[....] Starting enhanced syslogd: rsyslogd[ 13.541060] audit: type=1400 audit(1516781579.550:5): 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 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: [ 18.447804] audit: type=1400 audit(1516781584.457:6): 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 '10.128.15.218' (ECDSA) to the list of known hosts. [ 130.823547] audit: type=1400 audit(1516781696.833:7): avc: denied { map } for pid=3659 comm="syzkaller191933" path="/root/syzkaller191933174" 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 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 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 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 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 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 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 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 executing program executing program executing program executing program executing program executing program [ 132.107308] ================================================================== [ 132.114701] BUG: KASAN: use-after-free in __lock_acquire+0x3d4d/0x3e00 [ 132.121342] Read of size 8 at addr ffff8801d00e6820 by task syzkaller191933/4232 [ 132.128837] [ 132.130436] CPU: 0 PID: 4232 Comm: syzkaller191933 Not tainted 4.15.0-rc9+ #187 [ 132.137848] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 132.147169] Call Trace: [ 132.149735] dump_stack+0x194/0x257 [ 132.153329] ? arch_local_irq_restore+0x53/0x53 [ 132.157963] ? show_regs_print_info+0x18/0x18 [ 132.162436] ? check_noncircular+0x20/0x20 [ 132.166639] ? __lock_acquire+0x3d4d/0x3e00 [ 132.170933] print_address_description+0x73/0x250 [ 132.175746] ? __lock_acquire+0x3d4d/0x3e00 [ 132.180044] kasan_report+0x25b/0x340 [ 132.183816] __asan_report_load8_noabort+0x14/0x20 [ 132.188711] __lock_acquire+0x3d4d/0x3e00 [ 132.192828] ? check_noncircular+0x20/0x20 [ 132.197035] ? remove_wait_queue+0x81/0x350 [ 132.201326] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 132.206483] ? lock_downgrade+0x980/0x980 [ 132.210601] ? __schedule+0x2060/0x2060 [ 132.214558] ? find_held_lock+0x35/0x1d0 [ 132.218589] ? wait_for_completion+0xe0/0x770 [ 132.223062] ? lock_downgrade+0x980/0x980 [ 132.227189] ? lock_release+0xa40/0xa40 [ 132.231133] ? usleep_range+0x190/0x190 [ 132.235077] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 132.240932] ? kasan_slab_free+0x71/0xc0 [ 132.244962] ? do_raw_spin_trylock+0x190/0x190 [ 132.249516] ? _raw_spin_unlock_irq+0x27/0x70 [ 132.253980] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 132.258961] ? trace_hardirqs_on+0xd/0x10 [ 132.263077] ? _raw_spin_unlock_irq+0x27/0x70 [ 132.267541] ? wait_for_completion+0xe0/0x770 [ 132.272005] ? wait_for_completion_interruptible+0x7e0/0x7e0 [ 132.277773] ? __lockdep_init_map+0xe4/0x650 [ 132.282154] ? llist_add_batch+0xf3/0x180 [ 132.286271] lock_acquire+0x1d5/0x580 [ 132.290043] ? lock_acquire+0x1d5/0x580 [ 132.293989] ? remove_wait_queue+0x81/0x350 [ 132.298290] ? wake_up_process+0x10/0x20 [ 132.302325] ? lock_release+0xa40/0xa40 [ 132.306284] ? vhost_work_queue+0xc0/0xc0 [ 132.310404] ? vhost_poll_stop+0x90/0x90 [ 132.314439] ? wait_for_completion+0x770/0x770 [ 132.319004] _raw_spin_lock_irqsave+0x96/0xc0 [ 132.323469] ? remove_wait_queue+0x81/0x350 [ 132.327760] remove_wait_queue+0x81/0x350 [ 132.331881] ? add_wait_queue+0x290/0x290 [ 132.336001] ? vhost_poll_flush+0x3f/0x60 [ 132.340125] ? vhost_net_flush+0x209/0x2a0 [ 132.344329] vhost_dev_stop+0x15c/0x2a0 [ 132.348271] ? vhost_net_compat_ioctl+0x30/0x30 [ 132.352908] vhost_net_release+0x6e/0x190 [ 132.357036] __fput+0x327/0x7e0 [ 132.360287] ? fput+0x140/0x140 [ 132.363544] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 132.369400] ? _raw_spin_unlock_irq+0x27/0x70 [ 132.373874] ____fput+0x15/0x20 [ 132.377137] task_work_run+0x199/0x270 [ 132.381002] ? task_work_cancel+0x210/0x210 [ 132.385294] ? _raw_spin_unlock+0x22/0x30 [ 132.389423] ? switch_task_namespaces+0x87/0xc0 [ 132.394063] do_exit+0x9bb/0x1ad0 [ 132.397487] ? find_held_lock+0x35/0x1d0 [ 132.401521] ? mm_update_next_owner+0x930/0x930 [ 132.406162] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 132.411329] ? lock_downgrade+0x980/0x980 [ 132.415448] ? __unqueue_futex+0x1c0/0x290 [ 132.419655] ? lock_release+0xa40/0xa40 [ 132.423597] ? fault_in_user_writeable+0x90/0x90 [ 132.428325] ? do_raw_spin_trylock+0x190/0x190 [ 132.432885] ? futex_wake+0x680/0x680 [ 132.436655] ? __init_waitqueue_head+0x97/0x140 [ 132.441296] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 132.446396] ? futex_wait+0x6a9/0x9a0 [ 132.450170] ? check_noncircular+0x20/0x20 [ 132.454392] ? hash_futex+0x15/0x210 [ 132.458083] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 132.463156] ? futex_wake+0x2ca/0x680 [ 132.466928] ? find_held_lock+0x35/0x1d0 [ 132.470961] ? get_signal+0x7ae/0x16c0 [ 132.474820] ? lock_downgrade+0x980/0x980 [ 132.478938] do_group_exit+0x149/0x400 [ 132.482809] ? do_raw_spin_trylock+0x190/0x190 [ 132.487362] ? SyS_exit+0x30/0x30 [ 132.490800] ? _raw_spin_unlock_irq+0x27/0x70 [ 132.495269] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 132.500267] get_signal+0x73f/0x16c0 [ 132.503956] ? ptrace_notify+0x130/0x130 [ 132.507987] ? putname+0xee/0x130 [ 132.511409] ? save_stack+0xa3/0xd0 [ 132.515005] ? save_stack+0x43/0xd0 [ 132.518599] ? kasan_slab_free+0x71/0xc0 [ 132.522626] ? kmem_cache_free+0x83/0x2a0 [ 132.526742] ? putname+0xee/0x130 [ 132.530164] ? do_sys_open+0x31b/0x6d0 [ 132.534019] ? compat_SyS_openat+0x2d/0x40 [ 132.538224] ? do_fast_syscall_32+0x3ee/0xf9d [ 132.542689] ? entry_SYSENTER_compat+0x54/0x63 [ 132.547243] ? __lock_is_held+0xb6/0x140 [ 132.551277] do_signal+0x90/0x1eb0 [ 132.554797] ? free_obj_work+0x690/0x690 [ 132.558827] ? __fd_install+0x288/0x740 [ 132.562782] ? setup_sigcontext+0x7d0/0x7d0 [ 132.567074] ? may_open_dev+0xe0/0xe0 [ 132.570844] ? rcu_pm_notify+0xc0/0xc0 [ 132.575230] ? putname+0xee/0x130 [ 132.578660] ? putname+0xee/0x130 [ 132.582082] ? rcu_read_lock_sched_held+0x108/0x120 [ 132.587072] ? kmem_cache_free+0x267/0x2a0 [ 132.591288] ? exit_to_usermode_loop+0x8c/0x310 [ 132.595932] exit_to_usermode_loop+0x214/0x310 [ 132.602882] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 132.608404] ? do_fast_syscall_32+0x156/0xf9d [ 132.612879] do_fast_syscall_32+0xbfd/0xf9d [ 132.617183] ? do_int80_syscall_32+0x9d0/0x9d0 [ 132.621758] ? syscall_return_slowpath+0x2ad/0x550 [ 132.626670] ? prepare_exit_to_usermode+0x340/0x340 [ 132.631672] ? sysret32_from_system_call+0x5/0x3b [ 132.636492] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 132.641313] entry_SYSENTER_compat+0x54/0x63 [ 132.645709] RIP: 0023:0xf7f92c79 [ 132.649050] RSP: 002b:00000000f7f8e12c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0 [ 132.656740] RAX: fffffffffffffe00 RBX: 00000000080fafe4 RCX: 0000000000000000 [ 132.663993] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000080fafe4 [ 132.671247] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 [ 132.678499] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 132.685760] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 132.693018] [ 132.694629] Allocated by task 4232: [ 132.698235] save_stack+0x43/0xd0 [ 132.701672] kasan_kmalloc+0xad/0xe0 [ 132.705378] kmem_cache_alloc_trace+0x136/0x750 [ 132.710029] eventfd_file_create.part.3+0x96/0x250 [ 132.714944] SyS_eventfd+0x2c/0x80 [ 132.718483] do_fast_syscall_32+0x3ee/0xf9d [ 132.722793] entry_SYSENTER_compat+0x54/0x63 [ 132.727197] [ 132.728806] Freed by task 4232: [ 132.732058] save_stack+0x43/0xd0 [ 132.735489] kasan_slab_free+0x71/0xc0 [ 132.739358] kfree+0xd6/0x260 [ 132.742437] eventfd_ctx_put+0x26/0x30 [ 132.746299] eventfd_release+0x52/0x60 [ 132.750173] __fput+0x327/0x7e0 [ 132.753457] ____fput+0x15/0x20 [ 132.756712] task_work_run+0x199/0x270 [ 132.760580] do_exit+0x9bb/0x1ad0 [ 132.764021] do_group_exit+0x149/0x400 [ 132.767890] get_signal+0x73f/0x16c0 [ 132.771586] do_signal+0x90/0x1eb0 [ 132.775107] exit_to_usermode_loop+0x214/0x310 [ 132.779674] do_fast_syscall_32+0xbfd/0xf9d [ 132.783970] entry_SYSENTER_compat+0x54/0x63 [ 132.788360] [ 132.789967] The buggy address belongs to the object at ffff8801d00e6800 [ 132.789967] which belongs to the cache kmalloc-96 of size 96 [ 132.802434] The buggy address is located 32 bytes inside of [ 132.802434] 96-byte region [ffff8801d00e6800, ffff8801d00e6860) [ 132.814107] The buggy address belongs to the page: [ 132.819014] page:ffffea0007403980 count:1 mapcount:0 mapping:ffff8801d00e6000 index:0x0 [ 132.827147] flags: 0x2fffc0000000100(slab) [ 132.831370] raw: 02fffc0000000100 ffff8801d00e6000 0000000000000000 0000000100000020 [ 132.839232] raw: ffffea0007297be0 ffffea00072b1fe0 ffff8801dac004c0 0000000000000000 [ 132.847111] page dumped because: kasan: bad access detected [ 132.852806] [ 132.854412] Memory state around the buggy address: [ 132.859326] ffff8801d00e6700: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 132.866673] ffff8801d00e6780: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 132.874018] >ffff8801d00e6800: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 132.881355] ^ [ 132.885746] ffff8801d00e6880: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc [ 132.893080] ffff8801d00e6900: 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc [ 132.900412] ================================================================== [ 132.907744] Disabling lock debugging due to kernel taint [ 132.913172] Kernel panic - not syncing: panic_on_warn set ... [ 132.913172] [ 132.920518] CPU: 0 PID: 4232 Comm: syzkaller191933 Tainted: G B 4.15.0-rc9+ #187 [ 132.929239] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 132.938567] Call Trace: [ 132.941136] dump_stack+0x194/0x257 [ 132.944759] ? arch_local_irq_restore+0x53/0x53 [ 132.949419] ? kasan_end_report+0x32/0x50 [ 132.953558] ? lock_downgrade+0x980/0x980 [ 132.957694] ? vsnprintf+0x1ed/0x1900 [ 132.961468] ? __lock_acquire+0x3ca0/0x3e00 [ 132.965773] panic+0x1e4/0x41c [ 132.968943] ? refcount_error_report+0x214/0x214 [ 132.973680] ? add_taint+0x40/0x50 [ 132.977202] ? add_taint+0x1c/0x50 [ 132.980716] ? __lock_acquire+0x3d4d/0x3e00 [ 132.985937] kasan_end_report+0x50/0x50 [ 132.989889] kasan_report+0x144/0x340 [ 132.993670] __asan_report_load8_noabort+0x14/0x20 [ 132.998576] __lock_acquire+0x3d4d/0x3e00 [ 133.002711] ? check_noncircular+0x20/0x20 [ 133.006929] ? remove_wait_queue+0x81/0x350 [ 133.011240] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 133.016412] ? lock_downgrade+0x980/0x980 [ 133.020540] ? __schedule+0x2060/0x2060 [ 133.024494] ? find_held_lock+0x35/0x1d0 [ 133.028531] ? wait_for_completion+0xe0/0x770 [ 133.033001] ? lock_downgrade+0x980/0x980 [ 133.037128] ? lock_release+0xa40/0xa40 [ 133.041074] ? usleep_range+0x190/0x190 [ 133.045028] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 133.050905] ? kasan_slab_free+0x71/0xc0 [ 133.054949] ? do_raw_spin_trylock+0x190/0x190 [ 133.059518] ? _raw_spin_unlock_irq+0x27/0x70 [ 133.063988] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 133.068982] ? trace_hardirqs_on+0xd/0x10 [ 133.073107] ? _raw_spin_unlock_irq+0x27/0x70 [ 133.077577] ? wait_for_completion+0xe0/0x770 [ 133.082055] ? wait_for_completion_interruptible+0x7e0/0x7e0 [ 133.087948] ? __lockdep_init_map+0xe4/0x650 [ 133.092337] ? llist_add_batch+0xf3/0x180 [ 133.096474] lock_acquire+0x1d5/0x580 [ 133.100250] ? lock_acquire+0x1d5/0x580 [ 133.104199] ? remove_wait_queue+0x81/0x350 [ 133.108508] ? wake_up_process+0x10/0x20 [ 133.112570] ? lock_release+0xa40/0xa40 [ 133.116520] ? vhost_work_queue+0xc0/0xc0 [ 133.120646] ? vhost_poll_stop+0x90/0x90 [ 133.124698] ? wait_for_completion+0x770/0x770 [ 133.129255] _raw_spin_lock_irqsave+0x96/0xc0 [ 133.133725] ? remove_wait_queue+0x81/0x350 [ 133.138029] remove_wait_queue+0x81/0x350 [ 133.142159] ? add_wait_queue+0x290/0x290 [ 133.146284] ? vhost_poll_flush+0x3f/0x60 [ 133.150415] ? vhost_net_flush+0x209/0x2a0 [ 133.154635] vhost_dev_stop+0x15c/0x2a0 [ 133.158585] ? vhost_net_compat_ioctl+0x30/0x30 [ 133.163229] vhost_net_release+0x6e/0x190 [ 133.167355] __fput+0x327/0x7e0 [ 133.170611] ? fput+0x140/0x140 [ 133.173867] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 133.179725] ? _raw_spin_unlock_irq+0x27/0x70 [ 133.184197] ____fput+0x15/0x20 [ 133.187452] task_work_run+0x199/0x270 [ 133.191318] ? task_work_cancel+0x210/0x210 [ 133.195613] ? _raw_spin_unlock+0x22/0x30 [ 133.199744] ? switch_task_namespaces+0x87/0xc0 [ 133.204388] do_exit+0x9bb/0x1ad0 [ 133.207814] ? find_held_lock+0x35/0x1d0 [ 133.211852] ? mm_update_next_owner+0x930/0x930 [ 133.216497] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 133.221662] ? lock_downgrade+0x980/0x980 [ 133.225783] ? __unqueue_futex+0x1c0/0x290 [ 133.229993] ? lock_release+0xa40/0xa40 [ 133.233957] ? fault_in_user_writeable+0x90/0x90 [ 133.238694] ? do_raw_spin_trylock+0x190/0x190 [ 133.243260] ? futex_wake+0x680/0x680 [ 133.247044] ? __init_waitqueue_head+0x97/0x140 [ 133.251701] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 133.256782] ? futex_wait+0x6a9/0x9a0 [ 133.260557] ? check_noncircular+0x20/0x20 [ 133.264777] ? hash_futex+0x15/0x210 [ 133.268469] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 133.273544] ? futex_wake+0x2ca/0x680 [ 133.277320] ? find_held_lock+0x35/0x1d0 [ 133.281368] ? get_signal+0x7ae/0x16c0 [ 133.285230] ? lock_downgrade+0x980/0x980 [ 133.289353] do_group_exit+0x149/0x400 [ 133.293217] ? do_raw_spin_trylock+0x190/0x190 [ 133.297771] ? SyS_exit+0x30/0x30 [ 133.301200] ? _raw_spin_unlock_irq+0x27/0x70 [ 133.305670] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 133.310659] get_signal+0x73f/0x16c0 [ 133.314348] ? ptrace_notify+0x130/0x130 [ 133.318385] ? putname+0xee/0x130 [ 133.321810] ? save_stack+0xa3/0xd0 [ 133.325423] ? save_stack+0x43/0xd0 [ 133.329025] ? kasan_slab_free+0x71/0xc0 [ 133.333062] ? kmem_cache_free+0x83/0x2a0 [ 133.337194] ? putname+0xee/0x130 [ 133.340629] ? do_sys_open+0x31b/0x6d0 [ 133.344488] ? compat_SyS_openat+0x2d/0x40 [ 133.348708] ? do_fast_syscall_32+0x3ee/0xf9d [ 133.353177] ? entry_SYSENTER_compat+0x54/0x63 [ 133.357739] ? __lock_is_held+0xb6/0x140 [ 133.361794] do_signal+0x90/0x1eb0 [ 133.365485] ? free_obj_work+0x690/0x690 [ 133.369517] ? __fd_install+0x288/0x740 [ 133.373468] ? setup_sigcontext+0x7d0/0x7d0 [ 133.377774] ? may_open_dev+0xe0/0xe0 [ 133.381560] ? rcu_pm_notify+0xc0/0xc0 [ 133.385428] ? putname+0xee/0x130 [ 133.388857] ? putname+0xee/0x130 [ 133.392288] ? rcu_read_lock_sched_held+0x108/0x120 [ 133.397284] ? kmem_cache_free+0x267/0x2a0 [ 133.401502] ? exit_to_usermode_loop+0x8c/0x310 [ 133.406855] exit_to_usermode_loop+0x214/0x310 [ 133.411420] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 133.416938] ? do_fast_syscall_32+0x156/0xf9d [ 133.421414] do_fast_syscall_32+0xbfd/0xf9d [ 133.425711] ? do_int80_syscall_32+0x9d0/0x9d0 [ 133.430269] ? syscall_return_slowpath+0x2ad/0x550 [ 133.435180] ? prepare_exit_to_usermode+0x340/0x340 [ 133.440186] ? sysret32_from_system_call+0x5/0x3b [ 133.445006] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 133.449835] entry_SYSENTER_compat+0x54/0x63 [ 133.455354] RIP: 0023:0xf7f92c79 [ 133.460315] RSP: 002b:00000000f7f8e12c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0 [ 133.469825] RAX: fffffffffffffe00 RBX: 00000000080fafe4 RCX: 0000000000000000 [ 133.477071] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000080fafe4 [ 133.484315] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 [ 133.491568] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 133.498815] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 133.506520] Dumping ftrace buffer: [ 133.510031] (ftrace buffer empty) [ 133.513713] Kernel Offset: disabled [ 133.517310] Rebooting in 86400 seconds..