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-386-3,10.128.0.38' (ECDSA) to the list of known hosts. 2017/10/04 02:14:13 parsed 1 programs 2017/10/04 02:14:13 executed programs: 0 2017/10/04 02:14:18 executed programs: 342 2017/10/04 02:14:23 executed programs: 667 syzkaller login: [ 73.506486] ================================================================== [ 73.513937] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 73.520580] Read of size 8 at addr ffff8801d81ac528 by task syz-executor7/8567 [ 73.527917] [ 73.529530] CPU: 0 PID: 8567 Comm: syz-executor7 Not tainted 4.14.0-rc3+ #23 [ 73.536796] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.546124] Call Trace: [ 73.548695] dump_stack+0x194/0x257 [ 73.552315] ? arch_local_irq_restore+0x53/0x53 [ 73.556977] ? show_regs_print_info+0x65/0x65 [ 73.561462] ? __kernel_text_address+0xd/0x40 [ 73.565948] ? __lock_acquire+0x407b/0x4620 [ 73.570249] print_address_description+0x73/0x250 [ 73.575083] ? __lock_acquire+0x407b/0x4620 [ 73.579398] kasan_report+0x25b/0x340 [ 73.583182] __asan_report_load8_noabort+0x14/0x20 [ 73.588106] __lock_acquire+0x407b/0x4620 [ 73.592243] ? unwind_dump+0x4c0/0x4c0 [ 73.596128] ? __kernel_text_address+0xd/0x40 [ 73.600623] ? unwind_get_return_address+0x61/0xa0 [ 73.605554] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 73.610725] ? __save_stack_trace+0x61/0xd0 [ 73.615030] ? get_signal+0x73f/0x16d0 [ 73.618898] ? save_stack_trace+0x16/0x20 [ 73.623030] ? __lock_acquire+0x20fd/0x4620 [ 73.627337] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 73.632504] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 73.637663] ? save_stack_trace+0x16/0x20 [ 73.641779] ? __lock_acquire+0x20fd/0x4620 [ 73.646067] ? osq_unlock+0x350/0x350 [ 73.649835] ? save_stack_trace+0x16/0x20 [ 73.653953] ? check_noncircular+0x20/0x20 [ 73.658156] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 73.663312] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 73.668484] ? find_held_lock+0x39/0x1d0 [ 73.672530] ? lock_downgrade+0x990/0x990 [ 73.676646] ? check_noncircular+0x20/0x20 [ 73.680849] lock_acquire+0x1d5/0x580 [ 73.684618] ? exit_pi_state_list+0x369/0x7a0 [ 73.689084] ? lock_release+0xd70/0xd70 [ 73.693031] ? do_raw_spin_trylock+0x190/0x190 [ 73.697581] ? find_held_lock+0x39/0x1d0 [ 73.701617] _raw_spin_lock_irq+0x5e/0x80 [ 73.705734] ? exit_pi_state_list+0x369/0x7a0 [ 73.710195] exit_pi_state_list+0x369/0x7a0 [ 73.714487] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 73.720511] ? lock_release+0xd70/0xd70 [ 73.724453] ? check_same_owner+0x320/0x320 [ 73.728742] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 73.733816] ? __might_sleep+0x95/0x190 [ 73.737761] ? __might_fault+0x188/0x1d0 [ 73.741792] ? do_raw_spin_trylock+0x190/0x190 [ 73.746343] mm_release+0x46d/0x590 [ 73.749935] ? do_raw_spin_trylock+0x190/0x190 [ 73.754484] ? mm_access+0x140/0x140 [ 73.758167] ? _raw_spin_unlock_irq+0x27/0x70 [ 73.762631] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 73.767622] ? trace_hardirqs_on+0xd/0x10 [ 73.771738] ? _raw_spin_unlock_irq+0x27/0x70 [ 73.776204] ? acct_collect+0x637/0x800 [ 73.780156] do_exit+0x481/0x1af0 [ 73.783580] ? __might_sleep+0x95/0x190 [ 73.787524] ? mm_update_next_owner+0x930/0x930 [ 73.792173] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 73.797514] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 73.802671] ? get_futex_value_locked+0xc3/0xf0 [ 73.807308] ? futex_wait_setup+0x22e/0x3d0 [ 73.811599] ? futex_wake+0x680/0x680 [ 73.815376] ? check_noncircular+0x20/0x20 [ 73.819578] ? __lock_acquire+0x732/0x4620 [ 73.823781] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 73.828850] ? futex_wait+0x69e/0x990 [ 73.832621] ? futex_wait_setup+0x3d0/0x3d0 [ 73.836909] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 73.842066] ? find_held_lock+0x39/0x1d0 [ 73.846103] ? lock_downgrade+0x990/0x990 [ 73.850222] ? recalc_sigpending_tsk+0x117/0x150 [ 73.854943] ? recalc_sigpending+0x103/0x160 [ 73.859322] ? recalc_sigpending_tsk+0x150/0x150 [ 73.864042] ? get_signal+0x2b2/0x16d0 [ 73.867901] do_group_exit+0x149/0x400 [ 73.871758] ? __lock_is_held+0xbc/0x140 [ 73.875787] ? SyS_exit+0x30/0x30 [ 73.879211] ? _raw_spin_unlock_irq+0x27/0x70 [ 73.883673] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 73.888658] get_signal+0x73f/0x16d0 [ 73.892342] ? ptrace_notify+0x130/0x130 [ 73.896369] ? lock_release+0xd70/0xd70 [ 73.900311] ? __lock_is_held+0xbc/0x140 [ 73.904345] ? __fget+0x362/0x580 [ 73.907769] do_signal+0x94/0x1ee0 [ 73.911274] ? iterate_fd+0x3f0/0x3f0 [ 73.915045] ? setup_sigcontext+0x7d0/0x7d0 [ 73.919337] ? __fget_light+0x29d/0x390 [ 73.923280] ? handle_mm_fault+0x410/0x8d0 [ 73.927481] ? down_read_trylock+0xdb/0x170 [ 73.931771] ? __do_page_fault+0x31e/0xd60 [ 73.935978] ? exit_to_usermode_loop+0x8c/0x310 [ 73.940618] exit_to_usermode_loop+0x214/0x310 [ 73.945166] ? fput+0xd2/0x140 [ 73.948327] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 73.953831] ? do_fast_syscall_32+0x158/0xf05 [ 73.958294] do_fast_syscall_32+0x83e/0xf05 [ 73.962585] ? do_int80_syscall_32+0x940/0x940 [ 73.967137] ? lockdep_sys_exit+0x47/0xf0 [ 73.971252] ? syscall_return_slowpath+0x2b3/0x510 [ 73.976149] ? finish_task_switch+0x1aa/0x740 [ 73.980615] ? sysret32_from_system_call+0x5/0x3b [ 73.985424] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 73.990234] entry_SYSENTER_compat+0x51/0x60 [ 73.994610] RIP: 0023:0xf7f84c79 [ 73.997940] RSP: 002b:00000000f7f3e12c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0 [ 74.005615] RAX: 0000000000000000 RBX: 00000000081280f8 RCX: 0000000000000000 [ 74.012853] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 74.020090] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 74.027329] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 74.034568] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 74.041818] [ 74.043415] Allocated by task 8586: [ 74.047015] save_stack_trace+0x16/0x20 [ 74.050962] save_stack+0x43/0xd0 [ 74.054384] kasan_kmalloc+0xad/0xe0 [ 74.058068] kmem_cache_alloc_trace+0x136/0x750 [ 74.062707] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 74.067774] futex_requeue+0x1887/0x2370 [ 74.071802] do_futex+0x7f5/0x20d0 [ 74.075309] compat_SyS_futex+0x27f/0x380 [ 74.079424] do_fast_syscall_32+0x3f2/0xf05 [ 74.083713] entry_SYSENTER_compat+0x51/0x60 [ 74.088085] [ 74.089679] Freed by task 8556: [ 74.092924] save_stack_trace+0x16/0x20 [ 74.096863] save_stack+0x43/0xd0 [ 74.100282] kasan_slab_free+0x71/0xc0 [ 74.104136] kfree+0xca/0x250 [ 74.107210] put_pi_state+0x3f4/0x560 [ 74.110977] unqueue_me_pi+0x4a/0xc0 [ 74.114656] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 74.120420] do_futex+0x825/0x20d0 [ 74.123925] compat_SyS_futex+0x27f/0x380 [ 74.128043] do_fast_syscall_32+0x3f2/0xf05 [ 74.132336] entry_SYSENTER_compat+0x51/0x60 [ 74.136706] [ 74.138304] The buggy address belongs to the object at ffff8801d81ac500 [ 74.138304] which belongs to the cache kmalloc-256 of size 256 [ 74.150926] The buggy address is located 40 bytes inside of [ 74.150926] 256-byte region [ffff8801d81ac500, ffff8801d81ac600) [ 74.162676] The buggy address belongs to the page: [ 74.167575] page:ffffea0007606b00 count:1 mapcount:0 mapping:ffff8801d81ac000 index:0xffff8801d81acdc0 [ 74.176988] flags: 0x200000000000100(slab) [ 74.181194] raw: 0200000000000100 ffff8801d81ac000 ffff8801d81acdc0 0000000100000009 [ 74.189041] raw: ffffea000760dbe0 ffffea000762c160 ffff8801dac007c0 0000000000000000 [ 74.196886] page dumped because: kasan: bad access detected [ 74.202561] [ 74.204154] Memory state around the buggy address: [ 74.209055] ffff8801d81ac400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 74.216379] ffff8801d81ac480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 74.223707] >ffff8801d81ac500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 74.231031] ^ [ 74.235667] ffff8801d81ac580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 74.242990] ffff8801d81ac600: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 [ 74.250313] ================================================================== [ 74.257635] Disabling lock debugging due to kernel taint [ 74.263055] Kernel panic - not syncing: panic_on_warn set ... [ 74.263055] [ 74.270385] CPU: 0 PID: 8567 Comm: syz-executor7 Tainted: G B 4.14.0-rc3+ #23 [ 74.278750] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 74.288071] Call Trace: [ 74.290637] dump_stack+0x194/0x257 [ 74.294240] ? arch_local_irq_restore+0x53/0x53 [ 74.298878] ? vprintk_default+0x28/0x30 [ 74.302908] ? __lock_acquire+0x3ff0/0x4620 [ 74.307198] panic+0x1e4/0x417 [ 74.310356] ? __warn+0x1d9/0x1d9 [ 74.313780] ? __lock_acquire+0x407b/0x4620 [ 74.318069] kasan_end_report+0x50/0x50 [ 74.322012] kasan_report+0x144/0x340 [ 74.325782] __asan_report_load8_noabort+0x14/0x20 [ 74.330679] __lock_acquire+0x407b/0x4620 [ 74.334798] ? unwind_dump+0x4c0/0x4c0 [ 74.338653] ? __kernel_text_address+0xd/0x40 [ 74.343115] ? unwind_get_return_address+0x61/0xa0 [ 74.348015] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 74.353175] ? __save_stack_trace+0x61/0xd0 [ 74.357466] ? get_signal+0x73f/0x16d0 [ 74.361321] ? save_stack_trace+0x16/0x20 [ 74.365434] ? __lock_acquire+0x20fd/0x4620 [ 74.369724] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 74.374882] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 74.380041] ? save_stack_trace+0x16/0x20 [ 74.384158] ? __lock_acquire+0x20fd/0x4620 [ 74.388445] ? osq_unlock+0x350/0x350 [ 74.392211] ? save_stack_trace+0x16/0x20 [ 74.396329] ? check_noncircular+0x20/0x20 [ 74.400530] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 74.405687] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 74.410844] ? find_held_lock+0x39/0x1d0 [ 74.414877] ? lock_downgrade+0x990/0x990 [ 74.418989] ? check_noncircular+0x20/0x20 [ 74.423194] lock_acquire+0x1d5/0x580 [ 74.426964] ? exit_pi_state_list+0x369/0x7a0 [ 74.431429] ? lock_release+0xd70/0xd70 [ 74.435371] ? do_raw_spin_trylock+0x190/0x190 [ 74.439920] ? find_held_lock+0x39/0x1d0 [ 74.443953] _raw_spin_lock_irq+0x5e/0x80 [ 74.448069] ? exit_pi_state_list+0x369/0x7a0 [ 74.452531] exit_pi_state_list+0x369/0x7a0 [ 74.456824] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 74.462850] ? lock_release+0xd70/0xd70 [ 74.466791] ? check_same_owner+0x320/0x320 [ 74.471080] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 74.476153] ? __might_sleep+0x95/0x190 [ 74.480097] ? __might_fault+0x188/0x1d0 [ 74.484126] ? do_raw_spin_trylock+0x190/0x190 [ 74.488678] mm_release+0x46d/0x590 [ 74.492271] ? do_raw_spin_trylock+0x190/0x190 [ 74.496817] ? mm_access+0x140/0x140 [ 74.500500] ? _raw_spin_unlock_irq+0x27/0x70 [ 74.504964] ? trace_hardirqs_on_caller+0x421/0x5c0