[....] Starting enhanced syslogd: rsyslogd[ 12.076399] audit: type=1400 audit(1516486370.288:5): avc: denied { syslog } for pid=3502 comm="rsyslogd" capability=34 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=capability2 permissive=1 [?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 19.716091] audit: type=1400 audit(1516486377.927:6): avc: denied { map } for pid=3642 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 '10.128.15.212' (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 executing program executing program executing program [ 25.998854] audit: type=1400 audit(1516486384.210:7): avc: denied { map } for pid=3656 comm="syzkaller194205" path="/root/syzkaller194205851" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 executing program executing program executing program executing program executing program executing program executing program [ 26.103194] ================================================================== [ 26.110621] BUG: KASAN: use-after-free in __wake_up_common+0x670/0x780 [ 26.117262] Read of size 8 at addr ffff8801bcf80f08 by task syzkaller194205/3724 [ 26.124774] [ 26.126383] CPU: 0 PID: 3724 Comm: syzkaller194205 Not tainted 4.15.0-rc8+ #270 [ 26.133804] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.143143] Call Trace: [ 26.145709] dump_stack+0x194/0x257 [ 26.149321] ? arch_local_irq_restore+0x53/0x53 [ 26.153962] ? show_regs_print_info+0x18/0x18 [ 26.158432] ? rcu_segcblist_first_pend_cb+0x90/0x90 [ 26.163512] ? __wake_up_common+0x670/0x780 [ 26.167810] print_address_description+0x73/0x250 [ 26.172624] ? __wake_up_common+0x670/0x780 [ 26.176919] kasan_report+0x25b/0x340 [ 26.180696] __asan_report_load8_noabort+0x14/0x20 [ 26.185597] __wake_up_common+0x670/0x780 [ 26.189733] ? do_wait_intr_irq+0x3e0/0x3e0 [ 26.194030] ? lock_release+0xa40/0xa40 [ 26.197978] ? lock_downgrade+0x980/0x980 [ 26.202100] ? check_noncircular+0x20/0x20 [ 26.206315] __wake_up_common_lock+0x1b4/0x310 [ 26.210871] ? locks_remove_file+0x3fa/0x5a0 [ 26.215253] ? __wake_up_common+0x780/0x780 [ 26.219554] ? fcntl_setlk+0x10c0/0x10c0 [ 26.223607] ? fsnotify_first_mark+0x2b0/0x2b0 [ 26.228163] ? eventfd_show_fdinfo+0x90/0x90 [ 26.232542] __wake_up+0xe/0x10 [ 26.235797] eventfd_release+0x4a/0x60 [ 26.239658] __fput+0x327/0x7e0 [ 26.242926] ? fput+0x140/0x140 [ 26.246184] ? _raw_spin_unlock_irq+0x27/0x70 [ 26.250671] ____fput+0x15/0x20 [ 26.253927] task_work_run+0x199/0x270 [ 26.257799] ? task_work_cancel+0x210/0x210 [ 26.262095] ? _raw_spin_unlock+0x22/0x30 [ 26.266215] ? switch_task_namespaces+0x87/0xc0 [ 26.270862] do_exit+0x9bb/0x1ad0 [ 26.274291] ? mm_update_next_owner+0x930/0x930 [ 26.278945] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 26.284121] ? __might_sleep+0x95/0x190 [ 26.288084] ? _cond_resched+0x14/0x30 [ 26.291950] ? futex_wait_queue_me+0x527/0x7e0 [ 26.296514] ? refill_pi_state_cache.part.5+0x2f0/0x2f0 [ 26.301857] ? get_futex_value_locked+0xc3/0xf0 [ 26.306514] ? futex_wait_setup+0x22e/0x3d0 [ 26.310817] ? futex_wake+0x680/0x680 [ 26.314593] ? check_noncircular+0x20/0x20 [ 26.318800] ? rcutorture_record_progress+0x10/0x10 [ 26.323792] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 26.328869] ? futex_wait+0x6a9/0x9a0 [ 26.332654] ? find_held_lock+0x35/0x1d0 [ 26.336704] ? get_signal+0x7ae/0x16c0 [ 26.340575] ? lock_downgrade+0x980/0x980 [ 26.344714] do_group_exit+0x149/0x400 [ 26.348574] ? do_raw_spin_trylock+0x190/0x190 [ 26.353126] ? SyS_exit+0x30/0x30 [ 26.356564] ? _raw_spin_unlock_irq+0x27/0x70 [ 26.361036] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 26.366054] get_signal+0x73f/0x16c0 [ 26.369760] ? ptrace_notify+0x130/0x130 [ 26.373809] ? exit_robust_list+0x240/0x240 [ 26.378105] ? lockdep_init_map+0x9/0x10 [ 26.382140] ? debug_mutex_init+0x2d/0x60 [ 26.386266] ? check_noncircular+0x20/0x20 [ 26.390473] ? SyS_membarrier+0x600/0x600 [ 26.394610] ? kmem_cache_alloc+0x466/0x760 [ 26.398907] ? __raw_spin_lock_init+0x1c/0x100 [ 26.403466] do_signal+0x90/0x1eb0 [ 26.406989] ? setup_sigcontext+0x7d0/0x7d0 [ 26.411289] ? __fd_install+0x25f/0x740 [ 26.415239] ? lock_downgrade+0x980/0x980 [ 26.419368] ? __lock_is_held+0xb6/0x140 [ 26.423412] ? exit_to_usermode_loop+0x8c/0x310 [ 26.428062] exit_to_usermode_loop+0x214/0x310 [ 26.432618] ? compat_SyS_epoll_pwait+0x4f0/0x4f0 [ 26.437434] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 26.442956] syscall_return_slowpath+0x490/0x550 [ 26.447688] ? prepare_exit_to_usermode+0x340/0x340 [ 26.452682] ? entry_SYSCALL_64_fastpath+0x73/0xa0 [ 26.457586] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 26.462588] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.467323] entry_SYSCALL_64_fastpath+0x9e/0xa0 [ 26.472051] RIP: 0033:0x449ac9 [ 26.475226] RSP: 002b:00007f0696bfbda8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 26.482909] RAX: 0000000000000000 RBX: 00000000006dbc24 RCX: 0000000000449ac9 [ 26.490163] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000006dbc24 [ 26.497409] RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000 [ 26.504654] R10: 0000000000000000 R11: 0000000000000246 R12: 6f68762f7665642f [ 26.511896] R13: 006563696d2f7475 R14: 706e692f7665642f R15: 0000000000000008 [ 26.519154] [ 26.520753] Allocated by task 3724: [ 26.524360] save_stack+0x43/0xd0 [ 26.527782] kasan_kmalloc+0xad/0xe0 [ 26.531465] __kmalloc_node+0x47/0x70 [ 26.535237] kvmalloc_node+0x64/0xd0 [ 26.538923] vhost_net_open+0x27/0x670 [ 26.542782] misc_open+0x382/0x500 [ 26.546291] chrdev_open+0x257/0x730 [ 26.549974] do_dentry_open+0x667/0xd40 [ 26.553917] vfs_open+0x107/0x220 [ 26.557339] path_openat+0x1151/0x3530 [ 26.561195] do_filp_open+0x25b/0x3b0 [ 26.564966] do_sys_open+0x502/0x6d0 [ 26.568648] SyS_openat+0x30/0x40 [ 26.572082] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 26.576808] [ 26.578405] Freed by task 3724: [ 26.581667] save_stack+0x43/0xd0 [ 26.585091] kasan_slab_free+0x71/0xc0 [ 26.588964] kfree+0xd6/0x260 [ 26.592042] kvfree+0x36/0x60 [ 26.595122] vhost_net_release+0x159/0x190 [ 26.599327] __fput+0x327/0x7e0 [ 26.602578] ____fput+0x15/0x20 [ 26.605840] task_work_run+0x199/0x270 [ 26.609710] do_exit+0x9bb/0x1ad0 [ 26.613133] do_group_exit+0x149/0x400 [ 26.616991] get_signal+0x73f/0x16c0 [ 26.620677] do_signal+0x90/0x1eb0 [ 26.624192] exit_to_usermode_loop+0x214/0x310 [ 26.628760] syscall_return_slowpath+0x490/0x550 [ 26.633497] entry_SYSCALL_64_fastpath+0x9e/0xa0 [ 26.638219] [ 26.639819] The buggy address belongs to the object at ffff8801bcf80c80 [ 26.639819] which belongs to the cache kmalloc-65536 of size 65536 [ 26.652794] The buggy address is located 648 bytes inside of [ 26.652794] 65536-byte region [ffff8801bcf80c80, ffff8801bcf90c80) [ 26.664824] The buggy address belongs to the page: [ 26.669725] page:ffffea0006f3e000 count:1 mapcount:0 mapping:ffff8801bcf80c80 index:0x0 compound_mapcount: 0 [ 26.679679] flags: 0x2fffc0000008100(slab|head) [ 26.684333] raw: 02fffc0000008100 ffff8801bcf80c80 0000000000000000 0000000100000001 [ 26.692186] raw: ffffea0006f26820 ffffea0006f3e820 ffff8801dac02500 0000000000000000 [ 26.700045] page dumped because: kasan: bad access detected [ 26.705723] [ 26.707333] Memory state around the buggy address: [ 26.712232] ffff8801bcf80e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.719562] ffff8801bcf80e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.726891] >ffff8801bcf80f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.734220] ^ [ 26.737818] ffff8801bcf80f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.745149] ffff8801bcf81000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.752481] ================================================================== [ 26.759810] Disabling lock debugging due to kernel taint [ 26.765228] Kernel panic - not syncing: panic_on_warn set ... [ 26.765228] [ 26.772569] CPU: 0 PID: 3724 Comm: syzkaller194205 Tainted: G B 4.15.0-rc8+ #270 [ 26.781380] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.790722] Call Trace: [ 26.793302] dump_stack+0x194/0x257 [ 26.796911] ? arch_local_irq_restore+0x53/0x53 [ 26.801550] ? kasan_end_report+0x32/0x50 [ 26.805669] ? lock_downgrade+0x980/0x980 [ 26.809787] ? vsnprintf+0x1ed/0x1900 [ 26.813570] ? __wake_up_common+0x610/0x780 [ 26.817864] panic+0x1e4/0x41c [ 26.821036] ? refcount_error_report+0x214/0x214 [ 26.825763] ? add_taint+0x40/0x50 [ 26.829271] ? add_taint+0x1c/0x50 [ 26.832792] ? __wake_up_common+0x670/0x780 [ 26.837084] kasan_end_report+0x50/0x50 [ 26.841028] kasan_report+0x144/0x340 [ 26.844803] __asan_report_load8_noabort+0x14/0x20 [ 26.849703] __wake_up_common+0x670/0x780 [ 26.853826] ? do_wait_intr_irq+0x3e0/0x3e0 [ 26.858116] ? lock_release+0xa40/0xa40 [ 26.862059] ? lock_downgrade+0x980/0x980 [ 26.866176] ? check_noncircular+0x20/0x20 [ 26.870393] __wake_up_common_lock+0x1b4/0x310 [ 26.874957] ? locks_remove_file+0x3fa/0x5a0 [ 26.879347] ? __wake_up_common+0x780/0x780 [ 26.883645] ? fcntl_setlk+0x10c0/0x10c0 [ 26.887686] ? fsnotify_first_mark+0x2b0/0x2b0 [ 26.892248] ? eventfd_show_fdinfo+0x90/0x90 [ 26.896627] __wake_up+0xe/0x10 [ 26.899881] eventfd_release+0x4a/0x60 [ 26.903757] __fput+0x327/0x7e0 [ 26.907008] ? fput+0x140/0x140 [ 26.910259] ? _raw_spin_unlock_irq+0x27/0x70 [ 26.914729] ____fput+0x15/0x20 [ 26.917979] task_work_run+0x199/0x270 [ 26.921837] ? task_work_cancel+0x210/0x210 [ 26.926141] ? _raw_spin_unlock+0x22/0x30 [ 26.930274] ? switch_task_namespaces+0x87/0xc0 [ 26.934916] do_exit+0x9bb/0x1ad0 [ 26.938351] ? mm_update_next_owner+0x930/0x930 [ 26.942993] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 26.948153] ? __might_sleep+0x95/0x190 [ 26.952102] ? _cond_resched+0x14/0x30 [ 26.955970] ? futex_wait_queue_me+0x527/0x7e0 [ 26.960525] ? refill_pi_state_cache.part.5+0x2f0/0x2f0 [ 26.965860] ? get_futex_value_locked+0xc3/0xf0 [ 26.970505] ? futex_wait_setup+0x22e/0x3d0 [ 26.974801] ? futex_wake+0x680/0x680 [ 26.978576] ? check_noncircular+0x20/0x20 [ 26.982796] ? rcutorture_record_progress+0x10/0x10 [ 26.987786] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 26.992863] ? futex_wait+0x6a9/0x9a0 [ 26.996641] ? find_held_lock+0x35/0x1d0 [ 27.000679] ? get_signal+0x7ae/0x16c0 [ 27.004537] ? lock_downgrade+0x980/0x980 [ 27.008663] do_group_exit+0x149/0x400 [ 27.012522] ? do_raw_spin_trylock+0x190/0x190 [ 27.017073] ? SyS_exit+0x30/0x30 [ 27.020497] ? _raw_spin_unlock_irq+0x27/0x70 [ 27.024964] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 27.029968] get_signal+0x73f/0x16c0 [ 27.033658] ? ptrace_notify+0x130/0x130 [ 27.037700] ? exit_robust_list+0x240/0x240 [ 27.042002] ? lockdep_init_map+0x9/0x10 [ 27.046034] ? debug_mutex_init+0x2d/0x60 [ 27.050165] ? check_noncircular+0x20/0x20 [ 27.054369] ? SyS_membarrier+0x600/0x600 [ 27.058487] ? kmem_cache_alloc+0x466/0x760 [ 27.062781] ? __raw_spin_lock_init+0x1c/0x100 [ 27.067340] do_signal+0x90/0x1eb0 [ 27.070857] ? setup_sigcontext+0x7d0/0x7d0 [ 27.075153] ? __fd_install+0x25f/0x740 [ 27.079098] ? lock_downgrade+0x980/0x980 [ 27.083220] ? __lock_is_held+0xb6/0x140 [ 27.087259] ? exit_to_usermode_loop+0x8c/0x310 [ 27.091900] exit_to_usermode_loop+0x214/0x310 [ 27.096455] ? compat_SyS_epoll_pwait+0x4f0/0x4f0 [ 27.101275] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 27.106789] syscall_return_slowpath+0x490/0x550 [ 27.111518] ? prepare_exit_to_usermode+0x340/0x340 [ 27.116517] ? entry_SYSCALL_64_fastpath+0x73/0xa0 [ 27.121516] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 27.126602] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 27.131506] entry_SYSCALL_64_fastpath+0x9e/0xa0 [ 27.136242] RIP: 0033:0x449ac9 [ 27.139416] RSP: 002b:00007f0696bfbda8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 27.147095] RAX: 0000000000000000 RBX: 00000000006dbc24 RCX: 0000000000449ac9 [ 27.154346] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000006dbc24 [ 27.161586] RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000 [ 27.168827] R10: 0000000000000000 R11: 0000000000000246 R12: 6f68762f7665642f [ 27.176078] R13: 006563696d2f7475 R14: 706e692f7665642f R15: 0000000000000008 [ 27.183686] Dumping ftrace buffer: [ 27.187215] (ftrace buffer empty) [ 27.190900] Kernel Offset: disabled [ 27.194512] Rebooting in 86400 seconds..