[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.105' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 71.300692][ T9090] ================================================================== [ 71.309061][ T9090] BUG: KASAN: use-after-free in __lock_acquire+0x3e6f/0x54c0 [ 71.316474][ T9090] Read of size 8 at addr ffff8880151ac0d0 by task syz-executor363/9090 [ 71.325026][ T9090] [ 71.328010][ T9090] CPU: 1 PID: 9090 Comm: syz-executor363 Not tainted 5.11.0-next-20210224-syzkaller #0 [ 71.337750][ T9090] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 71.348084][ T9090] Call Trace: [ 71.351551][ T9090] dump_stack+0xfa/0x151 [ 71.356106][ T9090] ? __lock_acquire+0x3e6f/0x54c0 [ 71.361381][ T9090] print_address_description.constprop.0.cold+0x5b/0x2f8 [ 71.368516][ T9090] ? __lock_acquire+0x3e6f/0x54c0 [ 71.373637][ T9090] ? __lock_acquire+0x3e6f/0x54c0 [ 71.378669][ T9090] kasan_report.cold+0x7c/0xd8 [ 71.383623][ T9090] ? __lock_acquire+0x3e6f/0x54c0 [ 71.388766][ T9090] __lock_acquire+0x3e6f/0x54c0 [ 71.393946][ T9090] ? lock_acquire+0x1bb/0x730 executing program [ 71.398734][ T9090] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 71.404911][ T9090] lock_acquire+0x1ab/0x730 [ 71.409429][ T9090] ? try_to_wake_up+0x98/0x14a0 [ 71.414469][ T9090] ? lock_release+0x710/0x710 [ 71.419341][ T9090] ? lock_downgrade+0x6d0/0x6d0 [ 71.424317][ T9090] ? __cpuhp_state_remove_instance+0x15e/0x5b0 [ 71.430942][ T9090] ? lock_is_held_type+0xd5/0x130 [ 71.436319][ T9090] ? _raw_spin_lock_irqsave+0x4e/0x50 [ 71.441727][ T9090] _raw_spin_lock_irqsave+0x39/0x50 executing program executing program [ 71.447476][ T9090] ? try_to_wake_up+0x98/0x14a0 [ 71.452575][ T9090] try_to_wake_up+0x98/0x14a0 [ 71.457691][ T9090] ? migrate_swap_stop+0x9f0/0x9f0 [ 71.463227][ T9090] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 71.470003][ T9090] ? __cpuhp_state_remove_instance+0x3de/0x5b0 [ 71.476294][ T9090] io_wq_destroy+0x74/0x3d0 [ 71.480997][ T9090] __io_uring_files_cancel+0x195/0x230 [ 71.486689][ T9090] ? __io_uring_free+0xc0/0xc0 [ 71.491713][ T9090] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 executing program executing program [ 71.498206][ T9090] ? __validate_process_creds+0x20c/0x370 [ 71.504299][ T9090] do_exit+0x299/0x2a60 [ 71.509798][ T9090] ? find_held_lock+0x2d/0x110 [ 71.514937][ T9090] ? lock_release+0x3bb/0x710 [ 71.519738][ T9090] ? mm_update_next_owner+0x7a0/0x7a0 [ 71.525295][ T9090] ? lock_downgrade+0x6d0/0x6d0 [ 71.530265][ T9090] ? _raw_spin_unlock_irq+0x1f/0x40 [ 71.535695][ T9090] do_group_exit+0x125/0x310 [ 71.540573][ T9090] __x64_sys_exit_group+0x3a/0x50 [ 71.545625][ T9090] do_syscall_64+0x2d/0x70 executing program [ 71.550353][ T9090] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 71.556772][ T9090] RIP: 0033:0x43e939 [ 71.561551][ T9090] Code: 00 49 c7 c0 c0 ff ff ff be e7 00 00 00 ba 3c 00 00 00 eb 12 0f 1f 44 00 00 89 d0 0f 05 48 3d 00 f0 ff ff 77 1c f4 89 f0 0f 05 <48> 3d 00 f0 ff ff 76 e7 f7 d8 64 41 89 00 eb df 0f 1f 80 00 00 00 [ 71.581534][ T9090] RSP: 002b:00007fff59022f28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 71.590253][ T9090] RAX: ffffffffffffffda RBX: 00000000004b02f0 RCX: 000000000043e939 executing program [ 71.598246][ T9090] RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 [ 71.606401][ T9090] RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 0000000000000001 [ 71.614525][ T9090] R10: 00007fff590229f0 R11: 0000000000000246 R12: 00000000004b02f0 [ 71.622598][ T9090] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 [ 71.630892][ T9090] [ 71.633339][ T9090] Allocated by task 9090: [ 71.637935][ T9090] kasan_save_stack+0x1b/0x40 [ 71.642998][ T9090] __kasan_slab_alloc+0x75/0x90 [ 71.647869][ T9090] kmem_cache_alloc_node+0x16d/0x3c0 [ 71.653178][ T9090] copy_process+0x613/0x6fd0 [ 71.657881][ T9090] kernel_clone+0xe7/0xab0 [ 71.662401][ T9090] io_wq_fork_thread+0xa7/0xe0 [ 71.667209][ T9090] io_wq_create+0x81c/0xab0 [ 71.671899][ T9090] io_uring_alloc_task_context+0x185/0x510 [ 71.678224][ T9090] io_uring_add_task_file+0x261/0x350 [ 71.683818][ T9090] io_uring_setup+0x14c7/0x2c20 [ 71.688872][ T9090] do_syscall_64+0x2d/0x70 [ 71.693307][ T9090] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 71.699694][ T9090] [ 71.702026][ T9090] Freed by task 8450: [ 71.706112][ T9090] kasan_save_stack+0x1b/0x40 [ 71.711199][ T9090] kasan_set_track+0x1c/0x30 [ 71.715809][ T9090] kasan_set_free_info+0x20/0x30 [ 71.721034][ T9090] __kasan_slab_free+0xf5/0x130 [ 71.726080][ T9090] slab_free_freelist_hook+0x72/0x1b0 [ 71.731831][ T9090] kmem_cache_free+0x8b/0x730 [ 71.737051][ T9090] __put_task_struct+0x267/0x3f0 [ 71.742188][ T9090] delayed_put_task_struct+0x1f6/0x340 [ 71.748757][ T9090] rcu_core+0x722/0x1280 [ 71.753335][ T9090] __do_softirq+0x29b/0x9f6 [ 71.758154][ T9090] [ 71.760496][ T9090] Last potentially related work creation: [ 71.766296][ T9090] kasan_save_stack+0x1b/0x40 [ 71.771278][ T9090] kasan_record_aux_stack+0xe5/0x110 [ 71.776685][ T9090] call_rcu+0xb1/0x700 [ 71.781034][ T9090] put_task_struct_rcu_user+0x7f/0xb0 [ 71.786646][ T9090] __schedule+0x914/0x21a0 [ 71.791099][ T9090] preempt_schedule_irq+0x4e/0x90 [ 71.799370][ T9090] irqentry_exit+0x7a/0xa0 [ 71.803946][ T9090] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 71.810834][ T9090] [ 71.813408][ T9090] The buggy address belongs to the object at ffff8880151ab800 [ 71.813408][ T9090] which belongs to the cache task_struct of size 6912 [ 71.830624][ T9090] The buggy address is located 2256 bytes inside of [ 71.830624][ T9090] 6912-byte region [ffff8880151ab800, ffff8880151ad300) [ 71.845414][ T9090] The buggy address belongs to the page: [ 71.851339][ T9090] page:00000000c8e4db1e refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x151a8 [ 71.861693][ T9090] head:00000000c8e4db1e order:3 compound_mapcount:0 compound_pincount:0 [ 71.870580][ T9090] flags: 0xfff00000010200(slab|head) [ 71.876012][ T9090] raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888140004000 [ 71.884961][ T9090] raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000 [ 71.894459][ T9090] page dumped because: kasan: bad access detected [ 71.901067][ T9090] [ 71.903516][ T9090] Memory state around the buggy address: [ 71.909249][ T9090] ffff8880151abf80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.917492][ T9090] ffff8880151ac000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.926294][ T9090] >ffff8880151ac080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.934932][ T9090] ^ [ 71.942519][ T9090] ffff8880151ac100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.950765][ T9090] ffff8880151ac180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 71.959029][ T9090] ================================================================== [ 71.967264][ T9090] Disabling lock debugging due to kernel taint [ 71.973509][ T9090] Kernel panic - not syncing: panic_on_warn set ... [ 71.980267][ T9090] CPU: 1 PID: 9090 Comm: syz-executor363 Tainted: G B 5.11.0-next-20210224-syzkaller #0 [ 71.991872][ T9090] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 72.002022][ T9090] Call Trace: [ 72.005486][ T9090] dump_stack+0xfa/0x151 [ 72.010099][ T9090] panic+0x306/0x73d [ 72.014180][ T9090] ? __warn_printk+0xf3/0xf3 [ 72.018956][ T9090] ? __lock_acquire+0x3e6f/0x54c0 [ 72.025150][ T9090] ? __lock_acquire+0x3e6f/0x54c0 [ 72.030374][ T9090] ? __lock_acquire+0x3e6f/0x54c0 [ 72.035410][ T9090] end_report.cold+0x5a/0x5a [ 72.040016][ T9090] kasan_report.cold+0x6a/0xd8 [ 72.044791][ T9090] ? __lock_acquire+0x3e6f/0x54c0 [ 72.050225][ T9090] __lock_acquire+0x3e6f/0x54c0 [ 72.055287][ T9090] ? lock_acquire+0x1bb/0x730 [ 72.060169][ T9090] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 72.066362][ T9090] lock_acquire+0x1ab/0x730 [ 72.071049][ T9090] ? try_to_wake_up+0x98/0x14a0 [ 72.076087][ T9090] ? lock_release+0x710/0x710 [ 72.080860][ T9090] ? lock_downgrade+0x6d0/0x6d0 [ 72.086159][ T9090] ? __cpuhp_state_remove_instance+0x15e/0x5b0 [ 72.092600][ T9090] ? lock_is_held_type+0xd5/0x130 [ 72.097728][ T9090] ? _raw_spin_lock_irqsave+0x4e/0x50 [ 72.103315][ T9090] _raw_spin_lock_irqsave+0x39/0x50 [ 72.108535][ T9090] ? try_to_wake_up+0x98/0x14a0 [ 72.113704][ T9090] try_to_wake_up+0x98/0x14a0 [ 72.119358][ T9090] ? migrate_swap_stop+0x9f0/0x9f0 [ 72.124506][ T9090] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 72.130768][ T9090] ? __cpuhp_state_remove_instance+0x3de/0x5b0 [ 72.137060][ T9090] io_wq_destroy+0x74/0x3d0 [ 72.141886][ T9090] __io_uring_files_cancel+0x195/0x230 [ 72.147561][ T9090] ? __io_uring_free+0xc0/0xc0 [ 72.152347][ T9090] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 72.158773][ T9090] ? __validate_process_creds+0x20c/0x370 [ 72.164505][ T9090] do_exit+0x299/0x2a60 [ 72.168903][ T9090] ? find_held_lock+0x2d/0x110 [ 72.173771][ T9090] ? lock_release+0x3bb/0x710 [ 72.178461][ T9090] ? mm_update_next_owner+0x7a0/0x7a0 [ 72.184020][ T9090] ? lock_downgrade+0x6d0/0x6d0 [ 72.188905][ T9090] ? _raw_spin_unlock_irq+0x1f/0x40 [ 72.194211][ T9090] do_group_exit+0x125/0x310 [ 72.198817][ T9090] __x64_sys_exit_group+0x3a/0x50 [ 72.203859][ T9090] do_syscall_64+0x2d/0x70 [ 72.209982][ T9090] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 72.216778][ T9090] RIP: 0033:0x43e939 [ 72.220983][ T9090] Code: 00 49 c7 c0 c0 ff ff ff be e7 00 00 00 ba 3c 00 00 00 eb 12 0f 1f 44 00 00 89 d0 0f 05 48 3d 00 f0 ff ff 77 1c f4 89 f0 0f 05 <48> 3d 00 f0 ff ff 76 e7 f7 d8 64 41 89 00 eb df 0f 1f 80 00 00 00 [ 72.240974][ T9090] RSP: 002b:00007fff59022f28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 72.250064][ T9090] RAX: ffffffffffffffda RBX: 00000000004b02f0 RCX: 000000000043e939 [ 72.258138][ T9090] RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 [ 72.266452][ T9090] RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 0000000000000001 [ 72.274744][ T9090] R10: 00007fff590229f0 R11: 0000000000000246 R12: 00000000004b02f0 [ 72.282911][ T9090] R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 [ 72.292927][ T9090] Kernel Offset: disabled [ 72.298094][ T9090] Rebooting in 86400 seconds..