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-386-4,10.128.0.53' (ECDSA) to the list of known hosts. 2017/10/04 14:56:29 parsed 1 programs 2017/10/04 14:56:29 executed programs: 0 2017/10/04 14:56:34 executed programs: 55 2017/10/04 14:56:39 executed programs: 110 syzkaller login: [ 72.642542] ================================================================== [ 72.649927] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 72.656557] Read of size 8 at addr ffff8801cc425228 by task syz-executor0/3663 [ 72.663886] [ 72.665500] CPU: 0 PID: 3663 Comm: syz-executor0 Not tainted 4.14.0-rc3+ #24 [ 72.672648] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 72.681966] Call Trace: [ 72.684523] dump_stack+0x194/0x257 [ 72.688116] ? arch_local_irq_restore+0x53/0x53 [ 72.692749] ? show_regs_print_info+0x65/0x65 [ 72.697211] ? __kernel_text_address+0xd/0x40 [ 72.701671] ? __lock_acquire+0x407b/0x4620 [ 72.705955] print_address_description+0x73/0x250 [ 72.710759] ? __lock_acquire+0x407b/0x4620 [ 72.715042] kasan_report+0x25b/0x340 [ 72.718807] __asan_report_load8_noabort+0x14/0x20 [ 72.723698] __lock_acquire+0x407b/0x4620 [ 72.727809] ? unwind_dump+0x4c0/0x4c0 [ 72.731661] ? __kernel_text_address+0xd/0x40 [ 72.736119] ? unwind_get_return_address+0x61/0xa0 [ 72.741014] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 72.746167] ? __save_stack_trace+0x61/0xd0 [ 72.750458] ? get_signal+0x73f/0x16d0 [ 72.754308] ? save_stack_trace+0x16/0x20 [ 72.758418] ? __lock_acquire+0x20fd/0x4620 [ 72.762708] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 72.767869] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 72.773022] ? save_stack_trace+0x16/0x20 [ 72.777145] ? __lock_acquire+0x20fd/0x4620 [ 72.781428] ? osq_unlock+0x350/0x350 [ 72.785191] ? save_stack_trace+0x16/0x20 [ 72.789304] ? __lock_is_held+0xbc/0x140 [ 72.793330] ? check_noncircular+0x20/0x20 [ 72.797530] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 72.802686] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 72.807846] ? find_held_lock+0x39/0x1d0 [ 72.811872] ? lock_downgrade+0x990/0x990 [ 72.815995] ? check_noncircular+0x20/0x20 [ 72.820194] lock_acquire+0x1d5/0x580 [ 72.823957] ? exit_pi_state_list+0x369/0x7a0 [ 72.828415] ? lock_release+0xd70/0xd70 [ 72.832351] ? do_raw_spin_trylock+0x190/0x190 [ 72.836897] ? find_held_lock+0x39/0x1d0 [ 72.840925] _raw_spin_lock_irq+0x5e/0x80 [ 72.845037] ? exit_pi_state_list+0x369/0x7a0 [ 72.849494] exit_pi_state_list+0x369/0x7a0 [ 72.853781] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 72.859803] ? lock_release+0xd70/0xd70 [ 72.863741] ? check_same_owner+0x320/0x320 [ 72.868026] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 72.873093] ? __might_sleep+0x95/0x190 [ 72.877032] ? __might_fault+0x188/0x1d0 [ 72.881057] ? do_raw_spin_trylock+0x190/0x190 [ 72.885604] mm_release+0x46d/0x590 [ 72.889193] ? do_raw_spin_trylock+0x190/0x190 [ 72.893736] ? mm_access+0x140/0x140 [ 72.897413] ? _raw_spin_unlock_irq+0x27/0x70 [ 72.901870] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 72.906846] ? trace_hardirqs_on+0xd/0x10 [ 72.910956] ? _raw_spin_unlock_irq+0x27/0x70 [ 72.915414] ? acct_collect+0x637/0x800 [ 72.919351] do_exit+0x481/0x1af0 [ 72.922767] ? __might_sleep+0x95/0x190 [ 72.926702] ? mm_update_next_owner+0x930/0x930 [ 72.931338] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 72.936666] ? memset+0x31/0x40 [ 72.939909] ? get_futex_value_locked+0xc3/0xf0 [ 72.944542] ? futex_wait_setup+0x22e/0x3d0 [ 72.948826] ? osq_unlock+0x350/0x350 [ 72.952589] ? futex_wake+0x680/0x680 [ 72.956351] ? fault_in_user_writeable+0x90/0x90 [ 72.961072] ? check_noncircular+0x20/0x20 [ 72.965270] ? futex_wake+0x32d/0x680 [ 72.969033] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 72.974097] ? futex_wait+0x69e/0x990 [ 72.977861] ? do_raw_spin_trylock+0x190/0x190 [ 72.982407] ? futex_wait_setup+0x3d0/0x3d0 [ 72.986693] ? find_held_lock+0x39/0x1d0 [ 72.990717] ? lock_downgrade+0x990/0x990 [ 72.994828] ? recalc_sigpending_tsk+0x117/0x150 [ 72.999544] ? recalc_sigpending+0x103/0x160 [ 73.003915] ? recalc_sigpending_tsk+0x150/0x150 [ 73.008631] ? get_signal+0x2b2/0x16d0 [ 73.012486] do_group_exit+0x149/0x400 [ 73.016338] ? __lock_is_held+0xbc/0x140 [ 73.020364] ? SyS_exit+0x30/0x30 [ 73.023782] ? _raw_spin_unlock_irq+0x27/0x70 [ 73.028240] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 73.033220] get_signal+0x73f/0x16d0 [ 73.036902] ? ptrace_notify+0x130/0x130 [ 73.040926] ? lock_downgrade+0x990/0x990 [ 73.045044] ? cpuset_wait_for_hotplug+0x20/0x20 [ 73.049764] ? do_raw_spin_trylock+0x190/0x190 [ 73.054314] do_signal+0x94/0x1ee0 [ 73.057819] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 73.062802] ? trace_hardirqs_on+0xd/0x10 [ 73.066912] ? cpuset_cpus_allowed+0x270/0x470 [ 73.071458] ? setup_sigcontext+0x7d0/0x7d0 [ 73.075749] ? sched_setaffinity+0x57a/0x9b0 [ 73.080122] ? find_held_lock+0x39/0x1d0 [ 73.084144] ? __compat_get_timespec+0xd9/0x120 [ 73.088777] ? exit_to_usermode_loop+0x8c/0x310 [ 73.093411] exit_to_usermode_loop+0x214/0x310 [ 73.097956] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 73.103456] ? lock_acquire+0x1d5/0x580 [ 73.107392] ? do_fast_syscall_32+0x158/0xf05 [ 73.111851] do_fast_syscall_32+0x83e/0xf05 [ 73.116135] ? compat_start_thread+0x80/0x80 [ 73.120510] ? do_int80_syscall_32+0x940/0x940 [ 73.125058] ? lockdep_sys_exit+0x47/0xf0 [ 73.129169] ? syscall_return_slowpath+0x2b3/0x510 [ 73.134062] ? finish_task_switch+0x1aa/0x740 [ 73.138520] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 73.143502] ? sysret32_from_system_call+0x5/0x3b [ 73.148310] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 73.153116] entry_SYSENTER_compat+0x51/0x60 [ 73.157487] RIP: 0023:0xf7f59c79 [ 73.160813] RSP: 002b:00000000f7f1312c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0 [ 73.168484] RAX: 0000000000000000 RBX: 00000000081280f8 RCX: 0000000000000000 [ 73.175717] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 73.182952] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 73.190188] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 73.197420] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 73.204669] [ 73.206264] Allocated by task 3665: [ 73.209855] save_stack_trace+0x16/0x20 [ 73.213791] save_stack+0x43/0xd0 [ 73.217206] kasan_kmalloc+0xad/0xe0 [ 73.220881] kmem_cache_alloc_trace+0x136/0x750 [ 73.225516] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 73.230582] futex_requeue+0x1887/0x2370 [ 73.234602] do_futex+0x7f5/0x20d0 [ 73.238106] compat_SyS_futex+0x27f/0x380 [ 73.242217] do_fast_syscall_32+0x3f2/0xf05 [ 73.246502] entry_SYSENTER_compat+0x51/0x60 [ 73.250870] [ 73.252460] Freed by task 3662: [ 73.255700] save_stack_trace+0x16/0x20 [ 73.259635] save_stack+0x43/0xd0 [ 73.263049] kasan_slab_free+0x71/0xc0 [ 73.266897] kfree+0xca/0x250 [ 73.269964] put_pi_state+0x3f4/0x560 [ 73.273736] unqueue_me_pi+0x4a/0xc0 [ 73.277411] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 73.283171] do_futex+0x825/0x20d0 [ 73.286672] compat_SyS_futex+0x27f/0x380 [ 73.290781] do_fast_syscall_32+0x3f2/0xf05 [ 73.295064] entry_SYSENTER_compat+0x51/0x60 [ 73.299433] [ 73.301028] The buggy address belongs to the object at ffff8801cc425200 [ 73.301028] which belongs to the cache kmalloc-256 of size 256 [ 73.313645] The buggy address is located 40 bytes inside of [ 73.313645] 256-byte region [ffff8801cc425200, ffff8801cc425300) [ 73.325393] The buggy address belongs to the page: [ 73.330283] page:ffffea0007310940 count:1 mapcount:0 mapping:ffff8801cc4250c0 index:0x0 [ 73.338388] flags: 0x200000000000100(slab) [ 73.342585] raw: 0200000000000100 ffff8801cc4250c0 0000000000000000 000000010000000c [ 73.350429] raw: ffffea0007338120 ffffea0007312b20 ffff8801dac007c0 0000000000000000 [ 73.358275] page dumped because: kasan: bad access detected [ 73.363944] [ 73.365537] Memory state around the buggy address: [ 73.370430] ffff8801cc425100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 73.377751] ffff8801cc425180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 73.385074] >ffff8801cc425200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 73.392396] ^ [ 73.397025] ffff8801cc425280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 73.404348] ffff8801cc425300: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 73.411667] ================================================================== [ 73.418985] Disabling lock debugging due to kernel taint [ 73.424396] Kernel panic - not syncing: panic_on_warn set ... [ 73.424396] [ 73.431721] CPU: 0 PID: 3663 Comm: syz-executor0 Tainted: G B 4.14.0-rc3+ #24 [ 73.440081] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.449397] Call Trace: [ 73.451950] dump_stack+0x194/0x257 [ 73.455542] ? arch_local_irq_restore+0x53/0x53 [ 73.460173] ? vprintk_default+0x28/0x30 [ 73.464196] ? __lock_acquire+0x3ff0/0x4620 [ 73.468484] panic+0x1e4/0x417 [ 73.471641] ? __warn+0x1d9/0x1d9 [ 73.475061] ? __lock_acquire+0x407b/0x4620 [ 73.479348] kasan_end_report+0x50/0x50 [ 73.483282] kasan_report+0x144/0x340 [ 73.487045] __asan_report_load8_noabort+0x14/0x20 [ 73.491938] __lock_acquire+0x407b/0x4620 [ 73.496048] ? unwind_dump+0x4c0/0x4c0 [ 73.499901] ? __kernel_text_address+0xd/0x40 [ 73.504363] ? unwind_get_return_address+0x61/0xa0 [ 73.509261] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 73.514415] ? __save_stack_trace+0x61/0xd0 [ 73.518702] ? get_signal+0x73f/0x16d0 [ 73.522552] ? save_stack_trace+0x16/0x20 [ 73.526661] ? __lock_acquire+0x20fd/0x4620 [ 73.530947] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 73.536103] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 73.541255] ? save_stack_trace+0x16/0x20 [ 73.545367] ? __lock_acquire+0x20fd/0x4620 [ 73.549653] ? osq_unlock+0x350/0x350 [ 73.553417] ? save_stack_trace+0x16/0x20 [ 73.557529] ? __lock_is_held+0xbc/0x140 [ 73.561557] ? check_noncircular+0x20/0x20 [ 73.565763] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 73.570917] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 73.576072] ? find_held_lock+0x39/0x1d0 [ 73.580099] ? lock_downgrade+0x990/0x990 [ 73.584210] ? check_noncircular+0x20/0x20 [ 73.588410] lock_acquire+0x1d5/0x580 [ 73.592173] ? exit_pi_state_list+0x369/0x7a0 [ 73.596632] ? lock_release+0xd70/0xd70 [ 73.600570] ? do_raw_spin_trylock+0x190/0x190 [ 73.605115] ? find_held_lock+0x39/0x1d0 [ 73.609150] _raw_spin_lock_irq+0x5e/0x80 [ 73.613270] ? exit_pi_state_list+0x369/0x7a0 [ 73.617727] exit_pi_state_list+0x369/0x7a0 [ 73.622012] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 73.628032] ? lock_release+0xd70/0xd70 [ 73.631969] ? check_same_owner+0x320/0x320 [ 73.636252] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 73.641323] ? __might_sleep+0x95/0x190