[....] Starting enhanced syslogd: rsyslogd[ 17.589918] audit: type=1400 audit(1517318106.789:5): avc: denied { syslog } for pid=4015 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 periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] 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: [ 22.613083] audit: type=1400 audit(1517318111.812:6): avc: denied { map } for pid=4156 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 '10.128.0.37' (ECDSA) to the list of known hosts. executing program [ 34.023065] audit: type=1400 audit(1517318123.222:7): avc: denied { map } for pid=4171 comm="syzkaller948031" path="/root/syzkaller948031729" 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 [ 34.056030] ================================================================== [ 34.063482] BUG: KASAN: use-after-free in __wake_up_common+0x670/0x780 [ 34.070123] Read of size 8 at addr ffff8801a9340448 by task syzkaller948031/4171 [ 34.077630] [ 34.079241] CPU: 0 PID: 4171 Comm: syzkaller948031 Not tainted 4.15.0+ #196 [ 34.086311] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.095640] Call Trace: [ 34.098209] dump_stack+0x194/0x257 [ 34.101816] ? arch_local_irq_restore+0x53/0x53 [ 34.106459] ? show_regs_print_info+0x18/0x18 [ 34.110937] ? __wake_up_common+0x670/0x780 [ 34.115241] print_address_description+0x73/0x250 [ 34.120058] ? __wake_up_common+0x670/0x780 [ 34.124352] kasan_report+0x25b/0x340 [ 34.128137] __asan_report_load8_noabort+0x14/0x20 [ 34.133043] __wake_up_common+0x670/0x780 [ 34.137171] ? do_wait_intr_irq+0x3e0/0x3e0 [ 34.141469] ? unwind_get_return_address+0x61/0xa0 [ 34.146375] ? check_noncircular+0x20/0x20 [ 34.150591] __wake_up_common_lock+0x1b4/0x310 [ 34.155152] ? locks_remove_file+0x3fa/0x5a0 [ 34.159537] ? __wake_up_common+0x780/0x780 [ 34.163831] ? fcntl_setlk+0x10c0/0x10c0 [ 34.167876] ? fsnotify_first_mark+0x2b0/0x2b0 [ 34.172439] ? eventfd_show_fdinfo+0x90/0x90 [ 34.176850] __wake_up+0xe/0x10 [ 34.180112] eventfd_release+0x4a/0x60 [ 34.183985] __fput+0x327/0x7e0 [ 34.187250] ? fput+0x140/0x140 [ 34.190508] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.194997] ____fput+0x15/0x20 [ 34.198252] task_work_run+0x199/0x270 [ 34.202116] ? task_work_cancel+0x210/0x210 [ 34.206420] ? _raw_spin_unlock+0x22/0x30 [ 34.210547] ? switch_task_namespaces+0x87/0xc0 [ 34.215199] do_exit+0x9bb/0x1ad0 [ 34.218637] ? mm_update_next_owner+0x930/0x930 [ 34.223287] ? lock_downgrade+0x980/0x980 [ 34.227428] ? lock_release+0xa40/0xa40 [ 34.231376] ? lock_downgrade+0x980/0x980 [ 34.235498] ? check_noncircular+0x20/0x20 [ 34.239720] ? mntput_no_expire+0x15e/0xa90 [ 34.244019] ? _raw_spin_unlock+0x22/0x30 [ 34.248154] ? mnt_get_count+0x150/0x150 [ 34.252203] ? find_held_lock+0x35/0x1d0 [ 34.256252] ? task_work_run+0x16c/0x270 [ 34.260376] ? lock_downgrade+0x980/0x980 [ 34.264503] ? lock_release+0xa40/0xa40 [ 34.268468] ? do_raw_spin_trylock+0x190/0x190 [ 34.273032] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.277524] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.282518] ? trace_hardirqs_on+0xd/0x10 [ 34.286642] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.291112] ? task_work_run+0x1f4/0x270 [ 34.295149] ? task_work_cancel+0x210/0x210 [ 34.299445] ? __close_fd+0x222/0x360 [ 34.303219] ? exit_to_usermode_loop+0x8c/0x310 [ 34.307865] do_group_exit+0x149/0x400 [ 34.311730] ? trace_hardirqs_off+0xd/0x10 [ 34.315938] ? exit_to_usermode_loop+0x198/0x310 [ 34.320669] ? SyS_exit+0x30/0x30 [ 34.324115] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 34.329643] ? do_fast_syscall_32+0x156/0xf9d [ 34.334113] ? do_group_exit+0x400/0x400 [ 34.338157] SyS_exit_group+0x1d/0x20 [ 34.341946] do_fast_syscall_32+0x3ee/0xf9d [ 34.346255] ? do_int80_syscall_32+0x9d0/0x9d0 [ 34.350821] ? kasan_check_read+0x11/0x20 [ 34.354949] ? syscall_return_slowpath+0x550/0x550 [ 34.359857] ? SyS_rt_sigaction+0x94/0x1b0 [ 34.364070] ? SyS_sigprocmask+0x4b0/0x4b0 [ 34.368296] ? SyS_read+0x184/0x220 [ 34.371909] ? sysret32_from_system_call+0x5/0x3b [ 34.376731] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 34.381554] entry_SYSENTER_compat+0x54/0x63 [ 34.385940] RIP: 0023:0xf7ffcc79 [ 34.389276] RSP: 002b:00000000ff99282c EFLAGS: 00000296 ORIG_RAX: 00000000000000fc [ 34.396961] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000080eb298 [ 34.404205] RDX: 0000000000000000 RSI: 00000000080d57f8 RDI: 00000000080eb2a0 [ 34.411451] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 [ 34.418694] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 34.425942] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 34.433209] [ 34.434811] Allocated by task 4171: [ 34.438419] save_stack+0x43/0xd0 [ 34.441847] kasan_kmalloc+0xad/0xe0 [ 34.445537] __kmalloc_node+0x47/0x70 [ 34.449314] kvmalloc_node+0x64/0xd0 [ 34.453004] vhost_net_open+0x27/0x670 [ 34.456867] misc_open+0x382/0x500 [ 34.460382] chrdev_open+0x257/0x730 [ 34.464070] do_dentry_open+0x667/0xd40 [ 34.468015] vfs_open+0x107/0x220 [ 34.471442] path_openat+0x1151/0x3530 [ 34.475302] do_filp_open+0x25b/0x3b0 [ 34.479074] do_sys_open+0x502/0x6d0 [ 34.482760] compat_SyS_openat+0x2d/0x40 [ 34.486793] do_fast_syscall_32+0x3ee/0xf9d [ 34.491090] entry_SYSENTER_compat+0x54/0x63 [ 34.495465] [ 34.497064] Freed by task 4171: [ 34.500330] save_stack+0x43/0xd0 [ 34.503761] kasan_slab_free+0x71/0xc0 [ 34.507627] kfree+0xd6/0x260 [ 34.510712] kvfree+0x36/0x60 [ 34.513799] vhost_net_release+0x159/0x190 [ 34.518014] __fput+0x327/0x7e0 [ 34.521268] ____fput+0x15/0x20 [ 34.524543] task_work_run+0x199/0x270 [ 34.528409] exit_to_usermode_loop+0x296/0x310 [ 34.532970] do_fast_syscall_32+0xbfd/0xf9d [ 34.537354] entry_SYSENTER_compat+0x54/0x63 [ 34.541737] [ 34.543340] The buggy address belongs to the object at ffff8801a93401c0 [ 34.543340] which belongs to the cache kmalloc-65536 of size 65536 [ 34.556332] The buggy address is located 648 bytes inside of [ 34.556332] 65536-byte region [ffff8801a93401c0, ffff8801a93501c0) [ 34.568350] The buggy address belongs to the page: [ 34.573257] page:ffffea0006a4d000 count:1 mapcount:0 mapping:ffff8801a93401c0 index:0x0 compound_mapcount: 0 [ 34.583201] flags: 0x2fffc0000008100(slab|head) [ 34.587848] raw: 02fffc0000008100 ffff8801a93401c0 0000000000000000 0000000100000001 [ 34.595703] raw: ffffea000749d020 ffffea0006a4c820 ffff8801db002500 0000000000000000 [ 34.603553] page dumped because: kasan: bad access detected [ 34.609231] [ 34.610831] Memory state around the buggy address: [ 34.615736] ffff8801a9340300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.623065] ffff8801a9340380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.630393] >ffff8801a9340400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.637725] ^ [ 34.643406] ffff8801a9340480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.650751] ffff8801a9340500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.658105] ================================================================== [ 34.665476] Disabling lock debugging due to kernel taint [ 34.670901] Kernel panic - not syncing: panic_on_warn set ... [ 34.670901] [ 34.678237] CPU: 0 PID: 4171 Comm: syzkaller948031 Tainted: G B 4.15.0+ #196 [ 34.686606] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.695930] Call Trace: [ 34.698498] dump_stack+0x194/0x257 [ 34.702108] ? arch_local_irq_restore+0x53/0x53 [ 34.706752] ? kasan_end_report+0x32/0x50 [ 34.710875] ? lock_downgrade+0x980/0x980 [ 34.714994] ? vsnprintf+0x1ed/0x1900 [ 34.718768] ? __wake_up_common+0x670/0x780 [ 34.723059] panic+0x1e4/0x41c [ 34.726219] ? refcount_error_report+0x214/0x214 [ 34.730948] ? add_taint+0x40/0x50 [ 34.734463] ? add_taint+0x1c/0x50 [ 34.737980] ? __wake_up_common+0x670/0x780 [ 34.742273] kasan_end_report+0x50/0x50 [ 34.746215] kasan_report+0x144/0x340 [ 34.749988] __asan_report_load8_noabort+0x14/0x20 [ 34.754886] __wake_up_common+0x670/0x780 [ 34.759012] ? do_wait_intr_irq+0x3e0/0x3e0 [ 34.763304] ? unwind_get_return_address+0x61/0xa0 [ 34.768205] ? check_noncircular+0x20/0x20 [ 34.772412] __wake_up_common_lock+0x1b4/0x310 [ 34.776972] ? locks_remove_file+0x3fa/0x5a0 [ 34.781350] ? __wake_up_common+0x780/0x780 [ 34.785638] ? fcntl_setlk+0x10c0/0x10c0 [ 34.789677] ? fsnotify_first_mark+0x2b0/0x2b0 [ 34.794229] ? eventfd_show_fdinfo+0x90/0x90 [ 34.798605] __wake_up+0xe/0x10 [ 34.801851] eventfd_release+0x4a/0x60 [ 34.805708] __fput+0x327/0x7e0 [ 34.808966] ? fput+0x140/0x140 [ 34.812218] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.816688] ____fput+0x15/0x20 [ 34.819942] task_work_run+0x199/0x270 [ 34.823808] ? task_work_cancel+0x210/0x210 [ 34.828101] ? _raw_spin_unlock+0x22/0x30 [ 34.832219] ? switch_task_namespaces+0x87/0xc0 [ 34.836860] do_exit+0x9bb/0x1ad0 [ 34.840295] ? mm_update_next_owner+0x930/0x930 [ 34.844934] ? lock_downgrade+0x980/0x980 [ 34.849060] ? lock_release+0xa40/0xa40 [ 34.853004] ? lock_downgrade+0x980/0x980 [ 34.857132] ? check_noncircular+0x20/0x20 [ 34.861341] ? mntput_no_expire+0x15e/0xa90 [ 34.865642] ? _raw_spin_unlock+0x22/0x30 [ 34.869763] ? mnt_get_count+0x150/0x150 [ 34.873794] ? find_held_lock+0x35/0x1d0 [ 34.877828] ? task_work_run+0x16c/0x270 [ 34.881860] ? lock_downgrade+0x980/0x980 [ 34.885977] ? lock_release+0xa40/0xa40 [ 34.889922] ? do_raw_spin_trylock+0x190/0x190 [ 34.894474] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.898942] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.903929] ? trace_hardirqs_on+0xd/0x10 [ 34.908051] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.912516] ? task_work_run+0x1f4/0x270 [ 34.916547] ? task_work_cancel+0x210/0x210 [ 34.920839] ? __close_fd+0x222/0x360 [ 34.924611] ? exit_to_usermode_loop+0x8c/0x310 [ 34.929250] do_group_exit+0x149/0x400 [ 34.933109] ? trace_hardirqs_off+0xd/0x10 [ 34.937313] ? exit_to_usermode_loop+0x198/0x310 [ 34.942037] ? SyS_exit+0x30/0x30 [ 34.945461] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 34.950970] ? do_fast_syscall_32+0x156/0xf9d [ 34.955434] ? do_group_exit+0x400/0x400 [ 34.959474] SyS_exit_group+0x1d/0x20 [ 34.963246] do_fast_syscall_32+0x3ee/0xf9d [ 34.967544] ? do_int80_syscall_32+0x9d0/0x9d0 [ 34.972096] ? kasan_check_read+0x11/0x20 [ 34.976214] ? syscall_return_slowpath+0x550/0x550 [ 34.981117] ? SyS_rt_sigaction+0x94/0x1b0 [ 34.985322] ? SyS_sigprocmask+0x4b0/0x4b0 [ 34.989527] ? SyS_read+0x184/0x220 [ 34.993124] ? sysret32_from_system_call+0x5/0x3b [ 34.997941] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 35.002770] entry_SYSENTER_compat+0x54/0x63 [ 35.007159] RIP: 0023:0xf7ffcc79 [ 35.010492] RSP: 002b:00000000ff99282c EFLAGS: 00000296 ORIG_RAX: 00000000000000fc [ 35.018179] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000080eb298 [ 35.025420] RDX: 0000000000000000 RSI: 00000000080d57f8 RDI: 00000000080eb2a0 [ 35.032659] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 [ 35.039900] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 35.047150] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 35.054786] Dumping ftrace buffer: [ 35.058294] (ftrace buffer empty) [ 35.061976] Kernel Offset: disabled [ 35.065573] Rebooting in 86400 seconds..