================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x77/0x1f80 kernel/locking/lockdep.c:4919 Read of size 8 at addr ffff888029000a18 by task modprobe/4053 CPU: 0 PID: 4053 Comm: modprobe Not tainted 6.1.88-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:native_save_fl arch/x86/include/asm/irqflags.h:35 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:106 [inline] RIP: 0010:lock_is_held_type+0x65/0x180 kernel/locking/lockdep.c:5701 Code: 00 00 65 4c 8b 2d 8b c4 77 75 41 83 bd dc 0a 00 00 00 0f 85 db 00 00 00 41 89 f6 49 89 ff 48 c7 04 24 00 00 00 00 9c 8f 04 24 <4c> 8b 24 24 fa 48 c7 c7 a0 0e ec 8a e8 9a 16 00 00 65 ff 05 d3 cd RSP: 0018:ffffc9000317f178 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff88805d2240c0 RCX: ffff88801fd71dc0 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff8d12ac00 RBP: 00000000ffffffff R08: dffffc0000000000 R09: ffffed100fa68625 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: ffff88801fd71dc0 R14: 00000000ffffffff R15: ffffffff8d12ac00 lock_is_held include/linux/lockdep.h:283 [inline] __might_resched+0xf0/0x780 kernel/sched/core.c:9904 zap_pmd_range mm/memory.c:1576 [inline] zap_pud_range mm/memory.c:1603 [inline] zap_p4d_range mm/memory.c:1624 [inline] unmap_page_range+0x2217/0x2740 mm/memory.c:1645 unmap_vmas+0x48b/0x640 mm/memory.c:1730 unmap_region+0x1fc/0x2f0 mm/mmap.c:2329 do_mas_align_munmap+0xec8/0x15f0 mm/mmap.c:2582 do_mas_munmap+0x246/0x2b0 mm/mmap.c:2640 mmap_region+0x8e6/0x1fa0 mm/mmap.c:2688 do_mmap+0x8c5/0xf60 mm/mmap.c:1425 vm_mmap_pgoff+0x1ca/0x2d0 mm/util.c:520 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: 0033:0x7fb003318b74 Code: 63 08 44 89 e8 5b 41 5c 41 5d c3 41 89 ca 41 f7 c1 ff 0f 00 00 74 0c c7 05 f5 46 01 00 16 00 00 00 eb 17 b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 0c f7 d8 89 05 dc 46 01 00 48 83 c8 ff c3 0f RSP: 002b:00007ffcc422dc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007ffcc422dd18 RCX: 00007fb003318b74 RDX: 0000000000000003 RSI: 0000000000001888 RDI: 00007fb003085000 RBP: 00007ffcc422e040 R08: 00000000ffffffff R09: 0000000000000000 R10: 0000000000000032 R11: 0000000000000246 R12: 00007fb0032fbac0 R13: 00007ffcc422e0c8 R14: 00007fb003086888 R15: 00007fb003085000 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 21: 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 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:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 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 ffff888029000000 which belongs to the cache task_struct of size 7360 The buggy address is located 2584 bytes inside of 7360-byte region [ffff888029000000, ffff888029001cc0) The buggy address belongs to the physical page: page:ffffea0000a40000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x29000 head:ffffea0000a40000 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff888058937141 flags: 0xfff80000010200(slab|head|node=0|zone=1|lastcpupid=0xfff) raw: 00fff80000010200 0000000000000000 dead000000000001 ffff888140008500 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff888058937141 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 16278801825, 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: ffff888029000900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888029000980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888029000a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888029000a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888029000b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 65 4c 8b 2d 8b c4 77 mov %gs:0x7577c48b(%rip),%r13 # 0x7577c495 9: 75 a: 41 83 bd dc 0a 00 00 cmpl $0x0,0xadc(%r13) 11: 00 12: 0f 85 db 00 00 00 jne 0xf3 18: 41 89 f6 mov %esi,%r14d 1b: 49 89 ff mov %rdi,%r15 1e: 48 c7 04 24 00 00 00 movq $0x0,(%rsp) 25: 00 26: 9c pushf 27: 8f 04 24 pop (%rsp) * 2a: 4c 8b 24 24 mov (%rsp),%r12 <-- trapping instruction 2e: fa cli 2f: 48 c7 c7 a0 0e ec 8a mov $0xffffffff8aec0ea0,%rdi 36: e8 9a 16 00 00 call 0x16d5 3b: 65 gs 3c: ff .byte 0xff 3d: 05 .byte 0x5 3e: d3 cd ror %cl,%ebp