[ 41.394925] audit: type=1800 audit(1582570615.117:30): pid=7951 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 periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 45.505731] kauditd_printk_skb: 4 callbacks suppressed [ 45.505746] audit: type=1400 audit(1582570619.267:35): avc: denied { map } for pid=8127 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 '10.128.0.122' (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 [ 65.038759] audit: type=1400 audit(1582570638.797:36): avc: denied { map } for pid=8139 comm="syz-executor558" path="/root/syz-executor558689920" dev="sda1" ino=16483 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 65.128908] ================================================================== [ 65.128946] BUG: KASAN: use-after-free in con_shutdown+0x85/0x90 [ 65.128959] Write of size 8 at addr ffff888092bc0108 by task syz-executor558/8152 [ 65.128963] [ 65.128977] CPU: 1 PID: 8152 Comm: syz-executor558 Not tainted 4.19.106-syzkaller #0 [ 65.128984] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 65.128990] Call Trace: [ 65.129008] dump_stack+0x197/0x210 [ 65.129027] ? con_shutdown+0x85/0x90 [ 65.129046] print_address_description.cold+0x7c/0x20d [ 65.129059] ? con_shutdown+0x85/0x90 [ 65.129072] kasan_report.cold+0x8c/0x2ba [ 65.129086] ? set_palette+0x1c0/0x1c0 [ 65.129103] __asan_report_store8_noabort+0x17/0x20 [ 65.129115] con_shutdown+0x85/0x90 [ 65.129129] release_tty+0xe4/0x4d0 [ 65.129146] tty_release_struct+0x3c/0x50 [ 65.129169] tty_release+0xbcb/0xe90 [ 65.129191] ? tty_release_struct+0x50/0x50 [ 65.129206] __fput+0x2dd/0x8b0 [ 65.129226] ____fput+0x16/0x20 [ 65.129240] task_work_run+0x145/0x1c0 [ 65.129266] do_exit+0xc1f/0x30d0 [ 65.129291] ? mm_update_next_owner+0x660/0x660 [ 65.129307] ? up_read+0x1a/0x110 [ 65.129320] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 65.129335] ? __do_page_fault+0x484/0xe90 [ 65.129356] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 65.129372] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 65.129388] do_group_exit+0x135/0x370 [ 65.129406] __x64_sys_exit_group+0x44/0x50 [ 65.129421] do_syscall_64+0xfd/0x620 [ 65.129441] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 65.129452] RIP: 0033:0x43ff38 [ 65.129466] 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 [ 65.129474] RSP: 002b:00007fffaff639b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 65.129488] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 65.129495] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 65.129503] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 65.129511] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 65.129519] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 65.129539] [ 65.129546] Allocated by task 8148: [ 65.129560] save_stack+0x45/0xd0 [ 65.129573] kasan_kmalloc+0xce/0xf0 [ 65.129585] kmem_cache_alloc_trace+0x152/0x760 [ 65.129598] vc_allocate+0x1f5/0x760 [ 65.129610] con_install+0x52/0x410 [ 65.129622] tty_init_dev+0xf7/0x460 [ 65.129634] tty_open+0x4bf/0xb70 [ 65.129645] chrdev_open+0x245/0x6b0 [ 65.129673] do_dentry_open+0x4c3/0x1210 [ 65.129684] vfs_open+0xa0/0xd0 [ 65.129699] path_openat+0x10d8/0x44a0 [ 65.129714] do_filp_open+0x1a1/0x280 [ 65.129725] do_sys_open+0x3fe/0x550 [ 65.129736] __x64_sys_open+0x7e/0xc0 [ 65.129750] do_syscall_64+0xfd/0x620 [ 65.129764] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 65.129768] [ 65.129774] Freed by task 8151: [ 65.129786] save_stack+0x45/0xd0 [ 65.129798] __kasan_slab_free+0x102/0x150 [ 65.129811] kasan_slab_free+0xe/0x10 [ 65.129821] kfree+0xcf/0x220 [ 65.129835] vt_disallocate_all+0x2bd/0x3e0 [ 65.129848] vt_ioctl+0xc38/0x2530 [ 65.129859] tty_ioctl+0x7f3/0x1510 [ 65.129870] do_vfs_ioctl+0xd5f/0x1380 [ 65.129881] ksys_ioctl+0xab/0xd0 [ 65.129893] __x64_sys_ioctl+0x73/0xb0 [ 65.129906] do_syscall_64+0xfd/0x620 [ 65.129919] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 65.129923] [ 65.129931] The buggy address belongs to the object at ffff888092bc0000 [ 65.129931] which belongs to the cache kmalloc-2048 of size 2048 [ 65.129941] The buggy address is located 264 bytes inside of [ 65.129941] 2048-byte region [ffff888092bc0000, ffff888092bc0800) [ 65.129945] The buggy address belongs to the page: [ 65.129956] page:ffffea00024af000 count:1 mapcount:0 mapping:ffff88812c31cc40 index:0x0 compound_mapcount: 0 [ 65.129969] flags: 0xfffe0000008100(slab|head) [ 65.129985] raw: 00fffe0000008100 ffffea0002481e08 ffffea0002500308 ffff88812c31cc40 [ 65.130001] raw: 0000000000000000 ffff888092bc0000 0000000100000003 0000000000000000 [ 65.130007] page dumped because: kasan: bad access detected [ 65.130010] [ 65.130013] Memory state around the buggy address: [ 65.130024] ffff888092bc0000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.130034] ffff888092bc0080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.130045] >ffff888092bc0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.130050] ^ [ 65.130060] ffff888092bc0180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.130071] ffff888092bc0200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.130077] ================================================================== [ 65.130082] Disabling lock debugging due to kernel taint [ 65.130167] Kernel panic - not syncing: panic_on_warn set ... [ 65.130167] [ 65.130181] CPU: 1 PID: 8152 Comm: syz-executor558 Tainted: G B 4.19.106-syzkaller #0 [ 65.130189] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 65.130192] Call Trace: [ 65.130209] dump_stack+0x197/0x210 [ 65.130224] ? con_shutdown+0x85/0x90 [ 65.130239] panic+0x26a/0x50e [ 65.130254] ? __warn_printk+0xf3/0xf3 [ 65.130269] ? con_shutdown+0x85/0x90 [ 65.130284] ? preempt_schedule+0x4b/0x60 [ 65.130300] ? ___preempt_schedule+0x16/0x18 [ 65.130314] ? trace_hardirqs_on+0x5e/0x220 [ 65.130330] ? con_shutdown+0x85/0x90 [ 65.130344] kasan_end_report+0x47/0x4f [ 65.130358] kasan_report.cold+0xa9/0x2ba [ 65.130372] ? set_palette+0x1c0/0x1c0 [ 65.130388] __asan_report_store8_noabort+0x17/0x20 [ 65.130401] con_shutdown+0x85/0x90 [ 65.130414] release_tty+0xe4/0x4d0 [ 65.130428] tty_release_struct+0x3c/0x50 [ 65.130442] tty_release+0xbcb/0xe90 [ 65.130459] ? tty_release_struct+0x50/0x50 [ 65.130473] __fput+0x2dd/0x8b0 [ 65.130491] ____fput+0x16/0x20 [ 65.130503] task_work_run+0x145/0x1c0 [ 65.130518] do_exit+0xc1f/0x30d0 [ 65.130535] ? mm_update_next_owner+0x660/0x660 [ 65.130547] ? up_read+0x1a/0x110 [ 65.130558] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 65.130572] ? __do_page_fault+0x484/0xe90 [ 65.130588] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 65.130604] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 65.130618] do_group_exit+0x135/0x370 [ 65.130634] __x64_sys_exit_group+0x44/0x50 [ 65.130648] do_syscall_64+0xfd/0x620 [ 65.130665] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 65.130674] RIP: 0033:0x43ff38 [ 65.130687] 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 [ 65.130694] RSP: 002b:00007fffaff639b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 65.130707] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 65.130714] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 65.130722] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 65.130729] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 65.130736] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 65.132141] Kernel Offset: disabled [ 65.828920] Rebooting in 86400 seconds..