[....] Starting enhanced syslogd: rsyslogd[ 12.941780] audit: type=1400 audit(1516803105.804:5): avc: denied { syslog } for pid=3499 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: [ 19.115743] audit: type=1400 audit(1516803111.978:6): avc: denied { map } for pid=3640 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 '10.128.15.196' (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 [ 33.583325] audit: type=1400 audit(1516803126.446:7): avc: denied { map } for pid=3656 comm="syzkaller613609" path="/root/syzkaller613609157" 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 [ 33.834200] ================================================================== [ 33.841608] BUG: KASAN: use-after-free in __wake_up_common+0x670/0x780 [ 33.848254] Read of size 8 at addr ffff8801d0146c60 by task syzkaller613609/3873 [ 33.855751] [ 33.857351] CPU: 0 PID: 3873 Comm: syzkaller613609 Not tainted 4.15.0-rc9+ #187 [ 33.864763] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.874083] Call Trace: [ 33.876641] dump_stack+0x194/0x257 [ 33.880240] ? arch_local_irq_restore+0x53/0x53 [ 33.884879] ? show_regs_print_info+0x18/0x18 [ 33.889348] ? rcu_segcblist_first_pend_cb+0x90/0x90 [ 33.894422] ? __wake_up_common+0x670/0x780 [ 33.898714] print_address_description+0x73/0x250 [ 33.903526] ? __wake_up_common+0x670/0x780 [ 33.907827] kasan_report+0x25b/0x340 [ 33.911600] __asan_report_load8_noabort+0x14/0x20 [ 33.916497] __wake_up_common+0x670/0x780 [ 33.920618] ? do_wait_intr_irq+0x3e0/0x3e0 [ 33.924918] ? lock_release+0xa40/0xa40 [ 33.928861] ? lock_downgrade+0x980/0x980 [ 33.932989] __wake_up_common_lock+0x1b4/0x310 [ 33.937541] ? locks_remove_file+0x3fa/0x5a0 [ 33.941921] ? __wake_up_common+0x780/0x780 [ 33.946209] ? fcntl_setlk+0x10c0/0x10c0 [ 33.950250] ? fsnotify_first_mark+0x2b0/0x2b0 [ 33.954806] ? eventfd_show_fdinfo+0x90/0x90 [ 33.959184] __wake_up+0xe/0x10 [ 33.962432] eventfd_release+0x4a/0x60 [ 33.966290] __fput+0x327/0x7e0 [ 33.969544] ? fput+0x140/0x140 [ 33.972794] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 33.978647] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.983119] ____fput+0x15/0x20 [ 33.986367] task_work_run+0x199/0x270 [ 33.990227] ? task_work_cancel+0x210/0x210 [ 33.994518] ? _raw_spin_unlock+0x22/0x30 [ 33.998634] ? switch_task_namespaces+0x87/0xc0 [ 34.003277] do_exit+0x9bb/0x1ad0 [ 34.006701] ? find_held_lock+0x35/0x1d0 [ 34.010734] ? mm_update_next_owner+0x930/0x930 [ 34.015375] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 34.020534] ? lock_downgrade+0x980/0x980 [ 34.024653] ? __unqueue_futex+0x1c0/0x290 [ 34.028856] ? lock_release+0xa40/0xa40 [ 34.032801] ? fault_in_user_writeable+0x90/0x90 [ 34.037530] ? do_raw_spin_trylock+0x190/0x190 [ 34.042083] ? futex_wake+0x680/0x680 [ 34.045858] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 34.050932] ? futex_wait+0x6a9/0x9a0 [ 34.054714] ? check_noncircular+0x20/0x20 [ 34.058921] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 34.063995] ? futex_wake+0x2ca/0x680 [ 34.067774] ? find_held_lock+0x35/0x1d0 [ 34.071813] ? get_signal+0x7ae/0x16c0 [ 34.075668] ? lock_downgrade+0x980/0x980 [ 34.079794] do_group_exit+0x149/0x400 [ 34.083652] ? do_raw_spin_trylock+0x190/0x190 [ 34.088201] ? SyS_exit+0x30/0x30 [ 34.091625] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.096091] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.101080] get_signal+0x73f/0x16c0 [ 34.104779] ? ptrace_notify+0x130/0x130 [ 34.108811] ? lock_release+0xa40/0xa40 [ 34.112771] ? mutex_unlock+0xd/0x10 [ 34.116454] ? vhost_net_ioctl+0x2af/0x1910 [ 34.120758] do_signal+0x90/0x1eb0 [ 34.124269] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 34.130124] ? rcu_note_context_switch+0x710/0x710 [ 34.135023] ? setup_sigcontext+0x7d0/0x7d0 [ 34.139318] ? __might_sleep+0x95/0x190 [ 34.143262] ? _cond_resched+0x14/0x30 [ 34.147122] ? selinux_file_ioctl+0x444/0x690 [ 34.151586] ? __fget_light+0x297/0x380 [ 34.155533] ? selinux_capable+0x40/0x40 [ 34.159566] ? handle_mm_fault+0x410/0x8d0 [ 34.163767] ? down_read_trylock+0xdb/0x170 [ 34.168060] ? __do_page_fault+0x32d/0xc90 [ 34.172269] ? exit_to_usermode_loop+0x8c/0x310 [ 34.176913] exit_to_usermode_loop+0x214/0x310 [ 34.181465] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 34.186970] ? compat_SyS_ioctl+0x77/0x2a30 [ 34.191264] ? do_fast_syscall_32+0x156/0xf9d [ 34.195732] do_fast_syscall_32+0xbfd/0xf9d [ 34.200034] ? do_int80_syscall_32+0x9d0/0x9d0 [ 34.204592] ? syscall_return_slowpath+0x2ad/0x550 [ 34.209494] ? prepare_exit_to_usermode+0x340/0x340 [ 34.214484] ? sysret32_from_system_call+0x5/0x3b [ 34.219300] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 34.224117] entry_SYSENTER_compat+0x54/0x63 [ 34.228501] RIP: 0023:0xf7ffac79 [ 34.231835] RSP: 002b:00000000f7fd51ec EFLAGS: 00000296 ORIG_RAX: 00000000000000f0 [ 34.239512] RAX: fffffffffffffe00 RBX: 00000000080faff4 RCX: 0000000000000000 [ 34.246751] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000080faff4 [ 34.253993] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 [ 34.261233] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 34.268471] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 34.275728] [ 34.277326] Allocated by task 3852: [ 34.280922] save_stack+0x43/0xd0 [ 34.284342] kasan_kmalloc+0xad/0xe0 [ 34.288021] __kmalloc_node+0x47/0x70 [ 34.291795] kvmalloc_node+0x64/0xd0 [ 34.295478] vhost_net_open+0x27/0x670 [ 34.299333] misc_open+0x382/0x500 [ 34.302843] chrdev_open+0x257/0x730 [ 34.306526] do_dentry_open+0x667/0xd40 [ 34.310470] vfs_open+0x107/0x220 [ 34.313891] path_openat+0x1151/0x3530 [ 34.317745] do_filp_open+0x25b/0x3b0 [ 34.321513] do_sys_open+0x502/0x6d0 [ 34.325195] compat_SyS_openat+0x2d/0x40 [ 34.329231] do_fast_syscall_32+0x3ee/0xf9d [ 34.333522] entry_SYSENTER_compat+0x54/0x63 [ 34.337895] [ 34.339491] Freed by task 3873: [ 34.342738] save_stack+0x43/0xd0 [ 34.346159] kasan_slab_free+0x71/0xc0 [ 34.350014] kfree+0xd6/0x260 [ 34.353095] kvfree+0x36/0x60 [ 34.356167] vhost_net_release+0x159/0x190 [ 34.360370] __fput+0x327/0x7e0 [ 34.363616] ____fput+0x15/0x20 [ 34.366866] task_work_run+0x199/0x270 [ 34.370722] do_exit+0x9bb/0x1ad0 [ 34.374141] do_group_exit+0x149/0x400 [ 34.377997] get_signal+0x73f/0x16c0 [ 34.381678] do_signal+0x90/0x1eb0 [ 34.385184] exit_to_usermode_loop+0x214/0x310 [ 34.389734] do_fast_syscall_32+0xbfd/0xf9d [ 34.394025] entry_SYSENTER_compat+0x54/0x63 [ 34.398400] [ 34.399998] The buggy address belongs to the object at ffff8801d0142380 [ 34.399998] which belongs to the cache kmalloc-65536 of size 65536 [ 34.412974] The buggy address is located 18656 bytes inside of [ 34.412974] 65536-byte region [ffff8801d0142380, ffff8801d0152380) [ 34.425160] The buggy address belongs to the page: [ 34.430055] page:ffffea0007405000 count:1 mapcount:0 mapping:ffff8801d0142380 index:0x0 compound_mapcount: 0 [ 34.439992] flags: 0x2fffc0000008100(slab|head) [ 34.444632] raw: 02fffc0000008100 ffff8801d0142380 0000000000000000 0000000100000001 [ 34.452478] raw: ffffea0007404820 ffffea0007405820 ffff8801dac02500 0000000000000000 [ 34.460325] page dumped because: kasan: bad access detected [ 34.466017] [ 34.467614] Memory state around the buggy address: [ 34.472512] ffff8801d0146b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.479839] ffff8801d0146b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.487162] >ffff8801d0146c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.494488] ^ [ 34.501208] ffff8801d0146c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.508535] ffff8801d0146d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.515867] ================================================================== [ 34.523194] Disabling lock debugging due to kernel taint [ 34.528616] Kernel panic - not syncing: panic_on_warn set ... [ 34.528616] [ 34.535944] CPU: 0 PID: 3873 Comm: syzkaller613609 Tainted: G B 4.15.0-rc9+ #187 [ 34.544656] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.553976] Call Trace: [ 34.556535] dump_stack+0x194/0x257 [ 34.560153] ? arch_local_irq_restore+0x53/0x53 [ 34.564788] ? kasan_end_report+0x32/0x50 [ 34.568906] ? lock_downgrade+0x980/0x980 [ 34.573023] ? vsnprintf+0x1ed/0x1900 [ 34.576803] ? __wake_up_common+0x670/0x780 [ 34.581097] panic+0x1e4/0x41c [ 34.584258] ? refcount_error_report+0x214/0x214 [ 34.588983] ? add_taint+0x40/0x50 [ 34.592491] ? add_taint+0x1c/0x50 [ 34.596004] ? __wake_up_common+0x670/0x780 [ 34.600294] kasan_end_report+0x50/0x50 [ 34.604242] kasan_report+0x144/0x340 [ 34.608014] __asan_report_load8_noabort+0x14/0x20 [ 34.612913] __wake_up_common+0x670/0x780 [ 34.617035] ? do_wait_intr_irq+0x3e0/0x3e0 [ 34.621327] ? lock_release+0xa40/0xa40 [ 34.625271] ? lock_downgrade+0x980/0x980 [ 34.629396] __wake_up_common_lock+0x1b4/0x310 [ 34.633949] ? locks_remove_file+0x3fa/0x5a0 [ 34.638326] ? __wake_up_common+0x780/0x780 [ 34.642615] ? fcntl_setlk+0x10c0/0x10c0 [ 34.646646] ? fsnotify_first_mark+0x2b0/0x2b0 [ 34.651204] ? eventfd_show_fdinfo+0x90/0x90 [ 34.655585] __wake_up+0xe/0x10 [ 34.658832] eventfd_release+0x4a/0x60 [ 34.662688] __fput+0x327/0x7e0 [ 34.665937] ? fput+0x140/0x140 [ 34.669183] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 34.675033] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.679503] ____fput+0x15/0x20 [ 34.682750] task_work_run+0x199/0x270 [ 34.686605] ? task_work_cancel+0x210/0x210 [ 34.690898] ? _raw_spin_unlock+0x22/0x30 [ 34.696403] ? switch_task_namespaces+0x87/0xc0 [ 34.701043] do_exit+0x9bb/0x1ad0 [ 34.704477] ? find_held_lock+0x35/0x1d0 [ 34.708529] ? mm_update_next_owner+0x930/0x930 [ 34.713175] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 34.718333] ? lock_downgrade+0x980/0x980 [ 34.722457] ? __unqueue_futex+0x1c0/0x290 [ 34.726659] ? lock_release+0xa40/0xa40 [ 34.730598] ? fault_in_user_writeable+0x90/0x90 [ 34.735326] ? do_raw_spin_trylock+0x190/0x190 [ 34.739881] ? futex_wake+0x680/0x680 [ 34.743656] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 34.748726] ? futex_wait+0x6a9/0x9a0 [ 34.752501] ? check_noncircular+0x20/0x20 [ 34.756708] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 34.761777] ? futex_wake+0x2ca/0x680 [ 34.765562] ? find_held_lock+0x35/0x1d0 [ 34.769595] ? get_signal+0x7ae/0x16c0 [ 34.773451] ? lock_downgrade+0x980/0x980 [ 34.777578] do_group_exit+0x149/0x400 [ 34.781435] ? do_raw_spin_trylock+0x190/0x190 [ 34.785984] ? SyS_exit+0x30/0x30 [ 34.789407] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.793870] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.798858] get_signal+0x73f/0x16c0 [ 34.802543] ? ptrace_notify+0x130/0x130 [ 34.806583] ? lock_release+0xa40/0xa40 [ 34.810541] ? mutex_unlock+0xd/0x10 [ 34.814227] ? vhost_net_ioctl+0x2af/0x1910 [ 34.818525] do_signal+0x90/0x1eb0 [ 34.822044] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 34.827922] ? rcu_note_context_switch+0x710/0x710 [ 34.832820] ? setup_sigcontext+0x7d0/0x7d0 [ 34.837106] ? __might_sleep+0x95/0x190 [ 34.841051] ? _cond_resched+0x14/0x30 [ 34.844911] ? selinux_file_ioctl+0x444/0x690 [ 34.849374] ? __fget_light+0x297/0x380 [ 34.853317] ? selinux_capable+0x40/0x40 [ 34.857347] ? handle_mm_fault+0x410/0x8d0 [ 34.861553] ? down_read_trylock+0xdb/0x170 [ 34.865934] ? __do_page_fault+0x32d/0xc90 [ 34.870140] ? exit_to_usermode_loop+0x8c/0x310 [ 34.874779] exit_to_usermode_loop+0x214/0x310 [ 34.879330] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 34.884837] ? compat_SyS_ioctl+0x77/0x2a30 [ 34.889125] ? do_fast_syscall_32+0x156/0xf9d [ 34.893589] do_fast_syscall_32+0xbfd/0xf9d [ 34.897881] ? do_int80_syscall_32+0x9d0/0x9d0 [ 34.902434] ? syscall_return_slowpath+0x2ad/0x550 [ 34.907331] ? prepare_exit_to_usermode+0x340/0x340 [ 34.912316] ? sysret32_from_system_call+0x5/0x3b [ 34.917130] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 34.921941] entry_SYSENTER_compat+0x54/0x63 [ 34.926317] RIP: 0023:0xf7ffac79 [ 34.929646] RSP: 002b:00000000f7fd51ec EFLAGS: 00000296 ORIG_RAX: 00000000000000f0 [ 34.937322] RAX: fffffffffffffe00 RBX: 00000000080faff4 RCX: 0000000000000000 [ 34.944561] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000080faff4 [ 34.951798] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 [ 34.959039] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 34.966285] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 34.973890] Dumping ftrace buffer: [ 34.977397] (ftrace buffer empty) [ 34.981078] Kernel Offset: disabled [ 34.984672] Rebooting in 86400 seconds..