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-386-4,10.128.0.54' (ECDSA) to the list of known hosts. 2017/11/01 19:19:09 parsed 1 programs 2017/11/01 19:19:09 executed programs: 0 2017/11/01 19:19:14 executed programs: 461 2017/11/01 19:19:19 executed programs: 920 syzkaller login: [ 858.590590] ================================================================== [ 858.591784] BUG: KASAN: use-after-free in __lock_acquire+0x3c9f/0x3d50 [ 858.592679] Read of size 8 at addr ffff8801d17fc3e8 by task syz-executor0/9222 [ 858.593658] [ 858.593893] CPU: 1 PID: 9222 Comm: syz-executor0 Not tainted 4.14.0-rc7+ #67 [ 858.594833] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 858.596052] Call Trace: [ 858.596408] dump_stack+0x194/0x257 [ 858.596896] ? arch_local_irq_restore+0x53/0x53 [ 858.597516] ? show_regs_print_info+0x65/0x65 [ 858.598113] ? print_irqtrace_events+0x270/0x270 [ 858.598798] ? print_irqtrace_events+0x270/0x270 [ 858.599429] ? __lock_acquire+0x3c9f/0x3d50 [ 858.600005] print_address_description+0x73/0x250 [ 858.600665] ? __lock_acquire+0x3c9f/0x3d50 [ 858.601245] kasan_report+0x25b/0x340 [ 858.601755] __asan_report_load8_noabort+0x14/0x20 [ 858.602411] __lock_acquire+0x3c9f/0x3d50 [ 858.602966] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 858.603656] ? exit_pi_state_list+0x369/0x7a0 [ 858.604254] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 858.604941] ? __lock_acquire+0x6aa/0x3d50 [ 858.605517] ? __lock_acquire+0x6aa/0x3d50 [ 858.606084] ? print_irqtrace_events+0x270/0x270 [ 858.606717] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 858.607407] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 858.608095] ? osq_unlock+0x350/0x350 [ 858.608604] ? __lock_acquire+0x6aa/0x3d50 [ 858.609171] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 858.609871] ? mark_held_locks+0xaf/0x100 [ 858.610971] ? retint_kernel+0x10/0x10 [ 858.614823] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 858.619807] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 858.624529] ? retint_kernel+0x10/0x10 [ 858.628386] lock_acquire+0x1d5/0x580 [ 858.632152] ? lock_acquire+0x1d5/0x580 [ 858.636094] ? exit_pi_state_list+0x369/0x7a0 [ 858.640557] ? lock_downgrade+0x990/0x990 [ 858.644670] ? check_noncircular+0x20/0x20 [ 858.648873] ? lock_release+0xa40/0xa40 [ 858.652811] ? do_raw_spin_trylock+0x190/0x190 [ 858.657359] ? _raw_spin_unlock_irq+0x27/0x70 [ 858.661820] _raw_spin_lock_irq+0x5e/0x80 [ 858.665931] ? exit_pi_state_list+0x369/0x7a0 [ 858.670404] exit_pi_state_list+0x369/0x7a0 [ 858.674692] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 858.680718] ? lock_release+0xa40/0xa40 [ 858.684658] ? check_same_owner+0x320/0x320 [ 858.688944] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 858.694012] ? __might_sleep+0x95/0x190 [ 858.697954] ? __might_fault+0x188/0x1d0 [ 858.701988] ? do_raw_spin_trylock+0x190/0x190 [ 858.706536] mm_release+0x46d/0x590 [ 858.710126] ? do_raw_spin_trylock+0x190/0x190 [ 858.714684] ? mm_access+0x140/0x140 [ 858.718366] ? _raw_spin_unlock_irq+0x27/0x70 [ 858.722830] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 858.727813] ? trace_hardirqs_on+0xd/0x10 [ 858.731926] ? _raw_spin_unlock_irq+0x27/0x70 [ 858.736389] ? acct_collect+0x637/0x800 [ 858.740331] do_exit+0x481/0x1ad0 [ 858.743751] ? __might_sleep+0x95/0x190 [ 858.747690] ? mm_update_next_owner+0x930/0x930 [ 858.752321] ? find_held_lock+0x35/0x1d0 [ 858.756348] ? futex_wait+0x402/0x990 [ 858.760113] ? lock_downgrade+0x990/0x990 [ 858.764228] ? do_raw_spin_trylock+0x190/0x190 [ 858.768778] ? fault_in_user_writeable+0x90/0x90 [ 858.773499] ? futex_wake+0x680/0x680 [ 858.777266] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 858.782334] ? futex_wait+0x69e/0x990 [ 858.786100] ? check_noncircular+0x20/0x20 [ 858.790303] ? futex_wait_setup+0x3d0/0x3d0 [ 858.794594] ? __hrtimer_init+0x140/0x140 [ 858.798710] ? nohz_balance_exit_idle.part.85+0x70/0x70 [ 858.804049] ? hash_futex+0x15/0x210 [ 858.807730] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 858.812799] ? futex_wake+0x2ca/0x680 [ 858.816564] ? find_held_lock+0x35/0x1d0 [ 858.820593] ? get_signal+0x7ae/0x16d0 [ 858.824448] ? lock_downgrade+0x990/0x990 [ 858.828563] do_group_exit+0x149/0x400 [ 858.832416] ? __lock_is_held+0xb6/0x140 [ 858.836445] ? SyS_exit+0x30/0x30 [ 858.839861] ? _raw_spin_unlock_irq+0x27/0x70 [ 858.844322] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 858.849303] get_signal+0x73f/0x16d0 [ 858.852982] ? ptrace_notify+0x130/0x130 [ 858.857007] ? __schedule+0x8f3/0x2060 [ 858.860862] ? __sched_text_start+0x8/0x8 [ 858.864978] ? userfaultfd_unmap_complete+0x327/0x510 [ 858.870139] do_signal+0x94/0x1ee0 [ 858.873646] ? do_mmap+0x34f/0xd40 [ 858.877153] ? up_write+0x6b/0x120 [ 858.880659] ? setup_sigcontext+0x7d0/0x7d0 [ 858.884948] ? security_mmap_file+0x143/0x180 [ 858.889408] ? schedule+0xf5/0x430 [ 858.892914] ? vm_mmap_pgoff+0x13b/0x280 [ 858.896941] ? __schedule+0x2060/0x2060 [ 858.900879] ? vma_is_stack_for_current+0xa0/0xa0 [ 858.905688] ? __compat_get_timespec+0xd9/0x120 [ 858.910326] ? exit_to_usermode_loop+0x8c/0x310 [ 858.914959] exit_to_usermode_loop+0x214/0x310 [ 858.919505] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 858.925004] ? do_fast_syscall_32+0x158/0xf05 [ 858.929463] do_fast_syscall_32+0x83e/0xf05 [ 858.933749] ? compat_start_thread+0x80/0x80 [ 858.938121] ? do_int80_syscall_32+0x940/0x940 [ 858.942667] ? syscall_return_slowpath+0x2b3/0x510 [ 858.947558] ? finish_task_switch+0x1aa/0x740 [ 858.952017] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 858.956997] ? sysret32_from_system_call+0x5/0x3b [ 858.961823] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 858.966632] entry_SYSENTER_compat+0x51/0x60 [ 858.971003] RIP: 0023:0xf7f5ec79 [ 858.974333] RSP: 002b:00000000f7f5a10c EFLAGS: 00000296 ORIG_RAX: 00000000000000f0 [ 858.982004] RAX: fffffffffffffe00 RBX: 000000000816803c RCX: 0000000000000000 [ 858.989243] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 858.996476] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 859.003721] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 859.010956] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 859.018196] [ 859.019790] Allocated by task 9251: [ 859.023385] save_stack_trace+0x16/0x20 [ 859.027326] save_stack+0x43/0xd0 [ 859.030743] kasan_kmalloc+0xad/0xe0 [ 859.034421] kmem_cache_alloc_trace+0x136/0x750 [ 859.039053] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 859.044117] futex_requeue+0x1887/0x2370 [ 859.048138] do_futex+0x7f5/0x20d0 [ 859.051641] compat_SyS_futex+0x27f/0x380 [ 859.055750] do_fast_syscall_32+0x3f2/0xf05 [ 859.060035] entry_SYSENTER_compat+0x51/0x60 [ 859.064403] [ 859.065993] Freed by task 9243: [ 859.069238] save_stack_trace+0x16/0x20 [ 859.073176] save_stack+0x43/0xd0 [ 859.076591] kasan_slab_free+0x71/0xc0 [ 859.080442] kfree+0xca/0x250 [ 859.083511] do_exit+0x1502/0x1ad0 [ 859.087013] do_group_exit+0x149/0x400 [ 859.090864] get_signal+0x73f/0x16d0 [ 859.094544] do_signal+0x94/0x1ee0 [ 859.098048] exit_to_usermode_loop+0x214/0x310 [ 859.102593] do_fast_syscall_32+0x83e/0xf05 [ 859.106881] entry_SYSENTER_compat+0x51/0x60 [ 859.111252] [ 859.112845] The buggy address belongs to the object at ffff8801d17fc3c0 [ 859.112845] which belongs to the cache kmalloc-256 of size 256 [ 859.125464] The buggy address is located 40 bytes inside of [ 859.125464] 256-byte region [ffff8801d17fc3c0, ffff8801d17fc4c0) [ 859.137214] The buggy address belongs to the page: [ 859.142108] page:ffffea000745ff00 count:1 mapcount:0 mapping:ffff8801d17fc000 index:0x0 [ 859.150214] flags: 0x200000000000100(slab) [ 859.154415] raw: 0200000000000100 ffff8801d17fc000 0000000000000000 000000010000000c [ 859.162258] raw: ffffea000745fd20 ffffea0007433ce0 ffff8801dac007c0 0000000000000000 [ 859.170099] page dumped because: kasan: bad access detected [ 859.175771] [ 859.177362] Memory state around the buggy address: [ 859.182254] ffff8801d17fc280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 859.189574] ffff8801d17fc300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 859.196897] >ffff8801d17fc380: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 859.204221] ^ [ 859.210938] ffff8801d17fc400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 859.218258] ffff8801d17fc480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 859.225578] ================================================================== [ 859.232900] Disabling lock debugging due to kernel taint [ 859.238314] Kernel panic - not syncing: panic_on_warn set ... [ 859.238314] [ 859.245643] CPU: 1 PID: 9222 Comm: syz-executor0 Tainted: G B 4.14.0-rc7+ #67 [ 859.254006] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 859.263325] Call Trace: [ 859.265879] dump_stack+0x194/0x257 [ 859.269469] ? arch_local_irq_restore+0x53/0x53 [ 859.274103] ? kasan_end_report+0x32/0x50 [ 859.278213] ? lock_downgrade+0x990/0x990 [ 859.282327] ? __lock_acquire+0x3c90/0x3d50 [ 859.286614] panic+0x1e4/0x417 [ 859.289769] ? __warn+0x1d9/0x1d9 [ 859.293188] ? __lock_acquire+0x3c9f/0x3d50 [ 859.297471] kasan_end_report+0x50/0x50 [ 859.301409] kasan_report+0x144/0x340 [ 859.305176] __asan_report_load8_noabort+0x14/0x20 [ 859.310076] __lock_acquire+0x3c9f/0x3d50 [ 859.314188] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 859.319340] ? exit_pi_state_list+0x369/0x7a0 [ 859.323800] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 859.328955] ? __lock_acquire+0x6aa/0x3d50 [ 859.333154] ? __lock_acquire+0x6aa/0x3d50 [ 859.337353] ? print_irqtrace_events+0x270/0x270 [ 859.342072] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 859.347231] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 859.352385] ? osq_unlock+0x350/0x350 [ 859.356150] ? __lock_acquire+0x6aa/0x3d50 [ 859.360350] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 859.365506] ? mark_held_locks+0xaf/0x100 [ 859.369617] ? retint_kernel+0x10/0x10 [ 859.373470] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 859.378456] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 859.383179] ? retint_kernel+0x10/0x10 [ 859.387032] lock_acquire+0x1d5/0x580 [ 859.390795] ? lock_acquire+0x1d5/0x580 [ 859.394731] ? exit_pi_state_list+0x369/0x7a0 [ 859.399190] ? lock_downgrade+0x990/0x990 [ 859.403302] ? check_noncircular+0x20/0x20 [ 859.407500] ? lock_release+0xa40/0xa40 [ 859.411438] ? do_raw_spin_trylock+0x190/0x190 [ 859.415984] ? _raw_spin_unlock_irq+0x27/0x70 [ 859.420442] _raw_spin_lock_irq+0x5e/0x80 [ 859.424560] ? exit_pi_state_list+0x369/0x7a0 [ 859.429017] exit_pi_state_list+0x369/0x7a0 [ 859.433305] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 859.439326] ? lock_release+0xa40/0xa40 [ 859.443263] ? check_same_owner+0x320/0x320 [ 859.447548] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 859.452616] ? __might_sleep+0x95/0x190 [ 859.456558] ? __might_fault+0x188/0x1d0 [ 859.460582] ? do_raw_spin_trylock+0x190/0x190 [ 859.465128] mm_release+0x46d/0x590 [ 859.468719] ? do_raw_spin_trylock+0x190/0x190 [ 859.473265] ? mm_access+0x140/0x140 [ 859.476941] ? _raw_spin_unlock_irq+0x27/0x70 [ 859.481400] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 859.486379] ? trace_hardirqs_on+0xd/0x10 [ 859.490492] ? _raw_spin_unlock_irq+0x27/0x70 [ 859.494948] ? acct_collect+0x637/0x800 [ 859.498887] do_exit+0x481/0x1ad0 [ 859.502305] ? __might_sleep+0x95/0x190 [ 859.506243] ? mm_update_next_owner+0x930/0x930 [ 859.510875] ? find_held_lock+0x35/0x1d0 [ 859.514900] ? futex_wait+0x402/0x990 [ 859.518664] ? lock_downgrade+0x990/0x990 [ 859.522776] ? do_raw_spin_trylock+0x190/0x190 [ 859.527322] ? fault_in_user_writeable+0x90/0x90 [ 859.532042] ? futex_wake+0x680/0x680 [ 859.535807] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 859.540883] ? futex_wait+0x69e/0x990 [ 859.544650] ? check_noncircular+0x20/0x20 [ 859.548849] ? futex_wait_setup+0x3d0/0x3d0 [ 859.553137] ? __hrtimer_init+0x140/0x140 [ 859.557250] ? nohz_balance_exit_idle.part.85+0x70/0x70 [ 859.562576] ? hash_futex+0x15/0x210 [ 859.566255] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 859.571324] ? futex_wake+0x2ca/0x680 [ 859.575088] ? find_held_lock+0x35/0x1d0 [ 859.579114] ? get_signal+0x7ae/0x16d0 [ 859.582964] ? lock_downgrade+0x990/0x990 [ 859.587076] do_group_exit+0x149/0x400 [ 859.590928] ? __lock_is_held+0xb6/0x140