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-mmots-kasan-gce-1,10.128.15.210' (ECDSA) to the list of known hosts. 2017/09/30 22:00:45 parsed 1 programs 2017/09/30 22:00:45 executed programs: 0 2017/09/30 22:00:50 executed programs: 102 2017/09/30 22:00:55 executed programs: 206 syzkaller login: [ 45.375752] ================================================================== [ 45.383141] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 45.389775] Read of size 8 at addr ffff8801ca21b928 by task syz-executor0/4086 [ 45.397097] [ 45.398695] CPU: 1 PID: 4086 Comm: syz-executor0 Not tainted 4.14.0-rc2-mm1+ #11 [ 45.406209] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.415529] Call Trace: [ 45.418087] dump_stack+0x194/0x257 [ 45.421681] ? arch_local_irq_restore+0x53/0x53 [ 45.426316] ? show_regs_print_info+0x65/0x65 [ 45.430786] ? __kernel_text_address+0xd/0x40 [ 45.435247] ? __lock_acquire+0x407b/0x4620 [ 45.439536] print_address_description+0x73/0x250 [ 45.444341] ? __lock_acquire+0x407b/0x4620 [ 45.448626] kasan_report+0x25b/0x340 [ 45.452390] __asan_report_load8_noabort+0x14/0x20 [ 45.457282] __lock_acquire+0x407b/0x4620 [ 45.461393] ? unwind_dump+0x4c0/0x4c0 [ 45.465243] ? __unwind_start+0x169/0x330 [ 45.469353] ? __kernel_text_address+0xd/0x40 [ 45.473814] ? unwind_get_return_address+0x61/0xa0 [ 45.478712] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.483864] ? unwind_get_return_address+0x61/0xa0 [ 45.488756] ? __save_stack_trace+0x61/0xd0 [ 45.493043] ? get_signal+0x73f/0x16d0 [ 45.496894] ? save_stack_trace+0x16/0x20 [ 45.501004] ? __lock_acquire+0x20fd/0x4620 [ 45.505289] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.510444] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 45.515611] ? __bpf_address_lookup+0x2b0/0x2b0 [ 45.520245] ? osq_unlock+0x350/0x350 [ 45.524009] ? lock_release+0xd70/0xd70 [ 45.527950] ? __free_insn_slot+0x5c0/0x5c0 [ 45.532236] ? check_noncircular+0x20/0x20 [ 45.536437] ? is_bpf_text_address+0xa4/0x120 [ 45.540893] ? kernel_text_address+0x102/0x140 [ 45.545437] ? __kernel_text_address+0xd/0x40 [ 45.549896] ? find_held_lock+0x39/0x1d0 [ 45.553924] ? lock_downgrade+0x990/0x990 [ 45.558036] ? check_noncircular+0x20/0x20 [ 45.562231] ? kasan_kmalloc+0xad/0xe0 [ 45.566084] lock_acquire+0x1d5/0x580 [ 45.569850] ? exit_pi_state_list+0x369/0x7a0 [ 45.574310] ? lock_release+0xd70/0xd70 [ 45.578247] ? do_raw_spin_trylock+0x190/0x190 [ 45.582792] ? find_held_lock+0x39/0x1d0 [ 45.586823] _raw_spin_lock_irq+0x5e/0x80 [ 45.590936] ? exit_pi_state_list+0x369/0x7a0 [ 45.595396] exit_pi_state_list+0x369/0x7a0 [ 45.599686] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 45.605709] ? lock_release+0xd70/0xd70 [ 45.609655] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 45.615509] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 45.620578] ? __might_sleep+0x95/0x190 [ 45.624517] ? __might_fault+0x188/0x1d0 [ 45.628545] ? do_raw_spin_trylock+0x190/0x190 [ 45.633102] mm_release+0x46d/0x590 [ 45.636693] ? do_raw_spin_trylock+0x190/0x190 [ 45.641238] ? mm_access+0x140/0x140 [ 45.644916] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 45.649897] ? trace_hardirqs_on+0xd/0x10 [ 45.654011] ? _raw_spin_unlock_irq+0x27/0x70 [ 45.658471] ? acct_collect+0x637/0x800 [ 45.662408] do_exit+0x481/0x1b00 [ 45.665826] ? mm_update_next_owner+0x930/0x930 [ 45.670460] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 45.676307] ? find_held_lock+0x39/0x1d0 [ 45.680333] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 45.685665] ? check_noncircular+0x20/0x20 [ 45.689865] ? fault_in_user_writeable+0x90/0x90 [ 45.694586] ? futex_wake+0x680/0x680 [ 45.698352] ? find_held_lock+0x39/0x1d0 [ 45.702382] ? lock_downgrade+0x990/0x990 [ 45.706499] ? recalc_sigpending_tsk+0x117/0x150 [ 45.711219] ? recalc_sigpending+0x103/0x160 [ 45.715590] ? recalc_sigpending_tsk+0x150/0x150 [ 45.720307] ? get_signal+0x2b2/0x16d0 [ 45.724158] do_group_exit+0x149/0x400 [ 45.728020] ? __lock_is_held+0xbc/0x140 [ 45.732044] ? SyS_exit+0x30/0x30 [ 45.735462] ? _raw_spin_unlock_irq+0x27/0x70 [ 45.739921] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 45.744906] get_signal+0x73f/0x16d0 [ 45.748592] ? ptrace_notify+0x130/0x130 [ 45.752616] ? vma_wants_writenotify+0x3b0/0x3b0 [ 45.757337] ? exit_robust_list+0x240/0x240 [ 45.761624] ? lock_downgrade+0x990/0x990 [ 45.765746] ? SyS_brk+0x6f0/0x6f0 [ 45.769249] do_signal+0x94/0x1ee0 [ 45.772756] ? arch_get_unmapped_area+0x750/0x750 [ 45.777560] ? lock_acquire+0x1d5/0x580 [ 45.781498] ? find_held_lock+0x39/0x1d0 [ 45.785523] ? setup_sigcontext+0x7d0/0x7d0 [ 45.789817] ? lock_downgrade+0x990/0x990 [ 45.793939] ? down_write+0x120/0x120 [ 45.797707] ? lock_release+0xd70/0xd70 [ 45.801647] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 45.807501] ? vm_mmap_pgoff+0x1fc/0x280 [ 45.811613] ? exit_to_usermode_loop+0x8c/0x310 [ 45.816251] exit_to_usermode_loop+0x214/0x310 [ 45.820799] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 45.826302] ? kasan_check_write+0x14/0x20 [ 45.830503] syscall_return_slowpath+0x42f/0x510 [ 45.835229] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 45.840224] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 45.845118] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 45.850097] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 45.854818] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 45.859537] RIP: 0033:0x4520a9 [ 45.862691] RSP: 002b:00007f38a7886cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 45.870363] RAX: fffffffffffffe00 RBX: 0000000000718028 RCX: 00000000004520a9 [ 45.877596] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718028 [ 45.884831] RBP: 0000000000718000 R08: 0000000000000000 R09: 0000000000000000 [ 45.892067] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 45.899299] R13: 0000000000a6f7ef R14: 00007f38a78879c0 R15: 0000000000000000 [ 45.906536] [ 45.908131] Allocated by task 4088: [ 45.911728] save_stack_trace+0x16/0x20 [ 45.915663] save_stack+0x43/0xd0 [ 45.919086] kasan_kmalloc+0xad/0xe0 [ 45.922763] kmem_cache_alloc_trace+0x136/0x750 [ 45.927395] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 45.932459] futex_requeue+0x1887/0x2370 [ 45.936483] do_futex+0x7f5/0x20d0 [ 45.939985] SyS_futex+0x260/0x390 [ 45.943491] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 45.948205] [ 45.949796] Freed by task 4087: [ 45.953039] save_stack_trace+0x16/0x20 [ 45.956976] save_stack+0x43/0xd0 [ 45.960391] kasan_slab_free+0x71/0xc0 [ 45.964252] kfree+0xca/0x250 [ 45.967320] put_pi_state+0x3f4/0x560 [ 45.971082] unqueue_me_pi+0x4a/0xc0 [ 45.974757] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 45.980521] do_futex+0x825/0x20d0 [ 45.984022] SyS_futex+0x260/0x390 [ 45.987526] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 45.992241] [ 45.993832] The buggy address belongs to the object at ffff8801ca21b900 [ 45.993832] which belongs to the cache kmalloc-256 of size 256 [ 46.006452] The buggy address is located 40 bytes inside of [ 46.006452] 256-byte region [ffff8801ca21b900, ffff8801ca21ba00) [ 46.018288] The buggy address belongs to the page: [ 46.023184] page:ffffea00072886c0 count:1 mapcount:0 mapping:ffff8801ca21b040 index:0x0 [ 46.031288] flags: 0x200000000000100(slab) [ 46.035488] raw: 0200000000000100 ffff8801ca21b040 0000000000000000 000000010000000c [ 46.043331] raw: ffffea00072ba220 ffffea0007310ca0 ffff8801dac007c0 0000000000000000 [ 46.051173] page dumped because: kasan: bad access detected [ 46.056843] [ 46.058433] Memory state around the buggy address: [ 46.063323] ffff8801ca21b800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 46.070645] ffff8801ca21b880: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 46.077965] >ffff8801ca21b900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 46.085284] ^ [ 46.089916] ffff8801ca21b980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 46.097244] ffff8801ca21ba00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 46.104564] ================================================================== [ 46.111884] Disabling lock debugging due to kernel taint [ 46.117297] Kernel panic - not syncing: panic_on_warn set ... [ 46.117297] [ 46.124625] CPU: 1 PID: 4086 Comm: syz-executor0 Tainted: G B 4.14.0-rc2-mm1+ #11 [ 46.133334] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.142652] Call Trace: [ 46.145210] dump_stack+0x194/0x257 [ 46.148800] ? arch_local_irq_restore+0x53/0x53 [ 46.153432] ? vprintk_default+0x28/0x30 [ 46.157471] ? __lock_acquire+0x4060/0x4620 [ 46.161756] panic+0x1e4/0x41c [ 46.164913] ? refcount_error_report+0x214/0x214 [ 46.169634] ? __lock_acquire+0x407b/0x4620 [ 46.173920] kasan_end_report+0x50/0x50 [ 46.177858] kasan_report+0x144/0x340 [ 46.181629] __asan_report_load8_noabort+0x14/0x20 [ 46.186523] __lock_acquire+0x407b/0x4620 [ 46.190638] ? unwind_dump+0x4c0/0x4c0 [ 46.194489] ? __unwind_start+0x169/0x330 [ 46.198610] ? __kernel_text_address+0xd/0x40 [ 46.203072] ? unwind_get_return_address+0x61/0xa0 [ 46.207965] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 46.213116] ? unwind_get_return_address+0x61/0xa0 [ 46.218009] ? __save_stack_trace+0x61/0xd0 [ 46.222295] ? get_signal+0x73f/0x16d0 [ 46.226151] ? save_stack_trace+0x16/0x20 [ 46.230263] ? __lock_acquire+0x20fd/0x4620 [ 46.234548] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 46.239704] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 46.244859] ? __bpf_address_lookup+0x2b0/0x2b0 [ 46.249491] ? osq_unlock+0x350/0x350 [ 46.253252] ? lock_release+0xd70/0xd70 [ 46.257189] ? __free_insn_slot+0x5c0/0x5c0 [ 46.261476] ? check_noncircular+0x20/0x20 [ 46.265677] ? is_bpf_text_address+0xa4/0x120 [ 46.270136] ? kernel_text_address+0x102/0x140 [ 46.274681] ? __kernel_text_address+0xd/0x40 [ 46.279148] ? find_held_lock+0x39/0x1d0 [ 46.283176] ? lock_downgrade+0x990/0x990 [ 46.287305] ? check_noncircular+0x20/0x20 [ 46.291505] ? kasan_kmalloc+0xad/0xe0 [ 46.295357] lock_acquire+0x1d5/0x580 [ 46.299123] ? exit_pi_state_list+0x369/0x7a0 [ 46.303585] ? lock_release+0xd70/0xd70 [ 46.307522] ? do_raw_spin_trylock+0x190/0x190 [ 46.312072] ? find_held_lock+0x39/0x1d0 [ 46.316108] _raw_spin_lock_irq+0x5e/0x80 [ 46.320219] ? exit_pi_state_list+0x369/0x7a0 [ 46.324678] exit_pi_state_list+0x369/0x7a0 [ 46.328965] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 46.334987] ? lock_release+0xd70/0xd70 [ 46.338928] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 46.344775] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 46.349856] ? __might_sleep+0x95/0x190 [ 46.353793] ? __might_fault+0x188/0x1d0 [ 46.357819] ? do_raw_spin_trylock+0x190/0x190 [ 46.362367] mm_release+0x46d/0x590 [ 46.365960] ? do_raw_spin_trylock+0x190/0x190 [ 46.370505] ? mm_access+0x140/0x140 [ 46.374187] ? trace_hardirqs_on_caller+0x421/0x5c0