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-2,10.128.15.202' (ECDSA) to the list of known hosts. 2017/10/01 05:48:27 parsed 1 programs 2017/10/01 05:48:27 executed programs: 0 syzkaller login: [ 29.324678] ================================================================== [ 29.332053] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 29.338683] Read of size 8 at addr ffff8801cc4c5aa8 by task syz-executor5/3435 [ 29.346004] [ 29.347600] CPU: 1 PID: 3435 Comm: syz-executor5 Not tainted 4.14.0-rc2-mm1+ #11 [ 29.355094] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.364412] Call Trace: [ 29.366963] dump_stack+0x194/0x257 [ 29.370553] ? arch_local_irq_restore+0x53/0x53 [ 29.375185] ? show_regs_print_info+0x65/0x65 [ 29.379643] ? __kernel_text_address+0xd/0x40 [ 29.384102] ? __lock_acquire+0x407b/0x4620 [ 29.388389] print_address_description+0x73/0x250 [ 29.393195] ? __lock_acquire+0x407b/0x4620 [ 29.397481] kasan_report+0x25b/0x340 [ 29.401244] __asan_report_load8_noabort+0x14/0x20 [ 29.406134] __lock_acquire+0x407b/0x4620 [ 29.410246] ? unwind_dump+0x4c0/0x4c0 [ 29.414093] ? __unwind_start+0x169/0x330 [ 29.418205] ? __kernel_text_address+0xd/0x40 [ 29.422662] ? unwind_get_return_address+0x61/0xa0 [ 29.427557] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 29.432710] ? unwind_get_return_address+0x61/0xa0 [ 29.437603] ? __save_stack_trace+0x61/0xd0 [ 29.441888] ? get_signal+0x73f/0x16d0 [ 29.445737] ? save_stack_trace+0x16/0x20 [ 29.449848] ? __lock_acquire+0x20fd/0x4620 [ 29.454133] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 29.459289] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 29.464441] ? save_stack_trace+0x16/0x20 [ 29.468551] ? __lock_acquire+0x20fd/0x4620 [ 29.472835] ? osq_unlock+0x350/0x350 [ 29.476597] ? save_stack_trace+0x16/0x20 [ 29.480708] ? lock_release+0xd70/0xd70 [ 29.484647] ? check_noncircular+0x20/0x20 [ 29.488845] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 29.494002] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 29.499156] ? find_held_lock+0x39/0x1d0 [ 29.503181] ? lock_downgrade+0x990/0x990 [ 29.507294] ? check_noncircular+0x20/0x20 [ 29.511493] lock_acquire+0x1d5/0x580 [ 29.515258] ? exit_pi_state_list+0x369/0x7a0 [ 29.519717] ? lock_release+0xd70/0xd70 [ 29.523653] ? do_raw_spin_trylock+0x190/0x190 [ 29.528198] ? find_held_lock+0x39/0x1d0 [ 29.532228] _raw_spin_lock_irq+0x5e/0x80 [ 29.536339] ? exit_pi_state_list+0x369/0x7a0 [ 29.540797] exit_pi_state_list+0x369/0x7a0 [ 29.545086] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 29.551108] ? lock_release+0xd70/0xd70 [ 29.555045] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 29.560900] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 29.565967] ? __might_sleep+0x95/0x190 [ 29.569907] ? __might_fault+0x188/0x1d0 [ 29.573932] ? do_raw_spin_trylock+0x190/0x190 [ 29.578481] mm_release+0x46d/0x590 [ 29.582069] ? do_raw_spin_trylock+0x190/0x190 [ 29.586614] ? mm_access+0x140/0x140 [ 29.590290] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.594749] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 29.599729] ? trace_hardirqs_on+0xd/0x10 [ 29.603839] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.608297] ? acct_collect+0x637/0x800 [ 29.612238] do_exit+0x481/0x1b00 [ 29.615655] ? mm_update_next_owner+0x930/0x930 [ 29.620288] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 29.626137] ? find_held_lock+0x39/0x1d0 [ 29.630164] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 29.635492] ? check_noncircular+0x20/0x20 [ 29.639692] ? fault_in_user_writeable+0x90/0x90 [ 29.644410] ? futex_wake+0x680/0x680 [ 29.648193] ? find_held_lock+0x39/0x1d0 [ 29.652220] ? lock_downgrade+0x990/0x990 [ 29.656331] ? recalc_sigpending_tsk+0x117/0x150 [ 29.661051] ? recalc_sigpending+0x103/0x160 [ 29.665423] ? recalc_sigpending_tsk+0x150/0x150 [ 29.670141] ? get_signal+0x2b2/0x16d0 [ 29.673996] do_group_exit+0x149/0x400 [ 29.677846] ? __lock_is_held+0xbc/0x140 [ 29.681869] ? SyS_exit+0x30/0x30 [ 29.685285] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.689745] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 29.694726] get_signal+0x73f/0x16d0 [ 29.698405] ? ptrace_notify+0x130/0x130 [ 29.702431] ? vma_wants_writenotify+0x3b0/0x3b0 [ 29.707154] ? exit_robust_list+0x240/0x240 [ 29.711442] ? lock_downgrade+0x990/0x990 [ 29.715551] ? SyS_brk+0x6f0/0x6f0 [ 29.719057] do_signal+0x94/0x1ee0 [ 29.722564] ? arch_get_unmapped_area+0x750/0x750 [ 29.727366] ? lock_acquire+0x1d5/0x580 [ 29.731304] ? find_held_lock+0x39/0x1d0 [ 29.735330] ? setup_sigcontext+0x7d0/0x7d0 [ 29.739616] ? lock_downgrade+0x990/0x990 [ 29.743730] ? down_write+0x120/0x120 [ 29.747502] ? lock_release+0xd70/0xd70 [ 29.751443] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 29.757292] ? vm_mmap_pgoff+0x1fc/0x280 [ 29.761318] ? exit_to_usermode_loop+0x8c/0x310 [ 29.765957] exit_to_usermode_loop+0x214/0x310 [ 29.770502] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 29.776003] ? kasan_check_write+0x14/0x20 [ 29.780203] syscall_return_slowpath+0x42f/0x510 [ 29.784922] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 29.789904] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 29.794798] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 29.799776] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 29.804497] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 29.809219] RIP: 0033:0x4520a9 [ 29.812372] RSP: 002b:00007f559ad42cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 29.820043] RAX: fffffffffffffe00 RBX: 0000000000718028 RCX: 00000000004520a9 [ 29.827277] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718028 [ 29.834523] RBP: 0000000000718000 R08: 0000000000000000 R09: 0000000000000000 [ 29.841757] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 29.848992] R13: 00007ffd6a73e4df R14: 00007f559ad439c0 R15: 0000000000000000 [ 29.856231] [ 29.857827] Allocated by task 3462: [ 29.861418] save_stack_trace+0x16/0x20 [ 29.865354] save_stack+0x43/0xd0 [ 29.868768] kasan_kmalloc+0xad/0xe0 [ 29.872444] kmem_cache_alloc_trace+0x136/0x750 [ 29.877076] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 29.882143] futex_requeue+0x1887/0x2370 [ 29.886165] do_futex+0x7f5/0x20d0 [ 29.889669] SyS_futex+0x260/0x390 [ 29.893174] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 29.897888] [ 29.899478] Freed by task 3448: [ 29.902720] save_stack_trace+0x16/0x20 [ 29.906656] save_stack+0x43/0xd0 [ 29.910071] kasan_slab_free+0x71/0xc0 [ 29.913918] kfree+0xca/0x250 [ 29.916985] put_pi_state+0x3f4/0x560 [ 29.920749] unqueue_me_pi+0x4a/0xc0 [ 29.924425] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 29.930184] do_futex+0x825/0x20d0 [ 29.933688] SyS_futex+0x260/0x390 [ 29.937191] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 29.941918] [ 29.943516] The buggy address belongs to the object at ffff8801cc4c5a80 [ 29.943516] which belongs to the cache kmalloc-256 of size 256 [ 29.956138] The buggy address is located 40 bytes inside of [ 29.956138] 256-byte region [ffff8801cc4c5a80, ffff8801cc4c5b80) [ 29.967897] The buggy address belongs to the page: [ 29.972794] page:ffffea0007313140 count:1 mapcount:0 mapping:ffff8801cc4c5080 index:0x0 [ 29.980902] flags: 0x200000000000100(slab) [ 29.985101] raw: 0200000000000100 ffff8801cc4c5080 0000000000000000 000000010000000c [ 29.992947] raw: ffffea0007303f60 ffffea000734cde0 ffff8801dac007c0 0000000000000000 [ 30.000788] page dumped because: kasan: bad access detected [ 30.006461] [ 30.008053] Memory state around the buggy address: [ 30.012944] ffff8801cc4c5980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.020266] ffff8801cc4c5a00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 30.027588] >ffff8801cc4c5a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.034907] ^ [ 30.039538] ffff8801cc4c5b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 30.046863] ffff8801cc4c5b80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 30.054192] ================================================================== [ 30.061514] Disabling lock debugging due to kernel taint [ 30.066927] Kernel panic - not syncing: panic_on_warn set ... [ 30.066927] [ 30.074251] CPU: 1 PID: 3435 Comm: syz-executor5 Tainted: G B 4.14.0-rc2-mm1+ #11 [ 30.082961] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.092277] Call Trace: [ 30.094830] dump_stack+0x194/0x257 [ 30.098422] ? arch_local_irq_restore+0x53/0x53 [ 30.103057] ? vprintk_default+0x28/0x30 [ 30.107082] ? __lock_acquire+0x4060/0x4620 [ 30.111369] panic+0x1e4/0x41c [ 30.114529] ? refcount_error_report+0x214/0x214 [ 30.119251] ? __lock_acquire+0x407b/0x4620 [ 30.123536] kasan_end_report+0x50/0x50 [ 30.127472] kasan_report+0x144/0x340 [ 30.131238] __asan_report_load8_noabort+0x14/0x20 [ 30.136132] __lock_acquire+0x407b/0x4620 [ 30.140245] ? unwind_dump+0x4c0/0x4c0 [ 30.144094] ? __unwind_start+0x169/0x330 [ 30.148205] ? __kernel_text_address+0xd/0x40 [ 30.152664] ? unwind_get_return_address+0x61/0xa0 [ 30.157559] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 30.162711] ? unwind_get_return_address+0x61/0xa0 [ 30.167603] ? __save_stack_trace+0x61/0xd0 [ 30.171887] ? get_signal+0x73f/0x16d0 [ 30.175737] ? save_stack_trace+0x16/0x20 [ 30.179846] ? __lock_acquire+0x20fd/0x4620 [ 30.184132] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 30.189287] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 30.194439] ? save_stack_trace+0x16/0x20 [ 30.198549] ? __lock_acquire+0x20fd/0x4620 [ 30.202832] ? osq_unlock+0x350/0x350 [ 30.206594] ? save_stack_trace+0x16/0x20 [ 30.210707] ? lock_release+0xd70/0xd70 [ 30.214645] ? check_noncircular+0x20/0x20 [ 30.218843] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 30.223996] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 30.229154] ? find_held_lock+0x39/0x1d0 [ 30.233181] ? lock_downgrade+0x990/0x990 [ 30.237292] ? check_noncircular+0x20/0x20 [ 30.241490] lock_acquire+0x1d5/0x580 [ 30.245255] ? exit_pi_state_list+0x369/0x7a0 [ 30.249715] ? lock_release+0xd70/0xd70 [ 30.253651] ? do_raw_spin_trylock+0x190/0x190 [ 30.258197] ? find_held_lock+0x39/0x1d0 [ 30.262226] _raw_spin_lock_irq+0x5e/0x80 [ 30.266336] ? exit_pi_state_list+0x369/0x7a0 [ 30.270793] exit_pi_state_list+0x369/0x7a0 [ 30.275080] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 30.281102] ? lock_release+0xd70/0xd70 [ 30.285041] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 30.290887] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 30.295959] ? __might_sleep+0x95/0x190 [ 30.299897] ? __might_fault+0x188/0x1d0 [ 30.303922] ? do_raw_spin_trylock+0x190/0x190 [ 30.308469] mm_release+0x46d/0x590 [ 30.312058] ? do_raw_spin_trylock+0x190/0x190 [ 30.316602] ? mm_access+0x140/0x140 [ 30.320281] ? _raw_spin_unlock_irq+0x27/0x70