[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [ 86.372949][ T27] audit: type=1400 audit(1584340892.344:38): avc: denied { watch } for pid=10201 comm="restorecond" path="/etc/selinux/restorecond.conf" dev="sda1" ino=2232 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 86.661508][ T27] audit: type=1800 audit(1584340892.654:39): pid=10114 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=2432 res=0 [ 86.683272][ T27] audit: type=1800 audit(1584340892.654:40): pid=10114 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=2423 res=0 Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 89.330755][ T27] audit: type=1400 audit(1584340895.324:41): avc: denied { map } for pid=10294 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 '10.128.0.244' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 111.348286][ T27] audit: type=1400 audit(1584340917.334:42): avc: denied { map } for pid=10306 comm="syz-executor308" path="/root/syz-executor308486900" dev="sda1" ino=1426 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 111.432350][T10320] ================================================================== [ 111.432409][T10320] BUG: KASAN: use-after-free in con_shutdown+0x7f/0x90 [ 111.432419][T10320] Write of size 8 at addr ffff8880a2aab108 by task syz-executor308/10320 [ 111.432423][T10320] [ 111.432436][T10320] CPU: 1 PID: 10320 Comm: syz-executor308 Not tainted 5.6.0-rc5-syzkaller #0 [ 111.432444][T10320] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 111.432448][T10320] Call Trace: [ 111.432465][T10320] dump_stack+0x188/0x20d [ 111.432478][T10320] ? con_shutdown+0x7f/0x90 [ 111.432492][T10320] ? con_shutdown+0x7f/0x90 [ 111.432512][T10320] print_address_description.constprop.0.cold+0xd3/0x315 [ 111.432523][T10320] ? con_shutdown+0x7f/0x90 [ 111.432536][T10320] ? con_shutdown+0x7f/0x90 [ 111.432549][T10320] __kasan_report.cold+0x1a/0x32 [ 111.432566][T10320] ? con_shutdown+0x7f/0x90 [ 111.432584][T10320] kasan_report+0xe/0x20 [ 111.432597][T10320] con_shutdown+0x7f/0x90 [ 111.432607][T10320] ? update_region+0x140/0x140 [ 111.432618][T10320] release_tty+0xca/0x450 [ 111.432633][T10320] tty_release_struct+0x37/0x50 [ 111.432646][T10320] tty_release+0xbc7/0xe90 [ 111.432674][T10320] ? do_tty_hangup+0x30/0x30 [ 111.432685][T10320] __fput+0x2da/0x850 [ 111.432710][T10320] task_work_run+0x13f/0x1b0 [ 111.432734][T10320] do_exit+0xb34/0x2dd0 [ 111.432763][T10320] ? mm_update_next_owner+0x7a0/0x7a0 [ 111.432777][T10320] ? up_read+0x1ab/0x750 [ 111.432791][T10320] ? mark_held_locks+0x9f/0xe0 [ 111.432804][T10320] ? down_read_non_owner+0x470/0x470 [ 111.432821][T10320] ? handle_mm_fault+0x491/0xa10 [ 111.432843][T10320] do_group_exit+0x125/0x340 [ 111.432858][T10320] __x64_sys_exit_group+0x3a/0x50 [ 111.432870][T10320] do_syscall_64+0xf6/0x7d0 [ 111.432886][T10320] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 111.432895][T10320] RIP: 0033:0x43ff38 [ 111.432906][T10320] Code: 00 00 be 3c 00 00 00 eb 19 66 0f 1f 84 00 00 00 00 00 48 89 d7 89 f0 0f 05 48 3d 00 f0 ff ff 77 21 f4 48 89 d7 44 89 c0 0f 05 <48> 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 0f 1f 84 00 00 00 [ 111.432912][T10320] RSP: 002b:00007ffeabe4c998 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 111.432922][T10320] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 111.432928][T10320] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 111.432934][T10320] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 111.432940][T10320] R10: 0000000000000064 R11: 0000000000000246 R12: 0000000000000001 [ 111.432946][T10320] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 111.432969][T10320] [ 111.432975][T10320] Allocated by task 10320: [ 111.432985][T10320] save_stack+0x1b/0x80 [ 111.432996][T10320] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 111.433007][T10320] kmem_cache_alloc_trace+0x153/0x7d0 [ 111.433017][T10320] vc_allocate+0x1e2/0x6e0 [ 111.433027][T10320] con_install+0x4f/0x400 [ 111.433038][T10320] tty_init_dev+0xf5/0x460 [ 111.433047][T10320] tty_open+0x47f/0xb30 [ 111.433057][T10320] chrdev_open+0x219/0x5c0 [ 111.433068][T10320] do_dentry_open+0x4a2/0x1250 [ 111.433080][T10320] path_openat+0x122a/0x32b0 [ 111.433090][T10320] do_filp_open+0x192/0x260 [ 111.433101][T10320] do_sys_openat2+0x54c/0x740 [ 111.433112][T10320] do_sys_open+0xc3/0x140 [ 111.433124][T10320] do_syscall_64+0xf6/0x7d0 [ 111.433136][T10320] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 111.433139][T10320] [ 111.433146][T10320] Freed by task 10318: [ 111.433157][T10320] save_stack+0x1b/0x80 [ 111.433169][T10320] __kasan_slab_free+0xf7/0x140 [ 111.433179][T10320] kfree+0x109/0x2b0 [ 111.433196][T10320] vt_disallocate_all+0x293/0x3b0 [ 111.433206][T10320] vt_ioctl+0xb79/0x2470 [ 111.433215][T10320] tty_ioctl+0xedd/0x1440 [ 111.433226][T10320] ksys_ioctl+0x11a/0x180 [ 111.433237][T10320] __x64_sys_ioctl+0x6f/0xb0 [ 111.433248][T10320] do_syscall_64+0xf6/0x7d0 [ 111.433258][T10320] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 111.433262][T10320] [ 111.433270][T10320] The buggy address belongs to the object at ffff8880a2aab000 [ 111.433270][T10320] which belongs to the cache kmalloc-2k of size 2048 [ 111.433280][T10320] The buggy address is located 264 bytes inside of [ 111.433280][T10320] 2048-byte region [ffff8880a2aab000, ffff8880a2aab800) [ 111.433284][T10320] The buggy address belongs to the page: [ 111.433295][T10320] page:ffffea00028aaac0 refcount:1 mapcount:0 mapping:ffff8880aa000e00 index:0x0 [ 111.433305][T10320] flags: 0xfffe0000000200(slab) [ 111.433321][T10320] raw: 00fffe0000000200 ffffea00029f3f88 ffffea0002707048 ffff8880aa000e00 [ 111.433334][T10320] raw: 0000000000000000 ffff8880a2aab000 0000000100000001 0000000000000000 [ 111.433339][T10320] page dumped because: kasan: bad access detected [ 111.433342][T10320] [ 111.433346][T10320] Memory state around the buggy address: [ 111.433355][T10320] ffff8880a2aab000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 111.433365][T10320] ffff8880a2aab080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 111.433374][T10320] >ffff8880a2aab100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 111.433378][T10320] ^ [ 111.433388][T10320] ffff8880a2aab180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 111.433397][T10320] ffff8880a2aab200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 111.433401][T10320] ================================================================== [ 111.433405][T10320] Disabling lock debugging due to kernel taint [ 111.433431][T10320] Kernel panic - not syncing: panic_on_warn set ... [ 111.433444][T10320] CPU: 1 PID: 10320 Comm: syz-executor308 Tainted: G B 5.6.0-rc5-syzkaller #0 [ 111.433450][T10320] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 111.433453][T10320] Call Trace: [ 111.433466][T10320] dump_stack+0x188/0x20d [ 111.433481][T10320] panic+0x2e3/0x75c [ 111.433492][T10320] ? add_taint.cold+0x16/0x16 [ 111.433500][T10320] ? retint_kernel+0x2b/0x2b [ 111.433518][T10320] ? trace_hardirqs_on+0x55/0x220 [ 111.433537][T10320] ? con_shutdown+0x7f/0x90 [ 111.433547][T10320] end_report+0x43/0x49 [ 111.433557][T10320] ? con_shutdown+0x7f/0x90 [ 111.433568][T10320] __kasan_report.cold+0xd/0x32 [ 111.433581][T10320] ? con_shutdown+0x7f/0x90 [ 111.433592][T10320] kasan_report+0xe/0x20 [ 111.433602][T10320] con_shutdown+0x7f/0x90 [ 111.433612][T10320] ? update_region+0x140/0x140 [ 111.433621][T10320] release_tty+0xca/0x450 [ 111.433634][T10320] tty_release_struct+0x37/0x50 [ 111.433644][T10320] tty_release+0xbc7/0xe90 [ 111.433661][T10320] ? do_tty_hangup+0x30/0x30 [ 111.433670][T10320] __fput+0x2da/0x850 [ 111.433687][T10320] task_work_run+0x13f/0x1b0 [ 111.433704][T10320] do_exit+0xb34/0x2dd0 [ 111.433724][T10320] ? mm_update_next_owner+0x7a0/0x7a0 [ 111.433736][T10320] ? up_read+0x1ab/0x750 [ 111.433746][T10320] ? mark_held_locks+0x9f/0xe0 [ 111.433759][T10320] ? down_read_non_owner+0x470/0x470 [ 111.433774][T10320] ? handle_mm_fault+0x491/0xa10 [ 111.433787][T10320] do_group_exit+0x125/0x340 [ 111.433800][T10320] __x64_sys_exit_group+0x3a/0x50 [ 111.433812][T10320] do_syscall_64+0xf6/0x7d0 [ 111.433825][T10320] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 111.433839][T10320] RIP: 0033:0x43ff38 [ 111.433851][T10320] Code: 00 00 be 3c 00 00 00 eb 19 66 0f 1f 84 00 00 00 00 00 48 89 d7 89 f0 0f 05 48 3d 00 f0 ff ff 77 21 f4 48 89 d7 44 89 c0 0f 05 <48> 3d 00 f0 ff ff 76 e0 f7 d8 64 41 89 01 eb d8 0f 1f 84 00 00 00 [ 111.433857][T10320] RSP: 002b:00007ffeabe4c998 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 111.433866][T10320] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043ff38 [ 111.433872][T10320] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 111.433878][T10320] RBP: 00000000004bf950 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 111.433885][T10320] R10: 0000000000000064 R11: 0000000000000246 R12: 0000000000000001 [ 111.433891][T10320] R13: 00000000006d2180 R14: 0000000000000000 R15: 0000000000000000 [ 111.435163][T10320] Kernel Offset: disabled [ 112.188590][T10320] Rebooting in 86400 seconds..