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-next-kasan-gce-6,10.128.15.222' (ECDSA) to the list of known hosts. 2017/09/27 19:18:35 parsed 1 programs 2017/09/27 19:18:35 executed programs: 0 syzkaller login: [ 37.206368] ================================================================== [ 37.213760] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 37.220402] Read of size 8 at addr ffff8801cbb55868 by task syz-executor4/3708 [ 37.227733] [ 37.229338] CPU: 1 PID: 3708 Comm: syz-executor4 Not tainted 4.14.0-rc2-next-20170927+ #30 [ 37.237714] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 37.247037] Call Trace: [ 37.249599] dump_stack+0x194/0x257 [ 37.253199] ? arch_local_irq_restore+0x53/0x53 [ 37.257844] ? show_regs_print_info+0x65/0x65 [ 37.262317] ? __kernel_text_address+0xd/0x40 [ 37.266802] ? __lock_acquire+0x407b/0x4620 [ 37.271107] print_address_description+0x73/0x250 [ 37.275917] ? __lock_acquire+0x407b/0x4620 [ 37.280217] kasan_report+0x25b/0x340 [ 37.284009] __asan_report_load8_noabort+0x14/0x20 [ 37.288920] __lock_acquire+0x407b/0x4620 [ 37.293050] ? unwind_dump+0x4c0/0x4c0 [ 37.296912] ? __unwind_start+0x169/0x330 [ 37.301036] ? __kernel_text_address+0xd/0x40 [ 37.305518] ? unwind_get_return_address+0x61/0xa0 [ 37.310442] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 37.315608] ? unwind_get_return_address+0x61/0xa0 [ 37.320504] ? __save_stack_trace+0x61/0xd0 [ 37.324793] ? get_signal+0x73f/0x16d0 [ 37.329600] ? save_stack_trace+0x16/0x20 [ 37.333733] ? __lock_acquire+0x20fd/0x4620 [ 37.338043] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 37.343204] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 37.348362] ? save_stack_trace+0x16/0x20 [ 37.352477] ? __lock_acquire+0x20fd/0x4620 [ 37.356766] ? osq_unlock+0x350/0x350 [ 37.360542] ? save_stack_trace+0x16/0x20 [ 37.364671] ? lock_release+0xd70/0xd70 [ 37.368615] ? check_noncircular+0x20/0x20 [ 37.372818] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 37.377976] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 37.383137] ? find_held_lock+0x39/0x1d0 [ 37.387171] ? lock_downgrade+0x990/0x990 [ 37.391288] ? check_noncircular+0x20/0x20 [ 37.395489] lock_acquire+0x1d5/0x580 [ 37.399258] ? exit_pi_state_list+0x369/0x7a0 [ 37.403721] ? lock_release+0xd70/0xd70 [ 37.407667] ? do_raw_spin_trylock+0x190/0x190 [ 37.412215] ? find_held_lock+0x39/0x1d0 [ 37.416246] _raw_spin_lock_irq+0x5e/0x80 [ 37.420360] ? exit_pi_state_list+0x369/0x7a0 [ 37.424821] exit_pi_state_list+0x369/0x7a0 [ 37.429127] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 37.435160] ? lock_release+0xd70/0xd70 [ 37.439104] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 37.444953] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 37.450031] ? __might_sleep+0x95/0x190 [ 37.453981] ? __might_fault+0x188/0x1d0 [ 37.458015] ? do_raw_spin_trylock+0x190/0x190 [ 37.462572] mm_release+0x46d/0x590 [ 37.466167] ? do_raw_spin_trylock+0x190/0x190 [ 37.470714] ? mm_access+0x140/0x140 [ 37.474403] ? _raw_spin_unlock_irq+0x27/0x70 [ 37.478880] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 37.483864] ? trace_hardirqs_on+0xd/0x10 [ 37.487995] ? _raw_spin_unlock_irq+0x27/0x70 [ 37.492469] ? acct_collect+0x637/0x800 [ 37.496411] do_exit+0x481/0x1b00 [ 37.499841] ? mm_update_next_owner+0x930/0x930 [ 37.504487] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 37.510345] ? find_held_lock+0x39/0x1d0 [ 37.514378] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 37.519718] ? check_noncircular+0x20/0x20 [ 37.523934] ? fault_in_user_writeable+0x90/0x90 [ 37.528666] ? futex_wake+0x680/0x680 [ 37.532437] ? find_held_lock+0x39/0x1d0 [ 37.536468] ? lock_downgrade+0x990/0x990 [ 37.540586] ? recalc_sigpending_tsk+0x117/0x150 [ 37.545321] ? recalc_sigpending+0x103/0x160 [ 37.549711] ? recalc_sigpending_tsk+0x150/0x150 [ 37.554432] ? get_signal+0x2b2/0x16d0 [ 37.558289] do_group_exit+0x149/0x400 [ 37.562142] ? __lock_is_held+0xbc/0x140 [ 37.566168] ? SyS_exit+0x30/0x30 [ 37.569595] ? _raw_spin_unlock_irq+0x27/0x70 [ 37.574068] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 37.579060] get_signal+0x73f/0x16d0 [ 37.582747] ? ptrace_notify+0x130/0x130 [ 37.586778] ? exit_robust_list+0x240/0x240 [ 37.591069] ? wake_up_q+0x8a/0xe0 [ 37.594598] ? rwsem_wake+0x313/0x520 [ 37.598365] ? SyS_brk+0x6f0/0x6f0 [ 37.601874] do_signal+0x94/0x1ee0 [ 37.605379] ? arch_get_unmapped_area+0x750/0x750 [ 37.610186] ? lock_acquire+0x1d5/0x580 [ 37.614128] ? vm_mmap_pgoff+0x198/0x280 [ 37.618168] ? userfaultfd_unmap_complete+0x327/0x510 [ 37.623333] ? setup_sigcontext+0x7d0/0x7d0 [ 37.627623] ? userfaultfd_unmap_prep+0x540/0x540 [ 37.632433] ? call_rwsem_wake+0x1b/0x30 [ 37.636462] ? vma_compute_subtree_gap+0x200/0x200 [ 37.641388] ? up_write+0xd8/0x120 [ 37.644908] ? down_write+0x120/0x120 [ 37.648688] ? security_mmap_file+0x143/0x180 [ 37.653159] ? vm_mmap_pgoff+0x1fc/0x280 [ 37.657191] ? exit_to_usermode_loop+0x8c/0x310 [ 37.661827] exit_to_usermode_loop+0x214/0x310 [ 37.666381] ? vma_is_stack_for_current+0xa0/0xa0 [ 37.671195] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 37.676707] ? kasan_check_write+0x14/0x20 [ 37.680910] syscall_return_slowpath+0x42f/0x510 [ 37.685637] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 37.690627] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 37.695525] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 37.700505] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 37.705227] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 37.709951] RIP: 0033:0x4520a9 [ 37.713114] RSP: 002b:00007f0b6f6bfcf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 37.720786] RAX: fffffffffffffe00 RBX: 00000000007180d8 RCX: 00000000004520a9 [ 37.728028] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000007180d8 [ 37.735270] RBP: 00000000007180b0 R08: 0000000000000000 R09: 0000000000000000 [ 37.742506] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 37.749743] R13: 00007ffc5848bddf R14: 00007f0b6f6c09c0 R15: 0000000000000002 [ 37.756991] [ 37.758597] Allocated by task 3734: [ 37.762216] save_stack_trace+0x16/0x20 [ 37.766174] save_stack+0x43/0xd0 [ 37.769592] kasan_kmalloc+0xad/0xe0 [ 37.773271] kmem_cache_alloc_trace+0x136/0x750 [ 37.777909] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 37.782990] futex_requeue+0x1887/0x2370 [ 37.787035] do_futex+0x7f5/0x20d0 [ 37.790544] SyS_futex+0x260/0x390 [ 37.794055] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 37.798784] [ 37.800377] Freed by task 3714: [ 37.803624] save_stack_trace+0x16/0x20 [ 37.807568] save_stack+0x43/0xd0 [ 37.810987] kasan_slab_free+0x71/0xc0 [ 37.814866] kfree+0xca/0x250 [ 37.817939] put_pi_state+0x3f4/0x560 [ 37.821703] unqueue_me_pi+0x4a/0xc0 [ 37.825381] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 37.831147] do_futex+0x825/0x20d0 [ 37.834665] SyS_futex+0x260/0x390 [ 37.838172] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 37.842903] [ 37.844498] The buggy address belongs to the object at ffff8801cbb55840 [ 37.844498] which belongs to the cache kmalloc-256 of size 256 [ 37.857121] The buggy address is located 40 bytes inside of [ 37.857121] 256-byte region [ffff8801cbb55840, ffff8801cbb55940) [ 37.868872] The buggy address belongs to the page: [ 37.873774] page:ffffea00072ed540 count:1 mapcount:0 mapping:ffff8801cbb550c0 index:0x0 [ 37.881890] flags: 0x200000000000100(slab) [ 37.886091] raw: 0200000000000100 ffff8801cbb550c0 0000000000000000 000000010000000c [ 37.893940] raw: ffffea00072da820 ffffea00072d7ee0 ffff8801dac007c0 0000000000000000 [ 37.901793] page dumped because: kasan: bad access detected [ 37.907465] [ 37.909059] Memory state around the buggy address: [ 37.913954] ffff8801cbb55700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 37.921300] ffff8801cbb55780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 37.928633] >ffff8801cbb55800: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 37.935969] ^ [ 37.942686] ffff8801cbb55880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 37.950019] ffff8801cbb55900: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 37.957347] ================================================================== [ 37.964669] Disabling lock debugging due to kernel taint [ 37.970084] Kernel panic - not syncing: panic_on_warn set ... [ 37.970084] [ 37.977420] CPU: 1 PID: 3708 Comm: syz-executor4 Tainted: G B 4.14.0-rc2-next-20170927+ #30 [ 37.986999] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 37.996338] Call Trace: [ 37.998895] dump_stack+0x194/0x257 [ 38.002490] ? arch_local_irq_restore+0x53/0x53 [ 38.007126] ? vprintk_default+0x28/0x30 [ 38.011162] ? __lock_acquire+0x3f80/0x4620 [ 38.015457] panic+0x1e4/0x417 [ 38.018616] ? __warn+0x1d9/0x1d9 [ 38.022041] ? __lock_acquire+0x407b/0x4620 [ 38.026328] kasan_end_report+0x50/0x50 [ 38.030266] kasan_report+0x144/0x340 [ 38.034050] __asan_report_load8_noabort+0x14/0x20 [ 38.038963] __lock_acquire+0x407b/0x4620 [ 38.043079] ? unwind_dump+0x4c0/0x4c0 [ 38.046930] ? __unwind_start+0x169/0x330 [ 38.051056] ? __kernel_text_address+0xd/0x40 [ 38.055517] ? unwind_get_return_address+0x61/0xa0 [ 38.060420] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.065578] ? unwind_get_return_address+0x61/0xa0 [ 38.070474] ? __save_stack_trace+0x61/0xd0 [ 38.074762] ? get_signal+0x73f/0x16d0 [ 38.078616] ? save_stack_trace+0x16/0x20 [ 38.082745] ? __lock_acquire+0x20fd/0x4620 [ 38.087044] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.092202] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.097357] ? save_stack_trace+0x16/0x20 [ 38.101483] ? __lock_acquire+0x20fd/0x4620 [ 38.105787] ? osq_unlock+0x350/0x350 [ 38.109557] ? save_stack_trace+0x16/0x20 [ 38.113682] ? lock_release+0xd70/0xd70 [ 38.117626] ? check_noncircular+0x20/0x20 [ 38.121826] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.126988] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.132148] ? find_held_lock+0x39/0x1d0 [ 38.136179] ? lock_downgrade+0x990/0x990 [ 38.140293] ? check_noncircular+0x20/0x20 [ 38.144493] lock_acquire+0x1d5/0x580 [ 38.148265] ? exit_pi_state_list+0x369/0x7a0 [ 38.152729] ? lock_release+0xd70/0xd70 [ 38.156668] ? do_raw_spin_trylock+0x190/0x190 [ 38.161215] ? find_held_lock+0x39/0x1d0 [ 38.165259] _raw_spin_lock_irq+0x5e/0x80 [ 38.169383] ? exit_pi_state_list+0x369/0x7a0 [ 38.173864] exit_pi_state_list+0x369/0x7a0 [ 38.178154] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 38.184191] ? lock_release+0xd70/0xd70 [ 38.188134] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 38.193989] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 38.199065] ? __might_sleep+0x95/0x190 [ 38.203007] ? __might_fault+0x188/0x1d0