Warning: Permanently added '10.128.1.23' (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 syzkaller login: [ 82.144304][ T9467] ================================================================== [ 82.144364][ T9467] BUG: KASAN: use-after-free in con_shutdown+0x7f/0x90 [ 82.144376][ T9467] Write of size 8 at addr ffff88809e67f108 by task syz-executor869/9467 [ 82.144379][ T9467] [ 82.144393][ T9467] CPU: 1 PID: 9467 Comm: syz-executor869 Not tainted 5.6.0-rc3-next-20200228-syzkaller #0 [ 82.144401][ T9467] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 82.144405][ T9467] Call Trace: [ 82.144428][ T9467] dump_stack+0x188/0x20d [ 82.144442][ T9467] ? con_shutdown+0x7f/0x90 [ 82.144456][ T9467] ? con_shutdown+0x7f/0x90 [ 82.144473][ T9467] print_address_description.constprop.0.cold+0xd3/0x315 [ 82.144485][ T9467] ? con_shutdown+0x7f/0x90 [ 82.144498][ T9467] ? con_shutdown+0x7f/0x90 [ 82.144508][ T9467] __kasan_report.cold+0x1a/0x32 [ 82.144526][ T9467] ? con_shutdown+0x7f/0x90 [ 82.144545][ T9467] kasan_report+0xe/0x20 [ 82.144558][ T9467] con_shutdown+0x7f/0x90 [ 82.144570][ T9467] ? update_region+0x140/0x140 [ 82.144590][ T9467] release_tty+0xca/0x450 [ 82.144608][ T9467] tty_release_struct+0x37/0x50 [ 82.144622][ T9467] tty_release+0xbc7/0xe90 [ 82.144650][ T9467] ? do_tty_hangup+0x30/0x30 [ 82.144667][ T9467] __fput+0x2da/0x850 [ 82.144695][ T9467] task_work_run+0x13f/0x1b0 [ 82.144716][ T9467] do_exit+0xb53/0x2e10 [ 82.144745][ T9467] ? mm_update_next_owner+0x7a0/0x7a0 [ 82.144758][ T9467] ? up_read+0x1a8/0x750 [ 82.144776][ T9467] ? down_read_nested+0x430/0x430 [ 82.144794][ T9467] ? handle_mm_fault+0x29e/0x660 [ 82.144812][ T9467] do_group_exit+0x125/0x340 [ 82.144831][ T9467] __x64_sys_exit_group+0x3a/0x50 [ 82.144846][ T9467] do_syscall_64+0xf6/0x790 [ 82.144866][ T9467] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 82.144876][ T9467] RIP: 0033:0x43ff38 [ 82.144889][ T9467] 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 [ 82.144896][ T9467] RSP: 002b:00007ffef84bece8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 82.144909][ T9467] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 82.144916][ T9467] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 82.144923][ T9467] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 82.144930][ T9467] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 82.144937][ T9467] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 82.144966][ T9467] [ 82.144973][ T9467] Allocated by task 9467: [ 82.144985][ T9467] save_stack+0x1b/0x40 [ 82.144997][ T9467] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 82.145009][ T9467] kmem_cache_alloc_trace+0x153/0x7d0 [ 82.145018][ T9467] vc_allocate+0x1e2/0x6e0 [ 82.145027][ T9467] con_install+0x4f/0x400 [ 82.145039][ T9467] tty_init_dev+0xf5/0x460 [ 82.145047][ T9467] tty_open+0x47f/0xb30 [ 82.145058][ T9467] chrdev_open+0x219/0x5c0 [ 82.145070][ T9467] do_dentry_open+0x49e/0x1250 [ 82.145083][ T9467] path_openat+0x122a/0x3230 [ 82.145094][ T9467] do_filp_open+0x192/0x260 [ 82.145105][ T9467] do_sys_openat2+0x54c/0x740 [ 82.145116][ T9467] do_sys_open+0xc3/0x140 [ 82.145127][ T9467] do_syscall_64+0xf6/0x790 [ 82.145138][ T9467] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 82.145141][ T9467] [ 82.145146][ T9467] Freed by task 9466: [ 82.145156][ T9467] save_stack+0x1b/0x40 [ 82.145167][ T9467] __kasan_slab_free+0xf7/0x140 [ 82.145177][ T9467] kfree+0x109/0x2b0 [ 82.145186][ T9467] vt_disallocate_all+0x283/0x370 [ 82.145195][ T9467] vt_ioctl+0x79e/0x2450 [ 82.145207][ T9467] tty_ioctl+0xedd/0x1440 [ 82.145216][ T9467] ksys_ioctl+0x11a/0x180 [ 82.145226][ T9467] __x64_sys_ioctl+0x6f/0xb0 [ 82.145237][ T9467] do_syscall_64+0xf6/0x790 [ 82.145247][ T9467] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 82.145251][ T9467] [ 82.145259][ T9467] The buggy address belongs to the object at ffff88809e67f000 [ 82.145259][ T9467] which belongs to the cache kmalloc-2k of size 2048 [ 82.145270][ T9467] The buggy address is located 264 bytes inside of [ 82.145270][ T9467] 2048-byte region [ffff88809e67f000, ffff88809e67f800) [ 82.145274][ T9467] The buggy address belongs to the page: [ 82.145286][ T9467] page:ffffea0002799fc0 refcount:1 mapcount:0 mapping:0000000031829653 index:0x0 [ 82.145295][ T9467] flags: 0xfffe0000000200(slab) [ 82.145312][ T9467] raw: 00fffe0000000200 ffffea00027dce48 ffffea00028d4bc8 ffff8880aa000e00 [ 82.145326][ T9467] raw: 0000000000000000 ffff88809e67f000 0000000100000001 0000000000000000 [ 82.145330][ T9467] page dumped because: kasan: bad access detected [ 82.145334][ T9467] [ 82.145338][ T9467] Memory state around the buggy address: [ 82.145348][ T9467] ffff88809e67f000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 82.145358][ T9467] ffff88809e67f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 82.145367][ T9467] >ffff88809e67f100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 82.145372][ T9467] ^ [ 82.145381][ T9467] ffff88809e67f180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 82.145391][ T9467] ffff88809e67f200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 82.145396][ T9467] ================================================================== [ 82.145400][ T9467] Disabling lock debugging due to kernel taint [ 82.148584][ T9467] Kernel panic - not syncing: panic_on_warn set ... [ 82.148600][ T9467] CPU: 1 PID: 9467 Comm: syz-executor869 Tainted: G B 5.6.0-rc3-next-20200228-syzkaller #0 [ 82.148607][ T9467] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 82.148610][ T9467] Call Trace: [ 82.148628][ T9467] dump_stack+0x188/0x20d [ 82.148644][ T9467] panic+0x2e3/0x75c [ 82.148656][ T9467] ? add_taint.cold+0x16/0x16 [ 82.148673][ T9467] ? preempt_schedule_common+0x5e/0xc0 [ 82.148687][ T9467] ? con_shutdown+0x7f/0x90 [ 82.148700][ T9467] ? ___preempt_schedule+0x16/0x18 [ 82.148712][ T9467] ? trace_hardirqs_on+0x55/0x220 [ 82.148726][ T9467] ? con_shutdown+0x7f/0x90 [ 82.148737][ T9467] end_report+0x43/0x49 [ 82.148749][ T9467] ? con_shutdown+0x7f/0x90 [ 82.148758][ T9467] __kasan_report.cold+0xd/0x32 [ 82.148771][ T9467] ? con_shutdown+0x7f/0x90 [ 82.148786][ T9467] kasan_report+0xe/0x20 [ 82.148798][ T9467] con_shutdown+0x7f/0x90 [ 82.148810][ T9467] ? update_region+0x140/0x140 [ 82.148822][ T9467] release_tty+0xca/0x450 [ 82.148836][ T9467] tty_release_struct+0x37/0x50 [ 82.148848][ T9467] tty_release+0xbc7/0xe90 [ 82.148866][ T9467] ? do_tty_hangup+0x30/0x30 [ 82.148878][ T9467] __fput+0x2da/0x850 [ 82.148897][ T9467] task_work_run+0x13f/0x1b0 [ 82.148911][ T9467] do_exit+0xb53/0x2e10 [ 82.148929][ T9467] ? mm_update_next_owner+0x7a0/0x7a0 [ 82.148941][ T9467] ? up_read+0x1a8/0x750 [ 82.148956][ T9467] ? down_read_nested+0x430/0x430 [ 82.148970][ T9467] ? handle_mm_fault+0x29e/0x660 [ 82.148983][ T9467] do_group_exit+0x125/0x340 [ 82.148996][ T9467] __x64_sys_exit_group+0x3a/0x50 [ 82.149009][ T9467] do_syscall_64+0xf6/0x790 [ 82.149023][ T9467] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 82.149032][ T9467] RIP: 0033:0x43ff38 [ 82.149043][ T9467] 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 [ 82.149050][ T9467] RSP: 002b:00007ffef84bece8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 82.149061][ T9467] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 82.149067][ T9467] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 82.149074][ T9467] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 82.149080][ T9467] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 82.149087][ T9467] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 82.150842][ T9467] Kernel Offset: disabled [ 82.922993][ T9467] Rebooting in 86400 seconds..