggy address belongs to the object at ffff888021f09dc0 which belongs to the cache task_struct of size 7360 The buggy address is located 2600 bytes inside of 7360-byte region [ffff888021f09dc0, ffff888021f0ba80) The buggy address belongs to the page: page:ffffea000087c200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x21f08 head:ffffea000087c200 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff8880231f4001 flags: 0xfff80000010200(slab|head|node=0|zone=1|lastcpupid=0xfff) raw: 00fff80000010200 0000000000000000 0000000100000001 ffff888011deb3c0 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff8880231f4001 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, ts 8239164468, free_ts 0 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159 __alloc_pages+0x272/0x700 mm/page_alloc.c:5423 alloc_slab_page mm/slub.c:1775 [inline] allocate_slab mm/slub.c:1912 [inline] new_slab+0xbb/0x4b0 mm/slub.c:1975 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008 __slab_alloc mm/slub.c:3095 [inline] slab_alloc_node mm/slub.c:3186 [inline] kmem_cache_alloc_node+0x1ba/0x2c0 mm/slub.c:3256 alloc_task_struct_node kernel/fork.c:171 [inline] dup_task_struct+0x57/0xb60 kernel/fork.c:894 copy_process+0x5eb/0x3ef0 kernel/fork.c:2038 kernel_clone+0x210/0x960 kernel/fork.c:2604 kernel_thread+0x168/0x1e0 kernel/fork.c:2656 create_kthread kernel/kthread.c:357 [inline] kthreadd+0x57a/0x740 kernel/kthread.c:701 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300 page_owner free stack trace missing Memory state around the buggy address: ffff888021f0a680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888021f0a700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888021f0a780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888021f0a800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888021f0a880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 1d 59 f7 48 83 sbb $0x8348f759,%eax 5: e3 08 jrcxz 0xf 7: 0f 85 0a 01 00 00 jne 0x117 d: 4c 8d 74 24 20 lea 0x20(%rsp),%r14 12: e8 44 99 5f f7 call 0xf75f995b 17: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 1c: e8 3a 19 59 f7 call 0xf759195b 21: 0f 00 2d b3 d8 bb 00 verw 0xbbd8b3(%rip) # 0xbbd8db 28: fb sti 29: f4 hlt * 2a: 4c 89 f3 mov %r14,%rbx <-- trapping instruction 2d: 48 c1 eb 03 shr $0x3,%rbx 31: 42 80 3c 3b 00 cmpb $0x0,(%rbx,%r15,1) 36: 74 08 je 0x40 38: 4c 89 f7 mov %r14,%rdi 3b: e8 ab f1 a2 f7 call 0xf7a2f1eb