Warning: Permanently added '10.128.0.183' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 104.804508][ T9737] ================================================================== [ 104.804581][ T9737] BUG: KASAN: use-after-free in con_shutdown+0x7f/0x90 [ 104.804592][ T9737] Write of size 8 at addr ffff88808eed7108 by task syz-executor807/9737 [ 104.804595][ T9737] [ 104.804608][ T9737] CPU: 0 PID: 9737 Comm: syz-executor807 Not tainted 5.6.0-rc3-next-20200228-syzkaller #0 [ 104.804616][ T9737] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 104.804621][ T9737] Call Trace: [ 104.804639][ T9737] dump_stack+0x188/0x20d [ 104.804653][ T9737] ? con_shutdown+0x7f/0x90 [ 104.804668][ T9737] ? con_shutdown+0x7f/0x90 [ 104.804684][ T9737] print_address_description.constprop.0.cold+0xd3/0x315 [ 104.804696][ T9737] ? con_shutdown+0x7f/0x90 [ 104.804710][ T9737] ? con_shutdown+0x7f/0x90 [ 104.804721][ T9737] __kasan_report.cold+0x1a/0x32 [ 104.804739][ T9737] ? con_shutdown+0x7f/0x90 [ 104.804758][ T9737] kasan_report+0xe/0x20 [ 104.804771][ T9737] con_shutdown+0x7f/0x90 [ 104.804784][ T9737] ? update_region+0x140/0x140 [ 104.804797][ T9737] release_tty+0xca/0x450 [ 104.804814][ T9737] tty_release_struct+0x37/0x50 [ 104.804828][ T9737] tty_release+0xbc7/0xe90 [ 104.804856][ T9737] ? do_tty_hangup+0x30/0x30 [ 104.804868][ T9737] __fput+0x2da/0x850 [ 104.804897][ T9737] task_work_run+0x13f/0x1b0 [ 104.804918][ T9737] do_exit+0xb53/0x2e10 [ 104.804946][ T9737] ? mm_update_next_owner+0x7a0/0x7a0 [ 104.804960][ T9737] ? up_read+0x1a8/0x750 [ 104.804979][ T9737] ? down_read_nested+0x430/0x430 [ 104.804998][ T9737] ? handle_mm_fault+0x29e/0x660 [ 104.805018][ T9737] do_group_exit+0x125/0x340 [ 104.805035][ T9737] __x64_sys_exit_group+0x3a/0x50 [ 104.805050][ T9737] do_syscall_64+0xf6/0x790 [ 104.805069][ T9737] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 104.805079][ T9737] RIP: 0033:0x43ff38 [ 104.805092][ T9737] Code: 00 00 be 3c 00 00 00 eb 19 66 0f 1f 84 00 00 00 00 00 48 89 d7 89 f0 0f 05 48 3d 00 f0 ff ff 77 21 f4 48 89 d7 44 89 c0 0f 05 <48> 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 0f 1f 84 00 00 00 [ 104.805099][ T9737] RSP: 002b:00007fff737ee4b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 104.805111][ T9737] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 104.805118][ T9737] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 104.805126][ T9737] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 104.805133][ T9737] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 104.805140][ T9737] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 104.805167][ T9737] [ 104.805174][ T9737] Allocated by task 9737: [ 104.805186][ T9737] save_stack+0x1b/0x40 [ 104.805197][ T9737] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 104.805209][ T9737] kmem_cache_alloc_trace+0x153/0x7d0 [ 104.805218][ T9737] vc_allocate+0x1e2/0x6e0 [ 104.805227][ T9737] con_install+0x4f/0x400 [ 104.805237][ T9737] tty_init_dev+0xf5/0x460 [ 104.805246][ T9737] tty_open+0x47f/0xb30 [ 104.805257][ T9737] chrdev_open+0x219/0x5c0 [ 104.805275][ T9737] do_dentry_open+0x49e/0x1250 [ 104.805287][ T9737] path_openat+0x122a/0x3230 [ 104.805296][ T9737] do_filp_open+0x192/0x260 [ 104.805307][ T9737] do_sys_openat2+0x54c/0x740 [ 104.805318][ T9737] do_sys_open+0xc3/0x140 [ 104.805328][ T9737] do_syscall_64+0xf6/0x790 [ 104.805339][ T9737] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 104.805342][ T9737] [ 104.805348][ T9737] Freed by task 9738: [ 104.805358][ T9737] save_stack+0x1b/0x40 [ 104.805369][ T9737] __kasan_slab_free+0xf7/0x140 [ 104.805385][ T9737] kfree+0x109/0x2b0 [ 104.805395][ T9737] vt_disallocate_all+0x283/0x370 [ 104.805405][ T9737] vt_ioctl+0x79e/0x2450 [ 104.805415][ T9737] tty_ioctl+0xedd/0x1440 [ 104.805424][ T9737] ksys_ioctl+0x11a/0x180 [ 104.805432][ T9737] __x64_sys_ioctl+0x6f/0xb0 [ 104.805442][ T9737] do_syscall_64+0xf6/0x790 [ 104.805453][ T9737] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 104.805456][ T9737] [ 104.805465][ T9737] The buggy address belongs to the object at ffff88808eed7000 [ 104.805465][ T9737] which belongs to the cache kmalloc-2k of size 2048 [ 104.805476][ T9737] The buggy address is located 264 bytes inside of [ 104.805476][ T9737] 2048-byte region [ffff88808eed7000, ffff88808eed7800) [ 104.805480][ T9737] The buggy address belongs to the page: [ 104.805492][ T9737] page:ffffea00023bb5c0 refcount:1 mapcount:0 mapping:00000000ff1b9cc1 index:0x0 [ 104.805501][ T9737] flags: 0xfffe0000000200(slab) [ 104.805518][ T9737] raw: 00fffe0000000200 ffffea00023baf48 ffffea00023b9a88 ffff8880aa000e00 [ 104.805538][ T9737] raw: 0000000000000000 ffff88808eed7000 0000000100000001 0000000000000000 [ 104.805543][ T9737] page dumped because: kasan: bad access detected [ 104.805546][ T9737] [ 104.805550][ T9737] Memory state around the buggy address: [ 104.805560][ T9737] ffff88808eed7000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 104.805568][ T9737] ffff88808eed7080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 104.805577][ T9737] >ffff88808eed7100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 104.805581][ T9737] ^ [ 104.805591][ T9737] ffff88808eed7180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 104.805600][ T9737] ffff88808eed7200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 104.805605][ T9737] ================================================================== [ 104.805609][ T9737] Disabling lock debugging due to kernel taint [ 104.805654][ T9737] Kernel panic - not syncing: panic_on_warn set ... [ 104.805668][ T9737] CPU: 0 PID: 9737 Comm: syz-executor807 Tainted: G B 5.6.0-rc3-next-20200228-syzkaller #0 [ 104.805674][ T9737] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 104.805677][ T9737] Call Trace: [ 104.805690][ T9737] dump_stack+0x188/0x20d [ 104.805705][ T9737] panic+0x2e3/0x75c [ 104.805716][ T9737] ? add_taint.cold+0x16/0x16 [ 104.805727][ T9737] ? retint_kernel+0x2b/0x2b [ 104.805744][ T9737] ? trace_hardirqs_on+0x55/0x220 [ 104.805759][ T9737] ? con_shutdown+0x7f/0x90 [ 104.805769][ T9737] end_report+0x43/0x49 [ 104.805780][ T9737] ? con_shutdown+0x7f/0x90 [ 104.805789][ T9737] __kasan_report.cold+0xd/0x32 [ 104.805803][ T9737] ? con_shutdown+0x7f/0x90 [ 104.805817][ T9737] kasan_report+0xe/0x20 [ 104.805829][ T9737] con_shutdown+0x7f/0x90 [ 104.805839][ T9737] ? update_region+0x140/0x140 [ 104.805849][ T9737] release_tty+0xca/0x450 [ 104.805863][ T9737] tty_release_struct+0x37/0x50 [ 104.805873][ T9737] tty_release+0xbc7/0xe90 [ 104.805890][ T9737] ? do_tty_hangup+0x30/0x30 [ 104.805900][ T9737] __fput+0x2da/0x850 [ 104.805918][ T9737] task_work_run+0x13f/0x1b0 [ 104.805932][ T9737] do_exit+0xb53/0x2e10 [ 104.805949][ T9737] ? mm_update_next_owner+0x7a0/0x7a0 [ 104.805961][ T9737] ? up_read+0x1a8/0x750 [ 104.805975][ T9737] ? down_read_nested+0x430/0x430 [ 104.805987][ T9737] ? handle_mm_fault+0x29e/0x660 [ 104.806000][ T9737] do_group_exit+0x125/0x340 [ 104.806013][ T9737] __x64_sys_exit_group+0x3a/0x50 [ 104.806025][ T9737] do_syscall_64+0xf6/0x790 [ 104.806038][ T9737] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 104.806045][ T9737] RIP: 0033:0x43ff38 [ 104.806055][ T9737] Code: 00 00 be 3c 00 00 00 eb 19 66 0f 1f 84 00 00 00 00 00 48 89 d7 89 f0 0f 05 48 3d 00 f0 ff ff 77 21 f4 48 89 d7 44 89 c0 0f 05 <48> 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 0f 1f 84 00 00 00 [ 104.806061][ T9737] RSP: 002b:00007fff737ee4b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 104.806071][ T9737] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 104.806077][ T9737] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 104.806084][ T9737] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 104.806090][ T9737] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 104.806096][ T9737] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 104.807623][ T9737] Kernel Offset: disabled [ 105.578186][ T9737] Rebooting in 86400 seconds..