================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x114/0x7638 kernel/locking/lockdep.c:4882 Read of size 8 at addr ffff0000c6998918 by task syz-executor.2/8171 CPU: 0 PID: 8171 Comm: syz-executor.2 Not tainted 5.15.152-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 print_address_description+0x7c/0x3f0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x174/0x1e4 mm/kasan/report.c:451 __asan_report_load8_noabort+0x44/0x50 mm/kasan/report_generic.c:309 __lock_acquire+0x114/0x7638 kernel/locking/lockdep.c:4882 lock_acquire+0x240/0x77c kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xc4/0x14c kernel/locking/spinlock.c:162 try_to_wake_up+0xb0/0xc2c kernel/sched/core.c:4030 wake_up_process+0x18/0x24 kernel/sched/core.c:4215 nilfs_construction_timeout+0x40/0x50 fs/nilfs2/segment.c:2446 call_timer_fn+0x19c/0x8f0 kernel/time/timer.c:1421 expire_timers kernel/time/timer.c:1466 [inline] __run_timers+0x554/0x718 kernel/time/timer.c:1737 run_timer_softirq+0x7c/0x114 kernel/time/timer.c:1750 __do_softirq+0x344/0xdb0 kernel/softirq.c:558 do_softirq_own_stack include/asm-generic/softirq_stack.h:10 [inline] invoke_softirq kernel/softirq.c:439 [inline] __irq_exit_rcu+0x264/0x4d4 kernel/softirq.c:637 irq_exit+0x14/0x88 kernel/softirq.c:661 handle_domain_irq+0xf4/0x178 kernel/irq/irqdesc.c:710 gic_handle_irq+0x78/0x1c8 drivers/irqchip/irq-gic-v3.c:758 call_on_irq_stack+0x24/0x4c arch/arm64/kernel/entry.S:899 do_interrupt_handler+0x74/0x94 arch/arm64/kernel/entry-common.c:267 el1_interrupt+0x30/0x58 arch/arm64/kernel/entry-common.c:454 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:470 el1h_64_irq+0x78/0x7c arch/arm64/kernel/entry.S:580 arch_local_irq_enable arch/arm64/include/asm/irqflags.h:35 [inline] __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:168 [inline] _raw_spin_unlock_irq+0xa4/0x134 kernel/locking/spinlock.c:202 spin_unlock_irq include/linux/spinlock.h:413 [inline] delete_from_page_cache+0x110/0x17c mm/filemap.c:267 truncate_inode_page+0x98/0xc8 mm/truncate.c:219 shmem_undo_range+0x448/0x1460 mm/shmem.c:960 shmem_truncate_range mm/shmem.c:1063 [inline] shmem_evict_inode+0x1c4/0x844 mm/shmem.c:1145 evict+0x260/0x68c fs/inode.c:587 iput_final fs/inode.c:1705 [inline] iput+0x744/0x824 fs/inode.c:1731 dentry_unlink_inode+0x370/0x4b0 fs/dcache.c:376 __dentry_kill+0x324/0x5e4 fs/dcache.c:582 dentry_kill+0xc8/0x250 dput+0x21c/0x458 fs/dcache.c:889 __fput+0x500/0x7f0 fs/file_table.c:288 ____fput+0x20/0x30 fs/file_table.c:308 task_work_run+0x130/0x1e4 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] do_notify_resume+0x262c/0x32b8 arch/arm64/kernel/signal.c:946 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 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+0x8c/0xcc mm/kasan/common.c:467 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x74/0x3f4 mm/slab.h:519 slab_alloc_node mm/slub.c:3220 [inline] kmem_cache_alloc_node+0x208/0x49c mm/slub.c:3256 alloc_task_struct_node kernel/fork.c:171 [inline] dup_task_struct+0x74/0xcf0 kernel/fork.c:894 copy_process+0x52c/0x3750 kernel/fork.c:2038 kernel_clone+0x1d8/0xa58 kernel/fork.c:2604 kernel_thread+0x148/0x1bc kernel/fork.c:2656 create_kthread kernel/kthread.c:342 [inline] kthreadd+0x588/0x7d0 kernel/kthread.c:686 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 Freed by task 14: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x84 mm/kasan/common.c:46 kasan_set_free_info+0x28/0x4c mm/kasan/generic.c:360 ____kasan_slab_free+0x118/0x164 mm/kasan/common.c:366 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0x128/0x1ec mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kmem_cache_free+0xdc/0x3c4 mm/slub.c:3515 free_task_struct kernel/fork.c:176 [inline] free_task+0xe8/0x14c kernel/fork.c:474 __put_task_struct+0x1a8/0x24c kernel/fork.c:763 put_task_struct include/linux/sched/task.h:141 [inline] delayed_put_task_struct+0x124/0x380 kernel/exit.c:220 rcu_do_batch kernel/rcu/tree.c:2523 [inline] rcu_core+0x830/0x1b34 kernel/rcu/tree.c:2763 rcu_core_si+0x10/0x1c kernel/rcu/tree.c:2776 __do_softirq+0x344/0xdb0 kernel/softirq.c:558 Last potentially related work creation: kasan_save_stack+0x38/0x68 mm/kasan/common.c:38 kasan_record_aux_stack+0xd4/0x11c mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3007 [inline] call_rcu+0x118/0xb40 kernel/rcu/tree.c:3087 put_task_struct_rcu_user+0x70/0xe0 kernel/exit.c:226 finish_task_switch+0x3a0/0x6b4 kernel/sched/core.c:4944 context_switch kernel/sched/core.c:5033 [inline] __schedule+0xf14/0x1e48 kernel/sched/core.c:6376 preempt_schedule_common+0x140/0x260 kernel/sched/core.c:6552 preempt_schedule+0x64/0x84 kernel/sched/core.c:6577 __raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] _raw_spin_unlock_irq+0xf0/0x134 kernel/locking/spinlock.c:202 process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283 worker_thread+0x910/0x1034 kernel/workqueue.c:2457 kthread+0x37c/0x45c kernel/kthread.c:319 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 Second to last potentially related work creation: kasan_save_stack+0x38/0x68 mm/kasan/common.c:38 kasan_record_aux_stack+0xd4/0x11c mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3007 [inline] call_rcu+0x118/0xb40 kernel/rcu/tree.c:3087 release_task+0x1648/0x1748 wait_task_zombie kernel/exit.c:1179 [inline] wait_consider_task+0x16d8/0x2978 kernel/exit.c:1406 do_wait_thread kernel/exit.c:1469 [inline] do_wait+0x2f4/0xac8 kernel/exit.c:1586 kernel_wait4+0x24c/0x400 kernel/exit.c:1749 __do_sys_wait4 kernel/exit.c:1777 [inline] __se_sys_wait4 kernel/exit.c:1773 [inline] __arm64_sys_wait4+0x120/0x2d0 kernel/exit.c:1773 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 The buggy address belongs to the object at ffff0000c6998000 which belongs to the cache task_struct of size 6720 The buggy address is located 2328 bytes inside of 6720-byte region [ffff0000c6998000, ffff0000c6999a40) The buggy address belongs to the page: page:000000001a308c26 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x106998 head:000000001a308c26 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff0000da286401 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 0000000000000000 0000000100000001 ffff0000c083ed80 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff0000da286401 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000c6998800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000c6998880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000c6998900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000c6998980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000c6998a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog