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-2,10.128.0.18' (ECDSA) to the list of known hosts. 2017/09/29 16:15:58 parsed 1 programs 2017/09/29 16:15:58 executed programs: 0 syzkaller login: [ 59.620166] ================================================================== [ 59.621333] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 59.622537] Read of size 8 at addr ffff8801c9655a28 by task syz-executor5/4446 [ 59.623886] [ 59.624306] CPU: 0 PID: 4446 Comm: syz-executor5 Not tainted 4.14.0-rc2-mm1+ #10 [ 59.625302] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.626860] Call Trace: [ 59.627402] dump_stack+0x194/0x257 [ 59.628028] ? arch_local_irq_restore+0x53/0x53 [ 59.628673] ? show_regs_print_info+0x65/0x65 [ 59.629274] ? __kernel_text_address+0xd/0x40 [ 59.629884] ? __lock_acquire+0x407b/0x4620 [ 59.630513] print_address_description+0x73/0x250 [ 59.631175] ? __lock_acquire+0x407b/0x4620 [ 59.631790] kasan_report+0x25b/0x340 [ 59.632360] __asan_report_load8_noabort+0x14/0x20 [ 59.633027] __lock_acquire+0x407b/0x4620 [ 59.633631] ? unwind_dump+0x4c0/0x4c0 [ 59.634148] ? __unwind_start+0x169/0x330 [ 59.634730] ? __kernel_text_address+0xd/0x40 [ 59.635327] ? unwind_get_return_address+0x61/0xa0 [ 59.636031] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 59.636726] ? unwind_get_return_address+0x61/0xa0 [ 59.637403] ? __save_stack_trace+0x61/0xd0 [ 59.637988] ? get_signal+0x73f/0x16d0 [ 59.638542] ? save_stack_trace+0x16/0x20 [ 59.639103] ? __lock_acquire+0x20fd/0x4620 [ 59.639687] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 59.640945] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 59.646110] ? save_stack_trace+0x16/0x20 [ 59.650235] ? __lock_acquire+0x20fd/0x4620 [ 59.654537] ? osq_unlock+0x350/0x350 [ 59.658311] ? save_stack_trace+0x16/0x20 [ 59.662433] ? save_stack_trace+0x16/0x20 [ 59.666566] ? check_noncircular+0x20/0x20 [ 59.670788] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 59.675969] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 59.681136] ? unwind_get_return_address+0x61/0xa0 [ 59.686040] ? find_held_lock+0x39/0x1d0 [ 59.690091] ? lock_downgrade+0x990/0x990 [ 59.694216] ? check_noncircular+0x20/0x20 [ 59.698433] lock_acquire+0x1d5/0x580 [ 59.702314] ? exit_pi_state_list+0x369/0x7a0 [ 59.706792] ? lock_release+0xd70/0xd70 [ 59.710740] ? do_raw_spin_trylock+0x190/0x190 [ 59.715301] ? find_held_lock+0x39/0x1d0 [ 59.719357] _raw_spin_lock_irq+0x5e/0x80 [ 59.723495] ? exit_pi_state_list+0x369/0x7a0 [ 59.727973] exit_pi_state_list+0x369/0x7a0 [ 59.732282] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 59.738332] ? lock_release+0xd70/0xd70 [ 59.742278] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 59.748144] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 59.753228] ? __might_sleep+0x95/0x190 [ 59.757182] ? __might_fault+0x188/0x1d0 [ 59.761229] ? do_raw_spin_trylock+0x190/0x190 [ 59.765803] mm_release+0x46d/0x590 [ 59.769415] ? mm_access+0x140/0x140 [ 59.773114] ? _raw_spin_unlock_irq+0x27/0x70 [ 59.777601] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 59.782612] ? trace_hardirqs_on+0xd/0x10 [ 59.786734] ? _raw_spin_unlock_irq+0x27/0x70 [ 59.791202] ? acct_collect+0x637/0x800 [ 59.795154] do_exit+0x481/0x1b00 [ 59.798579] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 59.803659] ? trace_hardirqs_on_caller+0x3b0/0x5c0 [ 59.808647] ? mm_update_next_owner+0x930/0x930 [ 59.813298] ? trace_hardirqs_on+0xd/0x10 [ 59.817435] ? hrtimer_try_to_cancel+0x9a/0x5c0 [ 59.822084] ? __hrtimer_get_remaining+0x1c0/0x1c0 [ 59.827002] ? get_futex_value_locked+0xc3/0xf0 [ 59.831651] ? do_raw_spin_trylock+0x190/0x190 [ 59.836213] ? futex_wake+0x680/0x680 [ 59.839988] ? memset+0x31/0x40 [ 59.843257] ? check_noncircular+0x20/0x20 [ 59.847469] ? hrtimer_cancel+0x2e/0x40 [ 59.851419] ? futex_wait_requeue_pi.constprop.19+0x8a8/0x1300 [ 59.857381] ? futex_requeue+0x2370/0x2370 [ 59.861590] ? find_held_lock+0x39/0x1d0 [ 59.865627] ? lock_downgrade+0x990/0x990 [ 59.869763] ? recalc_sigpending_tsk+0x117/0x150 [ 59.874498] ? recalc_sigpending+0x103/0x160 [ 59.878879] ? recalc_sigpending_tsk+0x150/0x150 [ 59.883611] ? get_signal+0x2b2/0x16d0 [ 59.887477] do_group_exit+0x149/0x400 [ 59.891341] ? __lock_is_held+0xbc/0x140 [ 59.895381] ? SyS_exit+0x30/0x30 [ 59.898820] ? _raw_spin_unlock_irq+0x27/0x70 [ 59.903286] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 59.908280] get_signal+0x73f/0x16d0 [ 59.911978] ? ptrace_notify+0x130/0x130 [ 59.916030] ? __schedule+0x8f0/0x2070 [ 59.919918] ? exit_robust_list+0x240/0x240 [ 59.924237] ? check_noncircular+0x20/0x20 [ 59.928455] do_signal+0x94/0x1ee0 [ 59.931967] ? find_held_lock+0x39/0x1d0 [ 59.935997] ? setup_sigcontext+0x7d0/0x7d0 [ 59.940382] ? lock_downgrade+0x990/0x990 [ 59.944517] ? lock_release+0xd70/0xd70 [ 59.948463] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 59.954327] ? lock_acquire+0x1d5/0x580 [ 59.958282] ? finish_task_switch+0x1aa/0x740 [ 59.962754] ? exit_to_usermode_loop+0x8c/0x310 [ 59.967407] exit_to_usermode_loop+0x214/0x310 [ 59.971969] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 59.977491] ? kasan_check_write+0x14/0x20 [ 59.981707] syscall_return_slowpath+0x42f/0x510 [ 59.986440] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 59.991444] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 59.996355] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 60.001343] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 60.006071] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 60.010819] RIP: 0033:0x4520a9 [ 60.013995] RSP: 002b:00007f55eec44c08 EFLAGS: 00000216 ORIG_RAX: 00000000000000ca [ 60.021678] RAX: 0000000000000000 RBX: 0000000000718210 RCX: 00000000004520a9 [ 60.028919] RDX: 0000000000000004 RSI: 000080000000000b RDI: 000000002000cffc [ 60.036168] RBP: 00000000000008f0 R08: 0000000020048000 R09: 0000000000000000 [ 60.043420] R10: 0000000020edfff0 R11: 0000000000000216 R12: 00000000004b77c8 [ 60.050668] R13: 00000000ffffffff R14: 000000002000cffc R15: 000080000000000b [ 60.057936] [ 60.059544] Allocated by task 4473: [ 60.063161] save_stack_trace+0x16/0x20 [ 60.067132] save_stack+0x43/0xd0 [ 60.070568] kasan_kmalloc+0xad/0xe0 [ 60.074253] kmem_cache_alloc_trace+0x136/0x750 [ 60.078891] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 60.083962] futex_requeue+0x1887/0x2370 [ 60.088008] do_futex+0x7f5/0x20d0 [ 60.091529] SyS_futex+0x260/0x390 [ 60.095048] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 60.099783] [ 60.101388] Freed by task 4440: [ 60.104647] save_stack_trace+0x16/0x20 [ 60.108607] save_stack+0x43/0xd0 [ 60.112049] kasan_slab_free+0x71/0xc0 [ 60.115904] kfree+0xca/0x250 [ 60.118976] put_pi_state+0x3f4/0x560 [ 60.122752] unqueue_me_pi+0x4a/0xc0 [ 60.126448] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 60.132233] do_futex+0x825/0x20d0 [ 60.135758] SyS_futex+0x260/0x390 [ 60.139290] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 60.144031] [ 60.145646] The buggy address belongs to the object at ffff8801c9655a00 [ 60.145646] which belongs to the cache kmalloc-256 of size 256 [ 60.158294] The buggy address is located 40 bytes inside of [ 60.158294] 256-byte region [ffff8801c9655a00, ffff8801c9655b00) [ 60.170070] The buggy address belongs to the page: [ 60.174970] page:ffffea0007259540 count:1 mapcount:0 mapping:ffff8801c9655000 index:0x0 [ 60.183083] flags: 0x200000000000100(slab) [ 60.187304] raw: 0200000000000100 ffff8801c9655000 0000000000000000 000000010000000c [ 60.195164] raw: ffffea0007259420 ffffea0007240d60 ffff8801dac007c0 0000000000000000 [ 60.203015] page dumped because: kasan: bad access detected [ 60.208688] [ 60.210280] Memory state around the buggy address: [ 60.215175] ffff8801c9655900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.222503] ffff8801c9655980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 60.229828] >ffff8801c9655a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.237152] ^ [ 60.241786] ffff8801c9655a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.249110] ffff8801c9655b00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 60.256432] ================================================================== [ 60.263754] Disabling lock debugging due to kernel taint [ 60.269170] Kernel panic - not syncing: panic_on_warn set ... [ 60.269170] [ 60.276502] CPU: 0 PID: 4446 Comm: syz-executor5 Tainted: G B 4.14.0-rc2-mm1+ #10 [ 60.285221] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.294541] Call Trace: [ 60.297096] dump_stack+0x194/0x257 [ 60.300692] ? arch_local_irq_restore+0x53/0x53 [ 60.305341] ? vprintk_default+0x28/0x30 [ 60.309370] ? __lock_acquire+0x4020/0x4620 [ 60.313660] panic+0x1e4/0x417 [ 60.316818] ? __warn+0x1d9/0x1d9 [ 60.320241] ? __lock_acquire+0x407b/0x4620 [ 60.324530] kasan_end_report+0x50/0x50 [ 60.328469] kasan_report+0x144/0x340 [ 60.332240] __asan_report_load8_noabort+0x14/0x20 [ 60.337136] __lock_acquire+0x407b/0x4620 [ 60.341253] ? unwind_dump+0x4c0/0x4c0 [ 60.345104] ? __unwind_start+0x169/0x330 [ 60.349219] ? __kernel_text_address+0xd/0x40 [ 60.353682] ? unwind_get_return_address+0x61/0xa0 [ 60.358583] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 60.363747] ? unwind_get_return_address+0x61/0xa0 [ 60.368650] ? __save_stack_trace+0x61/0xd0 [ 60.372945] ? get_signal+0x73f/0x16d0 [ 60.376800] ? save_stack_trace+0x16/0x20 [ 60.380928] ? __lock_acquire+0x20fd/0x4620 [ 60.385219] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 60.390379] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 60.395535] ? save_stack_trace+0x16/0x20 [ 60.399648] ? __lock_acquire+0x20fd/0x4620 [ 60.403937] ? osq_unlock+0x350/0x350 [ 60.407704] ? save_stack_trace+0x16/0x20 [ 60.411819] ? save_stack_trace+0x16/0x20 [ 60.415934] ? check_noncircular+0x20/0x20 [ 60.420147] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 60.425303] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 60.430460] ? unwind_get_return_address+0x61/0xa0 [ 60.435358] ? find_held_lock+0x39/0x1d0 [ 60.439401] ? lock_downgrade+0x990/0x990 [ 60.443524] ? check_noncircular+0x20/0x20 [ 60.447726] lock_acquire+0x1d5/0x580 [ 60.451495] ? exit_pi_state_list+0x369/0x7a0 [ 60.455957] ? lock_release+0xd70/0xd70 [ 60.459896] ? do_raw_spin_trylock+0x190/0x190 [ 60.464446] ? find_held_lock+0x39/0x1d0 [ 60.468479] _raw_spin_lock_irq+0x5e/0x80 [ 60.472593] ? exit_pi_state_list+0x369/0x7a0 [ 60.477055] exit_pi_state_list+0x369/0x7a0 [ 60.481348] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 60.487375] ? lock_release+0xd70/0xd70 [ 60.491320] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 60.497175] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 60.502250] ? __might_sleep+0x95/0x190 [ 60.506198] ? __might_fault+0x188/0x1d0 [ 60.510228] ? do_raw_spin_trylock+0x190/0x190 [ 60.514788] mm_release+0x46d/0x590 [ 60.518381] ? mm_access+0x140/0x140 [ 60.522063] ? _raw_spin_unlock_irq+0x27/0x70 [ 60.526524] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 60.531508] ? trace_hardirqs_on+0xd/0x10 [ 60.535624] ? _raw_spin_unlock_irq+0x27/0x70 [ 60.540085] ? acct_collect+0x637/0x800 [ 60.544028] do_exit+0x481/0x1b00 [ 60.547449] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 60.552519] ? trace_hardirqs_on_caller+0x3b0/0x5c0 [ 60.557502] ? mm_update_next_owner+0x930/0x930 [ 60.562140] ? trace_hardirqs_on+0xd/0x10 [ 60.566256] ? hrtimer_try_to_cancel+0x9a/0x5c0 [ 60.570899] ? __hrtimer_get_remaining+0x1c0/0x1c0 [ 60.575795] ? get_futex_value_locked+0xc3/0xf0 [ 60.580432] ? do_raw_spin_trylock+0x190/0x190 [ 60.584983] ? futex_wake+0x680/0x680 [ 60.588757] ? memset+0x31/0x40 [ 60.592008] ? check_noncircular+0x20/0x20 [ 60.596221] ? hrtimer_cancel+0x2e/0x40 [ 60.600162] ? futex_wait_requeue_pi.constprop.19+0x8a8/0x1300 [ 60.606104] ? futex_requeue+0x2370/0x2370 [ 60.610317] ? find_held_lock+0x39/0x1d0 [ 60.614347] ? lock_downgrade+0x990/0x990 [ 60.618465] ? recalc_sigpending_tsk+0x117/0x150