[ 35.439286] audit: type=1800 audit(1582272201.581:33): pid=7197 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 [ 35.467803] audit: type=1800 audit(1582272201.591:34): pid=7197 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: [ 37.035844] random: sshd: uninitialized urandom read (32 bytes read) [ 37.296520] audit: type=1400 audit(1582272203.441:35): avc: denied { map } for pid=7368 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 [ 37.347037] random: sshd: uninitialized urandom read (32 bytes read) [ 38.063739] random: sshd: uninitialized urandom read (32 bytes read) [ 38.246228] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.6' (ECDSA) to the list of known hosts. [ 43.772872] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program executing program [ 43.899905] audit: type=1400 audit(1582272210.041:36): avc: denied { map } for pid=7380 comm="syz-executor904" path="/root/syz-executor904839436" 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 [ 43.962208] ================================================================== [ 43.962237] BUG: KASAN: use-after-free in con_shutdown+0x85/0x90 [ 43.962243] Write of size 8 at addr ffff8880a13829c8 by task syz-executor904/7393 [ 43.962245] [ 43.962254] CPU: 1 PID: 7393 Comm: syz-executor904 Not tainted 4.14.171-syzkaller #0 [ 43.962259] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.962262] Call Trace: [ 43.962272] dump_stack+0x142/0x197 [ 43.962283] ? con_shutdown+0x85/0x90 [ 43.962294] print_address_description.cold+0x7c/0x1dc [ 43.962303] ? con_shutdown+0x85/0x90 [ 43.962310] kasan_report.cold+0xa9/0x2af [ 43.962317] ? set_palette+0x140/0x140 [ 43.962327] __asan_report_store8_noabort+0x17/0x20 [ 43.962334] con_shutdown+0x85/0x90 [ 43.962342] release_tty+0xbf/0x7c0 [ 43.962352] tty_release_struct+0x3c/0x50 [ 43.962361] tty_release+0xaa3/0xd60 [ 43.962375] ? tty_release_struct+0x50/0x50 [ 43.962383] __fput+0x275/0x7a0 [ 43.962396] ____fput+0x16/0x20 [ 43.962405] task_work_run+0x114/0x190 [ 43.962417] do_exit+0xa1a/0x2cd0 [ 43.962431] ? mm_update_next_owner+0x5d0/0x5d0 [ 43.962443] ? up_read+0x1a/0x40 [ 43.962451] ? __do_page_fault+0x358/0xb80 [ 43.962459] do_group_exit+0x111/0x330 [ 43.962469] SyS_exit_group+0x1d/0x20 [ 43.962475] ? do_group_exit+0x330/0x330 [ 43.962483] do_syscall_64+0x1e8/0x640 [ 43.962491] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 43.962504] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 43.962510] RIP: 0033:0x43ff38 [ 43.962515] RSP: 002b:00007ffe90b1e3f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 43.962524] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 43.962529] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 43.962533] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 43.962538] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 43.962542] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 43.962555] [ 43.962558] Allocated by task 7393: [ 43.962567] save_stack_trace+0x16/0x20 [ 43.962572] save_stack+0x45/0xd0 [ 43.962578] kasan_kmalloc+0xce/0xf0 [ 43.962584] kmem_cache_alloc_trace+0x152/0x790 [ 43.962590] vc_allocate+0x148/0x580 [ 43.962596] con_install+0x52/0x400 [ 43.962602] tty_init_dev+0xea/0x3a0 [ 43.962608] tty_open+0x414/0xa10 [ 43.962615] chrdev_open+0x207/0x590 [ 43.962621] do_dentry_open+0x73b/0xeb0 [ 43.962627] vfs_open+0x105/0x220 [ 43.962633] path_openat+0x917/0x3e50 [ 43.962639] do_filp_open+0x18e/0x250 [ 43.962645] do_sys_open+0x2c5/0x430 [ 43.962651] SyS_open+0x2d/0x40 [ 43.962657] do_syscall_64+0x1e8/0x640 [ 43.962664] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 43.962666] [ 43.962670] Freed by task 7392: [ 43.962676] save_stack_trace+0x16/0x20 [ 43.962681] save_stack+0x45/0xd0 [ 43.962687] kasan_slab_free+0x75/0xc0 [ 43.962691] kfree+0xcc/0x270 [ 43.962699] vt_disallocate_all+0x286/0x380 [ 43.962704] vt_ioctl+0x76b/0x2170 [ 43.962710] tty_ioctl+0x841/0x1320 [ 43.962717] do_vfs_ioctl+0x7ae/0x1060 [ 43.962723] SyS_ioctl+0x8f/0xc0 [ 43.962736] do_syscall_64+0x1e8/0x640 [ 43.962743] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 43.962745] [ 43.962751] The buggy address belongs to the object at ffff8880a13828c0 [ 43.962751] which belongs to the cache kmalloc-2048 of size 2048 [ 43.962757] The buggy address is located 264 bytes inside of [ 43.962757] 2048-byte region [ffff8880a13828c0, ffff8880a13830c0) [ 43.962760] The buggy address belongs to the page: [ 43.962766] page:ffffea000284e080 count:1 mapcount:0 mapping:ffff8880a1382040 index:0x0 compound_mapcount: 0 [ 43.962777] flags: 0xfffe0000008100(slab|head) [ 43.962786] raw: 00fffe0000008100 ffff8880a1382040 0000000000000000 0000000100000003 [ 43.962794] raw: ffffea0001be8820 ffffea00025776a0 ffff8880aa800c40 0000000000000000 [ 43.962798] page dumped because: kasan: bad access detected [ 43.962800] [ 43.962802] Memory state around the buggy address: [ 43.962808] ffff8880a1382880: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 43.962814] ffff8880a1382900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 43.962819] >ffff8880a1382980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 43.962823] ^ [ 43.962829] ffff8880a1382a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 43.962835] ffff8880a1382a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 43.962838] ================================================================== [ 43.962841] Disabling lock debugging due to kernel taint [ 43.962844] Kernel panic - not syncing: panic_on_warn set ... [ 43.962844] [ 43.962851] CPU: 1 PID: 7393 Comm: syz-executor904 Tainted: G B 4.14.171-syzkaller #0 [ 43.962855] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.962857] Call Trace: [ 43.962865] dump_stack+0x142/0x197 [ 43.962872] ? con_shutdown+0x85/0x90 [ 43.962878] panic+0x1f9/0x42d [ 43.962883] ? add_taint.cold+0x16/0x16 [ 43.962891] ? lock_downgrade+0x740/0x740 [ 43.962901] kasan_end_report+0x47/0x4f [ 43.962908] kasan_report.cold+0x130/0x2af [ 43.962914] ? set_palette+0x140/0x140 [ 43.962922] __asan_report_store8_noabort+0x17/0x20 [ 43.962928] con_shutdown+0x85/0x90 [ 43.962935] release_tty+0xbf/0x7c0 [ 43.962942] tty_release_struct+0x3c/0x50 [ 43.962949] tty_release+0xaa3/0xd60 [ 43.962959] ? tty_release_struct+0x50/0x50 [ 43.962965] __fput+0x275/0x7a0 [ 43.962973] ____fput+0x16/0x20 [ 43.962980] task_work_run+0x114/0x190 [ 43.962989] do_exit+0xa1a/0x2cd0 [ 43.963003] ? mm_update_next_owner+0x5d0/0x5d0 [ 43.963012] ? up_read+0x1a/0x40 [ 43.963017] ? __do_page_fault+0x358/0xb80 [ 43.963025] do_group_exit+0x111/0x330 [ 43.963032] SyS_exit_group+0x1d/0x20 [ 43.963038] ? do_group_exit+0x330/0x330 [ 43.963044] do_syscall_64+0x1e8/0x640 [ 43.963051] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 43.963060] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 43.963064] RIP: 0033:0x43ff38 [ 43.963068] RSP: 002b:00007ffe90b1e3f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 43.963074] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 43.963078] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 43.963083] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 43.963086] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 43.963090] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 43.964578] Kernel Offset: disabled [ 44.586962] Rebooting in 86400 seconds..