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-2,10.128.0.36' (ECDSA) to the list of known hosts. 2017/09/28 04:54:03 parsed 1 programs 2017/09/28 04:54:03 executed programs: 0 syzkaller login: [ 135.606483] ================================================================== [ 135.613961] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 135.620597] Read of size 8 at addr ffff8801c6922d68 by task syz-executor7/5638 [ 135.627931] [ 135.629552] CPU: 0 PID: 5638 Comm: syz-executor7 Not tainted 4.14.0-rc2-next-20170927+ #30 [ 135.637928] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 135.647259] Call Trace: [ 135.649826] dump_stack+0x194/0x257 [ 135.653437] ? arch_local_irq_restore+0x53/0x53 [ 135.658092] ? show_regs_print_info+0x65/0x65 [ 135.662554] ? __kernel_text_address+0xd/0x40 [ 135.667026] ? __lock_acquire+0x407b/0x4620 [ 135.671329] print_address_description+0x73/0x250 [ 135.676147] ? __lock_acquire+0x407b/0x4620 [ 135.680446] kasan_report+0x25b/0x340 [ 135.684217] __asan_report_load8_noabort+0x14/0x20 [ 135.689114] __lock_acquire+0x407b/0x4620 [ 135.693230] ? unwind_dump+0x4c0/0x4c0 [ 135.697080] ? __unwind_start+0x169/0x330 [ 135.701195] ? __kernel_text_address+0xd/0x40 [ 135.705655] ? unwind_get_return_address+0x61/0xa0 [ 135.710556] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 135.715713] ? unwind_get_return_address+0x61/0xa0 [ 135.720610] ? __save_stack_trace+0x61/0xd0 [ 135.724898] ? get_signal+0x73f/0x16d0 [ 135.728753] ? save_stack_trace+0x16/0x20 [ 135.732867] ? __lock_acquire+0x20fd/0x4620 [ 135.737158] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 135.742318] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 135.747473] ? save_stack_trace+0x16/0x20 [ 135.751589] ? __lock_acquire+0x20fd/0x4620 [ 135.755876] ? osq_unlock+0x350/0x350 [ 135.759648] ? save_stack_trace+0x16/0x20 [ 135.763774] ? lock_release+0xd70/0xd70 [ 135.767714] ? check_noncircular+0x20/0x20 [ 135.771919] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 135.777076] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 135.782237] ? find_held_lock+0x39/0x1d0 [ 135.786266] ? lock_downgrade+0x990/0x990 [ 135.790379] ? check_noncircular+0x20/0x20 [ 135.794580] lock_acquire+0x1d5/0x580 [ 135.798348] ? exit_pi_state_list+0x369/0x7a0 [ 135.802810] ? lock_release+0xd70/0xd70 [ 135.806749] ? do_raw_spin_trylock+0x190/0x190 [ 135.811299] ? find_held_lock+0x39/0x1d0 [ 135.815330] _raw_spin_lock_irq+0x5e/0x80 [ 135.819457] ? exit_pi_state_list+0x369/0x7a0 [ 135.823921] exit_pi_state_list+0x369/0x7a0 [ 135.828219] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 135.834243] ? lock_release+0xd70/0xd70 [ 135.838183] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 135.844036] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 135.849113] ? __might_sleep+0x95/0x190 [ 135.853057] ? __might_fault+0x188/0x1d0 [ 135.857087] ? do_raw_spin_trylock+0x190/0x190 [ 135.861635] mm_release+0x46d/0x590 [ 135.865231] ? do_raw_spin_trylock+0x190/0x190 [ 135.869777] ? mm_access+0x140/0x140 [ 135.873455] ? _raw_spin_unlock_irq+0x27/0x70 [ 135.877918] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 135.882899] ? trace_hardirqs_on+0xd/0x10 [ 135.887017] ? _raw_spin_unlock_irq+0x27/0x70 [ 135.891484] ? acct_collect+0x637/0x800 [ 135.895424] do_exit+0x481/0x1b00 [ 135.898844] ? mm_update_next_owner+0x930/0x930 [ 135.903485] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 135.909342] ? find_held_lock+0x39/0x1d0 [ 135.913375] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 135.918706] ? check_noncircular+0x20/0x20 [ 135.922910] ? fault_in_user_writeable+0x90/0x90 [ 135.927635] ? futex_wake+0x680/0x680 [ 135.931408] ? find_held_lock+0x39/0x1d0 [ 135.935438] ? lock_downgrade+0x990/0x990 [ 135.939553] ? recalc_sigpending_tsk+0x117/0x150 [ 135.944277] ? recalc_sigpending+0x103/0x160 [ 135.948655] ? recalc_sigpending_tsk+0x150/0x150 [ 135.953379] ? get_signal+0x2b2/0x16d0 [ 135.957242] do_group_exit+0x149/0x400 [ 135.961105] ? __lock_is_held+0xbc/0x140 [ 135.965133] ? SyS_exit+0x30/0x30 [ 135.968552] ? _raw_spin_unlock_irq+0x27/0x70 [ 135.973020] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 135.978016] get_signal+0x73f/0x16d0 [ 135.981704] ? ptrace_notify+0x130/0x130 [ 135.985748] ? __schedule+0x8f0/0x2070 [ 135.989605] ? exit_robust_list+0x240/0x240 [ 135.993895] ? lock_downgrade+0x990/0x990 [ 135.998013] ? SyS_brk+0x6f0/0x6f0 [ 136.001527] do_signal+0x94/0x1ee0 [ 136.005040] ? arch_get_unmapped_area+0x750/0x750 [ 136.009853] ? lock_acquire+0x1d5/0x580 [ 136.013802] ? find_held_lock+0x39/0x1d0 [ 136.017837] ? setup_sigcontext+0x7d0/0x7d0 [ 136.022127] ? lock_downgrade+0x990/0x990 [ 136.026245] ? down_write+0x120/0x120 [ 136.030015] ? SyS_unshare+0x4a0/0xfa0 [ 136.033874] ? lock_release+0xd70/0xd70 [ 136.037817] ? walk_process_tree+0x400/0x400 [ 136.042193] ? exit_to_usermode_loop+0x8c/0x310 [ 136.046830] exit_to_usermode_loop+0x214/0x310 [ 136.051379] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 136.056881] ? kasan_check_write+0x14/0x20 [ 136.061082] syscall_return_slowpath+0x42f/0x510 [ 136.065805] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 136.070789] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 136.075695] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 136.080678] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 136.085407] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 136.090129] RIP: 0033:0x4520a9 [ 136.093286] RSP: 002b:00007f728d666cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 136.100956] RAX: fffffffffffffe00 RBX: 0000000000718028 RCX: 00000000004520a9 [ 136.108194] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718028 [ 136.115429] RBP: 0000000000718000 R08: 0000000000000000 R09: 0000000000000000 [ 136.122669] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 136.129912] R13: 00007ffcf7f8238f R14: 00007f728d6679c0 R15: 0000000000000000 [ 136.137151] [ 136.138743] Allocated by task 5665: [ 136.142345] save_stack_trace+0x16/0x20 [ 136.146289] save_stack+0x43/0xd0 [ 136.149707] kasan_kmalloc+0xad/0xe0 [ 136.153383] kmem_cache_alloc_trace+0x136/0x750 [ 136.158023] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 136.163100] futex_requeue+0x1887/0x2370 [ 136.167126] do_futex+0x7f5/0x20d0 [ 136.170635] SyS_futex+0x260/0x390 [ 136.174142] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 136.178857] [ 136.180447] Freed by task 5652: [ 136.183692] save_stack_trace+0x16/0x20 [ 136.187632] save_stack+0x43/0xd0 [ 136.191056] kasan_slab_free+0x71/0xc0 [ 136.194908] kfree+0xca/0x250 [ 136.197978] put_pi_state+0x3f4/0x560 [ 136.201741] unqueue_me_pi+0x4a/0xc0 [ 136.205417] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 136.211178] do_futex+0x825/0x20d0 [ 136.214684] SyS_futex+0x260/0x390 [ 136.218190] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 136.222906] [ 136.224501] The buggy address belongs to the object at ffff8801c6922d40 [ 136.224501] which belongs to the cache kmalloc-256 of size 256 [ 136.237119] The buggy address is located 40 bytes inside of [ 136.237119] 256-byte region [ffff8801c6922d40, ffff8801c6922e40) [ 136.248866] The buggy address belongs to the page: [ 136.253761] page:ffffea00071a4880 count:1 mapcount:0 mapping:ffff8801c69220c0 index:0x0 [ 136.261867] flags: 0x200000000000100(slab) [ 136.266074] raw: 0200000000000100 ffff8801c69220c0 0000000000000000 000000010000000c [ 136.273919] raw: ffffea00071b9a60 ffffea00071ad060 ffff8801dac007c0 0000000000000000 [ 136.281763] page dumped because: kasan: bad access detected [ 136.287436] [ 136.289037] Memory state around the buggy address: [ 136.293931] ffff8801c6922c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 136.301252] ffff8801c6922c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 136.308575] >ffff8801c6922d00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 136.315898] ^ [ 136.322616] ffff8801c6922d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 136.329954] ffff8801c6922e00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 136.337276] ================================================================== [ 136.344602] Disabling lock debugging due to kernel taint [ 136.350026] Kernel panic - not syncing: panic_on_warn set ... [ 136.350026] [ 136.357356] CPU: 0 PID: 5638 Comm: syz-executor7 Tainted: G B 4.14.0-rc2-next-20170927+ #30 [ 136.366934] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 136.376251] Call Trace: [ 136.378805] dump_stack+0x194/0x257 [ 136.382396] ? arch_local_irq_restore+0x53/0x53 [ 136.387034] ? vprintk_default+0x28/0x30 [ 136.391065] ? __lock_acquire+0x3f80/0x4620 [ 136.395351] panic+0x1e4/0x417 [ 136.398508] ? __warn+0x1d9/0x1d9 [ 136.401928] ? __lock_acquire+0x407b/0x4620 [ 136.406215] kasan_end_report+0x50/0x50 [ 136.410154] kasan_report+0x144/0x340 [ 136.413920] __asan_report_load8_noabort+0x14/0x20 [ 136.418815] __lock_acquire+0x407b/0x4620 [ 136.422938] ? unwind_dump+0x4c0/0x4c0 [ 136.426789] ? __unwind_start+0x169/0x330 [ 136.430904] ? __kernel_text_address+0xd/0x40 [ 136.435362] ? unwind_get_return_address+0x61/0xa0 [ 136.440259] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 136.445411] ? unwind_get_return_address+0x61/0xa0 [ 136.450307] ? __save_stack_trace+0x61/0xd0 [ 136.454597] ? get_signal+0x73f/0x16d0 [ 136.458449] ? save_stack_trace+0x16/0x20 [ 136.462563] ? __lock_acquire+0x20fd/0x4620 [ 136.466852] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 136.472025] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 136.477181] ? save_stack_trace+0x16/0x20 [ 136.481292] ? __lock_acquire+0x20fd/0x4620 [ 136.485579] ? osq_unlock+0x350/0x350 [ 136.489344] ? save_stack_trace+0x16/0x20 [ 136.493457] ? lock_release+0xd70/0xd70 [ 136.497395] ? check_noncircular+0x20/0x20 [ 136.501596] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 136.506752] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 136.511909] ? find_held_lock+0x39/0x1d0 [ 136.515936] ? lock_downgrade+0x990/0x990 [ 136.520047] ? check_noncircular+0x20/0x20 [ 136.524246] lock_acquire+0x1d5/0x580 [ 136.528025] ? exit_pi_state_list+0x369/0x7a0 [ 136.532487] ? lock_release+0xd70/0xd70 [ 136.536427] ? do_raw_spin_trylock+0x190/0x190 [ 136.540971] ? find_held_lock+0x39/0x1d0 [ 136.545000] _raw_spin_lock_irq+0x5e/0x80 [ 136.549118] ? exit_pi_state_list+0x369/0x7a0 [ 136.553576] exit_pi_state_list+0x369/0x7a0 [ 136.557866] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 136.563891] ? lock_release+0xd70/0xd70 [ 136.567837] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 136.573686] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 136.578754] ? __might_sleep+0x95/0x190 [ 136.582694] ? __might_fault+0x188/0x1d0 [ 136.586720] ? do_raw_spin_trylock+0x190/0x190 [ 136.591266] mm_release+0x46d/0x590 [ 136.594859] ? do_raw_spin_trylock+0x190/0x190 [ 136.599404] ? mm_access+0x140/0x140 [ 136.603081] ? _raw_spin_unlock_irq+0x27/0x70