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-386-2,10.128.0.54' (ECDSA) to the list of known hosts. 2017/10/04 01:46:25 parsed 1 programs 2017/10/04 01:46:25 executed programs: 0 syzkaller login: [ 32.785908] ================================================================== [ 32.793312] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 32.799944] Read of size 8 at addr ffff8801ce985b68 by task syz-executor3/3200 [ 32.807267] [ 32.808870] CPU: 0 PID: 3200 Comm: syz-executor3 Not tainted 4.14.0-rc3+ #23 [ 32.816017] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.825337] Call Trace: [ 32.827895] dump_stack+0x194/0x257 [ 32.831488] ? arch_local_irq_restore+0x53/0x53 [ 32.836124] ? show_regs_print_info+0x65/0x65 [ 32.840585] ? __kernel_text_address+0xd/0x40 [ 32.845049] ? __lock_acquire+0x407b/0x4620 [ 32.849340] print_address_description+0x73/0x250 [ 32.854151] ? __lock_acquire+0x407b/0x4620 [ 32.858438] kasan_report+0x25b/0x340 [ 32.862206] __asan_report_load8_noabort+0x14/0x20 [ 32.867115] __lock_acquire+0x407b/0x4620 [ 32.871232] ? unwind_dump+0x4c0/0x4c0 [ 32.875087] ? __kernel_text_address+0xd/0x40 [ 32.879549] ? unwind_get_return_address+0x61/0xa0 [ 32.884448] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.889604] ? __save_stack_trace+0x61/0xd0 [ 32.893892] ? get_signal+0x73f/0x16d0 [ 32.897747] ? save_stack_trace+0x16/0x20 [ 32.901862] ? __lock_acquire+0x20fd/0x4620 [ 32.906156] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.911314] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.916471] ? save_stack_trace+0x16/0x20 [ 32.920582] ? __lock_acquire+0x20fd/0x4620 [ 32.924872] ? osq_unlock+0x350/0x350 [ 32.928636] ? save_stack_trace+0x16/0x20 [ 32.932753] ? check_noncircular+0x20/0x20 [ 32.936955] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.942112] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.947267] ? __unwind_start+0x169/0x330 [ 32.951381] ? find_held_lock+0x39/0x1d0 [ 32.955413] ? lock_downgrade+0x990/0x990 [ 32.959529] ? check_noncircular+0x20/0x20 [ 32.963732] lock_acquire+0x1d5/0x580 [ 32.967500] ? exit_pi_state_list+0x369/0x7a0 [ 32.971963] ? lock_release+0xd70/0xd70 [ 32.975904] ? do_raw_spin_trylock+0x190/0x190 [ 32.980451] ? find_held_lock+0x39/0x1d0 [ 32.984483] _raw_spin_lock_irq+0x5e/0x80 [ 32.988594] ? exit_pi_state_list+0x369/0x7a0 [ 32.993053] exit_pi_state_list+0x369/0x7a0 [ 32.997342] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 33.003369] ? lock_release+0xd70/0xd70 [ 33.007313] ? check_same_owner+0x320/0x320 [ 33.011604] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 33.016677] ? __might_sleep+0x95/0x190 [ 33.020618] ? __might_fault+0x188/0x1d0 [ 33.024646] ? do_raw_spin_trylock+0x190/0x190 [ 33.029198] mm_release+0x46d/0x590 [ 33.032790] ? do_raw_spin_trylock+0x190/0x190 [ 33.037341] ? mm_access+0x140/0x140 [ 33.041022] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.045483] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.050465] ? trace_hardirqs_on+0xd/0x10 [ 33.054583] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.059045] ? acct_collect+0x637/0x800 [ 33.062986] do_exit+0x481/0x1af0 [ 33.066409] ? mm_update_next_owner+0x930/0x930 [ 33.071044] ? lock_downgrade+0x990/0x990 [ 33.075156] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 33.080487] ? futex_wait+0x3ad/0x990 [ 33.084254] ? do_raw_spin_trylock+0x190/0x190 [ 33.088807] ? fault_in_user_writeable+0x90/0x90 [ 33.093530] ? futex_wake+0x680/0x680 [ 33.097301] ? check_noncircular+0x20/0x20 [ 33.101505] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 33.106578] ? futex_wait+0x69e/0x990 [ 33.110351] ? futex_wait_setup+0x3d0/0x3d0 [ 33.114647] ? find_held_lock+0x39/0x1d0 [ 33.118692] ? lock_downgrade+0x990/0x990 [ 33.122807] ? recalc_sigpending_tsk+0x117/0x150 [ 33.127531] ? recalc_sigpending+0x103/0x160 [ 33.131908] ? recalc_sigpending_tsk+0x150/0x150 [ 33.136627] ? get_signal+0x2b2/0x16d0 [ 33.140483] do_group_exit+0x149/0x400 [ 33.144343] ? __lock_is_held+0xbc/0x140 [ 33.148377] ? SyS_exit+0x30/0x30 [ 33.151802] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.156269] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.161255] get_signal+0x73f/0x16d0 [ 33.164937] ? ptrace_notify+0x130/0x130 [ 33.168964] ? __schedule+0x8f3/0x2080 [ 33.172819] ? __sched_text_start+0x8/0x8 [ 33.176933] ? userfaultfd_unmap_complete+0x327/0x510 [ 33.182093] do_signal+0x94/0x1ee0 [ 33.185603] ? do_mmap+0x34f/0xd50 [ 33.189109] ? up_write+0x6b/0x120 [ 33.192615] ? setup_sigcontext+0x7d0/0x7d0 [ 33.196902] ? security_mmap_file+0x143/0x180 [ 33.201367] ? schedule+0xf5/0x430 [ 33.204875] ? vm_mmap_pgoff+0x13b/0x280 [ 33.208909] ? __schedule+0x2080/0x2080 [ 33.212851] ? vma_is_stack_for_current+0xa0/0xa0 [ 33.217663] ? find_held_lock+0x39/0x1d0 [ 33.221692] ? __compat_get_timespec+0xd9/0x120 [ 33.226349] ? exit_to_usermode_loop+0x8c/0x310 [ 33.230985] exit_to_usermode_loop+0x214/0x310 [ 33.235533] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 33.241037] ? lock_acquire+0x1d5/0x580 [ 33.244976] ? do_fast_syscall_32+0x158/0xf05 [ 33.249437] do_fast_syscall_32+0x83e/0xf05 [ 33.253727] ? compat_start_thread+0x80/0x80 [ 33.258101] ? do_int80_syscall_32+0x940/0x940 [ 33.262651] ? lockdep_sys_exit+0x47/0xf0 [ 33.266764] ? syscall_return_slowpath+0x2b3/0x510 [ 33.271661] ? finish_task_switch+0x1aa/0x740 [ 33.276121] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 33.281103] ? sysret32_from_system_call+0x5/0x3b [ 33.285911] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 33.290726] entry_SYSENTER_compat+0x51/0x60 [ 33.295102] RIP: 0023:0xf7f03c79 [ 33.298430] RSP: 002b:00000000f7eff12c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0 [ 33.306103] RAX: fffffffffffffe00 RBX: 0000000008128018 RCX: 0000000000000000 [ 33.313339] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 33.320576] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 33.327812] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 33.335048] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 33.342291] [ 33.343885] Allocated by task 3227: [ 33.347479] save_stack_trace+0x16/0x20 [ 33.351420] save_stack+0x43/0xd0 [ 33.354838] kasan_kmalloc+0xad/0xe0 [ 33.358518] kmem_cache_alloc_trace+0x136/0x750 [ 33.363151] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 33.368220] futex_requeue+0x1887/0x2370 [ 33.372242] do_futex+0x7f5/0x20d0 [ 33.375746] compat_SyS_futex+0x27f/0x380 [ 33.379858] do_fast_syscall_32+0x3f2/0xf05 [ 33.384144] entry_SYSENTER_compat+0x51/0x60 [ 33.388514] [ 33.390106] Freed by task 3216: [ 33.393350] save_stack_trace+0x16/0x20 [ 33.397290] save_stack+0x43/0xd0 [ 33.400708] kasan_slab_free+0x71/0xc0 [ 33.404560] kfree+0xca/0x250 [ 33.407631] put_pi_state+0x3f4/0x560 [ 33.411400] unqueue_me_pi+0x4a/0xc0 [ 33.415077] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 33.420839] do_futex+0x825/0x20d0 [ 33.424342] compat_SyS_futex+0x27f/0x380 [ 33.428455] do_fast_syscall_32+0x3f2/0xf05 [ 33.432742] entry_SYSENTER_compat+0x51/0x60 [ 33.437110] [ 33.438707] The buggy address belongs to the object at ffff8801ce985b40 [ 33.438707] which belongs to the cache kmalloc-256 of size 256 [ 33.451327] The buggy address is located 40 bytes inside of [ 33.451327] 256-byte region [ffff8801ce985b40, ffff8801ce985c40) [ 33.463076] The buggy address belongs to the page: [ 33.467972] page:ffffea00073a6140 count:1 mapcount:0 mapping:ffff8801ce985000 index:0xffff8801ce985640 [ 33.477379] flags: 0x200000000000100(slab) [ 33.481583] raw: 0200000000000100 ffff8801ce985000 ffff8801ce985640 0000000100000006 [ 33.489430] raw: ffffea00073aa3e0 ffffea00076444e0 ffff8801dac007c0 0000000000000000 [ 33.497285] page dumped because: kasan: bad access detected [ 33.502957] [ 33.504548] Memory state around the buggy address: [ 33.509439] ffff8801ce985a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.516776] ffff8801ce985a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.524100] >ffff8801ce985b00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 33.531423] ^ [ 33.538137] ffff8801ce985b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.545458] ffff8801ce985c00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 33.552780] ================================================================== [ 33.560102] Disabling lock debugging due to kernel taint [ 33.565515] Kernel panic - not syncing: panic_on_warn set ... [ 33.565515] [ 33.572844] CPU: 0 PID: 3200 Comm: syz-executor3 Tainted: G B 4.14.0-rc3+ #23 [ 33.581209] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.590527] Call Trace: [ 33.593083] dump_stack+0x194/0x257 [ 33.596677] ? arch_local_irq_restore+0x53/0x53 [ 33.601314] ? vprintk_default+0x28/0x30 [ 33.605341] ? __lock_acquire+0x3ff0/0x4620 [ 33.609631] panic+0x1e4/0x417 [ 33.612789] ? __warn+0x1d9/0x1d9 [ 33.616209] ? __lock_acquire+0x407b/0x4620 [ 33.620496] kasan_end_report+0x50/0x50 [ 33.624435] kasan_report+0x144/0x340 [ 33.628198] __asan_report_load8_noabort+0x14/0x20 [ 33.633093] __lock_acquire+0x407b/0x4620 [ 33.637206] ? unwind_dump+0x4c0/0x4c0 [ 33.641060] ? __kernel_text_address+0xd/0x40 [ 33.645519] ? unwind_get_return_address+0x61/0xa0 [ 33.650418] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.655573] ? __save_stack_trace+0x61/0xd0 [ 33.659865] ? get_signal+0x73f/0x16d0 [ 33.663717] ? save_stack_trace+0x16/0x20 [ 33.667831] ? __lock_acquire+0x20fd/0x4620 [ 33.672121] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.677277] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.682431] ? save_stack_trace+0x16/0x20 [ 33.686549] ? __lock_acquire+0x20fd/0x4620 [ 33.690835] ? osq_unlock+0x350/0x350 [ 33.694601] ? save_stack_trace+0x16/0x20 [ 33.698719] ? check_noncircular+0x20/0x20 [ 33.702920] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.708077] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.713232] ? __unwind_start+0x169/0x330 [ 33.717346] ? find_held_lock+0x39/0x1d0 [ 33.721373] ? lock_downgrade+0x990/0x990 [ 33.725485] ? check_noncircular+0x20/0x20 [ 33.729689] lock_acquire+0x1d5/0x580 [ 33.733458] ? exit_pi_state_list+0x369/0x7a0 [ 33.737920] ? lock_release+0xd70/0xd70 [ 33.741858] ? do_raw_spin_trylock+0x190/0x190 [ 33.746402] ? find_held_lock+0x39/0x1d0 [ 33.750434] _raw_spin_lock_irq+0x5e/0x80 [ 33.754546] ? exit_pi_state_list+0x369/0x7a0 [ 33.759004] exit_pi_state_list+0x369/0x7a0 [ 33.763294] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 33.769317] ? lock_release+0xd70/0xd70 [ 33.773258] ? check_same_owner+0x320/0x320 [ 33.777544] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 33.782616] ? __might_sleep+0x95/0x190