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-5,10.128.0.19' (ECDSA) to the list of known hosts. 2017/10/01 10:24:00 parsed 1 programs 2017/10/01 10:24:00 executed programs: 0 2017/10/01 10:24:05 executed programs: 37 syzkaller login: [ 37.500190] ================================================================== [ 37.507581] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 37.514210] Read of size 8 at addr ffff8801cc7eab68 by task syz-executor0/3249 [ 37.521530] [ 37.523126] CPU: 0 PID: 3249 Comm: syz-executor0 Not tainted 4.14.0-rc2-mm1+ #11 [ 37.530621] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 37.539935] Call Trace: [ 37.542490] dump_stack+0x194/0x257 [ 37.546083] ? arch_local_irq_restore+0x53/0x53 [ 37.550716] ? show_regs_print_info+0x65/0x65 [ 37.555175] ? __kernel_text_address+0xd/0x40 [ 37.559636] ? __lock_acquire+0x407b/0x4620 [ 37.563923] print_address_description+0x73/0x250 [ 37.568728] ? __lock_acquire+0x407b/0x4620 [ 37.573026] kasan_report+0x25b/0x340 [ 37.576799] __asan_report_load8_noabort+0x14/0x20 [ 37.581691] __lock_acquire+0x407b/0x4620 [ 37.585803] ? unwind_dump+0x4c0/0x4c0 [ 37.589655] ? __unwind_start+0x169/0x330 [ 37.593767] ? __kernel_text_address+0xd/0x40 [ 37.598226] ? unwind_get_return_address+0x61/0xa0 [ 37.603123] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 37.608276] ? unwind_get_return_address+0x61/0xa0 [ 37.613167] ? __save_stack_trace+0x61/0xd0 [ 37.617453] ? get_signal+0x73f/0x16d0 [ 37.621305] ? save_stack_trace+0x16/0x20 [ 37.625417] ? __lock_acquire+0x20fd/0x4620 [ 37.629706] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 37.634865] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 37.640018] ? save_stack_trace+0x16/0x20 [ 37.644128] ? __lock_acquire+0x20fd/0x4620 [ 37.648415] ? osq_unlock+0x350/0x350 [ 37.652177] ? perf_trace_lock+0xf1/0x860 [ 37.656287] ? lock_release+0xd70/0xd70 [ 37.660225] ? check_noncircular+0x20/0x20 [ 37.664423] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 37.669577] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 37.674735] ? perf_trace_lock+0xf1/0x860 [ 37.678848] ? find_held_lock+0x39/0x1d0 [ 37.682875] ? lock_downgrade+0x990/0x990 [ 37.686987] ? check_noncircular+0x20/0x20 [ 37.691185] lock_acquire+0x1d5/0x580 [ 37.694950] ? exit_pi_state_list+0x369/0x7a0 [ 37.699412] ? lock_release+0xd70/0xd70 [ 37.703349] ? do_raw_spin_trylock+0x190/0x190 [ 37.707893] ? find_held_lock+0x39/0x1d0 [ 37.711924] _raw_spin_lock_irq+0x5e/0x80 [ 37.716035] ? exit_pi_state_list+0x369/0x7a0 [ 37.720494] exit_pi_state_list+0x369/0x7a0 [ 37.724783] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 37.730807] ? lock_release+0xd70/0xd70 [ 37.734747] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 37.740593] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 37.745659] ? __might_sleep+0x95/0x190 [ 37.749595] ? __might_fault+0x188/0x1d0 [ 37.753618] ? do_raw_spin_trylock+0x190/0x190 [ 37.758162] mm_release+0x46d/0x590 [ 37.761750] ? do_raw_spin_trylock+0x190/0x190 [ 37.766293] ? mm_access+0x140/0x140 [ 37.769968] ? _raw_spin_unlock_irq+0x27/0x70 [ 37.774428] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 37.779409] ? trace_hardirqs_on+0xd/0x10 [ 37.783522] ? _raw_spin_unlock_irq+0x27/0x70 [ 37.787980] ? acct_collect+0x637/0x800 [ 37.791920] do_exit+0x481/0x1b00 [ 37.795335] ? mm_update_next_owner+0x930/0x930 [ 37.799966] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 37.805815] ? find_held_lock+0x39/0x1d0 [ 37.809842] ? perf_trace_lock+0xf1/0x860 [ 37.813955] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 37.819284] ? check_noncircular+0x20/0x20 [ 37.823492] ? fault_in_user_writeable+0x90/0x90 [ 37.828213] ? futex_wake+0x680/0x680 [ 37.831977] ? find_held_lock+0x39/0x1d0 [ 37.836004] ? lock_downgrade+0x990/0x990 [ 37.840117] ? recalc_sigpending_tsk+0x117/0x150 [ 37.844835] ? recalc_sigpending+0x103/0x160 [ 37.849207] ? recalc_sigpending_tsk+0x150/0x150 [ 37.853924] ? get_signal+0x2b2/0x16d0 [ 37.857775] do_group_exit+0x149/0x400 [ 37.861625] ? __lock_is_held+0xbc/0x140 [ 37.865657] ? SyS_exit+0x30/0x30 [ 37.869073] ? _raw_spin_unlock_irq+0x27/0x70 [ 37.873532] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 37.878515] get_signal+0x73f/0x16d0 [ 37.882194] ? ptrace_notify+0x130/0x130 [ 37.886219] ? vma_wants_writenotify+0x3b0/0x3b0 [ 37.890937] ? perf_trace_lock+0xf1/0x860 [ 37.895050] ? exit_robust_list+0x240/0x240 [ 37.899335] ? lock_downgrade+0x990/0x990 [ 37.903447] ? SyS_brk+0x6f0/0x6f0 [ 37.906951] do_signal+0x94/0x1ee0 [ 37.910454] ? arch_get_unmapped_area+0x750/0x750 [ 37.915258] ? lock_acquire+0x1d5/0x580 [ 37.919196] ? find_held_lock+0x39/0x1d0 [ 37.923220] ? setup_sigcontext+0x7d0/0x7d0 [ 37.927506] ? lock_downgrade+0x990/0x990 [ 37.931622] ? down_write+0x120/0x120 [ 37.935388] ? lock_release+0xd70/0xd70 [ 37.939327] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 37.945174] ? vm_mmap_pgoff+0x1fc/0x280 [ 37.949200] ? exit_to_usermode_loop+0x8c/0x310 [ 37.953834] exit_to_usermode_loop+0x214/0x310 [ 37.958380] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 37.963881] ? kasan_check_write+0x14/0x20 [ 37.968081] syscall_return_slowpath+0x42f/0x510 [ 37.972799] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 37.977778] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 37.982671] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 37.987648] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 37.992370] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 37.997088] RIP: 0033:0x4520a9 [ 38.000242] RSP: 002b:00007f11e8835cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 38.007911] RAX: fffffffffffffe00 RBX: 0000000000718188 RCX: 00000000004520a9 [ 38.015142] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718188 [ 38.022375] RBP: 0000000000718160 R08: 0000000000000000 R09: 0000000000000000 [ 38.029608] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 38.036843] R13: 0000000000a6f7ef R14: 00007f11e88369c0 R15: 0000000000000015 [ 38.044087] [ 38.045678] Allocated by task 3250: [ 38.049266] save_stack_trace+0x16/0x20 [ 38.053199] save_stack+0x43/0xd0 [ 38.056612] kasan_kmalloc+0xad/0xe0 [ 38.060289] kmem_cache_alloc_trace+0x136/0x750 [ 38.064927] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 38.069991] futex_requeue+0x1887/0x2370 [ 38.074012] do_futex+0x7f5/0x20d0 [ 38.077515] SyS_futex+0x260/0x390 [ 38.081018] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 38.085731] [ 38.087322] Freed by task 3248: [ 38.090563] save_stack_trace+0x16/0x20 [ 38.094496] save_stack+0x43/0xd0 [ 38.097910] kasan_slab_free+0x71/0xc0 [ 38.101758] kfree+0xca/0x250 [ 38.104827] put_pi_state+0x3f4/0x560 [ 38.108589] unqueue_me_pi+0x4a/0xc0 [ 38.112266] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 38.118022] do_futex+0x825/0x20d0 [ 38.121523] SyS_futex+0x260/0x390 [ 38.125025] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 38.129740] [ 38.131332] The buggy address belongs to the object at ffff8801cc7eab40 [ 38.131332] which belongs to the cache kmalloc-256 of size 256 [ 38.143947] The buggy address is located 40 bytes inside of [ 38.143947] 256-byte region [ffff8801cc7eab40, ffff8801cc7eac40) [ 38.155696] The buggy address belongs to the page: [ 38.160587] page:ffffea000731fa80 count:1 mapcount:0 mapping:ffff8801cc7ea000 index:0x0 [ 38.168695] flags: 0x200000000000100(slab) [ 38.172894] raw: 0200000000000100 ffff8801cc7ea000 0000000000000000 000000010000000c [ 38.180734] raw: ffffea0007319320 ffffea0007302be0 ffff8801dac007c0 0000000000000000 [ 38.188574] page dumped because: kasan: bad access detected [ 38.194242] [ 38.195832] Memory state around the buggy address: [ 38.200723] ffff8801cc7eaa00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 38.208042] ffff8801cc7eaa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 38.215361] >ffff8801cc7eab00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 38.222679] ^ [ 38.229395] ffff8801cc7eab80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 38.236725] ffff8801cc7eac00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 38.244043] ================================================================== [ 38.251364] Disabling lock debugging due to kernel taint [ 38.256773] Kernel panic - not syncing: panic_on_warn set ... [ 38.256773] [ 38.264097] CPU: 0 PID: 3249 Comm: syz-executor0 Tainted: G B 4.14.0-rc2-mm1+ #11 [ 38.272807] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 38.282120] Call Trace: [ 38.284670] dump_stack+0x194/0x257 [ 38.288262] ? arch_local_irq_restore+0x53/0x53 [ 38.292893] ? vprintk_default+0x28/0x30 [ 38.296917] ? __lock_acquire+0x4060/0x4620 [ 38.301203] panic+0x1e4/0x41c [ 38.304361] ? refcount_error_report+0x214/0x214 [ 38.309083] ? __lock_acquire+0x407b/0x4620 [ 38.313365] kasan_end_report+0x50/0x50 [ 38.317300] kasan_report+0x144/0x340 [ 38.321062] __asan_report_load8_noabort+0x14/0x20 [ 38.325953] __lock_acquire+0x407b/0x4620 [ 38.330064] ? unwind_dump+0x4c0/0x4c0 [ 38.333912] ? __unwind_start+0x169/0x330 [ 38.338022] ? __kernel_text_address+0xd/0x40 [ 38.342478] ? unwind_get_return_address+0x61/0xa0 [ 38.347374] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.352526] ? unwind_get_return_address+0x61/0xa0 [ 38.357417] ? __save_stack_trace+0x61/0xd0 [ 38.361703] ? get_signal+0x73f/0x16d0 [ 38.365551] ? save_stack_trace+0x16/0x20 [ 38.369660] ? __lock_acquire+0x20fd/0x4620 [ 38.373947] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.379102] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.384253] ? save_stack_trace+0x16/0x20 [ 38.388362] ? __lock_acquire+0x20fd/0x4620 [ 38.392644] ? osq_unlock+0x350/0x350 [ 38.396409] ? perf_trace_lock+0xf1/0x860 [ 38.400519] ? lock_release+0xd70/0xd70 [ 38.404456] ? check_noncircular+0x20/0x20 [ 38.408653] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.413806] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.418957] ? perf_trace_lock+0xf1/0x860 [ 38.423069] ? find_held_lock+0x39/0x1d0 [ 38.427093] ? lock_downgrade+0x990/0x990 [ 38.431202] ? check_noncircular+0x20/0x20 [ 38.435399] lock_acquire+0x1d5/0x580 [ 38.439161] ? exit_pi_state_list+0x369/0x7a0 [ 38.443618] ? lock_release+0xd70/0xd70 [ 38.447554] ? do_raw_spin_trylock+0x190/0x190 [ 38.452096] ? find_held_lock+0x39/0x1d0 [ 38.456123] _raw_spin_lock_irq+0x5e/0x80 [ 38.460231] ? exit_pi_state_list+0x369/0x7a0 [ 38.464688] exit_pi_state_list+0x369/0x7a0 [ 38.468975] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 38.474997] ? lock_release+0xd70/0xd70 [ 38.478935] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 38.484780] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 38.489846] ? __might_sleep+0x95/0x190 [ 38.493781] ? __might_fault+0x188/0x1d0 [ 38.497805] ? do_raw_spin_trylock+0x190/0x190