[ 47.331035] audit: type=1800 audit(1583909284.837:32): pid=7866 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="startpar" name="ssh" dev="sda1" ino=2450 res=0 Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] 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: [ 52.522451] kauditd_printk_skb: 2 callbacks suppressed [ 52.522464] audit: type=1400 audit(1583909290.097:35): avc: denied { map } for pid=8038 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 '10.128.0.148' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program [ 59.286484] audit: type=1400 audit(1583909296.867:36): avc: denied { map } for pid=8050 comm="syz-executor950" path="/root/syz-executor950397952" 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 [ 59.363805] ================================================================== [ 59.363847] BUG: KASAN: use-after-free in con_shutdown+0x7f/0x90 [ 59.363858] Write of size 8 at addr ffff88809703f808 by task syz-executor950/8058 [ 59.363862] [ 59.363875] CPU: 0 PID: 8058 Comm: syz-executor950 Not tainted 4.19.108-syzkaller #0 [ 59.363883] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.363887] Call Trace: [ 59.363909] dump_stack+0x188/0x20d [ 59.363925] ? con_shutdown+0x7f/0x90 [ 59.363942] print_address_description.cold+0x7c/0x212 [ 59.363957] ? con_shutdown+0x7f/0x90 [ 59.363968] kasan_report.cold+0x88/0x2b9 [ 59.363981] ? set_palette+0x1b0/0x1b0 [ 59.363993] con_shutdown+0x7f/0x90 [ 59.364005] release_tty+0xda/0x4c0 [ 59.364017] tty_release_struct+0x37/0x50 [ 59.364030] tty_release+0xbc7/0xe90 [ 59.364050] ? tty_release_struct+0x50/0x50 [ 59.364065] __fput+0x2cd/0x890 [ 59.364083] task_work_run+0x13f/0x1b0 [ 59.364101] do_exit+0xbcd/0x2f30 [ 59.364123] ? mm_update_next_owner+0x650/0x650 [ 59.364141] ? up_read+0x17/0x110 [ 59.364163] ? __do_page_fault+0x44e/0xdd0 [ 59.364182] do_group_exit+0x125/0x350 [ 59.364198] __x64_sys_exit_group+0x3a/0x50 [ 59.364213] do_syscall_64+0xf9/0x620 [ 59.364231] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 59.364241] RIP: 0033:0x43ff38 [ 59.364252] Code: Bad RIP value. [ 59.364260] RSP: 002b:00007ffeeb4d62e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 59.364272] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 59.364280] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 59.364288] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 59.364295] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 59.364303] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 59.364319] [ 59.364325] Allocated by task 8058: [ 59.364338] kasan_kmalloc+0xbf/0xe0 [ 59.364349] kmem_cache_alloc_trace+0x14d/0x7a0 [ 59.364360] vc_allocate+0x1db/0x6d0 [ 59.364370] con_install+0x4f/0x400 [ 59.364381] tty_init_dev+0xee/0x450 [ 59.364390] tty_open+0x4b0/0xb00 [ 59.364399] chrdev_open+0x219/0x5c0 [ 59.364408] do_dentry_open+0x4a8/0x1160 [ 59.364421] path_openat+0x1031/0x4200 [ 59.364432] do_filp_open+0x1a1/0x280 [ 59.364442] do_sys_open+0x3c0/0x500 [ 59.364453] do_syscall_64+0xf9/0x620 [ 59.364464] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 59.364467] [ 59.364472] Freed by task 8057: [ 59.364483] __kasan_slab_free+0xf7/0x140 [ 59.364492] kfree+0xce/0x220 [ 59.364506] vt_disallocate_all+0x293/0x3b0 [ 59.364518] vt_ioctl+0xb79/0x2310 [ 59.364528] tty_ioctl+0x7a1/0x1420 [ 59.364538] do_vfs_ioctl+0xcda/0x12e0 [ 59.364547] ksys_ioctl+0x9b/0xc0 [ 59.364558] __x64_sys_ioctl+0x6f/0xb0 [ 59.364570] do_syscall_64+0xf9/0x620 [ 59.364581] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 59.364584] [ 59.364593] The buggy address belongs to the object at ffff88809703f700 [ 59.364593] which belongs to the cache kmalloc-2048 of size 2048 [ 59.364604] The buggy address is located 264 bytes inside of [ 59.364604] 2048-byte region [ffff88809703f700, ffff88809703ff00) [ 59.364608] The buggy address belongs to the page: [ 59.364619] page:ffffea00025c0f80 count:1 mapcount:0 mapping:ffff88812c3dcc40 index:0x0 compound_mapcount: 0 [ 59.364632] flags: 0xfffe0000008100(slab|head) [ 59.364648] raw: 00fffe0000008100 ffffea0002626808 ffffea00025f7008 ffff88812c3dcc40 [ 59.364662] raw: 0000000000000000 ffff88809703e600 0000000100000003 0000000000000000 [ 59.364667] page dumped because: kasan: bad access detected [ 59.364670] [ 59.364674] Memory state around the buggy address: [ 59.364685] ffff88809703f700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.364694] ffff88809703f780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.364704] >ffff88809703f800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.364709] ^ [ 59.364718] ffff88809703f880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.364727] ffff88809703f900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.364732] ================================================================== [ 59.364736] Disabling lock debugging due to kernel taint [ 59.364742] Kernel panic - not syncing: panic_on_warn set ... [ 59.364742] [ 59.364754] CPU: 0 PID: 8058 Comm: syz-executor950 Tainted: G B 4.19.108-syzkaller #0 [ 59.364760] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.364763] Call Trace: [ 59.364776] dump_stack+0x188/0x20d [ 59.364791] panic+0x26a/0x50e [ 59.364803] ? __warn_printk+0xf3/0xf3 [ 59.364818] ? lock_downgrade+0x740/0x740 [ 59.364832] ? print_shadow_for_address+0xb8/0x114 [ 59.364844] ? trace_hardirqs_on+0x55/0x210 [ 59.364856] ? con_shutdown+0x7f/0x90 [ 59.364868] kasan_end_report+0x43/0x49 [ 59.364881] kasan_report.cold+0xa4/0x2b9 [ 59.364893] ? set_palette+0x1b0/0x1b0 [ 59.364905] con_shutdown+0x7f/0x90 [ 59.364914] release_tty+0xda/0x4c0 [ 59.364926] tty_release_struct+0x37/0x50 [ 59.364938] tty_release+0xbc7/0xe90 [ 59.364953] ? tty_release_struct+0x50/0x50 [ 59.364965] __fput+0x2cd/0x890 [ 59.364980] task_work_run+0x13f/0x1b0 [ 59.364993] do_exit+0xbcd/0x2f30 [ 59.365009] ? mm_update_next_owner+0x650/0x650 [ 59.365022] ? up_read+0x17/0x110 [ 59.365035] ? __do_page_fault+0x44e/0xdd0 [ 59.365049] do_group_exit+0x125/0x350 [ 59.365062] __x64_sys_exit_group+0x3a/0x50 [ 59.365074] do_syscall_64+0xf9/0x620 [ 59.365088] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 59.365096] RIP: 0033:0x43ff38 [ 59.365105] Code: Bad RIP value. [ 59.365111] RSP: 002b:00007ffeeb4d62e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 59.365123] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 59.365129] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 59.365136] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 59.365143] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 59.365158] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 59.366522] Kernel Offset: disabled [ 59.951534] Rebooting in 86400 seconds..