================================================================== BUG: KASAN: use-after-free in __lock_acquire+0x114/0x7638 kernel/locking/lockdep.c:4882 Read of size 8 at addr ffff0000c23a2458 by task syz-executor.0/5095 CPU: 0 PID: 5095 Comm: syz-executor.0 Not tainted 5.15.157-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 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:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x554/0x718 kernel/time/timer.c:1767 run_timer_softirq+0x7c/0x114 kernel/time/timer.c:1780 __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] shmem_getpage_gfp+0x19d4/0x20e4 mm/shmem.c:1951 shmem_getpage mm/shmem.c:151 [inline] shmem_write_begin+0xe0/0x29c mm/shmem.c:2477 generic_perform_write+0x24c/0x520 mm/filemap.c:3785 __generic_file_write_iter+0x230/0x454 mm/filemap.c:3912 generic_file_write_iter+0xb4/0x1b8 mm/filemap.c:3944 call_write_iter include/linux/fs.h:2172 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x87c/0xb3c fs/read_write.c:594 ksys_write+0x15c/0x26c fs/read_write.c:647 __do_sys_write fs/read_write.c:659 [inline] __se_sys_write fs/read_write.c:656 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:656 __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 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:357 [inline] kthreadd+0x588/0x7d0 kernel/kthread.c:701 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 Freed by task 4974: 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_irq+0x90/0x274 kernel/sched/core.c:6780 arm64_preempt_schedule_irq+0x174/0x2c4 arch/arm64/kernel/entry-common.c:260 el1_interrupt+0x40/0x58 arch/arm64/kernel/entry-common.c:463 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:470 el1h_64_irq+0x78/0x7c arch/arm64/kernel/entry.S:580 check_kcov_mode kernel/kcov.c:163 [inline] write_comp_data kernel/kcov.c:218 [inline] __sanitizer_cov_trace_const_cmp8+0x5c/0xa8 kernel/kcov.c:291 walk_stackframe arch/arm64/kernel/stacktrace.c:148 [inline] arch_stack_walk+0x270/0x32c arch/arm64/kernel/stacktrace.c:238 stack_trace_save+0xfc/0x1a0 kernel/stacktrace.c:122 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] slab_alloc mm/slub.c:3228 [inline] kmem_cache_alloc+0x1dc/0x45c mm/slub.c:3233 ext4_alloc_inode+0x28/0x464 fs/ext4/super.c:1296 alloc_inode fs/inode.c:236 [inline] new_inode_pseudo+0x68/0x200 fs/inode.c:937 new_inode+0x38/0x174 fs/inode.c:966 __ext4_new_inode+0x2d0/0x39a8 fs/ext4/ialloc.c:960 ext4_create+0x234/0x480 fs/ext4/namei.c:2834 lookup_open fs/namei.c:3462 [inline] open_last_lookups fs/namei.c:3532 [inline] path_openat+0xf18/0x26cc fs/namei.c:3739 do_filp_open+0x1a8/0x3b4 fs/namei.c:3769 do_sys_openat2+0x128/0x3d8 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __arm64_sys_openat+0x1f0/0x240 fs/open.c:1280 __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 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 ffff0000c23a1b40 which belongs to the cache task_struct of size 6720 The buggy address is located 2328 bytes inside of 6720-byte region [ffff0000c23a1b40, ffff0000c23a3580) The buggy address belongs to the page: page:00000000789e64e5 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1023a0 head:00000000789e64e5 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff0000c80a7001 flags: 0x5ffe00000010200(slab|head|node=0|zone=2|lastcpupid=0xfff) raw: 05ffe00000010200 dead000000000100 dead000000000122 ffff0000c0840d80 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff0000c80a7001 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000c23a2300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000c23a2380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000c23a2400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000c23a2480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000c23a2500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================