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-next-kasan-gce-6,10.128.15.209' (ECDSA) to the list of known hosts. 2017/10/01 10:23:12 parsed 1 programs 2017/10/01 10:23:12 executed programs: 0 syzkaller login: [ 33.982405] ================================================================== [ 33.989799] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 33.996430] Read of size 8 at addr ffff8801cb297de8 by task syz-executor1/4242 [ 34.003754] [ 34.005360] CPU: 0 PID: 4242 Comm: syz-executor1 Not tainted 4.14.0-rc2-next-20170929+ #32 [ 34.013735] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.023060] Call Trace: [ 34.025617] dump_stack+0x194/0x257 [ 34.029215] ? arch_local_irq_restore+0x53/0x53 [ 34.033859] ? show_regs_print_info+0x65/0x65 [ 34.038330] ? __kernel_text_address+0xd/0x40 [ 34.042803] ? __lock_acquire+0x407b/0x4620 [ 34.047101] print_address_description+0x73/0x250 [ 34.051917] ? __lock_acquire+0x407b/0x4620 [ 34.056203] kasan_report+0x25b/0x340 [ 34.059968] __asan_report_load8_noabort+0x14/0x20 [ 34.064863] __lock_acquire+0x407b/0x4620 [ 34.068981] ? unwind_dump+0x4c0/0x4c0 [ 34.072849] ? __unwind_start+0x169/0x330 [ 34.076976] ? __kernel_text_address+0xd/0x40 [ 34.081443] ? unwind_get_return_address+0x61/0xa0 [ 34.086341] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.091501] ? unwind_get_return_address+0x61/0xa0 [ 34.096403] ? __save_stack_trace+0x61/0xd0 [ 34.100690] ? get_signal+0x73f/0x16d0 [ 34.104542] ? save_stack_trace+0x16/0x20 [ 34.108654] ? __lock_acquire+0x20fd/0x4620 [ 34.112941] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.118098] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.123253] ? save_stack_trace+0x16/0x20 [ 34.127364] ? __lock_acquire+0x20fd/0x4620 [ 34.131652] ? osq_unlock+0x350/0x350 [ 34.135415] ? save_stack_trace+0x16/0x20 [ 34.139537] ? lock_release+0xd70/0xd70 [ 34.143484] ? check_noncircular+0x20/0x20 [ 34.147689] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.152852] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.158021] ? find_held_lock+0x39/0x1d0 [ 34.162059] ? lock_downgrade+0x990/0x990 [ 34.166178] ? check_noncircular+0x20/0x20 [ 34.170378] lock_acquire+0x1d5/0x580 [ 34.174144] ? exit_pi_state_list+0x369/0x7a0 [ 34.178604] ? lock_release+0xd70/0xd70 [ 34.182542] ? do_raw_spin_trylock+0x190/0x190 [ 34.187089] ? find_held_lock+0x39/0x1d0 [ 34.191126] _raw_spin_lock_irq+0x5e/0x80 [ 34.195237] ? exit_pi_state_list+0x369/0x7a0 [ 34.199695] exit_pi_state_list+0x369/0x7a0 [ 34.203983] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 34.210011] ? lock_release+0xd70/0xd70 [ 34.213958] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 34.219809] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 34.224883] ? __might_sleep+0x95/0x190 [ 34.228822] ? __might_fault+0x188/0x1d0 [ 34.232850] ? do_raw_spin_trylock+0x190/0x190 [ 34.237406] mm_release+0x46d/0x590 [ 34.241003] ? do_raw_spin_trylock+0x190/0x190 [ 34.245560] ? mm_access+0x140/0x140 [ 34.249247] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.253716] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.258706] ? trace_hardirqs_on+0xd/0x10 [ 34.262818] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.267277] ? acct_collect+0x637/0x800 [ 34.271222] do_exit+0x481/0x1b00 [ 34.274647] ? mm_update_next_owner+0x930/0x930 [ 34.279283] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 34.285140] ? find_held_lock+0x39/0x1d0 [ 34.289174] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 34.294505] ? check_noncircular+0x20/0x20 [ 34.298720] ? fault_in_user_writeable+0x90/0x90 [ 34.303446] ? futex_wake+0x680/0x680 [ 34.307218] ? find_held_lock+0x39/0x1d0 [ 34.311247] ? lock_downgrade+0x990/0x990 [ 34.315360] ? recalc_sigpending_tsk+0x117/0x150 [ 34.320082] ? recalc_sigpending+0x103/0x160 [ 34.324454] ? recalc_sigpending_tsk+0x150/0x150 [ 34.329174] ? get_signal+0x2b2/0x16d0 [ 34.333040] do_group_exit+0x149/0x400 [ 34.336900] ? __lock_is_held+0xbc/0x140 [ 34.340925] ? SyS_exit+0x30/0x30 [ 34.344343] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.348805] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.353791] get_signal+0x73f/0x16d0 [ 34.357480] ? ptrace_notify+0x130/0x130 [ 34.361510] ? vma_wants_writenotify+0x3b0/0x3b0 [ 34.366238] ? exit_robust_list+0x240/0x240 [ 34.370536] ? lock_downgrade+0x990/0x990 [ 34.374657] ? SyS_brk+0x6f0/0x6f0 [ 34.378171] do_signal+0x94/0x1ee0 [ 34.381685] ? arch_get_unmapped_area+0x750/0x750 [ 34.386496] ? lock_acquire+0x1d5/0x580 [ 34.390442] ? vm_mmap_pgoff+0x198/0x280 [ 34.394483] ? userfaultfd_unmap_complete+0x327/0x510 [ 34.399643] ? setup_sigcontext+0x7d0/0x7d0 [ 34.403929] ? userfaultfd_unmap_prep+0x540/0x540 [ 34.408739] ? do_mmap+0x34f/0xd50 [ 34.412250] ? up_write+0x6b/0x120 [ 34.415763] ? down_write+0x120/0x120 [ 34.419536] ? security_mmap_file+0x143/0x180 [ 34.423996] ? vm_mmap_pgoff+0x1fc/0x280 [ 34.428031] ? exit_to_usermode_loop+0x8c/0x310 [ 34.432669] exit_to_usermode_loop+0x214/0x310 [ 34.437217] ? vma_is_stack_for_current+0xa0/0xa0 [ 34.442034] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 34.447538] ? kasan_check_write+0x14/0x20 [ 34.451744] syscall_return_slowpath+0x42f/0x510 [ 34.456466] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 34.461450] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 34.466696] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.471683] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 34.476424] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 34.481155] RIP: 0033:0x4520a9 [ 34.484311] RSP: 002b:00007f6083aaccf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 34.491988] RAX: fffffffffffffe00 RBX: 0000000000718188 RCX: 00000000004520a9 [ 34.499668] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718188 [ 34.506905] RBP: 0000000000718160 R08: 0000000000000000 R09: 0000000000000000 [ 34.514142] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 34.521377] R13: 00007ffe278fa0ef R14: 00007f6083aad9c0 R15: 0000000000000003 [ 34.528618] [ 34.530211] Allocated by task 4257: [ 34.533807] save_stack_trace+0x16/0x20 [ 34.537755] save_stack+0x43/0xd0 [ 34.541183] kasan_kmalloc+0xad/0xe0 [ 34.544868] kmem_cache_alloc_trace+0x136/0x750 [ 34.549504] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 34.554573] futex_requeue+0x1887/0x2370 [ 34.558600] do_futex+0x7f5/0x20d0 [ 34.562113] SyS_futex+0x260/0x390 [ 34.565622] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 34.570336] [ 34.571929] Freed by task 4234: [ 34.575173] save_stack_trace+0x16/0x20 [ 34.579121] save_stack+0x43/0xd0 [ 34.582543] kasan_slab_free+0x71/0xc0 [ 34.586413] kfree+0xca/0x250 [ 34.589499] put_pi_state+0x3f4/0x560 [ 34.593265] unqueue_me_pi+0x4a/0xc0 [ 34.596942] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 34.602701] do_futex+0x825/0x20d0 [ 34.606206] SyS_futex+0x260/0x390 [ 34.609712] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 34.614428] [ 34.616028] The buggy address belongs to the object at ffff8801cb297dc0 [ 34.616028] which belongs to the cache kmalloc-256 of size 256 [ 34.628652] The buggy address is located 40 bytes inside of [ 34.628652] 256-byte region [ffff8801cb297dc0, ffff8801cb297ec0) [ 34.640401] The buggy address belongs to the page: [ 34.645293] page:ffffea00072ca5c0 count:1 mapcount:0 mapping:ffff8801cb297000 index:0x0 [ 34.653399] flags: 0x200000000000100(slab) [ 34.657605] raw: 0200000000000100 ffff8801cb297000 0000000000000000 000000010000000c [ 34.665449] raw: ffffea000730d220 ffffea00072bb720 ffff8801dac007c0 0000000000000000 [ 34.673290] page dumped because: kasan: bad access detected [ 34.678959] [ 34.680551] Memory state around the buggy address: [ 34.685444] ffff8801cb297c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.692764] ffff8801cb297d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.700087] >ffff8801cb297d80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 34.707410] ^ [ 34.714125] ffff8801cb297e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.721453] ffff8801cb297e80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 34.728780] ================================================================== [ 34.736100] Disabling lock debugging due to kernel taint [ 34.741510] Kernel panic - not syncing: panic_on_warn set ... [ 34.741510] [ 34.748836] CPU: 0 PID: 4242 Comm: syz-executor1 Tainted: G B 4.14.0-rc2-next-20170929+ #32 [ 34.758415] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.767739] Call Trace: [ 34.770294] dump_stack+0x194/0x257 [ 34.773885] ? arch_local_irq_restore+0x53/0x53 [ 34.778520] ? vprintk_default+0x28/0x30 [ 34.782548] ? __lock_acquire+0x4000/0x4620 [ 34.786834] panic+0x1e4/0x41c [ 34.789991] ? refcount_error_report+0x214/0x214 [ 34.794718] ? __lock_acquire+0x407b/0x4620 [ 34.799004] kasan_end_report+0x50/0x50 [ 34.802947] kasan_report+0x144/0x340 [ 34.806714] __asan_report_load8_noabort+0x14/0x20 [ 34.811607] __lock_acquire+0x407b/0x4620 [ 34.815727] ? unwind_dump+0x4c0/0x4c0 [ 34.819580] ? __unwind_start+0x169/0x330 [ 34.823693] ? __kernel_text_address+0xd/0x40 [ 34.828153] ? unwind_get_return_address+0x61/0xa0 [ 34.833050] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.838203] ? unwind_get_return_address+0x61/0xa0 [ 34.843098] ? __save_stack_trace+0x61/0xd0 [ 34.847382] ? get_signal+0x73f/0x16d0 [ 34.851233] ? save_stack_trace+0x16/0x20 [ 34.855345] ? __lock_acquire+0x20fd/0x4620 [ 34.859631] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.864797] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.869952] ? save_stack_trace+0x16/0x20 [ 34.874063] ? __lock_acquire+0x20fd/0x4620 [ 34.878348] ? osq_unlock+0x350/0x350 [ 34.882111] ? save_stack_trace+0x16/0x20 [ 34.886222] ? lock_release+0xd70/0xd70 [ 34.890162] ? check_noncircular+0x20/0x20 [ 34.894361] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.899515] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.904671] ? find_held_lock+0x39/0x1d0 [ 34.908698] ? lock_downgrade+0x990/0x990 [ 34.912809] ? check_noncircular+0x20/0x20 [ 34.917010] lock_acquire+0x1d5/0x580 [ 34.920778] ? exit_pi_state_list+0x369/0x7a0 [ 34.925236] ? lock_release+0xd70/0xd70 [ 34.929176] ? do_raw_spin_trylock+0x190/0x190 [ 34.933721] ? find_held_lock+0x39/0x1d0 [ 34.937751] _raw_spin_lock_irq+0x5e/0x80 [ 34.941862] ? exit_pi_state_list+0x369/0x7a0 [ 34.946319] exit_pi_state_list+0x369/0x7a0 [ 34.950607] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 34.956629] ? lock_release+0xd70/0xd70 [ 34.960569] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 34.966425] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 34.971497] ? __might_sleep+0x95/0x190 [ 34.975436] ? __might_fault+0x188/0x1d0 [ 34.979471] ? do_raw_spin_trylock+0x190/0x190