================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x77/0x1f80 kernel/locking/lockdep.c:4919 Read of size 8 at addr ffff888025d0e358 by task syz-executor.1/3785 CPU: 0 PID: 3785 Comm: syz-executor.1 Not tainted 6.1.87-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+0x1e3/0x2cb 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:1504 expire_timers kernel/time/timer.c:1549 [inline] __run_timers+0x67c/0x890 kernel/time/timer.c:1820 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1833 __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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd4/0x130 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 f2 3b 4d f7 f6 44 24 21 02 75 4e 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 d7 88 c9 f6 65 8b 05 78 a4 6d 75 85 c0 74 3f 48 c7 04 24 0e 36 RSP: 0018:ffffc900050c7b00 EFLAGS: 00000206 RAX: 947c938e9f5b2700 RBX: 1ffff92000a18f64 RCX: ffffffff816ad11a RDX: dffffc0000000000 RSI: ffffffff8aec01c0 RDI: 0000000000000001 RBP: ffffc900050c7b90 R08: dffffc0000000000 R09: fffffbfff2093459 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff92000a18f60 R14: ffffc900050c7b20 R15: 0000000000000246 evdev_write+0x668/0x7c0 drivers/input/evdev.c:530 vfs_write+0x2d9/0xba0 fs/read_write.c:582 ksys_write+0x19c/0x2c0 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7efc4e07dea9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007efc4ed4f0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007efc4e1abf80 RCX: 00007efc4e07dea9 RDX: 0000000100000008 RSI: 0000000020000000 RDI: 0000000000000006 RBP: 00007efc4e0ca4a4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007efc4e1abf80 R15: 00007ffefd47e7a8 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:308 Freed by task 3678: 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+0xad5/0x1810 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_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x128/0x130 kernel/locking/spinlock.c:194 __debug_check_no_obj_freed lib/debugobjects.c:987 [inline] debug_check_no_obj_freed+0x455/0x4e0 lib/debugobjects.c:1008 free_pages_prepare mm/page_alloc.c:1446 [inline] free_pcp_prepare mm/page_alloc.c:1490 [inline] free_unref_page_prepare+0x319/0x1120 mm/page_alloc.c:3358 free_unref_page_list+0x663/0x900 mm/page_alloc.c:3499 release_pages+0x2836/0x2b40 mm/swap.c:1055 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline] tlb_flush_mmu_free mm/mmu_gather.c:254 [inline] tlb_flush_mmu+0xfc/0x210 mm/mmu_gather.c:261 tlb_finish_mmu+0xce/0x1f0 mm/mmu_gather.c:361 exit_mmap+0x3c3/0x9f0 mm/mmap.c:3239 __mmput+0x115/0x3c0 kernel/fork.c:1199 exit_mm+0x226/0x300 kernel/exit.c:563 do_exit+0x9f6/0x26a0 kernel/exit.c:856 do_group_exit+0x202/0x2b0 kernel/exit.c:1019 __do_sys_exit_group kernel/exit.c:1030 [inline] __se_sys_exit_group kernel/exit.c:1028 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1028 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 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+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888025d0d940 which belongs to the cache task_struct of size 7360 The buggy address is located 2584 bytes inside of 7360-byte region [ffff888025d0d940, ffff888025d0f600) The buggy address belongs to the physical page: page:ffffea0000974200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25d08 head:ffffea0000974200 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff80000010200(slab|head|node=0|zone=1|lastcpupid=0xfff) raw: 00fff80000010200 dead000000000100 dead000000000122 ffff888140008500 raw: 0000000000000000 0000000000040004 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 2, tgid 2 (kthreadd), ts 15480520734, 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:5547 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:308 page_owner free stack trace missing Memory state around the buggy address: ffff888025d0e200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888025d0e280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888025d0e300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888025d0e380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888025d0e400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 9c pushf 1: 8f 44 24 20 pop 0x20(%rsp) 5: 42 80 3c 23 00 cmpb $0x0,(%rbx,%r12,1) a: 74 08 je 0x14 c: 4c 89 f7 mov %r14,%rdi f: e8 f2 3b 4d f7 call 0xf74d3c06 14: f6 44 24 21 02 testb $0x2,0x21(%rsp) 19: 75 4e jne 0x69 1b: 41 f7 c7 00 02 00 00 test $0x200,%r15d 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 d7 88 c9 f6 call 0xf6c98906 <-- trapping instruction 2f: 65 8b 05 78 a4 6d 75 mov %gs:0x756da478(%rip),%eax # 0x756da4ae 36: 85 c0 test %eax,%eax 38: 74 3f je 0x79 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: 04 24 add $0x24,%al 3e: 0e (bad) 3f: 36 ss