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-386-2,10.128.0.57' (ECDSA) to the list of known hosts. 2017/10/04 07:05:07 parsed 1 programs 2017/10/04 07:05:07 executed programs: 0 2017/10/04 07:05:12 executed programs: 390 syzkaller login: [ 47.940911] ================================================================== [ 47.948359] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 47.955006] Read of size 8 at addr ffff8801c7a7e2e8 by task syz-executor2/5616 [ 47.962338] [ 47.963943] CPU: 1 PID: 5616 Comm: syz-executor2 Not tainted 4.14.0-rc3+ #24 [ 47.971105] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.980431] Call Trace: [ 47.982997] dump_stack+0x194/0x257 [ 47.986602] ? arch_local_irq_restore+0x53/0x53 [ 47.991247] ? show_regs_print_info+0x65/0x65 [ 47.995721] ? __kernel_text_address+0xd/0x40 [ 48.000192] ? __lock_acquire+0x407b/0x4620 [ 48.004496] print_address_description+0x73/0x250 [ 48.009314] ? __lock_acquire+0x407b/0x4620 [ 48.013605] kasan_report+0x25b/0x340 [ 48.017385] __asan_report_load8_noabort+0x14/0x20 [ 48.022293] __lock_acquire+0x407b/0x4620 [ 48.026432] ? unwind_dump+0x4c0/0x4c0 [ 48.030308] ? __kernel_text_address+0xd/0x40 [ 48.034796] ? unwind_get_return_address+0x61/0xa0 [ 48.039703] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 48.044862] ? __save_stack_trace+0x61/0xd0 [ 48.049151] ? get_signal+0x73f/0x16d0 [ 48.053005] ? save_stack_trace+0x16/0x20 [ 48.057132] ? __lock_acquire+0x20fd/0x4620 [ 48.061430] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 48.066591] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 48.071755] ? save_stack_trace+0x16/0x20 [ 48.075876] ? __lock_acquire+0x20fd/0x4620 [ 48.080170] ? osq_unlock+0x350/0x350 [ 48.083944] ? save_stack_trace+0x16/0x20 [ 48.088068] ? check_noncircular+0x20/0x20 [ 48.092274] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 48.097431] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 48.102596] ? __unwind_start+0x169/0x330 [ 48.106720] ? find_held_lock+0x39/0x1d0 [ 48.110765] ? lock_downgrade+0x990/0x990 [ 48.114895] ? check_noncircular+0x20/0x20 [ 48.119097] lock_acquire+0x1d5/0x580 [ 48.122866] ? exit_pi_state_list+0x369/0x7a0 [ 48.127338] ? lock_release+0xd70/0xd70 [ 48.131300] ? do_raw_spin_trylock+0x190/0x190 [ 48.135859] ? find_held_lock+0x39/0x1d0 [ 48.139900] _raw_spin_lock_irq+0x5e/0x80 [ 48.144018] ? exit_pi_state_list+0x369/0x7a0 [ 48.148489] exit_pi_state_list+0x369/0x7a0 [ 48.152797] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 48.158831] ? lock_release+0xd70/0xd70 [ 48.162780] ? check_same_owner+0x320/0x320 [ 48.167068] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 48.172146] ? __might_sleep+0x95/0x190 [ 48.176097] ? __might_fault+0x188/0x1d0 [ 48.180133] ? do_raw_spin_trylock+0x190/0x190 [ 48.184685] mm_release+0x46d/0x590 [ 48.188277] ? do_raw_spin_trylock+0x190/0x190 [ 48.192825] ? mm_access+0x140/0x140 [ 48.196508] ? _raw_spin_unlock_irq+0x27/0x70 [ 48.200981] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 48.205972] ? trace_hardirqs_on+0xd/0x10 [ 48.210098] ? _raw_spin_unlock_irq+0x27/0x70 [ 48.214562] ? acct_collect+0x637/0x800 [ 48.218502] do_exit+0x481/0x1af0 [ 48.221932] ? mm_update_next_owner+0x930/0x930 [ 48.226580] ? lock_downgrade+0x990/0x990 [ 48.230708] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 48.236051] ? futex_wait+0x3ad/0x990 [ 48.239824] ? do_raw_spin_trylock+0x190/0x190 [ 48.244373] ? fault_in_user_writeable+0x90/0x90 [ 48.249098] ? futex_wake+0x680/0x680 [ 48.252871] ? check_noncircular+0x20/0x20 [ 48.257074] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 48.262142] ? futex_wait+0x69e/0x990 [ 48.265911] ? futex_wait_setup+0x3d0/0x3d0 [ 48.270198] ? find_held_lock+0x39/0x1d0 [ 48.274231] ? lock_downgrade+0x990/0x990 [ 48.278352] ? recalc_sigpending_tsk+0x117/0x150 [ 48.283083] ? recalc_sigpending+0x103/0x160 [ 48.287461] ? recalc_sigpending_tsk+0x150/0x150 [ 48.292182] ? get_signal+0x2b2/0x16d0 [ 48.296045] do_group_exit+0x149/0x400 [ 48.299908] ? __lock_is_held+0xbc/0x140 [ 48.303935] ? SyS_exit+0x30/0x30 [ 48.307356] ? _raw_spin_unlock_irq+0x27/0x70 [ 48.311818] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 48.316807] get_signal+0x73f/0x16d0 [ 48.320500] ? ptrace_notify+0x130/0x130 [ 48.324559] do_signal+0x94/0x1ee0 [ 48.328083] ? setup_sigcontext+0x7d0/0x7d0 [ 48.332385] ? find_held_lock+0x39/0x1d0 [ 48.336420] ? __compat_get_timespec+0xd9/0x120 [ 48.341065] ? exit_to_usermode_loop+0x8c/0x310 [ 48.345711] exit_to_usermode_loop+0x214/0x310 [ 48.350270] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 48.355784] ? lock_acquire+0x1d5/0x580 [ 48.359724] ? do_fast_syscall_32+0x158/0xf05 [ 48.364186] do_fast_syscall_32+0x83e/0xf05 [ 48.368476] ? compat_start_thread+0x80/0x80 [ 48.372861] ? do_int80_syscall_32+0x940/0x940 [ 48.377422] ? lockdep_sys_exit+0x47/0xf0 [ 48.381538] ? syscall_return_slowpath+0x2b3/0x510 [ 48.386433] ? finish_task_switch+0x1aa/0x740 [ 48.390902] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 48.395902] ? sysret32_from_system_call+0x5/0x3b [ 48.400726] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 48.405543] entry_SYSENTER_compat+0x51/0x60 [ 48.409915] RIP: 0023:0xf7f32c79 [ 48.413244] RSP: 002b:00000000f7ecb12c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0 [ 48.420921] RAX: fffffffffffffe00 RBX: 0000000008128168 RCX: 0000000000000000 [ 48.428164] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 48.435402] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 48.442637] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 48.449874] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 48.457115] [ 48.458708] Allocated by task 5625: [ 48.462301] save_stack_trace+0x16/0x20 [ 48.466241] save_stack+0x43/0xd0 [ 48.469659] kasan_kmalloc+0xad/0xe0 [ 48.473337] kmem_cache_alloc_trace+0x136/0x750 [ 48.477970] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 48.483039] futex_requeue+0x1887/0x2370 [ 48.487061] do_futex+0x7f5/0x20d0 [ 48.490563] compat_SyS_futex+0x27f/0x380 [ 48.494674] do_fast_syscall_32+0x3f2/0xf05 [ 48.498961] entry_SYSENTER_compat+0x51/0x60 [ 48.503330] [ 48.504921] Freed by task 5589: [ 48.508164] save_stack_trace+0x16/0x20 [ 48.512102] save_stack+0x43/0xd0 [ 48.515517] kasan_slab_free+0x71/0xc0 [ 48.519377] kfree+0xca/0x250 [ 48.522445] put_pi_state+0x3f4/0x560 [ 48.526208] unqueue_me_pi+0x4a/0xc0 [ 48.529884] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 48.535643] do_futex+0x825/0x20d0 [ 48.539145] compat_SyS_futex+0x27f/0x380 [ 48.543255] do_fast_syscall_32+0x3f2/0xf05 [ 48.547541] entry_SYSENTER_compat+0x51/0x60 [ 48.551910] [ 48.553504] The buggy address belongs to the object at ffff8801c7a7e2c0 [ 48.553504] which belongs to the cache kmalloc-256 of size 256 [ 48.566122] The buggy address is located 40 bytes inside of [ 48.566122] 256-byte region [ffff8801c7a7e2c0, ffff8801c7a7e3c0) [ 48.577875] The buggy address belongs to the page: [ 48.582775] page:ffffea00071e9f80 count:1 mapcount:0 mapping:ffff8801c7a7e040 index:0x0 [ 48.590881] flags: 0x200000000000100(slab) [ 48.595081] raw: 0200000000000100 ffff8801c7a7e040 0000000000000000 000000010000000c [ 48.602925] raw: ffffea00071ffc60 ffffea00071d3520 ffff8801dac007c0 0000000000000000 [ 48.610768] page dumped because: kasan: bad access detected [ 48.616439] [ 48.618031] Memory state around the buggy address: [ 48.622921] ffff8801c7a7e180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.630241] ffff8801c7a7e200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.637563] >ffff8801c7a7e280: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 48.644886] ^ [ 48.651605] ffff8801c7a7e300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.658930] ffff8801c7a7e380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 48.666252] ================================================================== [ 48.673574] Disabling lock debugging due to kernel taint [ 48.678987] Kernel panic - not syncing: panic_on_warn set ... [ 48.678987] [ 48.686314] CPU: 1 PID: 5616 Comm: syz-executor2 Tainted: G B 4.14.0-rc3+ #24 [ 48.694677] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.703995] Call Trace: [ 48.706555] dump_stack+0x194/0x257 [ 48.710149] ? arch_local_irq_restore+0x53/0x53 [ 48.714782] ? vprintk_default+0x28/0x30 [ 48.718809] ? __lock_acquire+0x3ff0/0x4620 [ 48.723093] panic+0x1e4/0x417 [ 48.726251] ? __warn+0x1d9/0x1d9 [ 48.729671] ? __lock_acquire+0x407b/0x4620 [ 48.733957] kasan_end_report+0x50/0x50 [ 48.737894] kasan_report+0x144/0x340 [ 48.741660] __asan_report_load8_noabort+0x14/0x20 [ 48.746552] __lock_acquire+0x407b/0x4620 [ 48.750666] ? unwind_dump+0x4c0/0x4c0 [ 48.754517] ? __kernel_text_address+0xd/0x40 [ 48.758975] ? unwind_get_return_address+0x61/0xa0 [ 48.763870] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 48.769024] ? __save_stack_trace+0x61/0xd0 [ 48.773311] ? get_signal+0x73f/0x16d0 [ 48.777164] ? save_stack_trace+0x16/0x20 [ 48.781275] ? __lock_acquire+0x20fd/0x4620 [ 48.785563] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 48.790719] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 48.795871] ? save_stack_trace+0x16/0x20 [ 48.799983] ? __lock_acquire+0x20fd/0x4620 [ 48.804270] ? osq_unlock+0x350/0x350 [ 48.808036] ? save_stack_trace+0x16/0x20 [ 48.812148] ? check_noncircular+0x20/0x20 [ 48.816347] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 48.821503] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 48.826657] ? __unwind_start+0x169/0x330 [ 48.830770] ? find_held_lock+0x39/0x1d0 [ 48.834800] ? lock_downgrade+0x990/0x990 [ 48.838911] ? check_noncircular+0x20/0x20 [ 48.843112] lock_acquire+0x1d5/0x580 [ 48.846876] ? exit_pi_state_list+0x369/0x7a0 [ 48.851337] ? lock_release+0xd70/0xd70 [ 48.855273] ? do_raw_spin_trylock+0x190/0x190 [ 48.859819] ? find_held_lock+0x39/0x1d0 [ 48.863849] _raw_spin_lock_irq+0x5e/0x80 [ 48.867961] ? exit_pi_state_list+0x369/0x7a0 [ 48.872419] exit_pi_state_list+0x369/0x7a0 [ 48.876707] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 48.882728] ? lock_release+0xd70/0xd70 [ 48.886666] ? check_same_owner+0x320/0x320 [ 48.890951] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 48.896023] ? __might_sleep+0x95/0x190 [ 48.899964] ? __might_fault+0x188/0x1d0 [ 48.903988] ? do_raw_spin_trylock+0x190/0x190 [ 48.908534] mm_release+0x46d/0x590 [ 48.912126] ? do_raw_spin_trylock+0x190/0x190 [ 48.916673] ? mm_access+0x140/0x140 [ 48.920349] ? _raw_spin_unlock_irq+0x27/0x70 [ 48.924812] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 48.929791] ? trace_hardirqs_on+0xd/0x10 [ 48.933901] ? _raw_spin_unlock_irq+0x27/0x70 [ 48.938359] ? acct_collect+0x637/0x800