Warning: Permanently added '10.128.1.28' (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 syzkaller login: [ 97.453740][ T9400] ================================================================== [ 97.453799][ T9400] BUG: KASAN: use-after-free in con_shutdown+0x7f/0x90 [ 97.453810][ T9400] Write of size 8 at addr ffff8880922fb108 by task syz-executor741/9400 [ 97.453813][ T9400] [ 97.453827][ T9400] CPU: 1 PID: 9400 Comm: syz-executor741 Not tainted 5.6.0-rc3-next-20200228-syzkaller #0 [ 97.453835][ T9400] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 97.453839][ T9400] Call Trace: [ 97.453856][ T9400] dump_stack+0x188/0x20d [ 97.453871][ T9400] ? con_shutdown+0x7f/0x90 [ 97.453886][ T9400] ? con_shutdown+0x7f/0x90 [ 97.453902][ T9400] print_address_description.constprop.0.cold+0xd3/0x315 [ 97.453914][ T9400] ? con_shutdown+0x7f/0x90 [ 97.453929][ T9400] ? con_shutdown+0x7f/0x90 [ 97.453939][ T9400] __kasan_report.cold+0x1a/0x32 [ 97.453958][ T9400] ? con_shutdown+0x7f/0x90 [ 97.453977][ T9400] kasan_report+0xe/0x20 [ 97.453990][ T9400] con_shutdown+0x7f/0x90 [ 97.454002][ T9400] ? update_region+0x140/0x140 [ 97.454014][ T9400] release_tty+0xca/0x450 [ 97.454031][ T9400] tty_release_struct+0x37/0x50 [ 97.454046][ T9400] tty_release+0xbc7/0xe90 [ 97.454073][ T9400] ? do_tty_hangup+0x30/0x30 [ 97.454085][ T9400] __fput+0x2da/0x850 [ 97.454114][ T9400] task_work_run+0x13f/0x1b0 [ 97.454135][ T9400] do_exit+0xb53/0x2e10 [ 97.454164][ T9400] ? mm_update_next_owner+0x7a0/0x7a0 [ 97.454179][ T9400] ? up_read+0x1a8/0x750 [ 97.454205][ T9400] ? down_read_nested+0x430/0x430 [ 97.454225][ T9400] ? handle_mm_fault+0x29e/0x660 [ 97.454245][ T9400] do_group_exit+0x125/0x340 [ 97.454263][ T9400] __x64_sys_exit_group+0x3a/0x50 [ 97.454278][ T9400] do_syscall_64+0xf6/0x790 [ 97.454298][ T9400] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 97.454308][ T9400] RIP: 0033:0x43ff38 [ 97.454321][ T9400] 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 [ 97.454327][ T9400] RSP: 002b:00007ffcc29cb2f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 97.454339][ T9400] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 97.454346][ T9400] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 97.454353][ T9400] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 97.454360][ T9400] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 97.454367][ T9400] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 97.454396][ T9400] [ 97.454402][ T9400] Allocated by task 9400: [ 97.454415][ T9400] save_stack+0x1b/0x40 [ 97.454427][ T9400] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 97.454438][ T9400] kmem_cache_alloc_trace+0x153/0x7d0 [ 97.454447][ T9400] vc_allocate+0x1e2/0x6e0 [ 97.454455][ T9400] con_install+0x4f/0x400 [ 97.454466][ T9400] tty_init_dev+0xf5/0x460 [ 97.454474][ T9400] tty_open+0x47f/0xb30 [ 97.454486][ T9400] chrdev_open+0x219/0x5c0 [ 97.454497][ T9400] do_dentry_open+0x49e/0x1250 [ 97.454509][ T9400] path_openat+0x122a/0x3230 [ 97.454520][ T9400] do_filp_open+0x192/0x260 [ 97.454531][ T9400] do_sys_openat2+0x54c/0x740 [ 97.454542][ T9400] do_sys_open+0xc3/0x140 [ 97.454554][ T9400] do_syscall_64+0xf6/0x790 [ 97.454566][ T9400] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 97.454569][ T9400] [ 97.454575][ T9400] Freed by task 9402: [ 97.454585][ T9400] save_stack+0x1b/0x40 [ 97.454596][ T9400] __kasan_slab_free+0xf7/0x140 [ 97.454607][ T9400] kfree+0x109/0x2b0 [ 97.454617][ T9400] vt_disallocate_all+0x283/0x370 [ 97.454626][ T9400] vt_ioctl+0x79e/0x2450 [ 97.454636][ T9400] tty_ioctl+0xedd/0x1440 [ 97.454646][ T9400] ksys_ioctl+0x11a/0x180 [ 97.454656][ T9400] __x64_sys_ioctl+0x6f/0xb0 [ 97.454667][ T9400] do_syscall_64+0xf6/0x790 [ 97.454677][ T9400] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 97.454681][ T9400] [ 97.454688][ T9400] The buggy address belongs to the object at ffff8880922fb000 [ 97.454688][ T9400] which belongs to the cache kmalloc-2k of size 2048 [ 97.454698][ T9400] The buggy address is located 264 bytes inside of [ 97.454698][ T9400] 2048-byte region [ffff8880922fb000, ffff8880922fb800) [ 97.454702][ T9400] The buggy address belongs to the page: [ 97.454715][ T9400] page:ffffea000248bec0 refcount:1 mapcount:0 mapping:00000000d9ea4bfd index:0x0 [ 97.454724][ T9400] flags: 0xfffe0000000200(slab) [ 97.454740][ T9400] raw: 00fffe0000000200 ffffea00023c61c8 ffffea0002899588 ffff8880aa000e00 [ 97.454754][ T9400] raw: 0000000000000000 ffff8880922fb000 0000000100000001 0000000000000000 [ 97.454760][ T9400] page dumped because: kasan: bad access detected [ 97.454763][ T9400] [ 97.454767][ T9400] Memory state around the buggy address: [ 97.454776][ T9400] ffff8880922fb000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 97.454786][ T9400] ffff8880922fb080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 97.454794][ T9400] >ffff8880922fb100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 97.454799][ T9400] ^ [ 97.454807][ T9400] ffff8880922fb180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 97.454816][ T9400] ffff8880922fb200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 97.454821][ T9400] ================================================================== [ 97.454825][ T9400] Disabling lock debugging due to kernel taint [ 97.454830][ T9400] Kernel panic - not syncing: panic_on_warn set ... [ 97.454843][ T9400] CPU: 1 PID: 9400 Comm: syz-executor741 Tainted: G B 5.6.0-rc3-next-20200228-syzkaller #0 [ 97.454849][ T9400] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 97.454852][ T9400] Call Trace: [ 97.454865][ T9400] dump_stack+0x188/0x20d [ 97.454881][ T9400] panic+0x2e3/0x75c [ 97.454893][ T9400] ? add_taint.cold+0x16/0x16 [ 97.454910][ T9400] ? print_shadow_for_address+0xb8/0x114 [ 97.454920][ T9400] ? trace_hardirqs_on+0x55/0x220 [ 97.454934][ T9400] ? con_shutdown+0x7f/0x90 [ 97.454945][ T9400] end_report+0x43/0x49 [ 97.454957][ T9400] ? con_shutdown+0x7f/0x90 [ 97.454966][ T9400] __kasan_report.cold+0xd/0x32 [ 97.454980][ T9400] ? con_shutdown+0x7f/0x90 [ 97.454994][ T9400] kasan_report+0xe/0x20 [ 97.455006][ T9400] con_shutdown+0x7f/0x90 [ 97.455017][ T9400] ? update_region+0x140/0x140 [ 97.455028][ T9400] release_tty+0xca/0x450 [ 97.455042][ T9400] tty_release_struct+0x37/0x50 [ 97.455054][ T9400] tty_release+0xbc7/0xe90 [ 97.455072][ T9400] ? do_tty_hangup+0x30/0x30 [ 97.455090][ T9400] __fput+0x2da/0x850 [ 97.455109][ T9400] task_work_run+0x13f/0x1b0 [ 97.455128][ T9400] do_exit+0xb53/0x2e10 [ 97.455151][ T9400] ? mm_update_next_owner+0x7a0/0x7a0 [ 97.455163][ T9400] ? up_read+0x1a8/0x750 [ 97.455181][ T9400] ? down_read_nested+0x430/0x430 [ 97.455200][ T9400] ? handle_mm_fault+0x29e/0x660 [ 97.455213][ T9400] do_group_exit+0x125/0x340 [ 97.455226][ T9400] __x64_sys_exit_group+0x3a/0x50 [ 97.455238][ T9400] do_syscall_64+0xf6/0x790 [ 97.455252][ T9400] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 97.455261][ T9400] RIP: 0033:0x43ff38 [ 97.455273][ T9400] 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 [ 97.455280][ T9400] RSP: 002b:00007ffcc29cb2f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 97.455291][ T9400] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 97.455297][ T9400] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 97.455304][ T9400] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 97.455310][ T9400] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 97.455317][ T9400] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 97.456553][ T9400] Kernel Offset: disabled [ 98.203502][ T9400] Rebooting in 86400 seconds..