INIT: Entering runlevel: 2 [info] Using makefile-style concurrent boot in runlevel 2. [....] Starting enhanced syslogd: rsyslogd[?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 Warning: Permanently added 'ci-upstream-mmots-kasan-gce-7,10.128.15.231' (ECDSA) to the list of known hosts. 2017/09/30 19:18:45 parsed 1 programs 2017/09/30 19:18:45 executed programs: 0 syzkaller login: [ 45.099287] ================================================================== [ 45.100336] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 45.101213] Read of size 8 at addr ffff8801cd6d95a8 by task syz-executor0/3168 [ 45.102172] [ 45.102402] CPU: 0 PID: 3168 Comm: syz-executor0 Not tainted 4.14.0-rc2-mm1+ #11 [ 45.103385] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.104601] Call Trace: [ 45.104957] dump_stack+0x194/0x257 [ 45.105445] ? arch_local_irq_restore+0x53/0x53 [ 45.106064] ? show_regs_print_info+0x65/0x65 [ 45.106660] ? __kernel_text_address+0xd/0x40 [ 45.107257] ? __lock_acquire+0x407b/0x4620 [ 45.107832] print_address_description+0x73/0x250 [ 45.108476] ? __lock_acquire+0x407b/0x4620 [ 45.109050] kasan_report+0x25b/0x340 [ 45.109559] __asan_report_load8_noabort+0x14/0x20 [ 45.110211] __lock_acquire+0x407b/0x4620 [ 45.110763] ? unwind_dump+0x4c0/0x4c0 [ 45.111280] ? __unwind_start+0x169/0x330 [ 45.111831] ? __kernel_text_address+0xd/0x40 [ 45.112427] ? unwind_get_return_address+0x61/0xa0 [ 45.113081] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.113766] ? unwind_get_return_address+0x61/0xa0 [ 45.114419] ? __save_stack_trace+0x61/0xd0 [ 45.114994] ? get_signal+0x73f/0x16d0 [ 45.115514] ? save_stack_trace+0x16/0x20 [ 45.116065] ? __lock_acquire+0x20fd/0x4620 [ 45.116640] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.117328] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.118012] ? save_stack_trace+0x16/0x20 [ 45.118563] ? __lock_acquire+0x20fd/0x4620 [ 45.119136] ? osq_unlock+0x350/0x350 [ 45.121425] ? save_stack_trace+0x16/0x20 [ 45.125535] ? lock_release+0xd70/0xd70 [ 45.129473] ? check_noncircular+0x20/0x20 [ 45.133671] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.139022] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.144190] ? find_held_lock+0x39/0x1d0 [ 45.148221] ? lock_downgrade+0x990/0x990 [ 45.152333] ? check_noncircular+0x20/0x20 [ 45.156531] lock_acquire+0x1d5/0x580 [ 45.160295] ? exit_pi_state_list+0x369/0x7a0 [ 45.164755] ? lock_release+0xd70/0xd70 [ 45.168702] ? do_raw_spin_trylock+0x190/0x190 [ 45.173248] ? find_held_lock+0x39/0x1d0 [ 45.177278] _raw_spin_lock_irq+0x5e/0x80 [ 45.181392] ? exit_pi_state_list+0x369/0x7a0 [ 45.185852] exit_pi_state_list+0x369/0x7a0 [ 45.190144] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 45.196188] ? lock_release+0xd70/0xd70 [ 45.200127] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 45.205974] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 45.211043] ? __might_sleep+0x95/0x190 [ 45.214983] ? __might_fault+0x188/0x1d0 [ 45.219007] ? do_raw_spin_trylock+0x190/0x190 [ 45.223561] mm_release+0x46d/0x590 [ 45.227149] ? do_raw_spin_trylock+0x190/0x190 [ 45.231694] ? mm_access+0x140/0x140 [ 45.235372] ? _raw_spin_unlock_irq+0x27/0x70 [ 45.239830] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 45.244809] ? trace_hardirqs_on+0xd/0x10 [ 45.248920] ? _raw_spin_unlock_irq+0x27/0x70 [ 45.253377] ? acct_collect+0x637/0x800 [ 45.257314] do_exit+0x481/0x1b00 [ 45.260733] ? mm_update_next_owner+0x930/0x930 [ 45.265368] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 45.271216] ? find_held_lock+0x39/0x1d0 [ 45.275243] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 45.280568] ? check_noncircular+0x20/0x20 [ 45.284766] ? fault_in_user_writeable+0x90/0x90 [ 45.289484] ? futex_wake+0x680/0x680 [ 45.293249] ? find_held_lock+0x39/0x1d0 [ 45.297275] ? lock_downgrade+0x990/0x990 [ 45.301386] ? recalc_sigpending_tsk+0x117/0x150 [ 45.306105] ? recalc_sigpending+0x103/0x160 [ 45.310477] ? recalc_sigpending_tsk+0x150/0x150 [ 45.315195] ? get_signal+0x2b2/0x16d0 [ 45.319046] do_group_exit+0x149/0x400 [ 45.322896] ? __lock_is_held+0xbc/0x140 [ 45.326921] ? SyS_exit+0x30/0x30 [ 45.330337] ? _raw_spin_unlock_irq+0x27/0x70 [ 45.334794] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 45.339772] get_signal+0x73f/0x16d0 [ 45.343450] ? ptrace_notify+0x130/0x130 [ 45.347475] ? find_held_lock+0x39/0x1d0 [ 45.351498] ? exit_robust_list+0x240/0x240 [ 45.355780] ? lock_downgrade+0x990/0x990 [ 45.359893] ? lock_downgrade+0x990/0x990 [ 45.364003] do_signal+0x94/0x1ee0 [ 45.367507] ? cpuset_wait_for_hotplug+0x20/0x20 [ 45.372226] ? find_held_lock+0x39/0x1d0 [ 45.376249] ? setup_sigcontext+0x7d0/0x7d0 [ 45.380534] ? lock_downgrade+0x990/0x990 [ 45.384643] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 45.389624] ? lock_release+0xd70/0xd70 [ 45.393561] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 45.399408] ? exit_to_usermode_loop+0x8c/0x310 [ 45.404041] exit_to_usermode_loop+0x214/0x310 [ 45.408588] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 45.414089] ? kasan_check_write+0x14/0x20 [ 45.418287] syscall_return_slowpath+0x42f/0x510 [ 45.423004] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 45.427982] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 45.432875] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 45.437858] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 45.442576] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 45.447292] RIP: 0033:0x4520a9 [ 45.450443] RSP: 002b:00007f873c101cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 45.458113] RAX: fffffffffffffe00 RBX: 0000000000718188 RCX: 00000000004520a9 [ 45.465347] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718188 [ 45.472580] RBP: 0000000000718160 R08: 0000000000000000 R09: 0000000000000000 [ 45.479812] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 45.487045] R13: 00007ffc994bac6f R14: 00007f873c1029c0 R15: 0000000000000004 [ 45.494282] [ 45.495873] Allocated by task 3169: [ 45.499462] save_stack_trace+0x16/0x20 [ 45.503396] save_stack+0x43/0xd0 [ 45.506812] kasan_kmalloc+0xad/0xe0 [ 45.510488] kmem_cache_alloc_trace+0x136/0x750 [ 45.515119] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 45.520184] futex_requeue+0x1887/0x2370 [ 45.524205] do_futex+0x7f5/0x20d0 [ 45.527706] SyS_futex+0x260/0x390 [ 45.531210] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 45.535925] [ 45.537515] Freed by task 3167: [ 45.540757] save_stack_trace+0x16/0x20 [ 45.544691] save_stack+0x43/0xd0 [ 45.548106] kasan_slab_free+0x71/0xc0 [ 45.551953] kfree+0xca/0x250 [ 45.555019] put_pi_state+0x3f4/0x560 [ 45.558780] unqueue_me_pi+0x4a/0xc0 [ 45.562456] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 45.568215] do_futex+0x825/0x20d0 [ 45.571716] SyS_futex+0x260/0x390 [ 45.575217] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 45.579931] [ 45.581532] The buggy address belongs to the object at ffff8801cd6d9580 [ 45.581532] which belongs to the cache kmalloc-256 of size 256 [ 45.594149] The buggy address is located 40 bytes inside of [ 45.594149] 256-byte region [ffff8801cd6d9580, ffff8801cd6d9680) [ 45.605896] The buggy address belongs to the page: [ 45.610787] page:ffffea000735b640 count:1 mapcount:0 mapping:ffff8801cd6d9080 index:0x0 [ 45.618890] flags: 0x200000000000100(slab) [ 45.623097] raw: 0200000000000100 ffff8801cd6d9080 0000000000000000 000000010000000c [ 45.630941] raw: ffffea0007350a20 ffffea0007344020 ffff8801dac007c0 0000000000000000 [ 45.638779] page dumped because: kasan: bad access detected [ 45.644446] [ 45.646035] Memory state around the buggy address: [ 45.650926] ffff8801cd6d9480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 45.658245] ffff8801cd6d9500: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 45.665565] >ffff8801cd6d9580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 45.672884] ^ [ 45.677512] ffff8801cd6d9600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 45.684833] ffff8801cd6d9680: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 45.692152] ================================================================== [ 45.699472] Disabling lock debugging due to kernel taint [ 45.704885] Kernel panic - not syncing: panic_on_warn set ... [ 45.704885] [ 45.712210] CPU: 0 PID: 3168 Comm: syz-executor0 Tainted: G B 4.14.0-rc2-mm1+ #11 [ 45.720926] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.730241] Call Trace: [ 45.732792] dump_stack+0x194/0x257 [ 45.736381] ? arch_local_irq_restore+0x53/0x53 [ 45.741013] ? vprintk_default+0x28/0x30 [ 45.745037] ? __lock_acquire+0x4060/0x4620 [ 45.749325] panic+0x1e4/0x41c [ 45.752479] ? refcount_error_report+0x214/0x214 [ 45.757199] ? __lock_acquire+0x407b/0x4620 [ 45.761483] kasan_end_report+0x50/0x50 [ 45.765420] kasan_report+0x144/0x340 [ 45.769185] __asan_report_load8_noabort+0x14/0x20 [ 45.774075] __lock_acquire+0x407b/0x4620 [ 45.778185] ? unwind_dump+0x4c0/0x4c0 [ 45.782033] ? __unwind_start+0x169/0x330 [ 45.786145] ? __kernel_text_address+0xd/0x40 [ 45.790603] ? unwind_get_return_address+0x61/0xa0 [ 45.795497] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.800649] ? unwind_get_return_address+0x61/0xa0 [ 45.805541] ? __save_stack_trace+0x61/0xd0 [ 45.809828] ? get_signal+0x73f/0x16d0 [ 45.813680] ? save_stack_trace+0x16/0x20 [ 45.817789] ? __lock_acquire+0x20fd/0x4620 [ 45.822075] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.827230] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.832381] ? save_stack_trace+0x16/0x20 [ 45.836490] ? __lock_acquire+0x20fd/0x4620 [ 45.840774] ? osq_unlock+0x350/0x350 [ 45.844536] ? save_stack_trace+0x16/0x20 [ 45.848645] ? lock_release+0xd70/0xd70 [ 45.852581] ? check_noncircular+0x20/0x20 [ 45.856778] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.861931] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.867085] ? find_held_lock+0x39/0x1d0 [ 45.871110] ? lock_downgrade+0x990/0x990 [ 45.875221] ? check_noncircular+0x20/0x20 [ 45.879417] lock_acquire+0x1d5/0x580 [ 45.883180] ? exit_pi_state_list+0x369/0x7a0 [ 45.887640] ? lock_release+0xd70/0xd70 [ 45.891578] ? do_raw_spin_trylock+0x190/0x190 [ 45.896121] ? find_held_lock+0x39/0x1d0 [ 45.900149] _raw_spin_lock_irq+0x5e/0x80 [ 45.904259] ? exit_pi_state_list+0x369/0x7a0 [ 45.908716] exit_pi_state_list+0x369/0x7a0 [ 45.913005] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 45.919025] ? lock_release+0xd70/0xd70 [ 45.922962] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 45.928813] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 45.933879] ? __might_sleep+0x95/0x190 [ 45.937819] ? __might_fault+0x188/0x1d0 [ 45.941846] ? do_raw_spin_trylock+0x190/0x190 [ 45.946391] mm_release+0x46d/0x590 [ 45.949979] ? do_raw_spin_trylock+0x190/0x190 [ 45.954522] ? mm_access+0x140/0x140 [ 45.958199] ? _raw_spin_unlock_irq+0x27/0x70 [ 45.962655] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 45.967633] ? trace_hardirqs_on+0xd/0x10 [ 45.971745] ? _raw_spin_unlock_irq+0x27/0x70 [ 45.976204] ? acct_collect+0x637/0x800 [ 45.980143] do_exit+0x481/0x1b00 [ 45.983559] ? mm_update_next_owner+0x930/0x930 [ 45.988191] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 45.994037] ? find_held_lock+0x39/0x1d0 [ 45.998064] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 46.003392] ? check_noncircular+0x20/0x20 [ 46.007590] ? fault_in_user_writeable+0x90/0x90 [ 46.012307] ? futex_wake+0x680/0x680 [ 46.016071] ? find_held_lock+0x39/0x1d0 [ 46.020096] ? lock_downgrade+0x990/0x990 [ 46.024207] ? recalc_sigpending_tsk+0x117/0x150 [ 46.028927] ? recalc_sigpending+0x103/0x160 [ 46.033298] ? recalc_sigpending_tsk+0x150/0x150 [ 46.038014] ? get_signal+0x2b2/0x16d0 [ 46.041865] do_group_exit+0x149/0x400 [ 46.045714] ? __lock_is_held+0xbc/0x140 [ 46.049734] ? SyS_exit+0x30/0x30 [ 46.053149] ? _raw_spin_unlock_irq+0x27/0x70 [ 46.057609] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 46.062587] get_signal+0x73f/0x16d0 [ 46.066264] ? ptrace_notify+0x130/0x130 [ 46.070288] ? find_held_lock+0x39/0x1d0 [ 46.074312] ? exit_robust_list+0x240/0x240 [ 46.078597] ? lock_downgrade+0x990/0x990 [ 46.082707] ? lock_downgrade+0x990/0x990 [ 46.086819] do_signal+0x94/0x1ee0 [ 46.090321] ? cpuset_wait_for_hotplug+0x20/0x20 [ 46.095040] ? find_held_lock+0x39/0x1d0 [ 46.099065] ? setup_sigcontext+0x7d0/0x7d0