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-7,10.128.0.34' (ECDSA) to the list of known hosts. 2017/10/01 23:23:52 parsed 1 programs 2017/10/01 23:23:52 executed programs: 0 syzkaller login: [ 32.523427] ================================================================== [ 32.530800] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 32.537428] Read of size 8 at addr ffff8801ce2d91e8 by task syz-executor0/3051 [ 32.544745] [ 32.546337] CPU: 1 PID: 3051 Comm: syz-executor0 Not tainted 4.14.0-rc2+ #111 [ 32.553569] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.562883] Call Trace: [ 32.565437] dump_stack+0x194/0x257 [ 32.569027] ? arch_local_irq_restore+0x53/0x53 [ 32.573657] ? show_regs_print_info+0x65/0x65 [ 32.578116] ? __kernel_text_address+0xd/0x40 [ 32.582573] ? __lock_acquire+0x407b/0x4620 [ 32.586857] print_address_description+0x73/0x250 [ 32.591661] ? __lock_acquire+0x407b/0x4620 [ 32.595943] kasan_report+0x25b/0x340 [ 32.599710] __asan_report_load8_noabort+0x14/0x20 [ 32.604600] __lock_acquire+0x407b/0x4620 [ 32.608721] ? unwind_dump+0x4c0/0x4c0 [ 32.612569] ? __unwind_start+0x169/0x330 [ 32.616680] ? __kernel_text_address+0xd/0x40 [ 32.621138] ? unwind_get_return_address+0x61/0xa0 [ 32.626034] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.631184] ? unwind_get_return_address+0x61/0xa0 [ 32.636074] ? __save_stack_trace+0x61/0xd0 [ 32.640359] ? get_signal+0x73f/0x16d0 [ 32.644209] ? save_stack_trace+0x16/0x20 [ 32.648318] ? __lock_acquire+0x20fd/0x4620 [ 32.652604] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.657759] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.662911] ? save_stack_trace+0x16/0x20 [ 32.667019] ? __lock_acquire+0x20fd/0x4620 [ 32.671303] ? osq_unlock+0x350/0x350 [ 32.675066] ? save_stack_trace+0x16/0x20 [ 32.679182] ? check_noncircular+0x20/0x20 [ 32.683384] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.688538] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.693689] ? find_held_lock+0x39/0x1d0 [ 32.697715] ? find_held_lock+0x39/0x1d0 [ 32.701741] ? lock_downgrade+0x990/0x990 [ 32.705850] ? check_noncircular+0x20/0x20 [ 32.710048] lock_acquire+0x1d5/0x580 [ 32.713815] ? exit_pi_state_list+0x369/0x7a0 [ 32.718277] ? lock_release+0xd70/0xd70 [ 32.722213] ? do_raw_spin_trylock+0x190/0x190 [ 32.726755] ? find_held_lock+0x39/0x1d0 [ 32.730782] _raw_spin_lock_irq+0x5e/0x80 [ 32.734891] ? exit_pi_state_list+0x369/0x7a0 [ 32.739347] exit_pi_state_list+0x369/0x7a0 [ 32.743632] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 32.749650] ? lock_release+0xd70/0xd70 [ 32.753588] ? check_same_owner+0x320/0x320 [ 32.757871] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 32.762937] ? __might_sleep+0x95/0x190 [ 32.766874] ? __might_fault+0x188/0x1d0 [ 32.770898] ? do_raw_spin_trylock+0x190/0x190 [ 32.775443] mm_release+0x46d/0x590 [ 32.779033] ? do_raw_spin_trylock+0x190/0x190 [ 32.783578] ? mm_access+0x140/0x140 [ 32.787253] ? _raw_spin_unlock_irq+0x27/0x70 [ 32.791709] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.796693] ? trace_hardirqs_on+0xd/0x10 [ 32.800802] ? _raw_spin_unlock_irq+0x27/0x70 [ 32.805257] ? acct_collect+0x637/0x800 [ 32.809195] do_exit+0x481/0x1af0 [ 32.812612] ? mm_update_next_owner+0x930/0x930 [ 32.817242] ? check_same_owner+0x320/0x320 [ 32.821526] ? futex_wait_setup+0x14a/0x3d0 [ 32.825810] ? __might_sleep+0x95/0x190 [ 32.829746] ? osq_unlock+0x350/0x350 [ 32.833507] ? futex_wait_queue_me+0x524/0x7e0 [ 32.838054] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 32.843381] ? memset+0x31/0x40 [ 32.846625] ? check_noncircular+0x20/0x20 [ 32.850823] ? futex_wait_setup+0x22e/0x3d0 [ 32.855106] ? futex_wake+0x680/0x680 [ 32.858872] ? find_held_lock+0x39/0x1d0 [ 32.862905] ? lock_downgrade+0x990/0x990 [ 32.867017] ? recalc_sigpending_tsk+0x117/0x150 [ 32.871735] ? recalc_sigpending+0x103/0x160 [ 32.876106] ? recalc_sigpending_tsk+0x150/0x150 [ 32.880821] ? get_signal+0x2b2/0x16d0 [ 32.884672] do_group_exit+0x149/0x400 [ 32.888523] ? __lock_is_held+0xbc/0x140 [ 32.892545] ? SyS_exit+0x30/0x30 [ 32.895970] ? _raw_spin_unlock_irq+0x27/0x70 [ 32.900428] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.905404] get_signal+0x73f/0x16d0 [ 32.909080] ? ptrace_notify+0x130/0x130 [ 32.913106] ? exit_robust_list+0x240/0x240 [ 32.917401] ? check_noncircular+0x20/0x20 [ 32.921603] do_signal+0x94/0x1ee0 [ 32.925108] ? find_held_lock+0x39/0x1d0 [ 32.929133] ? setup_sigcontext+0x7d0/0x7d0 [ 32.933420] ? lock_downgrade+0x990/0x990 [ 32.937532] ? lock_release+0xd70/0xd70 [ 32.941467] ? check_same_owner+0x320/0x320 [ 32.945749] ? lock_acquire+0x1d5/0x580 [ 32.949683] ? finish_task_switch+0x1aa/0x740 [ 32.954142] ? exit_to_usermode_loop+0x8c/0x310 [ 32.958772] exit_to_usermode_loop+0x214/0x310 [ 32.963318] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 32.968817] ? kasan_check_write+0x14/0x20 [ 32.973017] syscall_return_slowpath+0x42f/0x510 [ 32.977734] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 32.982715] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 32.987605] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.992581] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 32.997300] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 33.002017] RIP: 0033:0x4520a9 [ 33.005168] RSP: 002b:00007f0a39912cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 33.012836] RAX: 0000000000000000 RBX: 0000000000718188 RCX: 00000000004520a9 [ 33.020070] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718188 [ 33.027303] RBP: 0000000000718160 R08: 0000000000000000 R09: 0000000000000000 [ 33.034534] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 33.041767] R13: 00007ffc74bfee2f R14: 00007f0a399139c0 R15: 0000000000000003 [ 33.049002] [ 33.050593] Allocated by task 3053: [ 33.054182] save_stack_trace+0x16/0x20 [ 33.058117] save_stack+0x43/0xd0 [ 33.061530] kasan_kmalloc+0xad/0xe0 [ 33.065204] kmem_cache_alloc_trace+0x136/0x750 [ 33.069833] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 33.074896] futex_requeue+0x1887/0x2370 [ 33.078916] do_futex+0x7f5/0x20d0 [ 33.082416] SyS_futex+0x260/0x390 [ 33.086362] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 33.091079] [ 33.092671] Freed by task 3050: [ 33.095913] save_stack_trace+0x16/0x20 [ 33.099850] save_stack+0x43/0xd0 [ 33.103299] kasan_slab_free+0x71/0xc0 [ 33.107151] kfree+0xca/0x250 [ 33.110218] put_pi_state+0x3f4/0x560 [ 33.113979] unqueue_me_pi+0x4a/0xc0 [ 33.117653] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 33.123413] do_futex+0x825/0x20d0 [ 33.126913] SyS_futex+0x260/0x390 [ 33.130414] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 33.135129] [ 33.136719] The buggy address belongs to the object at ffff8801ce2d91c0 [ 33.136719] which belongs to the cache kmalloc-256 of size 256 [ 33.149334] The buggy address is located 40 bytes inside of [ 33.149334] 256-byte region [ffff8801ce2d91c0, ffff8801ce2d92c0) [ 33.161080] The buggy address belongs to the page: [ 33.165971] page:ffffea000738b640 count:1 mapcount:0 mapping:ffff8801ce2d9080 index:0x0 [ 33.174072] flags: 0x200000000000100(slab) [ 33.178271] raw: 0200000000000100 ffff8801ce2d9080 0000000000000000 000000010000000c [ 33.186111] raw: ffffea000738ab20 ffffea000738ae60 ffff8801dac007c0 0000000000000000 [ 33.193952] page dumped because: kasan: bad access detected [ 33.199619] [ 33.201209] Memory state around the buggy address: [ 33.206097] ffff8801ce2d9080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.213414] ffff8801ce2d9100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.220733] >ffff8801ce2d9180: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 33.228050] ^ [ 33.234761] ffff8801ce2d9200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 33.242080] ffff8801ce2d9280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 33.249396] ================================================================== [ 33.256713] Disabling lock debugging due to kernel taint [ 33.262124] Kernel panic - not syncing: panic_on_warn set ... [ 33.262124] [ 33.269445] CPU: 1 PID: 3051 Comm: syz-executor0 Tainted: G B 4.14.0-rc2+ #111 [ 33.277891] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.287217] Call Trace: [ 33.289773] dump_stack+0x194/0x257 [ 33.293362] ? arch_local_irq_restore+0x53/0x53 [ 33.297995] ? vprintk_default+0x28/0x30 [ 33.302020] ? __lock_acquire+0x3ff0/0x4620 [ 33.306307] panic+0x1e4/0x417 [ 33.309462] ? __warn+0x1d9/0x1d9 [ 33.312879] ? __lock_acquire+0x407b/0x4620 [ 33.317164] kasan_end_report+0x50/0x50 [ 33.321103] kasan_report+0x144/0x340 [ 33.324865] __asan_report_load8_noabort+0x14/0x20 [ 33.329754] __lock_acquire+0x407b/0x4620 [ 33.333864] ? unwind_dump+0x4c0/0x4c0 [ 33.337710] ? __unwind_start+0x169/0x330 [ 33.341820] ? __kernel_text_address+0xd/0x40 [ 33.346276] ? unwind_get_return_address+0x61/0xa0 [ 33.351168] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.356318] ? unwind_get_return_address+0x61/0xa0 [ 33.361208] ? __save_stack_trace+0x61/0xd0 [ 33.365491] ? get_signal+0x73f/0x16d0 [ 33.369342] ? save_stack_trace+0x16/0x20 [ 33.373452] ? __lock_acquire+0x20fd/0x4620 [ 33.377736] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.382889] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.388039] ? save_stack_trace+0x16/0x20 [ 33.392148] ? __lock_acquire+0x20fd/0x4620 [ 33.396429] ? osq_unlock+0x350/0x350 [ 33.400189] ? save_stack_trace+0x16/0x20 [ 33.404300] ? check_noncircular+0x20/0x20 [ 33.408497] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.413649] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.418798] ? find_held_lock+0x39/0x1d0 [ 33.422825] ? find_held_lock+0x39/0x1d0 [ 33.426851] ? lock_downgrade+0x990/0x990 [ 33.430962] ? check_noncircular+0x20/0x20 [ 33.435158] lock_acquire+0x1d5/0x580 [ 33.438924] ? exit_pi_state_list+0x369/0x7a0 [ 33.443383] ? lock_release+0xd70/0xd70 [ 33.447317] ? do_raw_spin_trylock+0x190/0x190 [ 33.451860] ? find_held_lock+0x39/0x1d0 [ 33.455887] _raw_spin_lock_irq+0x5e/0x80 [ 33.459996] ? exit_pi_state_list+0x369/0x7a0 [ 33.464451] exit_pi_state_list+0x369/0x7a0 [ 33.468736] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 33.474758] ? lock_release+0xd70/0xd70 [ 33.478693] ? check_same_owner+0x320/0x320 [ 33.482978] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 33.488047] ? __might_sleep+0x95/0x190 [ 33.491990] ? __might_fault+0x188/0x1d0 [ 33.496015] ? do_raw_spin_trylock+0x190/0x190 [ 33.500561] mm_release+0x46d/0x590 [ 33.504150] ? do_raw_spin_trylock+0x190/0x190 [ 33.508694] ? mm_access+0x140/0x140 [ 33.512370] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.516831] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 33.521808] ? trace_hardirqs_on+0xd/0x10