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-kasan-gce-386-2,10.128.0.62' (ECDSA) to the list of known hosts. 2017/10/03 22:34:01 parsed 1 programs 2017/10/03 22:34:01 executed programs: 0 syzkaller login: [ 40.636631] ================================================================== [ 40.644008] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 40.650636] Read of size 8 at addr ffff8801ce6080a8 by task syz-executor6/3264 [ 40.657954] [ 40.659548] CPU: 1 PID: 3264 Comm: syz-executor6 Not tainted 4.14.0-rc3+ #23 [ 40.666693] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 40.676008] Call Trace: [ 40.678559] dump_stack+0x194/0x257 [ 40.682159] ? arch_local_irq_restore+0x53/0x53 [ 40.686789] ? show_regs_print_info+0x65/0x65 [ 40.691248] ? __kernel_text_address+0xd/0x40 [ 40.695708] ? __lock_acquire+0x407b/0x4620 [ 40.699992] print_address_description+0x73/0x250 [ 40.704797] ? __lock_acquire+0x407b/0x4620 [ 40.709080] kasan_report+0x25b/0x340 [ 40.712842] __asan_report_load8_noabort+0x14/0x20 [ 40.717733] __lock_acquire+0x407b/0x4620 [ 40.721843] ? unwind_dump+0x4c0/0x4c0 [ 40.725692] ? __kernel_text_address+0xd/0x40 [ 40.730149] ? unwind_get_return_address+0x61/0xa0 [ 40.735045] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 40.740198] ? __save_stack_trace+0x61/0xd0 [ 40.744483] ? get_signal+0x73f/0x16d0 [ 40.748336] ? save_stack_trace+0x16/0x20 [ 40.752445] ? __lock_acquire+0x20fd/0x4620 [ 40.756734] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 40.761889] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 40.767040] ? save_stack_trace+0x16/0x20 [ 40.771151] ? __lock_acquire+0x20fd/0x4620 [ 40.775434] ? osq_unlock+0x350/0x350 [ 40.779195] ? save_stack_trace+0x16/0x20 [ 40.783312] ? check_noncircular+0x20/0x20 [ 40.787509] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 40.792663] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 40.797821] ? __unwind_start+0x169/0x330 [ 40.801935] ? find_held_lock+0x39/0x1d0 [ 40.805964] ? lock_downgrade+0x990/0x990 [ 40.810075] ? check_noncircular+0x20/0x20 [ 40.814273] lock_acquire+0x1d5/0x580 [ 40.818037] ? exit_pi_state_list+0x369/0x7a0 [ 40.822496] ? lock_release+0xd70/0xd70 [ 40.826431] ? do_raw_spin_trylock+0x190/0x190 [ 40.830979] ? find_held_lock+0x39/0x1d0 [ 40.835009] _raw_spin_lock_irq+0x5e/0x80 [ 40.839118] ? exit_pi_state_list+0x369/0x7a0 [ 40.843578] exit_pi_state_list+0x369/0x7a0 [ 40.847868] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 40.853891] ? lock_release+0xd70/0xd70 [ 40.857827] ? check_same_owner+0x320/0x320 [ 40.862111] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 40.867189] ? __might_sleep+0x95/0x190 [ 40.871131] ? __might_fault+0x188/0x1d0 [ 40.875155] ? do_raw_spin_trylock+0x190/0x190 [ 40.879703] mm_release+0x46d/0x590 [ 40.883292] ? do_raw_spin_trylock+0x190/0x190 [ 40.887843] ? mm_access+0x140/0x140 [ 40.891523] ? _raw_spin_unlock_irq+0x27/0x70 [ 40.895989] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 40.900971] ? trace_hardirqs_on+0xd/0x10 [ 40.905080] ? _raw_spin_unlock_irq+0x27/0x70 [ 40.909536] ? acct_collect+0x637/0x800 [ 40.913474] do_exit+0x481/0x1af0 [ 40.916891] ? mm_update_next_owner+0x930/0x930 [ 40.921523] ? lock_downgrade+0x990/0x990 [ 40.925632] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 40.930957] ? futex_wait+0x3ad/0x990 [ 40.934720] ? do_raw_spin_trylock+0x190/0x190 [ 40.939266] ? fault_in_user_writeable+0x90/0x90 [ 40.943983] ? futex_wake+0x680/0x680 [ 40.947747] ? fault_in_user_writeable+0x90/0x90 [ 40.952464] ? check_noncircular+0x20/0x20 [ 40.956663] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 40.961727] ? futex_wait+0x69e/0x990 [ 40.965491] ? futex_wait_setup+0x3d0/0x3d0 [ 40.969774] ? find_held_lock+0x39/0x1d0 [ 40.973802] ? lock_downgrade+0x990/0x990 [ 40.977914] ? recalc_sigpending_tsk+0x117/0x150 [ 40.982633] ? recalc_sigpending+0x103/0x160 [ 40.987004] ? recalc_sigpending_tsk+0x150/0x150 [ 40.991720] ? get_signal+0x2b2/0x16d0 [ 40.995571] do_group_exit+0x149/0x400 [ 40.999423] ? __lock_is_held+0xbc/0x140 [ 41.003447] ? SyS_exit+0x30/0x30 [ 41.006865] ? _raw_spin_unlock_irq+0x27/0x70 [ 41.011326] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 41.016308] get_signal+0x73f/0x16d0 [ 41.019988] ? ptrace_notify+0x130/0x130 [ 41.024015] ? depot_save_stack+0x12c/0x490 [ 41.028304] ? do_handle_open+0x598/0x8a0 [ 41.032416] ? save_stack+0xa3/0xd0 [ 41.036484] ? save_stack_trace+0x16/0x20 [ 41.040598] ? save_stack+0x43/0xd0 [ 41.044187] ? kasan_slab_free+0x71/0xc0 [ 41.048211] ? kfree+0xca/0x250 [ 41.051453] ? do_handle_open+0x598/0x8a0 [ 41.055565] ? compat_SyS_open_by_handle_at+0x24/0x30 [ 41.060717] ? do_fast_syscall_32+0x3f2/0xf05 [ 41.065174] ? entry_SYSENTER_compat+0x51/0x60 [ 41.069724] do_signal+0x94/0x1ee0 [ 41.073229] ? __might_fault+0xe0/0x1d0 [ 41.077170] ? setup_sigcontext+0x7d0/0x7d0 [ 41.081458] ? fget_raw+0x20/0x20 [ 41.084875] ? __check_object_size+0x25d/0x4f0 [ 41.089425] ? trace_hardirqs_off+0xd/0x10 [ 41.093623] ? quarantine_put+0xeb/0x190 [ 41.097647] ? kfree+0xe4/0x250 [ 41.100889] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 41.105872] ? trace_hardirqs_on+0xd/0x10 [ 41.109988] ? exit_to_usermode_loop+0x8c/0x310 [ 41.114620] exit_to_usermode_loop+0x214/0x310 [ 41.119170] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 41.124669] ? lock_acquire+0x1d5/0x580 [ 41.128608] ? do_fast_syscall_32+0x158/0xf05 [ 41.133070] do_fast_syscall_32+0x83e/0xf05 [ 41.137361] ? compat_start_thread+0x80/0x80 [ 41.141734] ? do_int80_syscall_32+0x940/0x940 [ 41.146288] ? lockdep_sys_exit+0x47/0xf0 [ 41.150400] ? syscall_return_slowpath+0x2b3/0x510 [ 41.155295] ? finish_task_switch+0x1aa/0x740 [ 41.159753] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 41.164732] ? sysret32_from_system_call+0x5/0x3b [ 41.169541] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 41.174350] entry_SYSENTER_compat+0x51/0x60 [ 41.178721] RIP: 0023:0xf7fcac79 [ 41.182048] RSP: 002b:00000000f7fc612c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0 [ 41.189719] RAX: fffffffffffffe00 RBX: 0000000008128018 RCX: 0000000000000000 [ 41.196953] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 41.204187] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 41.211424] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 41.218663] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 41.225903] [ 41.227495] Allocated by task 3288: [ 41.231093] save_stack_trace+0x16/0x20 [ 41.235032] save_stack+0x43/0xd0 [ 41.238452] kasan_kmalloc+0xad/0xe0 [ 41.242130] kmem_cache_alloc_trace+0x136/0x750 [ 41.246761] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 41.251825] futex_requeue+0x1887/0x2370 [ 41.255847] do_futex+0x7f5/0x20d0 [ 41.259349] compat_SyS_futex+0x27f/0x380 [ 41.263462] do_fast_syscall_32+0x3f2/0xf05 [ 41.267747] entry_SYSENTER_compat+0x51/0x60 [ 41.272115] [ 41.273705] Freed by task 3276: [ 41.276951] save_stack_trace+0x16/0x20 [ 41.280891] save_stack+0x43/0xd0 [ 41.284306] kasan_slab_free+0x71/0xc0 [ 41.288159] kfree+0xca/0x250 [ 41.291231] put_pi_state+0x3f4/0x560 [ 41.294996] unqueue_me_pi+0x4a/0xc0 [ 41.298672] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 41.304434] do_futex+0x825/0x20d0 [ 41.307939] compat_SyS_futex+0x27f/0x380 [ 41.312067] do_fast_syscall_32+0x3f2/0xf05 [ 41.316353] entry_SYSENTER_compat+0x51/0x60 [ 41.320720] [ 41.322314] The buggy address belongs to the object at ffff8801ce608080 [ 41.322314] which belongs to the cache kmalloc-256 of size 256 [ 41.334941] The buggy address is located 40 bytes inside of [ 41.334941] 256-byte region [ffff8801ce608080, ffff8801ce608180) [ 41.346689] The buggy address belongs to the page: [ 41.351583] page:ffffea0007398200 count:1 mapcount:0 mapping:ffff8801ce608080 index:0x0 [ 41.359688] flags: 0x200000000000100(slab) [ 41.363886] raw: 0200000000000100 ffff8801ce608080 0000000000000000 000000010000000c [ 41.371731] raw: ffffea00073929a0 ffffea000739d8e0 ffff8801dac007c0 0000000000000000 [ 41.379571] page dumped because: kasan: bad access detected [ 41.385240] [ 41.386835] Memory state around the buggy address: [ 41.391725] ffff8801ce607f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 41.399047] ffff8801ce608000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 41.406368] >ffff8801ce608080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 41.413687] ^ [ 41.418319] ffff8801ce608100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 41.425640] ffff8801ce608180: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 41.432959] ================================================================== [ 41.440279] Disabling lock debugging due to kernel taint [ 41.445689] Kernel panic - not syncing: panic_on_warn set ... [ 41.445689] [ 41.453012] CPU: 1 PID: 3264 Comm: syz-executor6 Tainted: G B 4.14.0-rc3+ #23 [ 41.461374] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.470689] Call Trace: [ 41.473243] dump_stack+0x194/0x257 [ 41.476838] ? arch_local_irq_restore+0x53/0x53 [ 41.481471] ? vprintk_default+0x28/0x30 [ 41.485496] ? __lock_acquire+0x3ff0/0x4620 [ 41.489779] panic+0x1e4/0x417 [ 41.492936] ? __warn+0x1d9/0x1d9 [ 41.496354] ? __lock_acquire+0x407b/0x4620 [ 41.500637] kasan_end_report+0x50/0x50 [ 41.504574] kasan_report+0x144/0x340 [ 41.508338] __asan_report_load8_noabort+0x14/0x20 [ 41.513232] __lock_acquire+0x407b/0x4620 [ 41.517347] ? unwind_dump+0x4c0/0x4c0 [ 41.521200] ? __kernel_text_address+0xd/0x40 [ 41.525656] ? unwind_get_return_address+0x61/0xa0 [ 41.530549] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 41.535701] ? __save_stack_trace+0x61/0xd0 [ 41.539989] ? get_signal+0x73f/0x16d0 [ 41.543838] ? save_stack_trace+0x16/0x20 [ 41.547951] ? __lock_acquire+0x20fd/0x4620 [ 41.552237] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 41.557395] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 41.562548] ? save_stack_trace+0x16/0x20 [ 41.566658] ? __lock_acquire+0x20fd/0x4620 [ 41.570941] ? osq_unlock+0x350/0x350 [ 41.574702] ? save_stack_trace+0x16/0x20 [ 41.578815] ? check_noncircular+0x20/0x20 [ 41.583015] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 41.588169] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 41.593322] ? __unwind_start+0x169/0x330 [ 41.597435] ? find_held_lock+0x39/0x1d0 [ 41.601464] ? lock_downgrade+0x990/0x990 [ 41.605573] ? check_noncircular+0x20/0x20 [ 41.609772] lock_acquire+0x1d5/0x580 [ 41.613535] ? exit_pi_state_list+0x369/0x7a0 [ 41.617993] ? lock_release+0xd70/0xd70 [ 41.621929] ? do_raw_spin_trylock+0x190/0x190 [ 41.626472] ? find_held_lock+0x39/0x1d0 [ 41.630501] _raw_spin_lock_irq+0x5e/0x80 [ 41.634613] ? exit_pi_state_list+0x369/0x7a0