Starting Permit User Sessions... [ OK ] Started Daily Cleanup of Temporary Directories. [ OK ] Reached target Timers. Starting System Logging Service... [ OK ] Started Regular background program processing daemon. Starting getty on tty2-tty6 if dbus and logind are not available... [ OK ] Started Permit User Sessions. [ OK ] Started System Logging Service. [ OK ] Started OpenBSD Secure Shell server. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. [ OK ] Listening on Load/Save RF Kill Switch Status /dev/rfkill Watch. [ OK ] Started Getty on tty6. [ OK ] Started Getty on tty5. [ 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... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.54' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 58.941755][ T6806] input: syz1 as /devices/virtual/input/input5 [ 58.955263][ T6806] ================================================================== [ 58.963501][ T6806] BUG: KASAN: use-after-free in __mutex_lock+0x1033/0x13c0 [ 58.970705][ T6806] Read of size 8 at addr ffff88809f3ff158 by task syz-executor172/6806 [ 58.978976][ T6806] [ 58.981411][ T6806] CPU: 0 PID: 6806 Comm: syz-executor172 Not tainted 5.7.0-rc6-next-20200522-syzkaller #0 [ 58.991294][ T6806] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.001363][ T6806] Call Trace: [ 59.004682][ T6806] dump_stack+0x18f/0x20d [ 59.009001][ T6806] ? __mutex_lock+0x1033/0x13c0 [ 59.013830][ T6806] ? __mutex_lock+0x1033/0x13c0 [ 59.018764][ T6806] print_address_description.constprop.0.cold+0xd3/0x413 [ 59.025896][ T6806] ? cdev_device_del+0x69/0x80 [ 59.030642][ T6806] ? evdev_disconnect+0x3d/0xb0 [ 59.035568][ T6806] ? __input_unregister_device+0x1b0/0x430 [ 59.041533][ T6806] ? input_unregister_device+0xb4/0xf0 [ 59.046965][ T6806] ? uinput_destroy_device+0x1e2/0x240 [ 59.052419][ T6806] ? vprintk_func+0x97/0x1a6 [ 59.056987][ T6806] ? __mutex_lock+0x1033/0x13c0 [ 59.061826][ T6806] kasan_report.cold+0x1f/0x37 [ 59.066569][ T6806] ? __mutex_lock+0x1033/0x13c0 [ 59.071409][ T6806] __mutex_lock+0x1033/0x13c0 [ 59.076066][ T6806] ? evdev_cleanup+0x21/0x190 [ 59.080720][ T6806] ? print_usage_bug+0x240/0x240 [ 59.085721][ T6806] ? trace_hardirqs_off+0x50/0x220 [ 59.090814][ T6806] ? mutex_trylock+0x2c0/0x2c0 [ 59.095583][ T6806] ? mark_held_locks+0x9f/0xe0 [ 59.100771][ T6806] ? kfree+0x1eb/0x2b0 [ 59.105111][ T6806] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 59.111186][ T6806] ? kfree_const+0x51/0x60 [ 59.115620][ T6806] ? evdev_cleanup+0x21/0x190 [ 59.120280][ T6806] evdev_cleanup+0x21/0x190 [ 59.124951][ T6806] evdev_disconnect+0x45/0xb0 [ 59.129677][ T6806] __input_unregister_device+0x1b0/0x430 [ 59.135307][ T6806] input_unregister_device+0xb4/0xf0 [ 59.140770][ T6806] uinput_destroy_device+0x1e2/0x240 [ 59.146757][ T6806] ? uinput_destroy_device+0x240/0x240 [ 59.152339][ T6806] uinput_release+0x37/0x50 [ 59.156848][ T6806] __fput+0x33e/0x880 [ 59.160866][ T6806] task_work_run+0xf4/0x1b0 [ 59.165376][ T6806] do_exit+0xb5e/0x2e10 [ 59.169551][ T6806] ? fsnotify_first_mark+0x191/0x200 [ 59.174857][ T6806] ? debug_smp_processor_id+0x2f/0x185 [ 59.180316][ T6806] ? mm_update_next_owner+0x7a0/0x7a0 [ 59.185774][ T6806] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 59.191748][ T6806] ? vfs_write+0x161/0x5d0 [ 59.196327][ T6806] do_group_exit+0x125/0x340 [ 59.200899][ T6806] __x64_sys_exit_group+0x3a/0x50 [ 59.205912][ T6806] do_syscall_64+0xf6/0x7d0 [ 59.210427][ T6806] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 59.216560][ T6806] RIP: 0033:0x43f9e8 [ 59.220632][ T6806] Code: Bad RIP value. [ 59.224689][ T6806] RSP: 002b:00007ffc683264c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 59.233455][ T6806] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043f9e8 [ 59.241660][ T6806] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 59.249619][ T6806] RBP: 00000000004bf228 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 59.257583][ T6806] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 59.265534][ T6806] R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000 [ 59.273971][ T6806] [ 59.276306][ T6806] Allocated by task 6806: [ 59.280841][ T6806] save_stack+0x1b/0x40 [ 59.284988][ T6806] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 59.290805][ T6806] kmem_cache_alloc_trace+0x153/0x7d0 [ 59.296381][ T6806] evdev_connect+0x80/0x4d0 [ 59.301074][ T6806] input_attach_handler+0x194/0x200 [ 59.306990][ T6806] input_register_device.cold+0xf5/0x246 [ 59.312608][ T6806] uinput_ioctl_handler.isra.0+0x1210/0x1d80 [ 59.318587][ T6806] ksys_ioctl+0x11a/0x180 [ 59.322904][ T6806] __x64_sys_ioctl+0x6f/0xb0 [ 59.327472][ T6806] do_syscall_64+0xf6/0x7d0 [ 59.332073][ T6806] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 59.337947][ T6806] [ 59.340262][ T6806] Freed by task 6806: [ 59.344927][ T6806] save_stack+0x1b/0x40 [ 59.349063][ T6806] __kasan_slab_free+0xf7/0x140 [ 59.353887][ T6806] kfree+0x109/0x2b0 [ 59.358837][ T6806] device_release+0x71/0x200 [ 59.363424][ T6806] kobject_put+0x1c8/0x2f0 [ 59.368254][ T6806] cdev_device_del+0x69/0x80 [ 59.372827][ T6806] evdev_disconnect+0x3d/0xb0 [ 59.377496][ T6806] __input_unregister_device+0x1b0/0x430 [ 59.383210][ T6806] input_unregister_device+0xb4/0xf0 [ 59.388770][ T6806] uinput_destroy_device+0x1e2/0x240 [ 59.394503][ T6806] uinput_release+0x37/0x50 [ 59.398985][ T6806] __fput+0x33e/0x880 [ 59.402962][ T6806] task_work_run+0xf4/0x1b0 [ 59.407464][ T6806] do_exit+0xb5e/0x2e10 [ 59.411609][ T6806] do_group_exit+0x125/0x340 [ 59.416188][ T6806] __x64_sys_exit_group+0x3a/0x50 [ 59.421343][ T6806] do_syscall_64+0xf6/0x7d0 [ 59.425846][ T6806] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 59.431839][ T6806] [ 59.434150][ T6806] The buggy address belongs to the object at ffff88809f3ff000 [ 59.434150][ T6806] which belongs to the cache kmalloc-2k of size 2048 [ 59.448190][ T6806] The buggy address is located 344 bytes inside of [ 59.448190][ T6806] 2048-byte region [ffff88809f3ff000, ffff88809f3ff800) [ 59.461537][ T6806] The buggy address belongs to the page: [ 59.467599][ T6806] page:ffffea00027cffc0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 59.476692][ T6806] flags: 0xfffe0000000200(slab) [ 59.481530][ T6806] raw: 00fffe0000000200 ffffea000272bfc8 ffff8880aa001950 ffff8880aa000e00 [ 59.490094][ T6806] raw: 0000000000000000 ffff88809f3ff000 0000000100000001 0000000000000000 [ 59.498654][ T6806] page dumped because: kasan: bad access detected [ 59.505039][ T6806] [ 59.507355][ T6806] Memory state around the buggy address: [ 59.513081][ T6806] ffff88809f3ff000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.521335][ T6806] ffff88809f3ff080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.530140][ T6806] >ffff88809f3ff100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.538410][ T6806] ^ [ 59.545331][ T6806] ffff88809f3ff180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.553566][ T6806] ffff88809f3ff200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.561619][ T6806] ================================================================== [ 59.569730][ T6806] Disabling lock debugging due to kernel taint [ 59.581171][ T6806] Kernel panic - not syncing: panic_on_warn set ... [ 59.587834][ T6806] CPU: 0 PID: 6806 Comm: syz-executor172 Tainted: G B 5.7.0-rc6-next-20200522-syzkaller #0 [ 59.599102][ T6806] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.609422][ T6806] Call Trace: [ 59.612740][ T6806] dump_stack+0x18f/0x20d [ 59.617091][ T6806] ? __mutex_lock+0xf50/0x13c0 [ 59.621862][ T6806] panic+0x2e3/0x75c [ 59.625947][ T6806] ? __warn_printk+0xf3/0xf3 [ 59.630543][ T6806] ? preempt_schedule_common+0x5e/0xc0 [ 59.636024][ T6806] ? __mutex_lock+0x1033/0x13c0 [ 59.640903][ T6806] ? __mutex_lock+0x1033/0x13c0 [ 59.646891][ T6806] ? preempt_schedule_thunk+0x16/0x18 [ 59.652356][ T6806] ? trace_hardirqs_on+0x55/0x230 [ 59.657387][ T6806] ? __mutex_lock+0x1033/0x13c0 [ 59.662717][ T6806] ? __mutex_lock+0x1033/0x13c0 [ 59.667592][ T6806] end_report+0x4d/0x53 [ 59.672035][ T6806] kasan_report.cold+0xd/0x37 [ 59.676696][ T6806] ? __mutex_lock+0x1033/0x13c0 [ 59.681543][ T6806] __mutex_lock+0x1033/0x13c0 [ 59.687447][ T6806] ? evdev_cleanup+0x21/0x190 [ 59.692207][ T6806] ? print_usage_bug+0x240/0x240 [ 59.697247][ T6806] ? trace_hardirqs_off+0x50/0x220 [ 59.702348][ T6806] ? mutex_trylock+0x2c0/0x2c0 [ 59.707192][ T6806] ? mark_held_locks+0x9f/0xe0 [ 59.712227][ T6806] ? kfree+0x1eb/0x2b0 [ 59.717214][ T6806] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 59.723308][ T6806] ? kfree_const+0x51/0x60 [ 59.727995][ T6806] ? evdev_cleanup+0x21/0x190 [ 59.732832][ T6806] evdev_cleanup+0x21/0x190 [ 59.738211][ T6806] evdev_disconnect+0x45/0xb0 [ 59.743050][ T6806] __input_unregister_device+0x1b0/0x430 [ 59.748957][ T6806] input_unregister_device+0xb4/0xf0 [ 59.754495][ T6806] uinput_destroy_device+0x1e2/0x240 [ 59.760078][ T6806] ? uinput_destroy_device+0x240/0x240 [ 59.765531][ T6806] uinput_release+0x37/0x50 [ 59.770014][ T6806] __fput+0x33e/0x880 [ 59.773988][ T6806] task_work_run+0xf4/0x1b0 [ 59.778476][ T6806] do_exit+0xb5e/0x2e10 [ 59.782611][ T6806] ? fsnotify_first_mark+0x191/0x200 [ 59.788342][ T6806] ? debug_smp_processor_id+0x2f/0x185 [ 59.793857][ T6806] ? mm_update_next_owner+0x7a0/0x7a0 [ 59.799222][ T6806] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 59.805351][ T6806] ? vfs_write+0x161/0x5d0 [ 59.809749][ T6806] do_group_exit+0x125/0x340 [ 59.814838][ T6806] __x64_sys_exit_group+0x3a/0x50 [ 59.819866][ T6806] do_syscall_64+0xf6/0x7d0 [ 59.824523][ T6806] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 59.830399][ T6806] RIP: 0033:0x43f9e8 [ 59.834424][ T6806] Code: Bad RIP value. [ 59.838481][ T6806] RSP: 002b:00007ffc683264c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 59.848966][ T6806] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043f9e8 [ 59.857040][ T6806] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 59.865103][ T6806] RBP: 00000000004bf228 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 59.873066][ T6806] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 59.881469][ T6806] R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000 [ 59.891229][ T6806] Kernel Offset: disabled [ 59.895834][ T6806] Rebooting in 86400 seconds..