[....] Starting enhanced syslogd: rsyslogd[ 13.429385] audit: type=1400 audit(1516903060.097:5): avc: denied { syslog } for pid=3500 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: [ 19.726636] audit: type=1400 audit(1516903066.394:6): 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 '10.128.0.13' (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 [ 25.955147] audit: type=1400 audit(1516903072.622:7): avc: denied { map } for pid=3654 comm="syzkaller251701" path="/root/syzkaller251701631" 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 [ 26.011394] ================================================================== [ 26.018838] BUG: KASAN: use-after-free in __wake_up_common+0x670/0x780 [ 26.025501] Read of size 8 at addr ffff8801c1944ee0 by task syzkaller251701/3692 [ 26.033024] [ 26.034659] CPU: 0 PID: 3692 Comm: syzkaller251701 Not tainted 4.15.0-rc9+ #279 [ 26.042085] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.051427] Call Trace: [ 26.053994] dump_stack+0x194/0x257 [ 26.057612] ? arch_local_irq_restore+0x53/0x53 [ 26.062261] ? show_regs_print_info+0x18/0x18 [ 26.066739] ? rcu_segcblist_first_pend_cb+0x90/0x90 [ 26.071820] ? __wake_up_common+0x670/0x780 [ 26.076140] print_address_description+0x73/0x250 [ 26.080973] ? __wake_up_common+0x670/0x780 [ 26.085279] kasan_report+0x25b/0x340 [ 26.089069] __asan_report_load8_noabort+0x14/0x20 [ 26.093971] __wake_up_common+0x670/0x780 [ 26.098100] ? do_wait_intr_irq+0x3e0/0x3e0 [ 26.102398] ? lock_release+0xa40/0xa40 [ 26.106347] ? lock_downgrade+0x980/0x980 [ 26.110505] __wake_up_common_lock+0x1b4/0x310 [ 26.115074] ? locks_remove_file+0x3fa/0x5a0 [ 26.119461] ? __wake_up_common+0x780/0x780 [ 26.123764] ? fcntl_setlk+0x10c0/0x10c0 [ 26.127817] ? fsnotify_first_mark+0x2b0/0x2b0 [ 26.132383] ? eventfd_show_fdinfo+0x90/0x90 [ 26.136764] __wake_up+0xe/0x10 [ 26.140024] eventfd_release+0x4a/0x60 [ 26.143891] __fput+0x327/0x7e0 [ 26.147155] ? fput+0x140/0x140 [ 26.150410] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 26.156268] ? _raw_spin_unlock_irq+0x27/0x70 [ 26.160743] ____fput+0x15/0x20 [ 26.163997] task_work_run+0x199/0x270 [ 26.167880] ? task_work_cancel+0x210/0x210 [ 26.172186] ? _raw_spin_unlock+0x22/0x30 [ 26.176309] ? switch_task_namespaces+0x87/0xc0 [ 26.180957] do_exit+0x9bb/0x1ad0 [ 26.184393] ? mm_update_next_owner+0x930/0x930 [ 26.189051] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 26.194222] ? __might_sleep+0x95/0x190 [ 26.198174] ? find_held_lock+0x35/0x1d0 [ 26.202226] ? futex_wait+0x402/0x9a0 [ 26.206011] ? lock_downgrade+0x980/0x980 [ 26.210143] ? __unqueue_futex+0x1c0/0x290 [ 26.214353] ? lock_release+0xa40/0xa40 [ 26.218319] ? fault_in_user_writeable+0x90/0x90 [ 26.223066] ? do_raw_spin_trylock+0x190/0x190 [ 26.227636] ? futex_wake+0x680/0x680 [ 26.231421] ? check_noncircular+0x20/0x20 [ 26.235636] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 26.240725] ? futex_wait+0x6a9/0x9a0 [ 26.244525] ? find_held_lock+0x35/0x1d0 [ 26.248587] ? get_signal+0x7ae/0x16c0 [ 26.252451] ? lock_downgrade+0x980/0x980 [ 26.256584] do_group_exit+0x149/0x400 [ 26.260456] ? do_raw_spin_trylock+0x190/0x190 [ 26.265027] ? SyS_exit+0x30/0x30 [ 26.268464] ? _raw_spin_unlock_irq+0x27/0x70 [ 26.272943] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 26.277940] get_signal+0x73f/0x16c0 [ 26.281654] ? ptrace_notify+0x130/0x130 [ 26.285695] ? exit_robust_list+0x240/0x240 [ 26.289991] ? avc_has_extended_perms+0x7fa/0x12c0 [ 26.294897] ? find_held_lock+0x35/0x1d0 [ 26.298938] ? vhost_net_stop_vq+0xf0/0xf0 [ 26.303168] ? avc_ss_reset+0x110/0x110 [ 26.307130] ? lock_downgrade+0x980/0x980 [ 26.311269] do_signal+0x90/0x1eb0 [ 26.314799] ? __lock_is_held+0xb6/0x140 [ 26.318855] ? setup_sigcontext+0x7d0/0x7d0 [ 26.323186] ? up_read+0x1a/0x40 [ 26.326531] ? rcu_note_context_switch+0x710/0x710 [ 26.331447] ? exit_to_usermode_loop+0x8c/0x310 [ 26.336099] exit_to_usermode_loop+0x214/0x310 [ 26.340663] ? ioctl_preallocate+0x2b0/0x2b0 [ 26.345061] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 26.350582] ? selinux_capable+0x40/0x40 [ 26.354628] syscall_return_slowpath+0x490/0x550 [ 26.359363] ? prepare_exit_to_usermode+0x340/0x340 [ 26.364372] ? entry_SYSCALL_64_fastpath+0x73/0xa0 [ 26.369288] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 26.374296] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.379053] entry_SYSCALL_64_fastpath+0x9e/0xa0 [ 26.383788] RIP: 0033:0x445d89 [ 26.386958] RSP: 002b:00007f862767bda8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 26.394652] RAX: fffffffffffffe00 RBX: 00000000006dbc3c RCX: 0000000000445d89 [ 26.401909] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000006dbc3c [ 26.409164] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 26.416416] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc38 [ 26.423670] R13: 6f68762f7665642f R14: 00007f862767c9c0 R15: 0000000000000007 [ 26.430933] [ 26.432536] Allocated by task 3680: [ 26.436140] save_stack+0x43/0xd0 [ 26.439585] kasan_kmalloc+0xad/0xe0 [ 26.443283] __kmalloc_node+0x47/0x70 [ 26.447067] kvmalloc_node+0x64/0xd0 [ 26.450756] vhost_net_open+0x27/0x670 [ 26.454632] misc_open+0x382/0x500 [ 26.458148] chrdev_open+0x257/0x730 [ 26.461836] do_dentry_open+0x667/0xd40 [ 26.465794] vfs_open+0x107/0x220 [ 26.469229] path_openat+0x1151/0x3530 [ 26.473110] do_filp_open+0x25b/0x3b0 [ 26.476882] do_sys_open+0x502/0x6d0 [ 26.480569] SyS_openat+0x30/0x40 [ 26.483996] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 26.488726] [ 26.490332] Freed by task 3692: [ 26.493596] save_stack+0x43/0xd0 [ 26.497032] kasan_slab_free+0x71/0xc0 [ 26.500897] kfree+0xd6/0x260 [ 26.503975] kvfree+0x36/0x60 [ 26.507055] vhost_net_release+0x159/0x190 [ 26.511261] __fput+0x327/0x7e0 [ 26.514514] ____fput+0x15/0x20 [ 26.517767] task_work_run+0x199/0x270 [ 26.521625] do_exit+0x9bb/0x1ad0 [ 26.525058] do_group_exit+0x149/0x400 [ 26.528924] get_signal+0x73f/0x16c0 [ 26.532609] do_signal+0x90/0x1eb0 [ 26.536123] exit_to_usermode_loop+0x214/0x310 [ 26.540675] syscall_return_slowpath+0x490/0x550 [ 26.545403] entry_SYSCALL_64_fastpath+0x9e/0xa0 [ 26.550129] [ 26.551738] The buggy address belongs to the object at ffff8801c1940600 [ 26.551738] which belongs to the cache kmalloc-65536 of size 65536 [ 26.564710] The buggy address is located 18656 bytes inside of [ 26.564710] 65536-byte region [ffff8801c1940600, ffff8801c1950600) [ 26.576900] The buggy address belongs to the page: [ 26.581807] page:ffffea0007065000 count:1 mapcount:0 mapping:ffff8801c1940600 index:0x0 compound_mapcount: 0 [ 26.591750] flags: 0x2fffc0000008100(slab|head) [ 26.596399] raw: 02fffc0000008100 ffff8801c1940600 0000000000000000 0000000100000001 [ 26.604258] raw: ffffea0007066020 ffffea00070bf820 ffff8801dac02500 0000000000000000 [ 26.612109] page dumped because: kasan: bad access detected [ 26.617789] [ 26.619391] Memory state around the buggy address: [ 26.624297] ffff8801c1944d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.631638] ffff8801c1944e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.638979] >ffff8801c1944e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.646309] ^ [ 26.653346] ffff8801c1944f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.660682] ffff8801c1944f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 26.668013] ================================================================== [ 26.675350] Disabling lock debugging due to kernel taint [ 26.680769] Kernel panic - not syncing: panic_on_warn set ... [ 26.680769] [ 26.688101] CPU: 0 PID: 3692 Comm: syzkaller251701 Tainted: G B 4.15.0-rc9+ #279 [ 26.696818] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.706143] Call Trace: [ 26.708706] dump_stack+0x194/0x257 [ 26.712332] ? arch_local_irq_restore+0x53/0x53 [ 26.716981] ? kasan_end_report+0x32/0x50 [ 26.721108] ? lock_downgrade+0x980/0x980 [ 26.725235] ? vsnprintf+0x1ed/0x1900 [ 26.729019] ? __wake_up_common+0x670/0x780 [ 26.733325] panic+0x1e4/0x41c [ 26.736495] ? refcount_error_report+0x214/0x214 [ 26.741223] ? add_taint+0x40/0x50 [ 26.744733] ? add_taint+0x1c/0x50 [ 26.748255] ? __wake_up_common+0x670/0x780 [ 26.752557] kasan_end_report+0x50/0x50 [ 26.756510] kasan_report+0x144/0x340 [ 26.760284] __asan_report_load8_noabort+0x14/0x20 [ 26.765187] __wake_up_common+0x670/0x780 [ 26.769308] ? do_wait_intr_irq+0x3e0/0x3e0 [ 26.773608] ? lock_release+0xa40/0xa40 [ 26.777567] ? lock_downgrade+0x980/0x980 [ 26.781691] __wake_up_common_lock+0x1b4/0x310 [ 26.786252] ? locks_remove_file+0x3fa/0x5a0 [ 26.790634] ? __wake_up_common+0x780/0x780 [ 26.794943] ? fcntl_setlk+0x10c0/0x10c0 [ 26.798985] ? fsnotify_first_mark+0x2b0/0x2b0 [ 26.803543] ? eventfd_show_fdinfo+0x90/0x90 [ 26.807928] __wake_up+0xe/0x10 [ 26.811183] eventfd_release+0x4a/0x60 [ 26.815050] __fput+0x327/0x7e0 [ 26.818322] ? fput+0x140/0x140 [ 26.821576] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 26.827433] ? _raw_spin_unlock_irq+0x27/0x70 [ 26.831902] ____fput+0x15/0x20 [ 26.835167] task_work_run+0x199/0x270 [ 26.839034] ? task_work_cancel+0x210/0x210 [ 26.843337] ? _raw_spin_unlock+0x22/0x30 [ 26.847460] ? switch_task_namespaces+0x87/0xc0 [ 26.852112] do_exit+0x9bb/0x1ad0 [ 26.855551] ? mm_update_next_owner+0x930/0x930 [ 26.860202] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 26.865373] ? __might_sleep+0x95/0x190 [ 26.869330] ? find_held_lock+0x35/0x1d0 [ 26.873368] ? futex_wait+0x402/0x9a0 [ 26.877142] ? lock_downgrade+0x980/0x980 [ 26.881264] ? __unqueue_futex+0x1c0/0x290 [ 26.885471] ? lock_release+0xa40/0xa40 [ 26.889417] ? fault_in_user_writeable+0x90/0x90 [ 26.894154] ? do_raw_spin_trylock+0x190/0x190 [ 26.898717] ? futex_wake+0x680/0x680 [ 26.902491] ? check_noncircular+0x20/0x20 [ 26.906700] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 26.911776] ? futex_wait+0x6a9/0x9a0 [ 26.915554] ? find_held_lock+0x35/0x1d0 [ 26.919597] ? get_signal+0x7ae/0x16c0 [ 26.923456] ? lock_downgrade+0x980/0x980 [ 26.927592] do_group_exit+0x149/0x400 [ 26.931458] ? do_raw_spin_trylock+0x190/0x190 [ 26.936034] ? SyS_exit+0x30/0x30 [ 26.939477] ? _raw_spin_unlock_irq+0x27/0x70 [ 26.943945] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 26.948939] get_signal+0x73f/0x16c0 [ 26.952638] ? ptrace_notify+0x130/0x130 [ 26.956674] ? exit_robust_list+0x240/0x240 [ 26.960970] ? avc_has_extended_perms+0x7fa/0x12c0 [ 26.965873] ? find_held_lock+0x35/0x1d0 [ 26.969913] ? vhost_net_stop_vq+0xf0/0xf0 [ 26.974121] ? avc_ss_reset+0x110/0x110 [ 26.978071] ? lock_downgrade+0x980/0x980 [ 26.982197] do_signal+0x90/0x1eb0 [ 26.985713] ? __lock_is_held+0xb6/0x140 [ 26.989748] ? setup_sigcontext+0x7d0/0x7d0 [ 26.994058] ? up_read+0x1a/0x40 [ 26.997398] ? rcu_note_context_switch+0x710/0x710 [ 27.002324] ? exit_to_usermode_loop+0x8c/0x310 [ 27.006968] exit_to_usermode_loop+0x214/0x310 [ 27.011523] ? ioctl_preallocate+0x2b0/0x2b0 [ 27.015904] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 27.021431] ? selinux_capable+0x40/0x40 [ 27.025478] syscall_return_slowpath+0x490/0x550 [ 27.030206] ? prepare_exit_to_usermode+0x340/0x340 [ 27.035195] ? entry_SYSCALL_64_fastpath+0x73/0xa0 [ 27.040096] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 27.045084] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 27.049819] entry_SYSCALL_64_fastpath+0x9e/0xa0 [ 27.054544] RIP: 0033:0x445d89 [ 27.057710] RSP: 002b:00007f862767bda8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 27.065395] RAX: fffffffffffffe00 RBX: 00000000006dbc3c RCX: 0000000000445d89 [ 27.072637] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000006dbc3c [ 27.079878] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 27.087125] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc38 [ 27.094375] R13: 6f68762f7665642f R14: 00007f862767c9c0 R15: 0000000000000007 [ 27.102028] Dumping ftrace buffer: [ 27.105546] (ftrace buffer empty) [ 27.109226] Kernel Offset: disabled [ 27.112839] Rebooting in 86400 seconds..