[ 33.654503] audit: type=1800 audit(1581299315.473:33): pid=7172 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed(directio)" comm="startpar" name="rc.local" dev="sda1" ino=2465 res=0 [ 33.678022] audit: type=1800 audit(1581299315.473:34): pid=7172 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed(directio)" comm="startpar" name="rmnologin" dev="sda1" ino=2456 res=0 Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 37.914942] random: sshd: uninitialized urandom read (32 bytes read) [ 38.250944] audit: type=1400 audit(1581299320.073:35): avc: denied { map } for pid=7345 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 [ 38.307786] random: sshd: uninitialized urandom read (32 bytes read) [ 39.027218] random: sshd: uninitialized urandom read (32 bytes read) [ 39.216676] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.73' (ECDSA) to the list of known hosts. [ 44.725074] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program executing program [ 44.853076] audit: type=1400 audit(1581299326.673:36): avc: denied { map } for pid=7357 comm="syz-executor030" path="/root/syz-executor030807290" 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 [ 44.905128] ================================================================== [ 44.905157] BUG: KASAN: use-after-free in con_shutdown+0x85/0x90 [ 44.905163] Write of size 8 at addr ffff88809f43a288 by task syz-executor030/7364 [ 44.905166] [ 44.905173] CPU: 1 PID: 7364 Comm: syz-executor030 Not tainted 4.14.170-syzkaller #0 [ 44.905178] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.905181] Call Trace: [ 44.905193] dump_stack+0x142/0x197 [ 44.905202] ? con_shutdown+0x85/0x90 [ 44.905211] print_address_description.cold+0x7c/0x1dc [ 44.905228] ? con_shutdown+0x85/0x90 [ 44.905235] kasan_report.cold+0xa9/0x2af [ 44.905243] ? set_palette+0x140/0x140 [ 44.905253] __asan_report_store8_noabort+0x17/0x20 [ 44.905260] con_shutdown+0x85/0x90 [ 44.905269] release_tty+0xbf/0x7c0 [ 44.905280] tty_release_struct+0x3c/0x50 [ 44.905289] tty_release+0xaa3/0xd60 [ 44.905304] ? tty_release_struct+0x50/0x50 [ 44.905311] __fput+0x275/0x7a0 [ 44.905325] ____fput+0x16/0x20 [ 44.905335] task_work_run+0x114/0x190 [ 44.905349] do_exit+0xa1a/0x2cd0 [ 44.905362] ? mm_update_next_owner+0x5d0/0x5d0 [ 44.905373] ? up_read+0x1a/0x40 [ 44.905380] ? __do_page_fault+0x358/0xb80 [ 44.905390] do_group_exit+0x111/0x330 [ 44.905400] SyS_exit_group+0x1d/0x20 [ 44.905407] ? do_group_exit+0x330/0x330 [ 44.905415] do_syscall_64+0x1e8/0x640 [ 44.905423] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 44.905436] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 44.905442] RIP: 0033:0x43ff38 [ 44.905447] RSP: 002b:00007ffcef09ad68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 44.905456] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 44.905461] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 44.905466] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 44.905470] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 44.905474] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 44.905488] [ 44.905492] Allocated by task 7364: [ 44.905500] save_stack_trace+0x16/0x20 [ 44.905513] save_stack+0x45/0xd0 [ 44.905519] kasan_kmalloc+0xce/0xf0 [ 44.905525] kmem_cache_alloc_trace+0x152/0x790 [ 44.905532] vc_allocate+0x148/0x580 [ 44.905539] con_install+0x52/0x400 [ 44.905545] tty_init_dev+0xea/0x3a0 [ 44.905551] tty_open+0x414/0xa10 [ 44.905558] chrdev_open+0x207/0x590 [ 44.905565] do_dentry_open+0x73b/0xeb0 [ 44.905571] vfs_open+0x105/0x220 [ 44.905577] path_openat+0x917/0x3e50 [ 44.905583] do_filp_open+0x18e/0x250 [ 44.905589] do_sys_open+0x2c5/0x430 [ 44.905596] SyS_open+0x2d/0x40 [ 44.905602] do_syscall_64+0x1e8/0x640 [ 44.905609] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 44.905611] [ 44.905614] Freed by task 7365: [ 44.905620] save_stack_trace+0x16/0x20 [ 44.905625] save_stack+0x45/0xd0 [ 44.905631] kasan_slab_free+0x75/0xc0 [ 44.905636] kfree+0xcc/0x270 [ 44.905642] vt_disallocate_all+0x286/0x380 [ 44.905647] vt_ioctl+0x76b/0x2170 [ 44.905653] tty_ioctl+0x841/0x1320 [ 44.905659] do_vfs_ioctl+0x7ae/0x1060 [ 44.905666] SyS_ioctl+0x8f/0xc0 [ 44.905672] do_syscall_64+0x1e8/0x640 [ 44.905678] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 44.905680] [ 44.905685] The buggy address belongs to the object at ffff88809f43a180 [ 44.905685] which belongs to the cache kmalloc-2048 of size 2048 [ 44.905691] The buggy address is located 264 bytes inside of [ 44.905691] 2048-byte region [ffff88809f43a180, ffff88809f43a980) [ 44.905694] The buggy address belongs to the page: [ 44.905700] page:ffffea00027d0e80 count:1 mapcount:0 mapping:ffff88809f43a180 index:0x0 compound_mapcount: 0 [ 44.905710] flags: 0xfffe0000008100(slab|head) [ 44.905721] raw: 00fffe0000008100 ffff88809f43a180 0000000000000000 0000000100000003 [ 44.905728] raw: ffffea000282a820 ffffea00027fb820 ffff8880aa800c40 0000000000000000 [ 44.905730] page dumped because: kasan: bad access detected [ 44.905732] [ 44.905735] Memory state around the buggy address: [ 44.905741] ffff88809f43a180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 44.905746] ffff88809f43a200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 44.905751] >ffff88809f43a280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 44.905754] ^ [ 44.905759] ffff88809f43a300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 44.905764] ffff88809f43a380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 44.905766] ================================================================== [ 44.905769] Disabling lock debugging due to kernel taint [ 44.905799] Kernel panic - not syncing: panic_on_warn set ... [ 44.905799] [ 44.905805] CPU: 1 PID: 7364 Comm: syz-executor030 Tainted: G B 4.14.170-syzkaller #0 [ 44.905808] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.905811] Call Trace: [ 44.905819] dump_stack+0x142/0x197 [ 44.905827] ? con_shutdown+0x85/0x90 [ 44.905832] panic+0x1f9/0x42d [ 44.905838] ? add_taint.cold+0x16/0x16 [ 44.905848] kasan_end_report+0x47/0x4f [ 44.905855] kasan_report.cold+0x130/0x2af [ 44.905861] ? set_palette+0x140/0x140 [ 44.905868] __asan_report_store8_noabort+0x17/0x20 [ 44.905874] con_shutdown+0x85/0x90 [ 44.905880] release_tty+0xbf/0x7c0 [ 44.905888] tty_release_struct+0x3c/0x50 [ 44.905894] tty_release+0xaa3/0xd60 [ 44.905904] ? tty_release_struct+0x50/0x50 [ 44.905909] __fput+0x275/0x7a0 [ 44.905917] ____fput+0x16/0x20 [ 44.905925] task_work_run+0x114/0x190 [ 44.905933] do_exit+0xa1a/0x2cd0 [ 44.905942] ? mm_update_next_owner+0x5d0/0x5d0 [ 44.905951] ? up_read+0x1a/0x40 [ 44.905957] ? __do_page_fault+0x358/0xb80 [ 44.905964] do_group_exit+0x111/0x330 [ 44.905972] SyS_exit_group+0x1d/0x20 [ 44.905977] ? do_group_exit+0x330/0x330 [ 44.905983] do_syscall_64+0x1e8/0x640 [ 44.905990] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 44.905998] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 44.906002] RIP: 0033:0x43ff38 [ 44.906005] RSP: 002b:00007ffcef09ad68 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 44.906011] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 44.906015] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 44.906019] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 44.906022] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 44.906026] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 44.907659] Kernel Offset: disabled