[....] Starting enhanced syslogd: rsyslogd[ 16.185817] audit: type=1400 audit(1517304786.032:5): avc: denied { syslog } for pid=3994 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 file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?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: [ 18.294177] audit: type=1400 audit(1517304788.140:6): avc: denied { map } for pid=4133 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 '10.128.0.50' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program [ 24.572457] audit: type=1400 audit(1517304794.419:7): avc: denied { map } for pid=4147 comm="syzkaller481518" path="/root/syzkaller481518014" 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 executing program [ 24.763296] ================================================================== [ 24.770730] BUG: KASAN: use-after-free in __wake_up_common+0x670/0x780 [ 24.777383] Read of size 8 at addr ffff8801d8d21008 by task syzkaller481518/4230 [ 24.784902] [ 24.786521] CPU: 1 PID: 4230 Comm: syzkaller481518 Not tainted 4.15.0+ #196 [ 24.793610] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.802949] Call Trace: [ 24.805514] dump_stack+0x194/0x257 [ 24.809131] ? arch_local_irq_restore+0x53/0x53 [ 24.813780] ? show_regs_print_info+0x18/0x18 [ 24.818258] ? __wake_up_common+0x670/0x780 [ 24.822555] print_address_description+0x73/0x250 [ 24.827380] ? __wake_up_common+0x670/0x780 [ 24.831692] kasan_report+0x25b/0x340 [ 24.835488] __asan_report_load8_noabort+0x14/0x20 [ 24.840405] __wake_up_common+0x670/0x780 [ 24.844537] ? do_wait_intr_irq+0x3e0/0x3e0 [ 24.848833] ? lock_release+0xa40/0xa40 [ 24.852784] ? __dentry_kill+0x487/0x6d0 [ 24.856833] __wake_up_common_lock+0x1b4/0x310 [ 24.861389] ? locks_remove_file+0x3fa/0x5a0 [ 24.865773] ? __wake_up_common+0x780/0x780 [ 24.870066] ? fcntl_setlk+0x10c0/0x10c0 [ 24.874113] ? fsnotify_first_mark+0x2b0/0x2b0 [ 24.878673] ? eventfd_show_fdinfo+0x90/0x90 [ 24.883056] __wake_up+0xe/0x10 [ 24.886307] eventfd_release+0x4a/0x60 [ 24.890168] __fput+0x327/0x7e0 [ 24.893432] ? fput+0x140/0x140 [ 24.896686] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 24.902549] ? _raw_spin_unlock_irq+0x27/0x70 [ 24.907051] ____fput+0x15/0x20 [ 24.910315] task_work_run+0x199/0x270 [ 24.914757] ? task_work_cancel+0x210/0x210 [ 24.919062] ? _raw_spin_unlock+0x22/0x30 [ 24.923196] ? switch_task_namespaces+0x87/0xc0 [ 24.927857] do_exit+0x9bb/0x1ad0 [ 24.931294] ? find_held_lock+0x35/0x1d0 [ 24.935335] ? mm_update_next_owner+0x930/0x930 [ 24.939990] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 24.945162] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 24.949915] ? retint_kernel+0x10/0x10 [ 24.953793] ? futex_wait+0x468/0x9a0 [ 24.957582] ? __sanitizer_cov_trace_pc+0x20/0x50 [ 24.962417] ? perf_trace_lock_acquire+0xe3/0x980 [ 24.967234] ? futex_wait+0x6a9/0x9a0 [ 24.971034] ? perf_trace_lock+0x900/0x900 [ 24.975253] ? check_noncircular+0x20/0x20 [ 24.979468] ? wake_up_q+0x8a/0xe0 [ 24.982992] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 24.988081] ? futex_wake+0x2ca/0x680 [ 24.991873] ? find_held_lock+0x35/0x1d0 [ 24.995918] ? get_signal+0x7ae/0x16c0 [ 24.999779] ? lock_downgrade+0x980/0x980 [ 25.003929] do_group_exit+0x149/0x400 [ 25.007802] ? do_raw_spin_trylock+0x190/0x190 [ 25.012358] ? SyS_exit+0x30/0x30 [ 25.015791] ? _raw_spin_unlock_irq+0x27/0x70 [ 25.020272] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 25.025266] get_signal+0x73f/0x16c0 [ 25.028963] ? ptrace_notify+0x130/0x130 [ 25.032996] ? kfree+0xf0/0x260 [ 25.036269] ? vhost_net_vq_reset+0x91/0x430 [ 25.040654] ? trace_hardirqs_on+0xd/0x10 [ 25.044781] ? mutex_unlock+0xd/0x10 [ 25.048468] ? vhost_net_ioctl+0x2af/0x1910 [ 25.052781] do_signal+0x90/0x1eb0 [ 25.056299] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.062157] ? free_obj_work+0x690/0x690 [ 25.066201] ? rcu_note_context_switch+0x710/0x710 [ 25.071108] ? setup_sigcontext+0x7d0/0x7d0 [ 25.075405] ? __might_sleep+0x95/0x190 [ 25.079358] ? _cond_resched+0x14/0x30 [ 25.083224] ? selinux_file_ioctl+0x444/0x690 [ 25.087692] ? __fget_light+0x297/0x380 [ 25.091640] ? selinux_capable+0x40/0x40 [ 25.095674] ? putname+0xee/0x130 [ 25.099108] ? kmem_cache_free+0x267/0x2a0 [ 25.103325] ? exit_to_usermode_loop+0x8c/0x310 [ 25.107975] exit_to_usermode_loop+0x214/0x310 [ 25.112535] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 25.118050] ? compat_SyS_ioctl+0x77/0x2a30 [ 25.122347] ? lock_downgrade+0x980/0x980 [ 25.126479] ? do_fast_syscall_32+0x156/0xf9d [ 25.130966] do_fast_syscall_32+0xbfd/0xf9d [ 25.135266] ? do_raw_spin_trylock+0x190/0x190 [ 25.139841] ? do_int80_syscall_32+0x9d0/0x9d0 [ 25.144408] ? syscall_return_slowpath+0x2ad/0x550 [ 25.149312] ? prepare_exit_to_usermode+0x340/0x340 [ 25.154302] ? sysret32_from_system_call+0x5/0x3b [ 25.159122] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.163962] entry_SYSENTER_compat+0x54/0x63 [ 25.168350] RIP: 0023:0xf7fabc79 [ 25.171694] RSP: 002b:00000000f7f651ec EFLAGS: 00000296 ORIG_RAX: 00000000000000f0 [ 25.179384] RAX: fffffffffffffe00 RBX: 00000000080fdf84 RCX: 0000000000000000 [ 25.186626] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000080fdf84 [ 25.193875] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 [ 25.201123] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 25.208365] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 25.215628] [ 25.217229] Allocated by task 4230: [ 25.220832] save_stack+0x43/0xd0 [ 25.224257] kasan_kmalloc+0xad/0xe0 [ 25.227942] __kmalloc_node+0x47/0x70 [ 25.231714] kvmalloc_node+0x64/0xd0 [ 25.235400] vhost_net_open+0x27/0x670 [ 25.239271] misc_open+0x382/0x500 [ 25.242789] chrdev_open+0x257/0x730 [ 25.246475] do_dentry_open+0x667/0xd40 [ 25.250426] vfs_open+0x107/0x220 [ 25.253849] path_openat+0x1151/0x3530 [ 25.257717] do_filp_open+0x25b/0x3b0 [ 25.261499] do_sys_open+0x502/0x6d0 [ 25.265188] compat_SyS_openat+0x2d/0x40 [ 25.269240] do_fast_syscall_32+0x3ee/0xf9d [ 25.273534] entry_SYSENTER_compat+0x54/0x63 [ 25.277910] [ 25.279508] Freed by task 4230: [ 25.282759] save_stack+0x43/0xd0 [ 25.286186] kasan_slab_free+0x71/0xc0 [ 25.290046] kfree+0xd6/0x260 [ 25.293133] kvfree+0x36/0x60 [ 25.296221] vhost_net_release+0x159/0x190 [ 25.300431] __fput+0x327/0x7e0 [ 25.303686] ____fput+0x15/0x20 [ 25.306936] task_work_run+0x199/0x270 [ 25.310799] do_exit+0x9bb/0x1ad0 [ 25.314225] do_group_exit+0x149/0x400 [ 25.318085] get_signal+0x73f/0x16c0 [ 25.321776] do_signal+0x90/0x1eb0 [ 25.325298] exit_to_usermode_loop+0x214/0x310 [ 25.329849] do_fast_syscall_32+0xbfd/0xf9d [ 25.334141] entry_SYSENTER_compat+0x54/0x63 [ 25.338528] [ 25.340135] The buggy address belongs to the object at ffff8801d8d20d80 [ 25.340135] which belongs to the cache kmalloc-65536 of size 65536 [ 25.353110] The buggy address is located 648 bytes inside of [ 25.353110] 65536-byte region [ffff8801d8d20d80, ffff8801d8d30d80) [ 25.365126] The buggy address belongs to the page: [ 25.370031] page:ffffea0007634800 count:1 mapcount:0 mapping:ffff8801d8d20d80 index:0x0 compound_mapcount: 0 [ 25.379981] flags: 0x2fffc0000008100(slab|head) [ 25.384637] raw: 02fffc0000008100 ffff8801d8d20d80 0000000000000000 0000000100000001 [ 25.392507] raw: ffffea0006b49820 ffffea0007621820 ffff8801db002500 0000000000000000 [ 25.400364] page dumped because: kasan: bad access detected [ 25.406046] [ 25.407644] Memory state around the buggy address: [ 25.412542] ffff8801d8d20f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.419871] ffff8801d8d20f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.427203] >ffff8801d8d21000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.434529] ^ [ 25.438127] ffff8801d8d21080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.445462] ffff8801d8d21100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.452800] ================================================================== [ 25.460128] Disabling lock debugging due to kernel taint [ 25.465546] Kernel panic - not syncing: panic_on_warn set ... [ 25.465546] [ 25.472877] CPU: 1 PID: 4230 Comm: syzkaller481518 Tainted: G B 4.15.0+ #196 [ 25.481244] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.490570] Call Trace: [ 25.493131] dump_stack+0x194/0x257 [ 25.496731] ? arch_local_irq_restore+0x53/0x53 [ 25.501369] ? kasan_end_report+0x32/0x50 [ 25.505495] ? lock_downgrade+0x980/0x980 [ 25.509622] ? vsnprintf+0x1ed/0x1900 [ 25.513395] ? __wake_up_common+0x670/0x780 [ 25.517687] panic+0x1e4/0x41c [ 25.520850] ? refcount_error_report+0x214/0x214 [ 25.525579] ? add_taint+0x40/0x50 [ 25.529087] ? add_taint+0x1c/0x50 [ 25.532601] ? __wake_up_common+0x670/0x780 [ 25.536893] kasan_end_report+0x50/0x50 [ 25.540839] kasan_report+0x144/0x340 [ 25.544615] __asan_report_load8_noabort+0x14/0x20 [ 25.549519] __wake_up_common+0x670/0x780 [ 25.553642] ? do_wait_intr_irq+0x3e0/0x3e0 [ 25.557937] ? lock_release+0xa40/0xa40 [ 25.561887] ? __dentry_kill+0x487/0x6d0 [ 25.565926] __wake_up_common_lock+0x1b4/0x310 [ 25.570478] ? locks_remove_file+0x3fa/0x5a0 [ 25.574861] ? __wake_up_common+0x780/0x780 [ 25.579151] ? fcntl_setlk+0x10c0/0x10c0 [ 25.583193] ? fsnotify_first_mark+0x2b0/0x2b0 [ 25.587746] ? eventfd_show_fdinfo+0x90/0x90 [ 25.592123] __wake_up+0xe/0x10 [ 25.595371] eventfd_release+0x4a/0x60 [ 25.599231] __fput+0x327/0x7e0 [ 25.602488] ? fput+0x140/0x140 [ 25.605740] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.611596] ? _raw_spin_unlock_irq+0x27/0x70 [ 25.616067] ____fput+0x15/0x20 [ 25.619326] task_work_run+0x199/0x270 [ 25.623187] ? task_work_cancel+0x210/0x210 [ 25.627479] ? _raw_spin_unlock+0x22/0x30 [ 25.631599] ? switch_task_namespaces+0x87/0xc0 [ 25.636242] do_exit+0x9bb/0x1ad0 [ 25.639668] ? find_held_lock+0x35/0x1d0 [ 25.643700] ? mm_update_next_owner+0x930/0x930 [ 25.648341] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 25.653504] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 25.658237] ? retint_kernel+0x10/0x10 [ 25.662100] ? futex_wait+0x468/0x9a0 [ 25.665874] ? __sanitizer_cov_trace_pc+0x20/0x50 [ 25.670690] ? perf_trace_lock_acquire+0xe3/0x980 [ 25.675502] ? futex_wait+0x6a9/0x9a0 [ 25.679278] ? perf_trace_lock+0x900/0x900 [ 25.683487] ? check_noncircular+0x20/0x20 [ 25.687782] ? wake_up_q+0x8a/0xe0 [ 25.691302] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 25.696374] ? futex_wake+0x2ca/0x680 [ 25.700154] ? find_held_lock+0x35/0x1d0 [ 25.704192] ? get_signal+0x7ae/0x16c0 [ 25.708050] ? lock_downgrade+0x980/0x980 [ 25.712176] do_group_exit+0x149/0x400 [ 25.716034] ? do_raw_spin_trylock+0x190/0x190 [ 25.720584] ? SyS_exit+0x30/0x30 [ 25.724010] ? _raw_spin_unlock_irq+0x27/0x70 [ 25.728475] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 25.733467] get_signal+0x73f/0x16c0 [ 25.737156] ? ptrace_notify+0x130/0x130 [ 25.741188] ? kfree+0xf0/0x260 [ 25.744440] ? vhost_net_vq_reset+0x91/0x430 [ 25.748823] ? trace_hardirqs_on+0xd/0x10 [ 25.752945] ? mutex_unlock+0xd/0x10 [ 25.756628] ? vhost_net_ioctl+0x2af/0x1910 [ 25.760927] do_signal+0x90/0x1eb0 [ 25.764440] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.770302] ? free_obj_work+0x690/0x690 [ 25.774334] ? rcu_note_context_switch+0x710/0x710 [ 25.779233] ? setup_sigcontext+0x7d0/0x7d0 [ 25.783523] ? __might_sleep+0x95/0x190 [ 25.787467] ? _cond_resched+0x14/0x30 [ 25.791327] ? selinux_file_ioctl+0x444/0x690 [ 25.795792] ? __fget_light+0x297/0x380 [ 25.799735] ? selinux_capable+0x40/0x40 [ 25.803765] ? putname+0xee/0x130 [ 25.807188] ? kmem_cache_free+0x267/0x2a0 [ 25.811399] ? exit_to_usermode_loop+0x8c/0x310 [ 25.816041] exit_to_usermode_loop+0x214/0x310 [ 25.820594] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 25.826102] ? compat_SyS_ioctl+0x77/0x2a30 [ 25.830393] ? lock_downgrade+0x980/0x980 [ 25.834512] ? do_fast_syscall_32+0x156/0xf9d [ 25.838981] do_fast_syscall_32+0xbfd/0xf9d [ 25.843287] ? do_raw_spin_trylock+0x190/0x190 [ 25.847840] ? do_int80_syscall_32+0x9d0/0x9d0 [ 25.852399] ? syscall_return_slowpath+0x2ad/0x550 [ 25.857297] ? prepare_exit_to_usermode+0x340/0x340 [ 25.862297] ? sysret32_from_system_call+0x5/0x3b [ 25.867113] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.871929] entry_SYSENTER_compat+0x54/0x63 [ 25.876307] RIP: 0023:0xf7fabc79 [ 25.879640] RSP: 002b:00000000f7f651ec EFLAGS: 00000296 ORIG_RAX: 00000000000000f0 [ 25.887320] RAX: fffffffffffffe00 RBX: 00000000080fdf84 RCX: 0000000000000000 [ 25.894559] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000080fdf84 [ 25.901799] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 [ 25.909040] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 25.916277] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 25.923896] Dumping ftrace buffer: [ 25.927406] (ftrace buffer empty) [ 25.931087] Kernel Offset: disabled [ 25.934686] Rebooting in 86400 seconds..