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-4,10.128.15.202' (ECDSA) to the list of known hosts. 2017/10/01 22:59:45 parsed 1 programs 2017/10/01 22:59:45 executed programs: 0 syzkaller login: [ 33.691150] ================================================================== [ 33.698546] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 33.705192] Read of size 8 at addr ffff8801d1aa2428 by task syz-executor4/5089 [ 33.712525] [ 33.714137] CPU: 1 PID: 5089 Comm: syz-executor4 Not tainted 4.14.0-rc2-mm1+ #11 [ 33.721643] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.730971] Call Trace: [ 33.733535] dump_stack+0x194/0x257 [ 33.737146] ? arch_local_irq_restore+0x53/0x53 [ 33.742295] ? show_regs_print_info+0x65/0x65 [ 33.746759] ? __kernel_text_address+0xd/0x40 [ 33.751227] ? __lock_acquire+0x407b/0x4620 [ 33.755525] print_address_description+0x73/0x250 [ 33.760349] ? __lock_acquire+0x407b/0x4620 [ 33.764645] kasan_report+0x25b/0x340 [ 33.768415] __asan_report_load8_noabort+0x14/0x20 [ 33.773313] __lock_acquire+0x407b/0x4620 [ 33.777441] ? unwind_dump+0x4c0/0x4c0 [ 33.781309] ? __unwind_start+0x169/0x330 [ 33.785448] ? __kernel_text_address+0xd/0x40 [ 33.789921] ? unwind_get_return_address+0x61/0xa0 [ 33.794837] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.800005] ? unwind_get_return_address+0x61/0xa0 [ 33.804911] ? __save_stack_trace+0x61/0xd0 [ 33.809209] ? get_signal+0x73f/0x16d0 [ 33.813072] ? save_stack_trace+0x16/0x20 [ 33.817194] ? __lock_acquire+0x20fd/0x4620 [ 33.821491] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.826650] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.831811] ? save_stack_trace+0x16/0x20 [ 33.835928] ? __lock_acquire+0x20fd/0x4620 [ 33.840217] ? osq_unlock+0x350/0x350 [ 33.843982] ? save_stack_trace+0x16/0x20 [ 33.848099] ? check_noncircular+0x20/0x20 [ 33.852305] ? check_noncircular+0x20/0x20 [ 33.856513] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.861682] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.866855] ? find_held_lock+0x39/0x1d0 [ 33.870904] ? lock_downgrade+0x990/0x990 [ 33.875036] ? check_noncircular+0x20/0x20 [ 33.879256] lock_acquire+0x1d5/0x580 [ 33.883041] ? exit_pi_state_list+0x369/0x7a0 [ 33.887514] ? lock_release+0xd70/0xd70 [ 33.891462] ? do_raw_spin_trylock+0x190/0x190 [ 33.896026] ? find_held_lock+0x39/0x1d0 [ 33.900077] _raw_spin_lock_irq+0x5e/0x80 [ 33.904204] ? exit_pi_state_list+0x369/0x7a0 [ 33.908680] exit_pi_state_list+0x369/0x7a0 [ 33.912981] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 33.919010] ? lock_release+0xd70/0xd70 [ 33.922961] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 33.928816] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 33.933889] ? __might_sleep+0x95/0x190 [ 33.937841] ? __might_fault+0x188/0x1d0 [ 33.941879] ? do_raw_spin_trylock+0x190/0x190 [ 33.946435] mm_release+0x46d/0x590 [ 33.950041] ? do_raw_spin_trylock+0x190/0x190 [ 33.954597] ? mm_access+0x140/0x140 [ 33.958279] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.962750] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.967746] ? trace_hardirqs_on+0xd/0x10 [ 33.971875] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.976349] ? acct_collect+0x637/0x800 [ 33.980300] do_exit+0x481/0x1b00 [ 33.983723] ? mm_update_next_owner+0x930/0x930 [ 33.988357] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 33.994211] ? rcu_note_context_switch+0x710/0x710 [ 33.999112] ? futex_wait_setup+0x14a/0x3d0 [ 34.003399] ? __might_sleep+0x95/0x190 [ 34.007339] ? _cond_resched+0x14/0x30 [ 34.011189] ? futex_wait_queue_me+0x524/0x7e0 [ 34.015735] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 34.021061] ? memset+0x31/0x40 [ 34.024305] ? check_noncircular+0x20/0x20 [ 34.028508] ? futex_wait_setup+0x22e/0x3d0 [ 34.032797] ? futex_wake+0x680/0x680 [ 34.036561] ? find_held_lock+0x39/0x1d0 [ 34.040589] ? lock_downgrade+0x990/0x990 [ 34.044702] ? recalc_sigpending_tsk+0x117/0x150 [ 34.049422] ? recalc_sigpending+0x103/0x160 [ 34.053794] ? recalc_sigpending_tsk+0x150/0x150 [ 34.058514] ? get_signal+0x2b2/0x16d0 [ 34.062370] do_group_exit+0x149/0x400 [ 34.066222] ? __lock_is_held+0xbc/0x140 [ 34.070245] ? SyS_exit+0x30/0x30 [ 34.073664] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.078126] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.083106] get_signal+0x73f/0x16d0 [ 34.086785] ? ptrace_notify+0x130/0x130 [ 34.090812] ? __schedule+0x8f0/0x2070 [ 34.094669] ? exit_robust_list+0x240/0x240 [ 34.098963] ? check_noncircular+0x20/0x20 [ 34.103171] do_signal+0x94/0x1ee0 [ 34.106682] ? find_held_lock+0x39/0x1d0 [ 34.110715] ? setup_sigcontext+0x7d0/0x7d0 [ 34.115004] ? lock_downgrade+0x990/0x990 [ 34.119128] ? lock_release+0xd70/0xd70 [ 34.123072] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 34.128924] ? lock_acquire+0x1d5/0x580 [ 34.132868] ? finish_task_switch+0x1aa/0x740 [ 34.137337] ? exit_to_usermode_loop+0x8c/0x310 [ 34.141980] exit_to_usermode_loop+0x214/0x310 [ 34.146526] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 34.152034] ? kasan_check_write+0x14/0x20 [ 34.156237] syscall_return_slowpath+0x42f/0x510 [ 34.160956] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 34.165939] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 34.170837] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.175820] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 34.180542] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 34.185268] RIP: 0033:0x4520a9 [ 34.188431] RSP: 002b:00007ff33be0acf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 34.196102] RAX: 0000000000000000 RBX: 0000000000718188 RCX: 00000000004520a9 [ 34.203337] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718188 [ 34.210572] RBP: 0000000000718160 R08: 0000000000000000 R09: 0000000000000000 [ 34.217806] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 34.225042] R13: 00007fff851f249f R14: 00007ff33be0b9c0 R15: 0000000000000003 [ 34.232282] [ 34.233877] Allocated by task 5105: [ 34.237468] save_stack_trace+0x16/0x20 [ 34.241407] save_stack+0x43/0xd0 [ 34.244822] kasan_kmalloc+0xad/0xe0 [ 34.248501] kmem_cache_alloc_trace+0x136/0x750 [ 34.253135] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 34.258202] futex_requeue+0x1887/0x2370 [ 34.262225] do_futex+0x7f5/0x20d0 [ 34.265728] SyS_futex+0x260/0x390 [ 34.269233] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 34.273950] [ 34.275542] Freed by task 5083: [ 34.278786] save_stack_trace+0x16/0x20 [ 34.282721] save_stack+0x43/0xd0 [ 34.286138] kasan_slab_free+0x71/0xc0 [ 34.289986] kfree+0xca/0x250 [ 34.293054] put_pi_state+0x3f4/0x560 [ 34.296817] unqueue_me_pi+0x4a/0xc0 [ 34.300493] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 34.306253] do_futex+0x825/0x20d0 [ 34.309754] SyS_futex+0x260/0x390 [ 34.313260] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 34.317978] [ 34.319572] The buggy address belongs to the object at ffff8801d1aa2400 [ 34.319572] which belongs to the cache kmalloc-256 of size 256 [ 34.332193] The buggy address is located 40 bytes inside of [ 34.332193] 256-byte region [ffff8801d1aa2400, ffff8801d1aa2500) [ 34.343941] The buggy address belongs to the page: [ 34.348835] page:ffffea000746a880 count:1 mapcount:0 mapping:ffff8801d1aa2040 index:0x0 [ 34.356937] flags: 0x200000000000100(slab) [ 34.361139] raw: 0200000000000100 ffff8801d1aa2040 0000000000000000 000000010000000c [ 34.368982] raw: ffffea0007229fa0 ffffea00072145e0 ffff8801dac007c0 0000000000000000 [ 34.376822] page dumped because: kasan: bad access detected [ 34.382499] [ 34.384090] Memory state around the buggy address: [ 34.388984] ffff8801d1aa2300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.396305] ffff8801d1aa2380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 34.403627] >ffff8801d1aa2400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.410947] ^ [ 34.415578] ffff8801d1aa2480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.422899] ffff8801d1aa2500: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 34.430219] ================================================================== [ 34.437537] Disabling lock debugging due to kernel taint [ 34.442950] Kernel panic - not syncing: panic_on_warn set ... [ 34.442950] [ 34.450280] CPU: 1 PID: 5089 Comm: syz-executor4 Tainted: G B 4.14.0-rc2-mm1+ #11 [ 34.458997] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.468319] Call Trace: [ 34.470884] dump_stack+0x194/0x257 [ 34.474475] ? arch_local_irq_restore+0x53/0x53 [ 34.479111] ? vprintk_default+0x28/0x30 [ 34.483137] ? __lock_acquire+0x4060/0x4620 [ 34.487423] panic+0x1e4/0x41c [ 34.490581] ? refcount_error_report+0x214/0x214 [ 34.495305] ? __lock_acquire+0x407b/0x4620 [ 34.499592] kasan_end_report+0x50/0x50 [ 34.503531] kasan_report+0x144/0x340 [ 34.507297] __asan_report_load8_noabort+0x14/0x20 [ 34.512190] __lock_acquire+0x407b/0x4620 [ 34.516303] ? unwind_dump+0x4c0/0x4c0 [ 34.520155] ? __unwind_start+0x169/0x330 [ 34.524268] ? __kernel_text_address+0xd/0x40 [ 34.528728] ? unwind_get_return_address+0x61/0xa0 [ 34.533621] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.538774] ? unwind_get_return_address+0x61/0xa0 [ 34.543667] ? __save_stack_trace+0x61/0xd0 [ 34.547954] ? get_signal+0x73f/0x16d0 [ 34.551805] ? save_stack_trace+0x16/0x20 [ 34.555916] ? __lock_acquire+0x20fd/0x4620 [ 34.560201] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.565356] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.570507] ? save_stack_trace+0x16/0x20 [ 34.574620] ? __lock_acquire+0x20fd/0x4620 [ 34.578903] ? osq_unlock+0x350/0x350 [ 34.582667] ? save_stack_trace+0x16/0x20 [ 34.586780] ? check_noncircular+0x20/0x20 [ 34.590980] ? check_noncircular+0x20/0x20 [ 34.595179] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.600333] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.605494] ? find_held_lock+0x39/0x1d0 [ 34.609521] ? lock_downgrade+0x990/0x990 [ 34.613632] ? check_noncircular+0x20/0x20 [ 34.617830] lock_acquire+0x1d5/0x580 [ 34.621594] ? exit_pi_state_list+0x369/0x7a0 [ 34.626054] ? lock_release+0xd70/0xd70 [ 34.629989] ? do_raw_spin_trylock+0x190/0x190 [ 34.634535] ? find_held_lock+0x39/0x1d0 [ 34.638564] _raw_spin_lock_irq+0x5e/0x80 [ 34.642674] ? exit_pi_state_list+0x369/0x7a0 [ 34.647132] exit_pi_state_list+0x369/0x7a0 [ 34.651419] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 34.657440] ? lock_release+0xd70/0xd70 [ 34.661378] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 34.667225] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 34.672291] ? __might_sleep+0x95/0x190 [ 34.676229] ? __might_fault+0x188/0x1d0 [ 34.680268] ? do_raw_spin_trylock+0x190/0x190 [ 34.684816] mm_release+0x46d/0x590 [ 34.688404] ? do_raw_spin_trylock+0x190/0x190