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-5,10.128.0.56' (ECDSA) to the list of known hosts. 2017/10/01 05:59:05 parsed 1 programs 2017/10/01 05:59:05 executed programs: 0 syzkaller login: [ 33.085457] ================================================================== [ 33.092839] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 33.099469] Read of size 8 at addr ffff8801ceca6668 by task syz-executor0/3007 [ 33.106787] [ 33.108382] CPU: 1 PID: 3007 Comm: syz-executor0 Not tainted 4.14.0-rc2-next-20170929+ #32 [ 33.116743] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.126058] Call Trace: [ 33.128612] dump_stack+0x194/0x257 [ 33.132202] ? arch_local_irq_restore+0x53/0x53 [ 33.136831] ? show_regs_print_info+0x65/0x65 [ 33.141292] ? __kernel_text_address+0xd/0x40 [ 33.145751] ? __lock_acquire+0x407b/0x4620 [ 33.150037] print_address_description+0x73/0x250 [ 33.154843] ? __lock_acquire+0x407b/0x4620 [ 33.159129] kasan_report+0x25b/0x340 [ 33.162893] __asan_report_load8_noabort+0x14/0x20 [ 33.167783] __lock_acquire+0x407b/0x4620 [ 33.171903] ? unwind_dump+0x4c0/0x4c0 [ 33.175750] ? __unwind_start+0x169/0x330 [ 33.179860] ? __kernel_text_address+0xd/0x40 [ 33.184317] ? unwind_get_return_address+0x61/0xa0 [ 33.189214] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.194367] ? unwind_get_return_address+0x61/0xa0 [ 33.199259] ? __save_stack_trace+0x61/0xd0 [ 33.203546] ? get_signal+0x73f/0x16d0 [ 33.207399] ? save_stack_trace+0x16/0x20 [ 33.211510] ? __lock_acquire+0x20fd/0x4620 [ 33.215797] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.220951] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.226101] ? save_stack_trace+0x16/0x20 [ 33.230214] ? __lock_acquire+0x20fd/0x4620 [ 33.234496] ? osq_unlock+0x350/0x350 [ 33.238257] ? save_stack_trace+0x16/0x20 [ 33.242371] ? lock_release+0xd70/0xd70 [ 33.246308] ? check_noncircular+0x20/0x20 [ 33.250505] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.255659] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.260816] ? find_held_lock+0x39/0x1d0 [ 33.264841] ? lock_downgrade+0x990/0x990 [ 33.268951] ? check_noncircular+0x20/0x20 [ 33.273157] lock_acquire+0x1d5/0x580 [ 33.276925] ? exit_pi_state_list+0x369/0x7a0 [ 33.281385] ? lock_release+0xd70/0xd70 [ 33.285321] ? do_raw_spin_trylock+0x190/0x190 [ 33.289865] ? find_held_lock+0x39/0x1d0 [ 33.293897] _raw_spin_lock_irq+0x5e/0x80 [ 33.298009] ? exit_pi_state_list+0x369/0x7a0 [ 33.302469] exit_pi_state_list+0x369/0x7a0 [ 33.306759] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 33.312891] ? lock_release+0xd70/0xd70 [ 33.316829] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 33.322674] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 33.327742] ? __might_sleep+0x95/0x190 [ 33.331679] ? __might_fault+0x188/0x1d0 [ 33.335704] ? do_raw_spin_trylock+0x190/0x190 [ 33.340250] mm_release+0x46d/0x590 [ 33.343837] ? do_raw_spin_trylock+0x190/0x190 [ 33.348382] ? mm_access+0x140/0x140 [ 33.352056] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.356514] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.361497] ? trace_hardirqs_on+0xd/0x10 [ 33.365609] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.370065] ? acct_collect+0x637/0x800 [ 33.374001] do_exit+0x481/0x1b00 [ 33.377419] ? mm_update_next_owner+0x930/0x930 [ 33.382051] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 33.387897] ? find_held_lock+0x39/0x1d0 [ 33.391925] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 33.397251] ? check_noncircular+0x20/0x20 [ 33.401452] ? fault_in_user_writeable+0x90/0x90 [ 33.406172] ? futex_wake+0x680/0x680 [ 33.409946] ? find_held_lock+0x39/0x1d0 [ 33.413974] ? lock_downgrade+0x990/0x990 [ 33.418084] ? recalc_sigpending_tsk+0x117/0x150 [ 33.422801] ? recalc_sigpending+0x103/0x160 [ 33.427170] ? recalc_sigpending_tsk+0x150/0x150 [ 33.431889] ? get_signal+0x2b2/0x16d0 [ 33.435740] do_group_exit+0x149/0x400 [ 33.439591] ? __lock_is_held+0xbc/0x140 [ 33.443613] ? SyS_exit+0x30/0x30 [ 33.447031] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.451489] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.456466] get_signal+0x73f/0x16d0 [ 33.460143] ? ptrace_notify+0x130/0x130 [ 33.464167] ? __schedule+0x8f0/0x2070 [ 33.468019] ? exit_robust_list+0x240/0x240 [ 33.472303] ? lock_downgrade+0x990/0x990 [ 33.476413] ? SyS_brk+0x6f0/0x6f0 [ 33.479917] do_signal+0x94/0x1ee0 [ 33.483420] ? arch_get_unmapped_area+0x750/0x750 [ 33.488225] ? lock_acquire+0x1d5/0x580 [ 33.492162] ? find_held_lock+0x39/0x1d0 [ 33.496187] ? setup_sigcontext+0x7d0/0x7d0 [ 33.500472] ? lock_downgrade+0x990/0x990 [ 33.504585] ? down_write+0x120/0x120 [ 33.508347] ? lock_release+0xd70/0xd70 [ 33.512287] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 33.518134] ? vm_mmap_pgoff+0x1fc/0x280 [ 33.522158] ? exit_to_usermode_loop+0x8c/0x310 [ 33.526793] exit_to_usermode_loop+0x214/0x310 [ 33.531338] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 33.536838] ? kasan_check_write+0x14/0x20 [ 33.541037] syscall_return_slowpath+0x42f/0x510 [ 33.545756] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 33.550736] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 33.555628] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.560610] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 33.565331] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 33.570049] RIP: 0033:0x4520a9 [ 33.573201] RSP: 002b:00007f3a74c5bcf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 33.580870] RAX: fffffffffffffe00 RBX: 0000000000718028 RCX: 00000000004520a9 [ 33.588102] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718028 [ 33.595334] RBP: 0000000000718000 R08: 0000000000000000 R09: 0000000000000000 [ 33.602567] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 33.609800] R13: 00007ffc167bebaf R14: 00007f3a74c5c9c0 R15: 0000000000000000 [ 33.617039] [ 33.618630] Allocated by task 3033: [ 33.622220] save_stack_trace+0x16/0x20 [ 33.626156] save_stack+0x43/0xd0 [ 33.629568] kasan_kmalloc+0xad/0xe0 [ 33.633247] kmem_cache_alloc_trace+0x136/0x750 [ 33.637878] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 33.642943] futex_requeue+0x1887/0x2370 [ 33.646964] do_futex+0x7f5/0x20d0 [ 33.650465] SyS_futex+0x260/0x390 [ 33.653968] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 33.658682] [ 33.660272] Freed by task 3023: [ 33.663513] save_stack_trace+0x16/0x20 [ 33.667463] save_stack+0x43/0xd0 [ 33.670878] kasan_slab_free+0x71/0xc0 [ 33.674727] kfree+0xca/0x250 [ 33.677794] put_pi_state+0x3f4/0x560 [ 33.681556] unqueue_me_pi+0x4a/0xc0 [ 33.685232] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 33.690989] do_futex+0x825/0x20d0 [ 33.694492] SyS_futex+0x260/0x390 [ 33.697993] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 33.702708] [ 33.704299] The buggy address belongs to the object at ffff8801ceca6640 [ 33.704299] which belongs to the cache kmalloc-256 of size 256 [ 33.716916] The buggy address is located 40 bytes inside of [ 33.716916] 256-byte region [ffff8801ceca6640, ffff8801ceca6740) [ 33.728662] The buggy address belongs to the page: [ 33.733554] page:ffffea00073b2980 count:1 mapcount:0 mapping:ffff8801ceca6000 index:0xffff8801ceca6500 [ 33.742957] flags: 0x200000000000100(slab) [ 33.747157] raw: 0200000000000100 ffff8801ceca6000 ffff8801ceca6500 000000010000000a [ 33.754999] raw: ffffea000739dce0 ffffea0007397520 ffff8801dac007c0 0000000000000000 [ 33.762838] page dumped because: kasan: bad access detected [ 33.768512] [ 33.770102] Memory state around the buggy address: [ 33.774993] ffff8801ceca6500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.782313] ffff8801ceca6580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.789631] >ffff8801ceca6600: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 33.796951] ^ [ 33.803662] ffff8801ceca6680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.810981] ffff8801ceca6700: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 33.818302] ================================================================== [ 33.825621] Disabling lock debugging due to kernel taint [ 33.831032] Kernel panic - not syncing: panic_on_warn set ... [ 33.831032] [ 33.838357] CPU: 1 PID: 3007 Comm: syz-executor0 Tainted: G B 4.14.0-rc2-next-20170929+ #32 [ 33.847933] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.857248] Call Trace: [ 33.859798] dump_stack+0x194/0x257 [ 33.863389] ? arch_local_irq_restore+0x53/0x53 [ 33.868022] ? vprintk_default+0x28/0x30 [ 33.872048] ? __lock_acquire+0x4000/0x4620 [ 33.876335] panic+0x1e4/0x41c [ 33.879490] ? refcount_error_report+0x214/0x214 [ 33.884213] ? __lock_acquire+0x407b/0x4620 [ 33.888497] kasan_end_report+0x50/0x50 [ 33.892437] kasan_report+0x144/0x340 [ 33.896203] __asan_report_load8_noabort+0x14/0x20 [ 33.901094] __lock_acquire+0x407b/0x4620 [ 33.905204] ? unwind_dump+0x4c0/0x4c0 [ 33.909052] ? __unwind_start+0x169/0x330 [ 33.913163] ? __kernel_text_address+0xd/0x40 [ 33.917619] ? unwind_get_return_address+0x61/0xa0 [ 33.922517] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.927667] ? unwind_get_return_address+0x61/0xa0 [ 33.932559] ? __save_stack_trace+0x61/0xd0 [ 33.936843] ? get_signal+0x73f/0x16d0 [ 33.940694] ? save_stack_trace+0x16/0x20 [ 33.944806] ? __lock_acquire+0x20fd/0x4620 [ 33.949090] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.954247] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.959396] ? save_stack_trace+0x16/0x20 [ 33.963507] ? __lock_acquire+0x20fd/0x4620 [ 33.967790] ? osq_unlock+0x350/0x350 [ 33.971551] ? save_stack_trace+0x16/0x20 [ 33.975660] ? lock_release+0xd70/0xd70 [ 33.979599] ? check_noncircular+0x20/0x20 [ 33.983798] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.988954] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.994108] ? find_held_lock+0x39/0x1d0 [ 33.998133] ? lock_downgrade+0x990/0x990 [ 34.002243] ? check_noncircular+0x20/0x20 [ 34.006440] lock_acquire+0x1d5/0x580 [ 34.010204] ? exit_pi_state_list+0x369/0x7a0 [ 34.014665] ? lock_release+0xd70/0xd70 [ 34.018601] ? do_raw_spin_trylock+0x190/0x190 [ 34.023143] ? find_held_lock+0x39/0x1d0 [ 34.027172] _raw_spin_lock_irq+0x5e/0x80 [ 34.031280] ? exit_pi_state_list+0x369/0x7a0 [ 34.035736] exit_pi_state_list+0x369/0x7a0 [ 34.040023] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 34.046046] ? lock_release+0xd70/0xd70 [ 34.049983] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 34.055831] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 34.060897] ? __might_sleep+0x95/0x190 [ 34.064835] ? __might_fault+0x188/0x1d0 [ 34.068858] ? do_raw_spin_trylock+0x190/0x190 [ 34.073407] mm_release+0x46d/0x590 [ 34.076996] ? do_raw_spin_trylock+0x190/0x190 [ 34.081541] ? mm_access+0x140/0x140 [ 34.085218] ? _raw_spin_unlock_irq+0x27/0x70