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-2,10.128.0.6' (ECDSA) to the list of known hosts. 2017/09/28 03:58:49 parsed 1 programs 2017/09/28 03:58:49 executed programs: 0 syzkaller login: [ 33.540249] ================================================================== [ 33.547666] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 33.554299] Read of size 8 at addr ffff8801cbe43068 by task syz-executor4/3594 [ 33.561620] [ 33.563216] CPU: 0 PID: 3594 Comm: syz-executor4 Not tainted 4.14.0-rc2-next-20170927+ #30 [ 33.571580] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.580900] Call Trace: [ 33.583456] dump_stack+0x194/0x257 [ 33.587050] ? arch_local_irq_restore+0x53/0x53 [ 33.591682] ? show_regs_print_info+0x65/0x65 [ 33.596144] ? __kernel_text_address+0xd/0x40 [ 33.600606] ? __lock_acquire+0x407b/0x4620 [ 33.604894] print_address_description+0x73/0x250 [ 33.609699] ? __lock_acquire+0x407b/0x4620 [ 33.613984] kasan_report+0x25b/0x340 [ 33.617751] __asan_report_load8_noabort+0x14/0x20 [ 33.622644] __lock_acquire+0x407b/0x4620 [ 33.626759] ? unwind_dump+0x4c0/0x4c0 [ 33.630609] ? __unwind_start+0x169/0x330 [ 33.634721] ? __kernel_text_address+0xd/0x40 [ 33.639179] ? unwind_get_return_address+0x61/0xa0 [ 33.644098] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.649259] ? unwind_get_return_address+0x61/0xa0 [ 33.654159] ? __save_stack_trace+0x61/0xd0 [ 33.658448] ? get_signal+0x73f/0x16d0 [ 33.662302] ? save_stack_trace+0x16/0x20 [ 33.666419] ? __lock_acquire+0x20fd/0x4620 [ 33.670706] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.675876] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.681044] ? save_stack_trace+0x16/0x20 [ 33.685160] ? __lock_acquire+0x20fd/0x4620 [ 33.689448] ? osq_unlock+0x350/0x350 [ 33.693212] ? save_stack_trace+0x16/0x20 [ 33.697334] ? check_noncircular+0x20/0x20 [ 33.701535] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.706689] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.711850] ? __sys_recvmsg+0xe2/0x210 [ 33.715795] ? save_stack_trace+0x16/0x20 [ 33.719907] ? __lock_acquire+0x20fd/0x4620 [ 33.724192] ? find_held_lock+0x39/0x1d0 [ 33.728230] ? lock_downgrade+0x990/0x990 [ 33.732350] ? check_noncircular+0x20/0x20 [ 33.736557] lock_acquire+0x1d5/0x580 [ 33.740328] ? exit_pi_state_list+0x369/0x7a0 [ 33.744791] ? lock_release+0xd70/0xd70 [ 33.748729] ? do_raw_spin_trylock+0x190/0x190 [ 33.753278] ? find_held_lock+0x39/0x1d0 [ 33.757314] _raw_spin_lock_irq+0x5e/0x80 [ 33.761426] ? exit_pi_state_list+0x369/0x7a0 [ 33.765885] exit_pi_state_list+0x369/0x7a0 [ 33.770180] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 33.776204] ? lock_release+0xd70/0xd70 [ 33.780144] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 33.785993] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 33.791064] ? __might_sleep+0x95/0x190 [ 33.795009] ? __might_fault+0x188/0x1d0 [ 33.799045] ? do_raw_spin_trylock+0x190/0x190 [ 33.803592] mm_release+0x46d/0x590 [ 33.807181] ? do_raw_spin_trylock+0x190/0x190 [ 33.811735] ? mm_access+0x140/0x140 [ 33.815419] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.819880] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.824862] ? trace_hardirqs_on+0xd/0x10 [ 33.828977] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.833436] ? acct_collect+0x637/0x800 [ 33.837377] do_exit+0x481/0x1b00 [ 33.840800] ? receiver_wake_function+0x70/0x70 [ 33.845435] ? mm_update_next_owner+0x930/0x930 [ 33.850069] ? __skb_try_recv_from_queue+0x8a0/0x960 [ 33.855137] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 33.860987] ? skb_segment+0x2f70/0x2f70 [ 33.865020] ? futex_wait_setup+0x14a/0x3d0 [ 33.869315] ? _raw_spin_unlock+0x22/0x30 [ 33.873430] ? unix_dgram_recvmsg+0x461/0x1990 [ 33.877983] ? _cond_resched+0x14/0x30 [ 33.881856] ? check_noncircular+0x20/0x20 [ 33.886056] ? unix_getname+0x290/0x290 [ 33.890001] ? check_noncircular+0x20/0x20 [ 33.894212] ? futex_wait_setup+0x22e/0x3d0 [ 33.898510] ? find_held_lock+0x39/0x1d0 [ 33.902541] ? lock_downgrade+0x990/0x990 [ 33.906654] ? recalc_sigpending_tsk+0x117/0x150 [ 33.911374] ? recalc_sigpending+0x103/0x160 [ 33.915749] ? recalc_sigpending_tsk+0x150/0x150 [ 33.920470] ? get_signal+0x2b2/0x16d0 [ 33.924328] do_group_exit+0x149/0x400 [ 33.928180] ? __lock_is_held+0xbc/0x140 [ 33.932209] ? SyS_exit+0x30/0x30 [ 33.935627] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.940089] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.945070] get_signal+0x73f/0x16d0 [ 33.948759] ? ptrace_notify+0x130/0x130 [ 33.952800] ? rcu_pm_notify+0xc0/0xc0 [ 33.956662] ? ___sys_recvmsg+0x41e/0x630 [ 33.960778] ? rcu_read_lock_sched_held+0x108/0x120 [ 33.965767] ? kfree+0x1e7/0x250 [ 33.969099] ? ___sys_recvmsg+0x423/0x630 [ 33.973220] do_signal+0x94/0x1ee0 [ 33.976731] ? ___sys_sendmsg+0x8a0/0x8a0 [ 33.980853] ? setup_sigcontext+0x7d0/0x7d0 [ 33.985146] ? __fget_light+0x29d/0x390 [ 33.989087] ? fget_raw+0x20/0x20 [ 33.992513] ? __fd_install+0x2f7/0x6a0 [ 33.996459] ? get_unused_fd_flags+0x190/0x190 [ 34.001014] ? exit_to_usermode_loop+0x8c/0x310 [ 34.005656] exit_to_usermode_loop+0x214/0x310 [ 34.010207] ? __sys_recvmsg+0x138/0x210 [ 34.014239] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 34.019743] ? __might_sleep+0x95/0x190 [ 34.023692] syscall_return_slowpath+0x42f/0x510 [ 34.028412] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 34.033393] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 34.038290] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.043268] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 34.047990] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 34.052709] RIP: 0033:0x4520a9 [ 34.055864] RSP: 002b:00007f5366d6bc08 EFLAGS: 00000216 ORIG_RAX: 000000000000002f [ 34.063532] RAX: fffffffffffffe00 RBX: 0000000000718000 RCX: 00000000004520a9 [ 34.070766] RDX: 0000000000000000 RSI: 0000000020d5f000 RDI: 0000000000000004 [ 34.078000] RBP: 00000000000045a0 R08: 0000000000000000 R09: 0000000000000000 [ 34.085239] R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004bab75 [ 34.092472] R13: 00000000ffffffff R14: 0000000000000004 R15: 0000000020d5f000 [ 34.099712] [ 34.101315] Allocated by task 3611: [ 34.104909] save_stack_trace+0x16/0x20 [ 34.108846] save_stack+0x43/0xd0 [ 34.112262] kasan_kmalloc+0xad/0xe0 [ 34.115939] kmem_cache_alloc_trace+0x136/0x750 [ 34.120571] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 34.125635] futex_requeue+0x1887/0x2370 [ 34.129658] do_futex+0x7f5/0x20d0 [ 34.133163] SyS_futex+0x260/0x390 [ 34.136669] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 34.141385] [ 34.142982] Freed by task 3604: [ 34.146234] save_stack_trace+0x16/0x20 [ 34.150171] save_stack+0x43/0xd0 [ 34.153585] kasan_slab_free+0x71/0xc0 [ 34.157435] kfree+0xca/0x250 [ 34.160503] put_pi_state+0x3f4/0x560 [ 34.164267] unqueue_me_pi+0x4a/0xc0 [ 34.167942] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 34.173701] do_futex+0x825/0x20d0 [ 34.177205] SyS_futex+0x260/0x390 [ 34.180710] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 34.185433] [ 34.187029] The buggy address belongs to the object at ffff8801cbe43040 [ 34.187029] which belongs to the cache kmalloc-256 of size 256 [ 34.199649] The buggy address is located 40 bytes inside of [ 34.199649] 256-byte region [ffff8801cbe43040, ffff8801cbe43140) [ 34.211405] The buggy address belongs to the page: [ 34.216296] page:ffffea00072f90c0 count:1 mapcount:0 mapping:ffff8801cbe43040 index:0x0 [ 34.224410] flags: 0x200000000000100(slab) [ 34.228612] raw: 0200000000000100 ffff8801cbe43040 0000000000000000 000000010000000c [ 34.236459] raw: ffffea00072f9560 ffffea00072e4a20 ffff8801dac007c0 0000000000000000 [ 34.244302] page dumped because: kasan: bad access detected [ 34.249972] [ 34.251562] Memory state around the buggy address: [ 34.256454] ffff8801cbe42f00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 34.263779] ffff8801cbe42f80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 34.271101] >ffff8801cbe43000: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 34.278422] ^ [ 34.285137] ffff8801cbe43080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.292460] ffff8801cbe43100: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 34.299779] ================================================================== [ 34.307098] Disabling lock debugging due to kernel taint [ 34.312511] Kernel panic - not syncing: panic_on_warn set ... [ 34.312511] [ 34.319835] CPU: 0 PID: 3594 Comm: syz-executor4 Tainted: G B 4.14.0-rc2-next-20170927+ #30 [ 34.329420] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.338736] Call Trace: [ 34.341290] dump_stack+0x194/0x257 [ 34.344883] ? arch_local_irq_restore+0x53/0x53 [ 34.349517] ? vprintk_default+0x28/0x30 [ 34.353544] ? __lock_acquire+0x3f80/0x4620 [ 34.357830] panic+0x1e4/0x417 [ 34.360985] ? __warn+0x1d9/0x1d9 [ 34.364406] ? __lock_acquire+0x407b/0x4620 [ 34.368692] kasan_end_report+0x50/0x50 [ 34.372633] kasan_report+0x144/0x340 [ 34.376401] __asan_report_load8_noabort+0x14/0x20 [ 34.381295] __lock_acquire+0x407b/0x4620 [ 34.385407] ? unwind_dump+0x4c0/0x4c0 [ 34.389256] ? __unwind_start+0x169/0x330 [ 34.393369] ? __kernel_text_address+0xd/0x40 [ 34.397827] ? unwind_get_return_address+0x61/0xa0 [ 34.402721] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.407874] ? unwind_get_return_address+0x61/0xa0 [ 34.412774] ? __save_stack_trace+0x61/0xd0 [ 34.417060] ? get_signal+0x73f/0x16d0 [ 34.420910] ? save_stack_trace+0x16/0x20 [ 34.425023] ? __lock_acquire+0x20fd/0x4620 [ 34.429311] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.434467] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.439622] ? save_stack_trace+0x16/0x20 [ 34.443735] ? __lock_acquire+0x20fd/0x4620 [ 34.448025] ? osq_unlock+0x350/0x350 [ 34.451788] ? save_stack_trace+0x16/0x20 [ 34.455903] ? check_noncircular+0x20/0x20 [ 34.460103] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.465258] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.470413] ? __sys_recvmsg+0xe2/0x210 [ 34.474354] ? save_stack_trace+0x16/0x20 [ 34.478464] ? __lock_acquire+0x20fd/0x4620 [ 34.482748] ? find_held_lock+0x39/0x1d0 [ 34.486776] ? lock_downgrade+0x990/0x990 [ 34.490886] ? check_noncircular+0x20/0x20 [ 34.495085] lock_acquire+0x1d5/0x580 [ 34.498850] ? exit_pi_state_list+0x369/0x7a0 [ 34.503312] ? lock_release+0xd70/0xd70 [ 34.507248] ? do_raw_spin_trylock+0x190/0x190 [ 34.511794] ? find_held_lock+0x39/0x1d0 [ 34.515821] _raw_spin_lock_irq+0x5e/0x80 [ 34.519933] ? exit_pi_state_list+0x369/0x7a0 [ 34.524389] exit_pi_state_list+0x369/0x7a0 [ 34.528677] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 34.534699] ? lock_release+0xd70/0xd70 [ 34.538644] ? trace_event_raw_event_sched_switch+0x770/0x770