Warning: Permanently added '10.128.0.230' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program syzkaller login: [ 527.339684][ T7053] ================================================================== [ 527.339873][ T7053] BUG: KASAN: use-after-free in con_shutdown+0x7f/0x90 [ 527.339884][ T7053] Write of size 8 at addr ffff8880a31f0108 by task syz-executor600/7053 [ 527.339887][ T7053] [ 527.339901][ T7053] CPU: 0 PID: 7053 Comm: syz-executor600 Not tainted 5.6.0-rc7-syzkaller #0 [ 527.339907][ T7053] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 527.339919][ T7053] Call Trace: [ 527.340042][ T7053] dump_stack+0x188/0x20d [ 527.340057][ T7053] ? con_shutdown+0x7f/0x90 [ 527.340069][ T7053] ? con_shutdown+0x7f/0x90 [ 527.340148][ T7053] print_address_description.constprop.0.cold+0xd3/0x315 [ 527.340160][ T7053] ? con_shutdown+0x7f/0x90 [ 527.340173][ T7053] ? con_shutdown+0x7f/0x90 [ 527.340184][ T7053] __kasan_report.cold+0x1a/0x32 [ 527.340202][ T7053] ? con_shutdown+0x7f/0x90 [ 527.340220][ T7053] kasan_report+0xe/0x20 [ 527.340231][ T7053] con_shutdown+0x7f/0x90 [ 527.340240][ T7053] ? update_region+0x140/0x140 [ 527.340284][ T7053] release_tty+0xca/0x450 [ 527.340301][ T7053] tty_release_struct+0x37/0x50 [ 527.340314][ T7053] tty_release+0xbc7/0xe90 [ 527.340342][ T7053] ? do_tty_hangup+0x30/0x30 [ 527.340372][ T7053] __fput+0x2da/0x850 [ 527.340426][ T7053] task_work_run+0x13f/0x1b0 [ 527.340502][ T7053] do_exit+0xb34/0x2dd0 [ 527.340535][ T7053] ? mm_update_next_owner+0x7a0/0x7a0 [ 527.340596][ T7053] ? up_read+0x1ab/0x750 [ 527.340611][ T7053] ? mark_held_locks+0x9f/0xe0 [ 527.340627][ T7053] ? down_read_non_owner+0x470/0x470 [ 527.340706][ T7053] ? handle_mm_fault+0x491/0xa10 [ 527.340725][ T7053] do_group_exit+0x125/0x340 [ 527.340743][ T7053] __x64_sys_exit_group+0x3a/0x50 [ 527.340789][ T7053] do_syscall_64+0xf6/0x7d0 [ 527.340857][ T7053] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 527.340867][ T7053] RIP: 0033:0x43ff38 [ 527.340880][ T7053] 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 [ 527.340886][ T7053] RSP: 002b:00007ffdd06411b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 527.340898][ T7053] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 527.340906][ T7053] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 527.340921][ T7053] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 527.340928][ T7053] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 527.340935][ T7053] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 527.340965][ T7053] [ 527.340972][ T7053] Allocated by task 7053: [ 527.340985][ T7053] save_stack+0x1b/0x80 [ 527.340996][ T7053] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 527.341007][ T7053] kmem_cache_alloc_trace+0x153/0x7d0 [ 527.341018][ T7053] vc_allocate+0x1e2/0x6e0 [ 527.341028][ T7053] con_install+0x4f/0x400 [ 527.341039][ T7053] tty_init_dev+0xf5/0x460 [ 527.341048][ T7053] tty_open+0x47f/0xb30 [ 527.341059][ T7053] chrdev_open+0x219/0x5c0 [ 527.341096][ T7053] do_dentry_open+0x4a2/0x1250 [ 527.341125][ T7053] path_openat+0x122a/0x32b0 [ 527.341134][ T7053] do_filp_open+0x192/0x260 [ 527.341142][ T7053] do_sys_openat2+0x54c/0x740 [ 527.341152][ T7053] do_sys_open+0xc3/0x140 [ 527.341162][ T7053] do_syscall_64+0xf6/0x7d0 [ 527.341172][ T7053] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 527.341175][ T7053] [ 527.341180][ T7053] Freed by task 7051: [ 527.341189][ T7053] save_stack+0x1b/0x80 [ 527.341199][ T7053] __kasan_slab_free+0xf7/0x140 [ 527.341207][ T7053] kfree+0x109/0x2b0 [ 527.341219][ T7053] vt_disallocate_all+0x293/0x3b0 [ 527.341230][ T7053] vt_ioctl+0xb79/0x2470 [ 527.341240][ T7053] tty_ioctl+0xedd/0x1440 [ 527.341251][ T7053] ksys_ioctl+0x11a/0x180 [ 527.341262][ T7053] __x64_sys_ioctl+0x6f/0xb0 [ 527.341274][ T7053] do_syscall_64+0xf6/0x7d0 [ 527.341285][ T7053] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 527.341289][ T7053] [ 527.341298][ T7053] The buggy address belongs to the object at ffff8880a31f0000 [ 527.341298][ T7053] which belongs to the cache kmalloc-2k of size 2048 [ 527.341309][ T7053] The buggy address is located 264 bytes inside of [ 527.341309][ T7053] 2048-byte region [ffff8880a31f0000, ffff8880a31f0800) [ 527.341313][ T7053] The buggy address belongs to the page: [ 527.341325][ T7053] page:ffffea00028c7c00 refcount:1 mapcount:0 mapping:ffff8880aa000e00 index:0x0 [ 527.341335][ T7053] flags: 0xfffe0000000200(slab) [ 527.341352][ T7053] raw: 00fffe0000000200 ffffea0002a17408 ffffea00028eff08 ffff8880aa000e00 [ 527.341366][ T7053] raw: 0000000000000000 ffff8880a31f0000 0000000100000001 0000000000000000 [ 527.341372][ T7053] page dumped because: kasan: bad access detected [ 527.341375][ T7053] [ 527.341379][ T7053] Memory state around the buggy address: [ 527.341389][ T7053] ffff8880a31f0000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 527.341399][ T7053] ffff8880a31f0080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 527.341409][ T7053] >ffff8880a31f0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 527.341413][ T7053] ^ [ 527.341423][ T7053] ffff8880a31f0180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 527.341433][ T7053] ffff8880a31f0200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 527.341437][ T7053] ================================================================== [ 527.341441][ T7053] Disabling lock debugging due to kernel taint [ 527.341477][ T7053] Kernel panic - not syncing: panic_on_warn set ... [ 527.341491][ T7053] CPU: 0 PID: 7053 Comm: syz-executor600 Tainted: G B 5.6.0-rc7-syzkaller #0 [ 527.341498][ T7053] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 527.341501][ T7053] Call Trace: [ 527.341515][ T7053] dump_stack+0x188/0x20d [ 527.341530][ T7053] panic+0x2e3/0x75c [ 527.341542][ T7053] ? add_taint.cold+0x16/0x16 [ 527.341553][ T7053] ? retint_kernel+0x2b/0x2b [ 527.341635][ T7053] ? trace_hardirqs_on+0x55/0x220 [ 527.341650][ T7053] ? con_shutdown+0x7f/0x90 [ 527.341662][ T7053] end_report+0x43/0x49 [ 527.341672][ T7053] ? con_shutdown+0x7f/0x90 [ 527.341684][ T7053] __kasan_report.cold+0xd/0x32 [ 527.341696][ T7053] ? con_shutdown+0x7f/0x90 [ 527.341709][ T7053] kasan_report+0xe/0x20 [ 527.341722][ T7053] con_shutdown+0x7f/0x90 [ 527.341732][ T7053] ? update_region+0x140/0x140 [ 527.341742][ T7053] release_tty+0xca/0x450 [ 527.341755][ T7053] tty_release_struct+0x37/0x50 [ 527.341767][ T7053] tty_release+0xbc7/0xe90 [ 527.341785][ T7053] ? do_tty_hangup+0x30/0x30 [ 527.341794][ T7053] __fput+0x2da/0x850 [ 527.341813][ T7053] task_work_run+0x13f/0x1b0 [ 527.341829][ T7053] do_exit+0xb34/0x2dd0 [ 527.341851][ T7053] ? mm_update_next_owner+0x7a0/0x7a0 [ 527.341863][ T7053] ? up_read+0x1ab/0x750 [ 527.341875][ T7053] ? mark_held_locks+0x9f/0xe0 [ 527.341888][ T7053] ? down_read_non_owner+0x470/0x470 [ 527.341904][ T7053] ? handle_mm_fault+0x491/0xa10 [ 527.341923][ T7053] do_group_exit+0x125/0x340 [ 527.341937][ T7053] __x64_sys_exit_group+0x3a/0x50 [ 527.341949][ T7053] do_syscall_64+0xf6/0x7d0 [ 527.341964][ T7053] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 527.341972][ T7053] RIP: 0033:0x43ff38 [ 527.341983][ T7053] 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 [ 527.341989][ T7053] RSP: 002b:00007ffdd06411b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 527.342001][ T7053] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 527.342007][ T7053] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 527.342014][ T7053] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 527.342019][ T7053] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 527.342024][ T7053] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 527.343576][ T7053] Kernel Offset: disabled [ 528.116498][ T7053] Rebooting in 86400 seconds..