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-1,10.128.0.60' (ECDSA) to the list of known hosts. 2017/10/01 20:13:01 parsed 1 programs 2017/10/01 20:13:01 executed programs: 0 syzkaller login: [ 38.442395] ================================================================== [ 38.449815] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 38.456459] Read of size 8 at addr ffff8801c62b8ae8 by task syz-executor1/4129 [ 38.463789] [ 38.465389] CPU: 0 PID: 4129 Comm: syz-executor1 Not tainted 4.14.0-rc2-next-20170929+ #32 [ 38.473754] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 38.483083] Call Trace: [ 38.485654] dump_stack+0x194/0x257 [ 38.489263] ? arch_local_irq_restore+0x53/0x53 [ 38.493911] ? show_regs_print_info+0x65/0x65 [ 38.498375] ? __kernel_text_address+0xd/0x40 [ 38.502841] ? __lock_acquire+0x407b/0x4620 [ 38.507132] print_address_description+0x73/0x250 [ 38.511942] ? __lock_acquire+0x407b/0x4620 [ 38.516232] kasan_report+0x25b/0x340 [ 38.520002] __asan_report_load8_noabort+0x14/0x20 [ 38.524905] __lock_acquire+0x407b/0x4620 [ 38.529026] ? unwind_dump+0x4c0/0x4c0 [ 38.532889] ? __unwind_start+0x169/0x330 [ 38.537022] ? __kernel_text_address+0xd/0x40 [ 38.541491] ? unwind_get_return_address+0x61/0xa0 [ 38.546397] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.551573] ? unwind_get_return_address+0x61/0xa0 [ 38.556474] ? __save_stack_trace+0x61/0xd0 [ 38.560773] ? get_signal+0x73f/0x16d0 [ 38.564639] ? save_stack_trace+0x16/0x20 [ 38.568761] ? __lock_acquire+0x20fd/0x4620 [ 38.573064] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.578228] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.583394] ? save_stack_trace+0x16/0x20 [ 38.587519] ? __lock_acquire+0x20fd/0x4620 [ 38.591815] ? osq_unlock+0x350/0x350 [ 38.595584] ? save_stack_trace+0x16/0x20 [ 38.599700] ? lock_release+0xd70/0xd70 [ 38.603646] ? check_noncircular+0x20/0x20 [ 38.607857] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.613032] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 38.618200] ? find_held_lock+0x39/0x1d0 [ 38.622229] ? lock_downgrade+0x990/0x990 [ 38.626348] ? check_noncircular+0x20/0x20 [ 38.630561] lock_acquire+0x1d5/0x580 [ 38.634343] ? exit_pi_state_list+0x369/0x7a0 [ 38.638826] ? lock_release+0xd70/0xd70 [ 38.642776] ? do_raw_spin_trylock+0x190/0x190 [ 38.647327] ? find_held_lock+0x39/0x1d0 [ 38.651359] _raw_spin_lock_irq+0x5e/0x80 [ 38.655479] ? exit_pi_state_list+0x369/0x7a0 [ 38.659947] exit_pi_state_list+0x369/0x7a0 [ 38.664256] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 38.670288] ? lock_release+0xd70/0xd70 [ 38.674235] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 38.680092] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 38.685168] ? __might_sleep+0x95/0x190 [ 38.689111] ? __might_fault+0x188/0x1d0 [ 38.693151] ? do_raw_spin_trylock+0x190/0x190 [ 38.697703] mm_release+0x46d/0x590 [ 38.701295] ? do_raw_spin_trylock+0x190/0x190 [ 38.705845] ? mm_access+0x140/0x140 [ 38.709526] ? _raw_spin_unlock_irq+0x27/0x70 [ 38.713999] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 38.718989] ? trace_hardirqs_on+0xd/0x10 [ 38.723111] ? _raw_spin_unlock_irq+0x27/0x70 [ 38.727587] ? acct_collect+0x637/0x800 [ 38.731537] do_exit+0x481/0x1b00 [ 38.734960] ? mm_update_next_owner+0x930/0x930 [ 38.739597] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 38.745448] ? find_held_lock+0x39/0x1d0 [ 38.749488] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 38.754835] ? check_noncircular+0x20/0x20 [ 38.759049] ? fault_in_user_writeable+0x90/0x90 [ 38.763779] ? futex_wake+0x680/0x680 [ 38.767553] ? find_held_lock+0x39/0x1d0 [ 38.771594] ? lock_downgrade+0x990/0x990 [ 38.775719] ? recalc_sigpending_tsk+0x117/0x150 [ 38.780448] ? recalc_sigpending+0x103/0x160 [ 38.784832] ? recalc_sigpending_tsk+0x150/0x150 [ 38.789562] ? get_signal+0x2b2/0x16d0 [ 38.793419] do_group_exit+0x149/0x400 [ 38.797280] ? __lock_is_held+0xbc/0x140 [ 38.801470] ? SyS_exit+0x30/0x30 [ 38.804906] ? _raw_spin_unlock_irq+0x27/0x70 [ 38.809394] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 38.814388] get_signal+0x73f/0x16d0 [ 38.818105] ? ptrace_notify+0x130/0x130 [ 38.822138] ? is_bpf_text_address+0xa4/0x120 [ 38.826602] ? kernel_text_address+0x102/0x140 [ 38.831152] ? exit_robust_list+0x240/0x240 [ 38.835441] ? __save_stack_trace+0x7e/0xd0 [ 38.839731] ? depot_save_stack+0x12c/0x490 [ 38.844029] do_signal+0x94/0x1ee0 [ 38.847543] ? save_stack+0xa3/0xd0 [ 38.851147] ? find_held_lock+0x39/0x1d0 [ 38.855182] ? setup_sigcontext+0x7d0/0x7d0 [ 38.859476] ? lock_downgrade+0x990/0x990 [ 38.863602] ? lock_release+0xd70/0xd70 [ 38.867549] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 38.873407] ? exit_to_usermode_loop+0x8c/0x310 [ 38.878050] exit_to_usermode_loop+0x214/0x310 [ 38.882614] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 38.888128] ? kasan_check_write+0x14/0x20 [ 38.892344] syscall_return_slowpath+0x42f/0x510 [ 38.897082] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 38.902083] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 38.906995] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 38.911987] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 38.916717] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 38.921439] RIP: 0033:0x4520a9 [ 38.924596] RSP: 002b:00007fb06a42ccf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 38.932279] RAX: fffffffffffffe00 RBX: 0000000000718238 RCX: 00000000004520a9 [ 38.939535] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718238 [ 38.946809] RBP: 0000000000718210 R08: 0000000000000000 R09: 0000000000000000 [ 38.954065] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 38.961314] R13: 00007ffce4250bff R14: 00007fb06a42d9c0 R15: 000000000000000a [ 38.968572] [ 38.970178] Allocated by task 4147: [ 38.973803] save_stack_trace+0x16/0x20 [ 38.977756] save_stack+0x43/0xd0 [ 38.981187] kasan_kmalloc+0xad/0xe0 [ 38.984877] kmem_cache_alloc_trace+0x136/0x750 [ 38.989516] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 38.994593] futex_requeue+0x1887/0x2370 [ 38.998633] do_futex+0x7f5/0x20d0 [ 39.002153] SyS_futex+0x260/0x390 [ 39.005665] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 39.010389] [ 39.011983] Freed by task 4118: [ 39.015237] save_stack_trace+0x16/0x20 [ 39.019187] save_stack+0x43/0xd0 [ 39.022615] kasan_slab_free+0x71/0xc0 [ 39.026486] kfree+0xca/0x250 [ 39.029568] put_pi_state+0x3f4/0x560 [ 39.033337] unqueue_me_pi+0x4a/0xc0 [ 39.037024] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 39.042800] do_futex+0x825/0x20d0 [ 39.046318] SyS_futex+0x260/0x390 [ 39.049832] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 39.054556] [ 39.056162] The buggy address belongs to the object at ffff8801c62b8ac0 [ 39.056162] which belongs to the cache kmalloc-256 of size 256 [ 39.068791] The buggy address is located 40 bytes inside of [ 39.068791] 256-byte region [ffff8801c62b8ac0, ffff8801c62b8bc0) [ 39.080554] The buggy address belongs to the page: [ 39.085461] page:ffffea000718ae00 count:1 mapcount:0 mapping:ffff8801c62b80c0 index:0x0 [ 39.093582] flags: 0x200000000000100(slab) [ 39.097803] raw: 0200000000000100 ffff8801c62b80c0 0000000000000000 000000010000000c [ 39.105658] raw: ffffea000717cfe0 ffffea000716e020 ffff8801dac007c0 0000000000000000 [ 39.113506] page dumped because: kasan: bad access detected [ 39.119188] [ 39.120798] Memory state around the buggy address: [ 39.125702] ffff8801c62b8980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 39.133032] ffff8801c62b8a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 39.140363] >ffff8801c62b8a80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 39.147683] ^ [ 39.154397] ffff8801c62b8b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 39.161718] ffff8801c62b8b80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 39.169044] ================================================================== [ 39.176371] Disabling lock debugging due to kernel taint [ 39.181784] Kernel panic - not syncing: panic_on_warn set ... [ 39.181784] [ 39.189111] CPU: 0 PID: 4129 Comm: syz-executor1 Tainted: G B 4.14.0-rc2-next-20170929+ #32 [ 39.198690] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 39.208008] Call Trace: [ 39.210567] dump_stack+0x194/0x257 [ 39.214160] ? arch_local_irq_restore+0x53/0x53 [ 39.218796] ? vprintk_default+0x28/0x30 [ 39.222827] ? __lock_acquire+0x4000/0x4620 [ 39.227115] panic+0x1e4/0x41c [ 39.230273] ? refcount_error_report+0x214/0x214 [ 39.234995] ? __lock_acquire+0x407b/0x4620 [ 39.239285] kasan_end_report+0x50/0x50 [ 39.243222] kasan_report+0x144/0x340 [ 39.246989] __asan_report_load8_noabort+0x14/0x20 [ 39.251883] __lock_acquire+0x407b/0x4620 [ 39.255995] ? unwind_dump+0x4c0/0x4c0 [ 39.259848] ? __unwind_start+0x169/0x330 [ 39.263960] ? __kernel_text_address+0xd/0x40 [ 39.268418] ? unwind_get_return_address+0x61/0xa0 [ 39.273315] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 39.278468] ? unwind_get_return_address+0x61/0xa0 [ 39.283360] ? __save_stack_trace+0x61/0xd0 [ 39.287649] ? get_signal+0x73f/0x16d0 [ 39.291501] ? save_stack_trace+0x16/0x20 [ 39.295612] ? __lock_acquire+0x20fd/0x4620 [ 39.299899] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 39.305058] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 39.310212] ? save_stack_trace+0x16/0x20 [ 39.314322] ? __lock_acquire+0x20fd/0x4620 [ 39.318606] ? osq_unlock+0x350/0x350 [ 39.322370] ? save_stack_trace+0x16/0x20 [ 39.326482] ? lock_release+0xd70/0xd70 [ 39.330424] ? check_noncircular+0x20/0x20 [ 39.334625] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 39.339781] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 39.344937] ? find_held_lock+0x39/0x1d0 [ 39.348967] ? lock_downgrade+0x990/0x990 [ 39.353079] ? check_noncircular+0x20/0x20 [ 39.357277] lock_acquire+0x1d5/0x580 [ 39.361047] ? exit_pi_state_list+0x369/0x7a0 [ 39.365511] ? lock_release+0xd70/0xd70 [ 39.369450] ? do_raw_spin_trylock+0x190/0x190 [ 39.373995] ? find_held_lock+0x39/0x1d0 [ 39.378032] _raw_spin_lock_irq+0x5e/0x80 [ 39.382145] ? exit_pi_state_list+0x369/0x7a0 [ 39.386606] exit_pi_state_list+0x369/0x7a0 [ 39.390905] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 39.396929] ? lock_release+0xd70/0xd70 [ 39.400871] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 39.406721] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 39.411795] ? __might_sleep+0x95/0x190 [ 39.415739] ? __might_fault+0x188/0x1d0 [ 39.419766] ? do_raw_spin_trylock+0x190/0x190 [ 39.424314] mm_release+0x46d/0x590 [ 39.427905] ? do_raw_spin_trylock+0x190/0x190 [ 39.432457] ? mm_access+0x140/0x140 [ 39.436136] ? _raw_spin_unlock_irq+0x27/0x70 [ 39.440597] ? trace_hardirqs_on_caller+0x421/0x5c0