[?25l[?1c7[ ok 8[?25h[?0c[ 33.629848] audit: type=1800 audit(1583641558.539:34): pid=7147 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: [ 36.194594] random: sshd: uninitialized urandom read (32 bytes read) [ 36.402264] audit: type=1400 audit(1583641561.349:35): avc: denied { map } for pid=7321 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 [ 36.446810] random: sshd: uninitialized urandom read (32 bytes read) [ 37.181602] random: sshd: uninitialized urandom read (32 bytes read) [ 44.723635] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.108' (ECDSA) to the list of known hosts. [ 50.249776] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program [ 50.374837] audit: type=1400 audit(1583641575.319:36): avc: denied { map } for pid=7333 comm="syz-executor122" path="/root/syz-executor122843340" 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 [ 50.429585] ================================================================== [ 50.429611] BUG: KASAN: use-after-free in con_shutdown+0x7f/0x90 [ 50.429616] Write of size 8 at addr ffff888095568408 by task syz-executor122/7341 [ 50.429618] [ 50.429625] CPU: 1 PID: 7341 Comm: syz-executor122 Not tainted 4.14.172-syzkaller #0 [ 50.429628] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.429630] Call Trace: [ 50.429640] dump_stack+0x13e/0x194 [ 50.429647] ? con_shutdown+0x7f/0x90 [ 50.429656] print_address_description.cold+0x7c/0x1e2 [ 50.429662] ? con_shutdown+0x7f/0x90 [ 50.429668] kasan_report.cold+0xa9/0x2ae [ 50.429674] ? set_palette+0x130/0x130 [ 50.429680] con_shutdown+0x7f/0x90 [ 50.429686] release_tty+0xb6/0x7a0 [ 50.429693] tty_release_struct+0x37/0x50 [ 50.429699] tty_release+0xaa6/0xd60 [ 50.429709] ? tty_release_struct+0x50/0x50 [ 50.429714] __fput+0x25f/0x790 [ 50.429726] task_work_run+0x113/0x190 [ 50.429735] do_exit+0x9f2/0x2b00 [ 50.429743] ? __do_page_fault+0x4e4/0xb40 [ 50.429750] ? mm_update_next_owner+0x5b0/0x5b0 [ 50.429758] ? lock_downgrade+0x6e0/0x6e0 [ 50.429768] do_group_exit+0x100/0x310 [ 50.429775] SyS_exit_group+0x19/0x20 [ 50.429780] ? do_group_exit+0x310/0x310 [ 50.429787] do_syscall_64+0x1d5/0x640 [ 50.429797] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 50.429803] RIP: 0033:0x43ff38 [ 50.429806] RSP: 002b:00007ffeae5dc278 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 50.429813] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 50.429816] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 50.429819] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 50.429823] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 50.429832] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 50.429841] [ 50.429844] Allocated by task 7341: [ 50.429850] save_stack+0x32/0xa0 [ 50.429854] kasan_kmalloc+0xbf/0xe0 [ 50.429858] kmem_cache_alloc_trace+0x14d/0x7b0 [ 50.429863] vc_allocate+0x142/0x550 [ 50.429867] con_install+0x4f/0x3e0 [ 50.429872] tty_init_dev+0xe1/0x3a0 [ 50.429876] tty_open+0x410/0x9c0 [ 50.429881] chrdev_open+0x1fc/0x540 [ 50.429887] do_dentry_open+0x732/0xe90 [ 50.429893] vfs_open+0x105/0x220 [ 50.429899] path_openat+0x8ca/0x3c50 [ 50.429905] do_filp_open+0x18e/0x250 [ 50.429911] do_sys_open+0x29d/0x3f0 [ 50.429917] do_syscall_64+0x1d5/0x640 [ 50.429923] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 50.429925] [ 50.429928] Freed by task 7340: [ 50.429934] save_stack+0x32/0xa0 [ 50.429940] kasan_slab_free+0x75/0xc0 [ 50.429945] kfree+0xcb/0x260 [ 50.429953] vt_disallocate_all+0x25c/0x340 [ 50.429958] vt_ioctl+0x6e3/0x1f00 [ 50.429964] tty_ioctl+0x6c5/0x1220 [ 50.429970] do_vfs_ioctl+0x75a/0xfe0 [ 50.429976] SyS_ioctl+0x7f/0xb0 [ 50.429982] do_syscall_64+0x1d5/0x640 [ 50.429989] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 50.429991] [ 50.429996] The buggy address belongs to the object at ffff888095568300 [ 50.429996] which belongs to the cache kmalloc-2048 of size 2048 [ 50.430002] The buggy address is located 264 bytes inside of [ 50.430002] 2048-byte region [ffff888095568300, ffff888095568b00) [ 50.430004] The buggy address belongs to the page: [ 50.430010] page:ffffea0002555a00 count:1 mapcount:0 mapping:ffff888095568300 index:0x0 compound_mapcount: 0 [ 50.430019] flags: 0xfffe0000008100(slab|head) [ 50.430028] raw: 00fffe0000008100 ffff888095568300 0000000000000000 0000000100000003 [ 50.430035] raw: ffffea00024f23a0 ffffea000254c1a0 ffff88812fe56c40 0000000000000000 [ 50.430038] page dumped because: kasan: bad access detected [ 50.430040] [ 50.430042] Memory state around the buggy address: [ 50.430048] ffff888095568300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 50.430052] ffff888095568380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 50.430057] >ffff888095568400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 50.430060] ^ [ 50.430065] ffff888095568480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 50.430070] ffff888095568500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 50.430073] ================================================================== [ 50.430075] Disabling lock debugging due to kernel taint [ 50.430258] Kernel panic - not syncing: panic_on_warn set ... [ 50.430258] [ 50.430263] CPU: 1 PID: 7341 Comm: syz-executor122 Tainted: G B 4.14.172-syzkaller #0 [ 50.430267] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.430268] Call Trace: [ 50.430280] dump_stack+0x13e/0x194 [ 50.430286] panic+0x1f9/0x42d [ 50.430291] ? add_taint.cold+0x16/0x16 [ 50.430298] ? con_shutdown+0x7f/0x90 [ 50.430303] kasan_end_report+0x43/0x49 [ 50.430308] kasan_report.cold+0x12f/0x2ae [ 50.430313] ? set_palette+0x130/0x130 [ 50.430318] con_shutdown+0x7f/0x90 [ 50.430323] release_tty+0xb6/0x7a0 [ 50.430329] tty_release_struct+0x37/0x50 [ 50.430334] tty_release+0xaa6/0xd60 [ 50.430341] ? tty_release_struct+0x50/0x50 [ 50.430345] __fput+0x25f/0x790 [ 50.430353] task_work_run+0x113/0x190 [ 50.430360] do_exit+0x9f2/0x2b00 [ 50.430365] ? __do_page_fault+0x4e4/0xb40 [ 50.430371] ? mm_update_next_owner+0x5b0/0x5b0 [ 50.430376] ? lock_downgrade+0x6e0/0x6e0 [ 50.430384] do_group_exit+0x100/0x310 [ 50.430389] SyS_exit_group+0x19/0x20 [ 50.430393] ? do_group_exit+0x310/0x310 [ 50.430398] do_syscall_64+0x1d5/0x640 [ 50.430405] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 50.430408] RIP: 0033:0x43ff38 [ 50.430411] RSP: 002b:00007ffeae5dc278 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 50.430416] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 50.430419] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 50.430422] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 50.430425] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 50.430427] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 50.431650] Kernel Offset: disabled [ 51.027768] Rebooting in 86400 seconds..