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-kasan-gce-386-3,10.128.15.197' (ECDSA) to the list of known hosts. 2017/10/04 08:57:11 parsed 1 programs 2017/10/04 08:57:11 executed programs: 0 syzkaller login: [ 38.864353] ================================================================== [ 38.871765] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 38.878411] Read of size 8 at addr ffff8801c51adbe8 by task syz-executor2/4435 [ 38.885740] [ 38.887347] CPU: 0 PID: 4435 Comm: syz-executor2 Not tainted 4.14.0-rc3+ #24 [ 38.894512] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 38.903840] Call Trace: [ 38.906401] dump_stack+0x194/0x257 [ 38.910012] ? arch_local_irq_restore+0x53/0x53 [ 38.914659] ? show_regs_print_info+0x65/0x65 [ 38.919130] ? __kernel_text_address+0xd/0x40 [ 38.923599] ? __lock_acquire+0x407b/0x4620 [ 38.927891] print_address_description+0x73/0x250 [ 38.932699] ? __lock_acquire+0x407b/0x4620 [ 38.936987] kasan_report+0x25b/0x340 [ 38.940760] __asan_report_load8_noabort+0x14/0x20 [ 38.945668] __lock_acquire+0x407b/0x4620 [ 38.949797] ? unwind_dump+0x4c0/0x4c0 [ 38.953662] ? __kernel_text_address+0xd/0x40 [ 38.958122] ? unwind_get_return_address+0x61/0xa0 [ 38.963028] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.968190] ? __save_stack_trace+0x61/0xd0 [ 38.972478] ? get_signal+0x73f/0x16d0 [ 38.976341] ? save_stack_trace+0x16/0x20 [ 38.980461] ? __lock_acquire+0x20fd/0x4620 [ 38.984752] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.989909] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.995074] ? save_stack_trace+0x16/0x20 [ 38.999200] ? __lock_acquire+0x20fd/0x4620 [ 39.003497] ? osq_unlock+0x350/0x350 [ 39.007267] ? save_stack_trace+0x16/0x20 [ 39.011394] ? check_noncircular+0x20/0x20 [ 39.015595] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 39.020752] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 39.025912] ? find_held_lock+0x39/0x1d0 [ 39.029943] ? lock_downgrade+0x990/0x990 [ 39.034093] ? check_noncircular+0x20/0x20 [ 39.038296] lock_acquire+0x1d5/0x580 [ 39.042066] ? exit_pi_state_list+0x369/0x7a0 [ 39.046535] ? lock_release+0xd70/0xd70 [ 39.050474] ? do_raw_spin_trylock+0x190/0x190 [ 39.055027] ? find_held_lock+0x39/0x1d0 [ 39.059065] _raw_spin_lock_irq+0x5e/0x80 [ 39.063177] ? exit_pi_state_list+0x369/0x7a0 [ 39.067641] exit_pi_state_list+0x369/0x7a0 [ 39.071946] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 39.077974] ? lock_release+0xd70/0xd70 [ 39.081915] ? check_same_owner+0x320/0x320 [ 39.086207] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 39.091277] ? __might_sleep+0x95/0x190 [ 39.095225] ? __might_fault+0x188/0x1d0 [ 39.099254] ? do_raw_spin_trylock+0x190/0x190 [ 39.103804] mm_release+0x46d/0x590 [ 39.107395] ? do_raw_spin_trylock+0x190/0x190 [ 39.111953] ? mm_access+0x140/0x140 [ 39.115647] ? _raw_spin_unlock_irq+0x27/0x70 [ 39.120127] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 39.125130] ? trace_hardirqs_on+0xd/0x10 [ 39.129258] ? _raw_spin_unlock_irq+0x27/0x70 [ 39.133721] ? acct_collect+0x637/0x800 [ 39.137662] do_exit+0x481/0x1af0 [ 39.141085] ? __might_sleep+0x95/0x190 [ 39.145036] ? mm_update_next_owner+0x930/0x930 [ 39.149680] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 39.155018] ? memset+0x31/0x40 [ 39.158275] ? get_futex_value_locked+0xc3/0xf0 [ 39.162911] ? futex_wait_setup+0x22e/0x3d0 [ 39.167200] ? futex_wake+0x680/0x680 [ 39.170970] ? fault_in_user_writeable+0x90/0x90 [ 39.175697] ? check_noncircular+0x20/0x20 [ 39.179899] ? futex_wake+0x32d/0x680 [ 39.183664] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 39.188729] ? futex_wait+0x69e/0x990 [ 39.192505] ? do_raw_spin_trylock+0x190/0x190 [ 39.197068] ? futex_wait_setup+0x3d0/0x3d0 [ 39.201366] ? find_held_lock+0x39/0x1d0 [ 39.205395] ? lock_downgrade+0x990/0x990 [ 39.209508] ? recalc_sigpending_tsk+0x117/0x150 [ 39.214234] ? recalc_sigpending+0x103/0x160 [ 39.218613] ? recalc_sigpending_tsk+0x150/0x150 [ 39.223335] ? get_signal+0x2b2/0x16d0 [ 39.227200] do_group_exit+0x149/0x400 [ 39.231060] ? __lock_is_held+0xbc/0x140 [ 39.235093] ? SyS_exit+0x30/0x30 [ 39.238516] ? _raw_spin_unlock_irq+0x27/0x70 [ 39.242989] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 39.247986] get_signal+0x73f/0x16d0 [ 39.251684] ? ptrace_notify+0x130/0x130 [ 39.255721] ? depot_save_stack+0x12c/0x490 [ 39.260017] ? putname+0xee/0x130 [ 39.263443] ? save_stack+0xa3/0xd0 [ 39.267043] ? save_stack_trace+0x16/0x20 [ 39.271169] ? save_stack+0x43/0xd0 [ 39.274767] ? kasan_slab_free+0x71/0xc0 [ 39.278798] ? kmem_cache_free+0x77/0x280 [ 39.282920] ? putname+0xee/0x130 [ 39.286343] ? do_sys_open+0x31b/0x6d0 [ 39.290195] ? compat_SyS_open+0x2a/0x40 [ 39.294230] ? do_fast_syscall_32+0x3f2/0xf05 [ 39.298700] ? find_held_lock+0x39/0x1d0 [ 39.302733] do_signal+0x94/0x1ee0 [ 39.306241] ? lock_downgrade+0x990/0x990 [ 39.310358] ? restore_nameidata+0x142/0x180 [ 39.314746] ? setup_sigcontext+0x7d0/0x7d0 [ 39.319078] ? __lock_is_held+0xbc/0x140 [ 39.323116] ? rcu_pm_notify+0xc0/0xc0 [ 39.326976] ? putname+0xee/0x130 [ 39.330396] ? putname+0xee/0x130 [ 39.333822] ? rcu_read_lock_sched_held+0x108/0x120 [ 39.338818] ? __compat_get_timespec+0xd9/0x120 [ 39.343468] ? exit_to_usermode_loop+0x8c/0x310 [ 39.348109] exit_to_usermode_loop+0x214/0x310 [ 39.352657] ? filp_open+0x70/0x70 [ 39.356163] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 39.361664] ? do_fast_syscall_32+0x158/0xf05 [ 39.366148] do_fast_syscall_32+0x83e/0xf05 [ 39.370446] ? do_int80_syscall_32+0x940/0x940 [ 39.374998] ? lockdep_sys_exit+0x47/0xf0 [ 39.379117] ? syscall_return_slowpath+0x2b3/0x510 [ 39.384014] ? finish_task_switch+0x1aa/0x740 [ 39.388483] ? sysret32_from_system_call+0x5/0x3b [ 39.393293] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 39.398103] entry_SYSENTER_compat+0x51/0x60 [ 39.402477] RIP: 0023:0xf7fe0c79 [ 39.405806] RSP: 002b:00000000f7f9a12c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0 [ 39.413478] RAX: 0000000000000000 RBX: 00000000081280f8 RCX: 0000000000000000 [ 39.420713] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 39.427964] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 39.435198] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 39.442432] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 39.449671] [ 39.451265] Allocated by task 4453: [ 39.454861] save_stack_trace+0x16/0x20 [ 39.461674] save_stack+0x43/0xd0 [ 39.465094] kasan_kmalloc+0xad/0xe0 [ 39.468776] kmem_cache_alloc_trace+0x136/0x750 [ 39.473415] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 39.478482] futex_requeue+0x1887/0x2370 [ 39.482847] do_futex+0x7f5/0x20d0 [ 39.486354] compat_SyS_futex+0x27f/0x380 [ 39.490469] do_fast_syscall_32+0x3f2/0xf05 [ 39.494755] entry_SYSENTER_compat+0x51/0x60 [ 39.499123] [ 39.500715] Freed by task 4426: [ 39.503959] save_stack_trace+0x16/0x20 [ 39.507897] save_stack+0x43/0xd0 [ 39.511321] kasan_slab_free+0x71/0xc0 [ 39.515179] kfree+0xca/0x250 [ 39.518250] put_pi_state+0x3f4/0x560 [ 39.522017] unqueue_me_pi+0x4a/0xc0 [ 39.525701] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 39.531461] do_futex+0x825/0x20d0 [ 39.534965] compat_SyS_futex+0x27f/0x380 [ 39.539080] do_fast_syscall_32+0x3f2/0xf05 [ 39.543366] entry_SYSENTER_compat+0x51/0x60 [ 39.547733] [ 39.549325] The buggy address belongs to the object at ffff8801c51adbc0 [ 39.549325] which belongs to the cache kmalloc-256 of size 256 [ 39.561946] The buggy address is located 40 bytes inside of [ 39.561946] 256-byte region [ffff8801c51adbc0, ffff8801c51adcc0) [ 39.573694] The buggy address belongs to the page: [ 39.578588] page:ffffea0007146b40 count:1 mapcount:0 mapping:ffff8801c51ad080 index:0x0 [ 39.586692] flags: 0x200000000000100(slab) [ 39.590892] raw: 0200000000000100 ffff8801c51ad080 0000000000000000 000000010000000c [ 39.598738] raw: ffffea000715b460 ffffea0007133fe0 ffff8801dac007c0 0000000000000000 [ 39.606581] page dumped because: kasan: bad access detected [ 39.612253] [ 39.613850] Memory state around the buggy address: [ 39.618748] ffff8801c51ada80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 39.626072] ffff8801c51adb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 39.633394] >ffff8801c51adb80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 39.640714] ^ [ 39.647430] ffff8801c51adc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 39.654911] ffff8801c51adc80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 39.662231] ================================================================== [ 39.669551] Disabling lock debugging due to kernel taint [ 39.674965] Kernel panic - not syncing: panic_on_warn set ... [ 39.674965] [ 39.682292] CPU: 0 PID: 4435 Comm: syz-executor2 Tainted: G B 4.14.0-rc3+ #24 [ 39.690661] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 39.699979] Call Trace: [ 39.702537] dump_stack+0x194/0x257 [ 39.706131] ? arch_local_irq_restore+0x53/0x53 [ 39.710768] ? vprintk_default+0x28/0x30 [ 39.714800] ? __lock_acquire+0x3ff0/0x4620 [ 39.719088] panic+0x1e4/0x417 [ 39.722247] ? __warn+0x1d9/0x1d9 [ 39.725670] ? __lock_acquire+0x407b/0x4620 [ 39.729960] kasan_end_report+0x50/0x50 [ 39.733901] kasan_report+0x144/0x340 [ 39.737666] __asan_report_load8_noabort+0x14/0x20 [ 39.742560] __lock_acquire+0x407b/0x4620 [ 39.746672] ? unwind_dump+0x4c0/0x4c0 [ 39.750623] ? __kernel_text_address+0xd/0x40 [ 39.755085] ? unwind_get_return_address+0x61/0xa0 [ 39.759982] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 39.765139] ? __save_stack_trace+0x61/0xd0 [ 39.769425] ? get_signal+0x73f/0x16d0 [ 39.773277] ? save_stack_trace+0x16/0x20 [ 39.777391] ? __lock_acquire+0x20fd/0x4620 [ 39.781679] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 39.786837] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 39.791993] ? save_stack_trace+0x16/0x20 [ 39.796118] ? __lock_acquire+0x20fd/0x4620 [ 39.800405] ? osq_unlock+0x350/0x350 [ 39.804168] ? save_stack_trace+0x16/0x20 [ 39.808285] ? check_noncircular+0x20/0x20 [ 39.812488] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 39.817644] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 39.822802] ? find_held_lock+0x39/0x1d0 [ 39.826832] ? lock_downgrade+0x990/0x990 [ 39.830945] ? check_noncircular+0x20/0x20 [ 39.835146] lock_acquire+0x1d5/0x580 [ 39.838914] ? exit_pi_state_list+0x369/0x7a0 [ 39.843374] ? lock_release+0xd70/0xd70 [ 39.847311] ? do_raw_spin_trylock+0x190/0x190 [ 39.851855] ? find_held_lock+0x39/0x1d0 [ 39.855889] _raw_spin_lock_irq+0x5e/0x80 [ 39.859999] ? exit_pi_state_list+0x369/0x7a0 [ 39.864463] exit_pi_state_list+0x369/0x7a0