[ 33.243276] audit: type=1800 audit(1579941514.701:33): pid=7139 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 [ 33.270566] audit: type=1800 audit(1579941514.701:34): pid=7139 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: [ 38.370266] random: sshd: uninitialized urandom read (32 bytes read) [ 38.793832] audit: type=1400 audit(1579941520.251:35): avc: denied { map } for pid=7312 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 [ 38.877089] random: sshd: uninitialized urandom read (32 bytes read) [ 39.600133] random: sshd: uninitialized urandom read (32 bytes read) [ 39.829965] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.15.210' (ECDSA) to the list of known hosts. [ 45.424473] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program executing program [ 45.545580] audit: type=1400 audit(1579941527.001:36): avc: denied { map } for pid=7324 comm="syz-executor577" path="/root/syz-executor577899830" 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 [ 45.619453] ================================================================== [ 45.619482] BUG: KASAN: use-after-free in con_shutdown+0x85/0x90 [ 45.619488] Write of size 8 at addr ffff8880a98dcec8 by task syz-executor577/7337 [ 45.619491] [ 45.619500] CPU: 0 PID: 7337 Comm: syz-executor577 Not tainted 4.14.167-syzkaller #0 [ 45.619504] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.619507] Call Trace: [ 45.619519] dump_stack+0x142/0x197 [ 45.619528] ? con_shutdown+0x85/0x90 [ 45.619540] print_address_description.cold+0x7c/0x1dc [ 45.619548] ? con_shutdown+0x85/0x90 [ 45.619555] kasan_report.cold+0xa9/0x2af [ 45.619562] ? set_palette+0x140/0x140 [ 45.619571] __asan_report_store8_noabort+0x17/0x20 [ 45.619578] con_shutdown+0x85/0x90 [ 45.619587] release_tty+0xbf/0x7c0 [ 45.619597] tty_release_struct+0x3c/0x50 [ 45.619606] tty_release+0xaa3/0xd60 [ 45.619619] ? tty_release_struct+0x50/0x50 [ 45.619627] __fput+0x275/0x7a0 [ 45.619639] ____fput+0x16/0x20 [ 45.619647] task_work_run+0x114/0x190 [ 45.619660] do_exit+0xa1a/0x2cd0 [ 45.619673] ? mm_update_next_owner+0x5d0/0x5d0 [ 45.619686] ? up_read+0x1a/0x40 [ 45.619693] ? __do_page_fault+0x358/0xb80 [ 45.619702] do_group_exit+0x111/0x330 [ 45.619712] SyS_exit_group+0x1d/0x20 [ 45.619719] ? do_group_exit+0x330/0x330 [ 45.619728] do_syscall_64+0x1e8/0x640 [ 45.619735] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 45.619748] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 45.619755] RIP: 0033:0x43ff78 [ 45.619759] RSP: 002b:00007ffe62ef8dd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 45.619768] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff78 [ 45.619772] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 45.619777] RBP: 00000000004bf990 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 45.619781] R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000000001 [ 45.619786] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 45.619799] [ 45.619803] Allocated by task 7337: [ 45.619811] save_stack_trace+0x16/0x20 [ 45.619825] save_stack+0x45/0xd0 [ 45.619831] kasan_kmalloc+0xce/0xf0 [ 45.619836] kmem_cache_alloc_trace+0x152/0x790 [ 45.619842] vc_allocate+0x148/0x580 [ 45.619847] con_install+0x52/0x400 [ 45.619853] tty_init_dev+0xea/0x3a0 [ 45.619858] tty_open+0x414/0xa10 [ 45.619864] chrdev_open+0x207/0x590 [ 45.619872] do_dentry_open+0x73b/0xeb0 [ 45.619878] vfs_open+0x105/0x220 [ 45.619884] path_openat+0x8bd/0x3f70 [ 45.619890] do_filp_open+0x18e/0x250 [ 45.619896] do_sys_open+0x2c5/0x430 [ 45.619902] SyS_open+0x2d/0x40 [ 45.619908] do_syscall_64+0x1e8/0x640 [ 45.619914] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 45.619916] [ 45.619920] Freed by task 7339: [ 45.619925] save_stack_trace+0x16/0x20 [ 45.619931] save_stack+0x45/0xd0 [ 45.619937] kasan_slab_free+0x75/0xc0 [ 45.619944] kfree+0xcc/0x270 [ 45.619953] vt_disallocate_all+0x286/0x380 [ 45.619960] vt_ioctl+0x76b/0x2170 [ 45.619969] tty_ioctl+0x841/0x1320 [ 45.619975] do_vfs_ioctl+0x7ae/0x1060 [ 45.619981] SyS_ioctl+0x8f/0xc0 [ 45.619987] do_syscall_64+0x1e8/0x640 [ 45.619993] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 45.619996] [ 45.620006] The buggy address belongs to the object at ffff8880a98dcdc0 [ 45.620006] which belongs to the cache kmalloc-2048 of size 2048 [ 45.620012] The buggy address is located 264 bytes inside of [ 45.620012] 2048-byte region [ffff8880a98dcdc0, ffff8880a98dd5c0) [ 45.620014] The buggy address belongs to the page: [ 45.620020] page:ffffea0002a63700 count:1 mapcount:0 mapping:ffff8880a98dc540 index:0x0 compound_mapcount: 0 [ 45.620029] flags: 0xfffe0000008100(slab|head) [ 45.620038] raw: 00fffe0000008100 ffff8880a98dc540 0000000000000000 0000000100000003 [ 45.620045] raw: ffffea0002a58120 ffffea0002a763a0 ffff8880aa800c40 0000000000000000 [ 45.620048] page dumped because: kasan: bad access detected [ 45.620051] [ 45.620053] Memory state around the buggy address: [ 45.620060] ffff8880a98dcd80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 45.620065] ffff8880a98dce00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 45.620071] >ffff8880a98dce80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 45.620074] ^ [ 45.620080] ffff8880a98dcf00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 45.620086] ffff8880a98dcf80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 45.620089] ================================================================== [ 45.620091] Disabling lock debugging due to kernel taint [ 45.620224] Kernel panic - not syncing: panic_on_warn set ... [ 45.620224] [ 45.620231] CPU: 0 PID: 7337 Comm: syz-executor577 Tainted: G B 4.14.167-syzkaller #0 [ 45.620235] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.620237] Call Trace: [ 45.620243] dump_stack+0x142/0x197 [ 45.620250] ? con_shutdown+0x85/0x90 [ 45.620255] panic+0x1f9/0x42d [ 45.620260] ? add_taint.cold+0x16/0x16 [ 45.620271] kasan_end_report+0x47/0x4f [ 45.620277] kasan_report.cold+0x130/0x2af [ 45.620283] ? set_palette+0x140/0x140 [ 45.620289] __asan_report_store8_noabort+0x17/0x20 [ 45.620295] con_shutdown+0x85/0x90 [ 45.620301] release_tty+0xbf/0x7c0 [ 45.620313] tty_release_struct+0x3c/0x50 [ 45.620319] tty_release+0xaa3/0xd60 [ 45.620328] ? tty_release_struct+0x50/0x50 [ 45.620333] __fput+0x275/0x7a0 [ 45.620341] ____fput+0x16/0x20 [ 45.620346] task_work_run+0x114/0x190 [ 45.620352] do_exit+0xa1a/0x2cd0 [ 45.620359] ? mm_update_next_owner+0x5d0/0x5d0 [ 45.620365] ? up_read+0x1a/0x40 [ 45.620370] ? __do_page_fault+0x358/0xb80 [ 45.620375] do_group_exit+0x111/0x330 [ 45.620380] SyS_exit_group+0x1d/0x20 [ 45.620384] ? do_group_exit+0x330/0x330 [ 45.620389] do_syscall_64+0x1e8/0x640 [ 45.620394] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 45.620400] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 45.620404] RIP: 0033:0x43ff78 [ 45.620407] RSP: 002b:00007ffe62ef8dd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 45.620412] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff78 [ 45.620415] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 45.620418] RBP: 00000000004bf990 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 45.620421] R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000000001 [ 45.620424] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 45.621617] Kernel Offset: disabled [ 46.243666] Rebooting in 86400 seconds..