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-6,10.128.0.24' (ECDSA) to the list of known hosts. 2017/09/30 22:32:52 parsed 1 programs 2017/09/30 22:32:52 executed programs: 0 syzkaller login: [ 33.459982] ================================================================== [ 33.467399] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 33.474029] Read of size 8 at addr ffff8801cb326728 by task syz-executor2/4180 [ 33.481353] [ 33.482950] CPU: 0 PID: 4180 Comm: syz-executor2 Not tainted 4.14.0-rc2-mm1+ #11 [ 33.490443] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.499761] Call Trace: [ 33.502313] dump_stack+0x194/0x257 [ 33.505906] ? arch_local_irq_restore+0x53/0x53 [ 33.510539] ? show_regs_print_info+0x65/0x65 [ 33.514998] ? __kernel_text_address+0xd/0x40 [ 33.519457] ? __lock_acquire+0x407b/0x4620 [ 33.523753] print_address_description+0x73/0x250 [ 33.528558] ? __lock_acquire+0x407b/0x4620 [ 33.532846] kasan_report+0x25b/0x340 [ 33.536614] __asan_report_load8_noabort+0x14/0x20 [ 33.541506] __lock_acquire+0x407b/0x4620 [ 33.545621] ? unwind_dump+0x4c0/0x4c0 [ 33.549470] ? __unwind_start+0x169/0x330 [ 33.553581] ? __kernel_text_address+0xd/0x40 [ 33.558038] ? unwind_get_return_address+0x61/0xa0 [ 33.562933] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.568084] ? unwind_get_return_address+0x61/0xa0 [ 33.572979] ? __save_stack_trace+0x61/0xd0 [ 33.577267] ? get_signal+0x73f/0x16d0 [ 33.581117] ? save_stack_trace+0x16/0x20 [ 33.585228] ? __lock_acquire+0x20fd/0x4620 [ 33.589514] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.594670] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.599822] ? save_stack_trace+0x16/0x20 [ 33.603932] ? __lock_acquire+0x20fd/0x4620 [ 33.608215] ? osq_unlock+0x350/0x350 [ 33.611977] ? save_stack_trace+0x16/0x20 [ 33.616089] ? lock_release+0xd70/0xd70 [ 33.620028] ? check_noncircular+0x20/0x20 [ 33.624226] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.629380] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.634538] ? find_held_lock+0x39/0x1d0 [ 33.638566] ? lock_downgrade+0x990/0x990 [ 33.642676] ? check_noncircular+0x20/0x20 [ 33.646875] lock_acquire+0x1d5/0x580 [ 33.650641] ? exit_pi_state_list+0x369/0x7a0 [ 33.655100] ? lock_release+0xd70/0xd70 [ 33.659038] ? do_raw_spin_trylock+0x190/0x190 [ 33.663583] ? find_held_lock+0x39/0x1d0 [ 33.667618] _raw_spin_lock_irq+0x5e/0x80 [ 33.671728] ? exit_pi_state_list+0x369/0x7a0 [ 33.676186] exit_pi_state_list+0x369/0x7a0 [ 33.680473] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 33.686493] ? lock_release+0xd70/0xd70 [ 33.690433] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 33.696281] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 33.701357] ? __might_sleep+0x95/0x190 [ 33.705298] ? __might_fault+0x188/0x1d0 [ 33.709323] ? do_raw_spin_trylock+0x190/0x190 [ 33.713892] mm_release+0x46d/0x590 [ 33.717500] ? do_raw_spin_trylock+0x190/0x190 [ 33.722058] ? mm_access+0x140/0x140 [ 33.725738] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.730204] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.735183] ? trace_hardirqs_on+0xd/0x10 [ 33.739300] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.743767] ? acct_collect+0x637/0x800 [ 33.747706] do_exit+0x481/0x1b00 [ 33.751127] ? mm_update_next_owner+0x930/0x930 [ 33.755763] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 33.761615] ? find_held_lock+0x39/0x1d0 [ 33.765645] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 33.770976] ? check_noncircular+0x20/0x20 [ 33.775175] ? fault_in_user_writeable+0x90/0x90 [ 33.779904] ? futex_wake+0x680/0x680 [ 33.783671] ? find_held_lock+0x39/0x1d0 [ 33.787700] ? lock_downgrade+0x990/0x990 [ 33.791815] ? recalc_sigpending_tsk+0x117/0x150 [ 33.796535] ? recalc_sigpending+0x103/0x160 [ 33.800906] ? recalc_sigpending_tsk+0x150/0x150 [ 33.805625] ? get_signal+0x2b2/0x16d0 [ 33.809479] do_group_exit+0x149/0x400 [ 33.813334] ? __lock_is_held+0xbc/0x140 [ 33.817359] ? SyS_exit+0x30/0x30 [ 33.820778] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.825238] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.830219] get_signal+0x73f/0x16d0 [ 33.833897] ? ptrace_notify+0x130/0x130 [ 33.837922] ? __schedule+0x8f0/0x2070 [ 33.841776] ? exit_robust_list+0x240/0x240 [ 33.846064] ? lock_downgrade+0x990/0x990 [ 33.850176] ? SyS_brk+0x6f0/0x6f0 [ 33.853684] do_signal+0x94/0x1ee0 [ 33.857191] ? arch_get_unmapped_area+0x750/0x750 [ 33.861996] ? lock_acquire+0x1d5/0x580 [ 33.865938] ? find_held_lock+0x39/0x1d0 [ 33.869965] ? setup_sigcontext+0x7d0/0x7d0 [ 33.874251] ? lock_downgrade+0x990/0x990 [ 33.878366] ? down_write+0x120/0x120 [ 33.882134] ? lock_release+0xd70/0xd70 [ 33.886075] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 33.891922] ? vm_mmap_pgoff+0x1fc/0x280 [ 33.895947] ? exit_to_usermode_loop+0x8c/0x310 [ 33.900580] exit_to_usermode_loop+0x214/0x310 [ 33.905132] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 33.910639] ? kasan_check_write+0x14/0x20 [ 33.914838] syscall_return_slowpath+0x42f/0x510 [ 33.919560] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 33.924540] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 33.929435] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.934413] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 33.939134] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 33.943855] RIP: 0033:0x4520a9 [ 33.947010] RSP: 002b:00007f410e9e6cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 33.954687] RAX: fffffffffffffe00 RBX: 0000000000718028 RCX: 00000000004520a9 [ 33.961923] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718028 [ 33.969156] RBP: 0000000000718000 R08: 0000000000000000 R09: 0000000000000000 [ 33.976389] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 33.983628] R13: 00007ffd7e0855cf R14: 00007f410e9e79c0 R15: 0000000000000000 [ 33.990871] [ 33.992464] Allocated by task 4206: [ 33.996059] save_stack_trace+0x16/0x20 [ 33.999999] save_stack+0x43/0xd0 [ 34.003421] kasan_kmalloc+0xad/0xe0 [ 34.007100] kmem_cache_alloc_trace+0x136/0x750 [ 34.011731] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 34.016801] futex_requeue+0x1887/0x2370 [ 34.020824] do_futex+0x7f5/0x20d0 [ 34.024327] SyS_futex+0x260/0x390 [ 34.027830] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 34.032548] [ 34.034140] Freed by task 4196: [ 34.037383] save_stack_trace+0x16/0x20 [ 34.041318] save_stack+0x43/0xd0 [ 34.044740] kasan_slab_free+0x71/0xc0 [ 34.048594] kfree+0xca/0x250 [ 34.051665] put_pi_state+0x3f4/0x560 [ 34.055426] unqueue_me_pi+0x4a/0xc0 [ 34.059105] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 34.064862] do_futex+0x825/0x20d0 [ 34.068363] SyS_futex+0x260/0x390 [ 34.071867] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 34.076585] [ 34.078177] The buggy address belongs to the object at ffff8801cb326700 [ 34.078177] which belongs to the cache kmalloc-256 of size 256 [ 34.090797] The buggy address is located 40 bytes inside of [ 34.090797] 256-byte region [ffff8801cb326700, ffff8801cb326800) [ 34.102546] The buggy address belongs to the page: [ 34.107438] page:ffffea00072cc980 count:1 mapcount:0 mapping:ffff8801cb3260c0 index:0xffff8801cb326e80 [ 34.116843] flags: 0x200000000000100(slab) [ 34.121042] raw: 0200000000000100 ffff8801cb3260c0 ffff8801cb326e80 0000000100000007 [ 34.128884] raw: ffff8801dac01640 ffffea00072eab60 ffff8801dac007c0 0000000000000000 [ 34.136725] page dumped because: kasan: bad access detected [ 34.142393] [ 34.143987] Memory state around the buggy address: [ 34.148881] ffff8801cb326600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 34.156201] ffff8801cb326680: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 34.163521] >ffff8801cb326700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.170841] ^ [ 34.175471] ffff8801cb326780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.182795] ffff8801cb326800: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 34.190115] ================================================================== [ 34.197433] Disabling lock debugging due to kernel taint [ 34.202846] Kernel panic - not syncing: panic_on_warn set ... [ 34.202846] [ 34.210172] CPU: 0 PID: 4180 Comm: syz-executor2 Tainted: G B 4.14.0-rc2-mm1+ #11 [ 34.218881] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.228195] Call Trace: [ 34.230748] dump_stack+0x194/0x257 [ 34.234338] ? arch_local_irq_restore+0x53/0x53 [ 34.238972] ? vprintk_default+0x28/0x30 [ 34.242999] ? __lock_acquire+0x4060/0x4620 [ 34.247290] panic+0x1e4/0x41c [ 34.250445] ? refcount_error_report+0x214/0x214 [ 34.255166] ? __lock_acquire+0x407b/0x4620 [ 34.259449] kasan_end_report+0x50/0x50 [ 34.263385] kasan_report+0x144/0x340 [ 34.267151] __asan_report_load8_noabort+0x14/0x20 [ 34.272047] __lock_acquire+0x407b/0x4620 [ 34.276163] ? unwind_dump+0x4c0/0x4c0 [ 34.280017] ? __unwind_start+0x169/0x330 [ 34.284137] ? __kernel_text_address+0xd/0x40 [ 34.288597] ? unwind_get_return_address+0x61/0xa0 [ 34.293492] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.298642] ? unwind_get_return_address+0x61/0xa0 [ 34.303535] ? __save_stack_trace+0x61/0xd0 [ 34.307821] ? get_signal+0x73f/0x16d0 [ 34.311673] ? save_stack_trace+0x16/0x20 [ 34.315787] ? __lock_acquire+0x20fd/0x4620 [ 34.320074] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.325229] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.330380] ? save_stack_trace+0x16/0x20 [ 34.334490] ? __lock_acquire+0x20fd/0x4620 [ 34.338774] ? osq_unlock+0x350/0x350 [ 34.342540] ? save_stack_trace+0x16/0x20 [ 34.346652] ? lock_release+0xd70/0xd70 [ 34.350591] ? check_noncircular+0x20/0x20 [ 34.354793] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.359946] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.365099] ? find_held_lock+0x39/0x1d0 [ 34.369127] ? lock_downgrade+0x990/0x990 [ 34.373238] ? check_noncircular+0x20/0x20 [ 34.377434] lock_acquire+0x1d5/0x580 [ 34.381199] ? exit_pi_state_list+0x369/0x7a0 [ 34.385659] ? lock_release+0xd70/0xd70 [ 34.389594] ? do_raw_spin_trylock+0x190/0x190 [ 34.394137] ? find_held_lock+0x39/0x1d0 [ 34.398165] _raw_spin_lock_irq+0x5e/0x80 [ 34.402276] ? exit_pi_state_list+0x369/0x7a0 [ 34.406734] exit_pi_state_list+0x369/0x7a0 [ 34.411027] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 34.417047] ? lock_release+0xd70/0xd70 [ 34.420986] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 34.426835] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 34.431905] ? __might_sleep+0x95/0x190 [ 34.435843] ? __might_fault+0x188/0x1d0 [ 34.439868] ? do_raw_spin_trylock+0x190/0x190 [ 34.444412] mm_release+0x46d/0x590 [ 34.448001] ? do_raw_spin_trylock+0x190/0x190 [ 34.452549] ? mm_access+0x140/0x140 [ 34.456227] ? _raw_spin_unlock_irq+0x27/0x70