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-7,10.128.0.55' (ECDSA) to the list of known hosts. 2017/10/01 20:51:16 parsed 1 programs 2017/10/01 20:51:16 executed programs: 0 syzkaller login: [ 33.892831] ================================================================== [ 33.900216] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 33.906847] Read of size 8 at addr ffff8801cded2328 by task syz-executor0/3322 [ 33.914168] [ 33.915763] CPU: 1 PID: 3322 Comm: syz-executor0 Not tainted 4.14.0-rc2-mm1+ #11 [ 33.923256] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.932572] Call Trace: [ 33.935126] dump_stack+0x194/0x257 [ 33.938730] ? arch_local_irq_restore+0x53/0x53 [ 33.943362] ? show_regs_print_info+0x65/0x65 [ 33.947822] ? __kernel_text_address+0xd/0x40 [ 33.952281] ? __lock_acquire+0x407b/0x4620 [ 33.956578] print_address_description+0x73/0x250 [ 33.961385] ? __lock_acquire+0x407b/0x4620 [ 33.965671] kasan_report+0x25b/0x340 [ 33.969436] __asan_report_load8_noabort+0x14/0x20 [ 33.974330] __lock_acquire+0x407b/0x4620 [ 33.978442] ? unwind_dump+0x4c0/0x4c0 [ 33.982291] ? __unwind_start+0x169/0x330 [ 33.986402] ? __kernel_text_address+0xd/0x40 [ 33.990859] ? unwind_get_return_address+0x61/0xa0 [ 33.995754] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.000907] ? unwind_get_return_address+0x61/0xa0 [ 34.005802] ? __save_stack_trace+0x61/0xd0 [ 34.010089] ? get_signal+0x73f/0x16d0 [ 34.013940] ? save_stack_trace+0x16/0x20 [ 34.018052] ? __lock_acquire+0x20fd/0x4620 [ 34.022339] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.027497] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.032650] ? __bpf_address_lookup+0x2b0/0x2b0 [ 34.037282] ? osq_unlock+0x350/0x350 [ 34.041046] ? lock_release+0xd70/0xd70 [ 34.044985] ? __free_insn_slot+0x5c0/0x5c0 [ 34.049274] ? check_noncircular+0x20/0x20 [ 34.053475] ? is_bpf_text_address+0xa4/0x120 [ 34.057936] ? kernel_text_address+0x102/0x140 [ 34.062483] ? __kernel_text_address+0xd/0x40 [ 34.066946] ? find_held_lock+0x39/0x1d0 [ 34.070974] ? lock_downgrade+0x990/0x990 [ 34.075094] ? check_noncircular+0x20/0x20 [ 34.079292] ? kasan_kmalloc+0xad/0xe0 [ 34.083148] lock_acquire+0x1d5/0x580 [ 34.086914] ? exit_pi_state_list+0x369/0x7a0 [ 34.091375] ? lock_release+0xd70/0xd70 [ 34.095316] ? do_raw_spin_trylock+0x190/0x190 [ 34.099860] ? find_held_lock+0x39/0x1d0 [ 34.103891] _raw_spin_lock_irq+0x5e/0x80 [ 34.108004] ? exit_pi_state_list+0x369/0x7a0 [ 34.112462] exit_pi_state_list+0x369/0x7a0 [ 34.116750] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 34.122772] ? lock_release+0xd70/0xd70 [ 34.126719] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 34.132571] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 34.137641] ? __might_sleep+0x95/0x190 [ 34.141578] ? __might_fault+0x188/0x1d0 [ 34.145603] ? do_raw_spin_trylock+0x190/0x190 [ 34.150150] mm_release+0x46d/0x590 [ 34.153740] ? do_raw_spin_trylock+0x190/0x190 [ 34.158285] ? mm_access+0x140/0x140 [ 34.161963] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.166942] ? trace_hardirqs_on+0xd/0x10 [ 34.171054] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.175514] ? acct_collect+0x637/0x800 [ 34.179452] do_exit+0x481/0x1b00 [ 34.182872] ? mm_update_next_owner+0x930/0x930 [ 34.187505] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 34.193788] ? find_held_lock+0x39/0x1d0 [ 34.197815] ? osq_unlock+0x350/0x350 [ 34.201580] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 34.206908] ? check_noncircular+0x20/0x20 [ 34.211111] ? fault_in_user_writeable+0x90/0x90 [ 34.215829] ? futex_wake+0x680/0x680 [ 34.219595] ? find_held_lock+0x39/0x1d0 [ 34.223621] ? lock_downgrade+0x990/0x990 [ 34.227735] ? recalc_sigpending_tsk+0x117/0x150 [ 34.232454] ? recalc_sigpending+0x103/0x160 [ 34.236827] ? recalc_sigpending_tsk+0x150/0x150 [ 34.241547] ? get_signal+0x2b2/0x16d0 [ 34.245400] do_group_exit+0x149/0x400 [ 34.249251] ? __lock_is_held+0xbc/0x140 [ 34.253290] ? SyS_exit+0x30/0x30 [ 34.256707] ? _raw_spin_unlock_irq+0x27/0x70 [ 34.261165] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.266145] get_signal+0x73f/0x16d0 [ 34.269822] ? ptrace_notify+0x130/0x130 [ 34.273847] ? vma_wants_writenotify+0x3b0/0x3b0 [ 34.278580] ? exit_robust_list+0x240/0x240 [ 34.282869] ? lock_downgrade+0x990/0x990 [ 34.286979] ? SyS_brk+0x6f0/0x6f0 [ 34.290487] do_signal+0x94/0x1ee0 [ 34.293990] ? arch_get_unmapped_area+0x750/0x750 [ 34.298795] ? lock_acquire+0x1d5/0x580 [ 34.302733] ? find_held_lock+0x39/0x1d0 [ 34.306759] ? setup_sigcontext+0x7d0/0x7d0 [ 34.311049] ? lock_downgrade+0x990/0x990 [ 34.315162] ? down_write+0x120/0x120 [ 34.318928] ? lock_release+0xd70/0xd70 [ 34.322866] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 34.328715] ? vm_mmap_pgoff+0x1fc/0x280 [ 34.332740] ? exit_to_usermode_loop+0x8c/0x310 [ 34.337373] exit_to_usermode_loop+0x214/0x310 [ 34.341919] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 34.347419] ? kasan_check_write+0x14/0x20 [ 34.351620] syscall_return_slowpath+0x42f/0x510 [ 34.356343] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 34.361324] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 34.366217] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 34.371197] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 34.375918] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 34.380637] RIP: 0033:0x4520a9 [ 34.383792] RSP: 002b:00007f2814f61cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 34.391463] RAX: fffffffffffffe00 RBX: 0000000000718028 RCX: 00000000004520a9 [ 34.398695] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718028 [ 34.405928] RBP: 0000000000718000 R08: 0000000000000000 R09: 0000000000000000 [ 34.413161] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 34.420396] R13: 0000000000a6f7ef R14: 00007f2814f629c0 R15: 0000000000000000 [ 34.427635] [ 34.429227] Allocated by task 3324: [ 34.432819] save_stack_trace+0x16/0x20 [ 34.436755] save_stack+0x43/0xd0 [ 34.440176] kasan_kmalloc+0xad/0xe0 [ 34.443855] kmem_cache_alloc_trace+0x136/0x750 [ 34.448485] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 34.453564] futex_requeue+0x1887/0x2370 [ 34.457588] do_futex+0x7f5/0x20d0 [ 34.461091] SyS_futex+0x260/0x390 [ 34.464594] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 34.469310] [ 34.470901] Freed by task 3323: [ 34.474142] save_stack_trace+0x16/0x20 [ 34.478080] save_stack+0x43/0xd0 [ 34.481494] kasan_slab_free+0x71/0xc0 [ 34.485343] kfree+0xca/0x250 [ 34.488413] put_pi_state+0x3f4/0x560 [ 34.492176] unqueue_me_pi+0x4a/0xc0 [ 34.495854] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 34.501615] do_futex+0x825/0x20d0 [ 34.505119] SyS_futex+0x260/0x390 [ 34.508624] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 34.513340] [ 34.514931] The buggy address belongs to the object at ffff8801cded2300 [ 34.514931] which belongs to the cache kmalloc-256 of size 256 [ 34.527548] The buggy address is located 40 bytes inside of [ 34.527548] 256-byte region [ffff8801cded2300, ffff8801cded2400) [ 34.539299] The buggy address belongs to the page: [ 34.544189] page:ffffea000737b480 count:1 mapcount:0 mapping:ffff8801cded2080 index:0x0 [ 34.552292] flags: 0x200000000000100(slab) [ 34.556490] raw: 0200000000000100 ffff8801cded2080 0000000000000000 000000010000000c [ 34.564336] raw: ffffea0007388c20 ffffea0007378d20 ffff8801dac007c0 0000000000000000 [ 34.572176] page dumped because: kasan: bad access detected [ 34.577844] [ 34.579435] Memory state around the buggy address: [ 34.584327] ffff8801cded2200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.591648] ffff8801cded2280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 34.598968] >ffff8801cded2300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.606288] ^ [ 34.610918] ffff8801cded2380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 34.618239] ffff8801cded2400: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 34.625557] ================================================================== [ 34.632877] Disabling lock debugging due to kernel taint [ 34.638288] Kernel panic - not syncing: panic_on_warn set ... [ 34.638288] [ 34.645613] CPU: 1 PID: 3322 Comm: syz-executor0 Tainted: G B 4.14.0-rc2-mm1+ #11 [ 34.654321] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.663638] Call Trace: [ 34.666188] dump_stack+0x194/0x257 [ 34.669780] ? arch_local_irq_restore+0x53/0x53 [ 34.674413] ? vprintk_default+0x28/0x30 [ 34.678440] ? __lock_acquire+0x4060/0x4620 [ 34.682727] panic+0x1e4/0x41c [ 34.685884] ? refcount_error_report+0x214/0x214 [ 34.690608] ? __lock_acquire+0x407b/0x4620 [ 34.694893] kasan_end_report+0x50/0x50 [ 34.698829] kasan_report+0x144/0x340 [ 34.702595] __asan_report_load8_noabort+0x14/0x20 [ 34.707486] __lock_acquire+0x407b/0x4620 [ 34.711601] ? unwind_dump+0x4c0/0x4c0 [ 34.715453] ? __unwind_start+0x169/0x330 [ 34.719568] ? __kernel_text_address+0xd/0x40 [ 34.724026] ? unwind_get_return_address+0x61/0xa0 [ 34.728921] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.734073] ? unwind_get_return_address+0x61/0xa0 [ 34.738967] ? __save_stack_trace+0x61/0xd0 [ 34.743252] ? get_signal+0x73f/0x16d0 [ 34.747104] ? save_stack_trace+0x16/0x20 [ 34.751218] ? __lock_acquire+0x20fd/0x4620 [ 34.755507] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.760664] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 34.765818] ? __bpf_address_lookup+0x2b0/0x2b0 [ 34.770453] ? osq_unlock+0x350/0x350 [ 34.774216] ? lock_release+0xd70/0xd70 [ 34.778156] ? __free_insn_slot+0x5c0/0x5c0 [ 34.782444] ? check_noncircular+0x20/0x20 [ 34.786645] ? is_bpf_text_address+0xa4/0x120 [ 34.791105] ? kernel_text_address+0x102/0x140 [ 34.795651] ? __kernel_text_address+0xd/0x40 [ 34.800114] ? find_held_lock+0x39/0x1d0 [ 34.804140] ? lock_downgrade+0x990/0x990 [ 34.808254] ? check_noncircular+0x20/0x20 [ 34.812451] ? kasan_kmalloc+0xad/0xe0 [ 34.816312] lock_acquire+0x1d5/0x580 [ 34.820078] ? exit_pi_state_list+0x369/0x7a0 [ 34.824539] ? lock_release+0xd70/0xd70 [ 34.828475] ? do_raw_spin_trylock+0x190/0x190 [ 34.833034] ? find_held_lock+0x39/0x1d0 [ 34.837065] _raw_spin_lock_irq+0x5e/0x80 [ 34.841177] ? exit_pi_state_list+0x369/0x7a0 [ 34.845636] exit_pi_state_list+0x369/0x7a0 [ 34.849926] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 34.855947] ? lock_release+0xd70/0xd70 [ 34.859897] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 34.866093] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 34.871162] ? __might_sleep+0x95/0x190 [ 34.875101] ? __might_fault+0x188/0x1d0 [ 34.879127] ? do_raw_spin_trylock+0x190/0x190 [ 34.883673] mm_release+0x46d/0x590 [ 34.887264] ? do_raw_spin_trylock+0x190/0x190 [ 34.891808] ? mm_access+0x140/0x140