[ 41.991373] audit: type=1800 audit(1580571670.818:30): pid=7961 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 47.535623] kauditd_printk_skb: 4 callbacks suppressed [ 47.535639] audit: type=1400 audit(1580571676.398:35): avc: denied { map } for pid=8136 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 Warning: Permanently added '10.128.10.19' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program [ 60.616323] audit: type=1400 audit(1580571689.478:36): avc: denied { map } for pid=8148 comm="syz-executor820" path="/root/syz-executor820035381" dev="sda1" ino=16484 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 60.681662] ================================================================== [ 60.681709] BUG: KASAN: use-after-free in con_shutdown+0x85/0x90 [ 60.681721] Write of size 8 at addr ffff88808ca7e5c8 by task syz-executor820/8155 [ 60.681724] [ 60.681739] CPU: 1 PID: 8155 Comm: syz-executor820 Not tainted 4.19.101-syzkaller #0 [ 60.681748] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.681752] Call Trace: [ 60.681770] dump_stack+0x197/0x210 [ 60.681790] ? con_shutdown+0x85/0x90 [ 60.681807] print_address_description.cold+0x7c/0x20d [ 60.681823] ? con_shutdown+0x85/0x90 [ 60.681839] kasan_report.cold+0x8c/0x2ba [ 60.681855] ? set_palette+0x1c0/0x1c0 [ 60.681873] __asan_report_store8_noabort+0x17/0x20 [ 60.681886] con_shutdown+0x85/0x90 [ 60.681901] release_tty+0xe4/0x4d0 [ 60.681919] tty_release_struct+0x3c/0x50 [ 60.681935] tty_release+0xbcb/0xe90 [ 60.681957] ? tty_release_struct+0x50/0x50 [ 60.681973] __fput+0x2dd/0x8b0 [ 60.681997] ____fput+0x16/0x20 [ 60.682011] task_work_run+0x145/0x1c0 [ 60.682033] do_exit+0xc1f/0x30d0 [ 60.682059] ? mm_update_next_owner+0x660/0x660 [ 60.682073] ? up_read+0x1a/0x110 [ 60.682087] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 60.682102] ? __do_page_fault+0x484/0xe90 [ 60.682122] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 60.682139] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 60.682157] do_group_exit+0x135/0x370 [ 60.682175] __x64_sys_exit_group+0x44/0x50 [ 60.682189] do_syscall_64+0xfd/0x620 [ 60.682208] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 60.682219] RIP: 0033:0x43ff38 [ 60.682238] 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 [ 60.682246] RSP: 002b:00007ffebe29e648 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 60.682260] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 60.682268] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 60.682276] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 60.682284] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 60.682292] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 60.682311] [ 60.682317] Allocated by task 8155: [ 60.682331] save_stack+0x45/0xd0 [ 60.682343] kasan_kmalloc+0xce/0xf0 [ 60.682355] kmem_cache_alloc_trace+0x152/0x760 [ 60.682368] vc_allocate+0x1f5/0x760 [ 60.682380] con_install+0x52/0x410 [ 60.682392] tty_init_dev+0xf7/0x460 [ 60.682404] tty_open+0x4bf/0xb70 [ 60.682414] chrdev_open+0x245/0x6b0 [ 60.682425] do_dentry_open+0x4c3/0x1210 [ 60.682435] vfs_open+0xa0/0xd0 [ 60.682449] path_openat+0x1108/0x4500 [ 60.682459] do_filp_open+0x1a1/0x280 [ 60.682469] do_sys_open+0x3fe/0x550 [ 60.682481] __x64_sys_open+0x7e/0xc0 [ 60.682495] do_syscall_64+0xfd/0x620 [ 60.682509] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 60.682512] [ 60.682518] Freed by task 8156: [ 60.682528] save_stack+0x45/0xd0 [ 60.682541] __kasan_slab_free+0x102/0x150 [ 60.682553] kasan_slab_free+0xe/0x10 [ 60.682563] kfree+0xcf/0x220 [ 60.682575] vt_disallocate_all+0x2bd/0x3e0 [ 60.682587] vt_ioctl+0xc38/0x2530 [ 60.682598] tty_ioctl+0x7f3/0x1510 [ 60.682610] do_vfs_ioctl+0xd5f/0x1380 [ 60.682621] ksys_ioctl+0xab/0xd0 [ 60.682633] __x64_sys_ioctl+0x73/0xb0 [ 60.682646] do_syscall_64+0xfd/0x620 [ 60.682661] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 60.682664] [ 60.682675] The buggy address belongs to the object at ffff88808ca7e4c0 [ 60.682675] which belongs to the cache kmalloc-2048 of size 2048 [ 60.682693] The buggy address is located 264 bytes inside of [ 60.682693] 2048-byte region [ffff88808ca7e4c0, ffff88808ca7ecc0) [ 60.682698] The buggy address belongs to the page: [ 60.682710] page:ffffea0002329f80 count:1 mapcount:0 mapping:ffff88812c31cc40 index:0x0 compound_mapcount: 0 [ 60.682724] flags: 0xfffe0000008100(slab|head) [ 60.682742] raw: 00fffe0000008100 ffffea0002315588 ffffea00023ddd88 ffff88812c31cc40 [ 60.682759] raw: 0000000000000000 ffff88808ca7e4c0 0000000100000003 0000000000000000 [ 60.682765] page dumped because: kasan: bad access detected [ 60.682769] [ 60.682773] Memory state around the buggy address: [ 60.682785] ffff88808ca7e480: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 60.682796] ffff88808ca7e500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.682806] >ffff88808ca7e580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.682812] ^ [ 60.682822] ffff88808ca7e600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.682832] ffff88808ca7e680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.682837] ================================================================== [ 60.682842] Disabling lock debugging due to kernel taint [ 60.683020] Kernel panic - not syncing: panic_on_warn set ... [ 60.683020] [ 60.683035] CPU: 1 PID: 8155 Comm: syz-executor820 Tainted: G B 4.19.101-syzkaller #0 [ 60.683042] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.683045] Call Trace: [ 60.683061] dump_stack+0x197/0x210 [ 60.683076] ? con_shutdown+0x85/0x90 [ 60.683090] panic+0x26a/0x50e [ 60.683104] ? __warn_printk+0xf3/0xf3 [ 60.683116] ? con_shutdown+0x85/0x90 [ 60.683133] ? trace_hardirqs_on+0x5e/0x220 [ 60.683145] ? trace_hardirqs_on+0x5e/0x220 [ 60.683160] ? con_shutdown+0x85/0x90 [ 60.683175] kasan_end_report+0x47/0x4f [ 60.683188] kasan_report.cold+0xa9/0x2ba [ 60.683202] ? set_palette+0x1c0/0x1c0 [ 60.683218] __asan_report_store8_noabort+0x17/0x20 [ 60.683230] con_shutdown+0x85/0x90 [ 60.683243] release_tty+0xe4/0x4d0 [ 60.683258] tty_release_struct+0x3c/0x50 [ 60.683271] tty_release+0xbcb/0xe90 [ 60.683289] ? tty_release_struct+0x50/0x50 [ 60.683303] __fput+0x2dd/0x8b0 [ 60.683319] ____fput+0x16/0x20 [ 60.683332] task_work_run+0x145/0x1c0 [ 60.683347] do_exit+0xc1f/0x30d0 [ 60.683365] ? mm_update_next_owner+0x660/0x660 [ 60.683378] ? up_read+0x1a/0x110 [ 60.683390] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 60.683403] ? __do_page_fault+0x484/0xe90 [ 60.683421] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 60.683436] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 60.683451] do_group_exit+0x135/0x370 [ 60.683466] __x64_sys_exit_group+0x44/0x50 [ 60.683480] do_syscall_64+0xfd/0x620 [ 60.683496] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 60.683505] RIP: 0033:0x43ff38 [ 60.683518] 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 [ 60.683525] RSP: 002b:00007ffebe29e648 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 60.683537] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 60.683544] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 60.683552] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 60.683559] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 60.683566] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 60.684976] Kernel Offset: disabled [ 61.377601] Rebooting in 86400 seconds..