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-386-3,10.128.0.52' (ECDSA) to the list of known hosts. 2017/10/04 06:20:16 parsed 1 programs 2017/10/04 06:20:16 executed programs: 0 2017/10/04 06:20:21 executed programs: 293 2017/10/04 06:20:26 executed programs: 596 syzkaller login: [ 53.038300] ================================================================== [ 53.046012] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 53.052650] Read of size 8 at addr ffff8801c4b40668 by task syz-executor5/6856 [ 53.059970] [ 53.061574] CPU: 0 PID: 6856 Comm: syz-executor5 Not tainted 4.14.0-rc3+ #24 [ 53.068745] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.078075] Call Trace: [ 53.080628] dump_stack+0x194/0x257 [ 53.084219] ? arch_local_irq_restore+0x53/0x53 [ 53.088862] ? show_regs_print_info+0x65/0x65 [ 53.093336] ? __kernel_text_address+0xd/0x40 [ 53.097801] ? __lock_acquire+0x407b/0x4620 [ 53.102089] print_address_description+0x73/0x250 [ 53.106896] ? __lock_acquire+0x407b/0x4620 [ 53.111185] kasan_report+0x25b/0x340 [ 53.114969] __asan_report_load8_noabort+0x14/0x20 [ 53.119885] __lock_acquire+0x407b/0x4620 [ 53.124000] ? unwind_dump+0x4c0/0x4c0 [ 53.127857] ? __kernel_text_address+0xd/0x40 [ 53.132322] ? unwind_get_return_address+0x61/0xa0 [ 53.137230] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 53.142384] ? __save_stack_trace+0x61/0xd0 [ 53.146674] ? get_signal+0x73f/0x16d0 [ 53.150526] ? save_stack_trace+0x16/0x20 [ 53.154644] ? __lock_acquire+0x20fd/0x4620 [ 53.158936] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 53.164094] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 53.169251] ? save_stack_trace+0x16/0x20 [ 53.173361] ? __lock_acquire+0x20fd/0x4620 [ 53.177646] ? osq_unlock+0x350/0x350 [ 53.181417] ? save_stack_trace+0x16/0x20 [ 53.185531] ? check_noncircular+0x20/0x20 [ 53.189734] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 53.194887] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 53.200042] ? __unwind_start+0x169/0x330 [ 53.204152] ? find_held_lock+0x39/0x1d0 [ 53.208186] ? lock_downgrade+0x990/0x990 [ 53.212304] ? check_noncircular+0x20/0x20 [ 53.216502] lock_acquire+0x1d5/0x580 [ 53.220268] ? exit_pi_state_list+0x369/0x7a0 [ 53.224726] ? lock_release+0xd70/0xd70 [ 53.228663] ? do_raw_spin_trylock+0x190/0x190 [ 53.233206] ? find_held_lock+0x39/0x1d0 [ 53.237238] _raw_spin_lock_irq+0x5e/0x80 [ 53.241348] ? exit_pi_state_list+0x369/0x7a0 [ 53.245807] exit_pi_state_list+0x369/0x7a0 [ 53.250094] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 53.256116] ? lock_release+0xd70/0xd70 [ 53.260055] ? check_same_owner+0x320/0x320 [ 53.264339] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 53.269408] ? __might_sleep+0x95/0x190 [ 53.273350] ? __might_fault+0x188/0x1d0 [ 53.277377] ? do_raw_spin_trylock+0x190/0x190 [ 53.281924] mm_release+0x46d/0x590 [ 53.285513] ? do_raw_spin_trylock+0x190/0x190 [ 53.290058] ? mm_access+0x140/0x140 [ 53.293736] ? _raw_spin_unlock_irq+0x27/0x70 [ 53.298200] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 53.303180] ? trace_hardirqs_on+0xd/0x10 [ 53.307291] ? _raw_spin_unlock_irq+0x27/0x70 [ 53.311753] ? acct_collect+0x637/0x800 [ 53.315691] do_exit+0x481/0x1af0 [ 53.319116] ? mm_update_next_owner+0x930/0x930 [ 53.323754] ? lock_downgrade+0x990/0x990 [ 53.327868] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 53.333196] ? futex_wait+0x3ad/0x990 [ 53.336961] ? do_raw_spin_trylock+0x190/0x190 [ 53.341508] ? fault_in_user_writeable+0x90/0x90 [ 53.346233] ? futex_wake+0x680/0x680 [ 53.349999] ? fault_in_user_writeable+0x90/0x90 [ 53.354725] ? check_noncircular+0x20/0x20 [ 53.358925] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 53.363993] ? futex_wait+0x69e/0x990 [ 53.367761] ? futex_wait_setup+0x3d0/0x3d0 [ 53.372048] ? find_held_lock+0x39/0x1d0 [ 53.376074] ? lock_downgrade+0x990/0x990 [ 53.380188] ? recalc_sigpending_tsk+0x117/0x150 [ 53.384906] ? recalc_sigpending+0x103/0x160 [ 53.389277] ? recalc_sigpending_tsk+0x150/0x150 [ 53.393994] ? get_signal+0x2b2/0x16d0 [ 53.397854] do_group_exit+0x149/0x400 [ 53.401706] ? __lock_is_held+0xbc/0x140 [ 53.405728] ? SyS_exit+0x30/0x30 [ 53.409150] ? _raw_spin_unlock_irq+0x27/0x70 [ 53.413607] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 53.418586] get_signal+0x73f/0x16d0 [ 53.422264] ? ptrace_notify+0x130/0x130 [ 53.426295] do_signal+0x94/0x1ee0 [ 53.429808] ? setup_sigcontext+0x7d0/0x7d0 [ 53.434097] ? find_held_lock+0x39/0x1d0 [ 53.438121] ? __compat_get_timespec+0xd9/0x120 [ 53.442756] ? exit_to_usermode_loop+0x8c/0x310 [ 53.447390] exit_to_usermode_loop+0x214/0x310 [ 53.451937] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 53.457437] ? lock_acquire+0x1d5/0x580 [ 53.461377] ? do_fast_syscall_32+0x158/0xf05 [ 53.465841] do_fast_syscall_32+0x83e/0xf05 [ 53.470126] ? compat_start_thread+0x80/0x80 [ 53.474499] ? do_int80_syscall_32+0x940/0x940 [ 53.479044] ? lockdep_sys_exit+0x47/0xf0 [ 53.483155] ? syscall_return_slowpath+0x2b3/0x510 [ 53.488048] ? finish_task_switch+0x1aa/0x740 [ 53.492514] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 53.497500] ? sysret32_from_system_call+0x5/0x3b [ 53.502308] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 53.507116] entry_SYSENTER_compat+0x51/0x60 [ 53.511490] RIP: 0023:0xf7fabc79 [ 53.514818] RSP: 002b:00000000f7f6512c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0 [ 53.522496] RAX: fffffffffffffe00 RBX: 00000000081280f8 RCX: 0000000000000000 [ 53.529740] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 53.536973] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 53.544208] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 53.551442] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 53.558681] [ 53.560275] Allocated by task 6883: [ 53.563867] save_stack_trace+0x16/0x20 [ 53.567813] save_stack+0x43/0xd0 [ 53.571245] kasan_kmalloc+0xad/0xe0 [ 53.574928] kmem_cache_alloc_trace+0x136/0x750 [ 53.579559] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 53.584624] futex_requeue+0x1887/0x2370 [ 53.588646] do_futex+0x7f5/0x20d0 [ 53.592152] compat_SyS_futex+0x27f/0x380 [ 53.596277] do_fast_syscall_32+0x3f2/0xf05 [ 53.600569] entry_SYSENTER_compat+0x51/0x60 [ 53.604940] [ 53.606530] Freed by task 6853: [ 53.609775] save_stack_trace+0x16/0x20 [ 53.613714] save_stack+0x43/0xd0 [ 53.617138] kasan_slab_free+0x71/0xc0 [ 53.620996] kfree+0xca/0x250 [ 53.624071] put_pi_state+0x3f4/0x560 [ 53.627833] unqueue_me_pi+0x4a/0xc0 [ 53.631511] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 53.637271] do_futex+0x825/0x20d0 [ 53.640776] compat_SyS_futex+0x27f/0x380 [ 53.644898] do_fast_syscall_32+0x3f2/0xf05 [ 53.649191] entry_SYSENTER_compat+0x51/0x60 [ 53.653559] [ 53.655154] The buggy address belongs to the object at ffff8801c4b40640 [ 53.655154] which belongs to the cache kmalloc-256 of size 256 [ 53.667780] The buggy address is located 40 bytes inside of [ 53.667780] 256-byte region [ffff8801c4b40640, ffff8801c4b40740) [ 53.679528] The buggy address belongs to the page: [ 53.684419] page:ffffea000712d000 count:1 mapcount:0 mapping:ffff8801c4b40000 index:0x0 [ 53.692526] flags: 0x200000000000100(slab) [ 53.696725] raw: 0200000000000100 ffff8801c4b40000 0000000000000000 000000010000000c [ 53.704570] raw: ffffea000713f620 ffffea000716ea60 ffff8801dac007c0 0000000000000000 [ 53.712415] page dumped because: kasan: bad access detected [ 53.718094] [ 53.719687] Memory state around the buggy address: [ 53.724589] ffff8801c4b40500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 53.731909] ffff8801c4b40580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 53.739240] >ffff8801c4b40600: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 53.746565] ^ [ 53.753280] ffff8801c4b40680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 53.760613] ffff8801c4b40700: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 53.767942] ================================================================== [ 53.775263] Disabling lock debugging due to kernel taint [ 53.780673] Kernel panic - not syncing: panic_on_warn set ... [ 53.780673] [ 53.787999] CPU: 0 PID: 6856 Comm: syz-executor5 Tainted: G B 4.14.0-rc3+ #24 [ 53.796365] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.805681] Call Trace: [ 53.808236] dump_stack+0x194/0x257 [ 53.811835] ? arch_local_irq_restore+0x53/0x53 [ 53.816467] ? vprintk_default+0x28/0x30 [ 53.820492] ? __lock_acquire+0x3ff0/0x4620 [ 53.824781] panic+0x1e4/0x417 [ 53.827952] ? __warn+0x1d9/0x1d9 [ 53.831382] ? __lock_acquire+0x407b/0x4620 [ 53.835668] kasan_end_report+0x50/0x50 [ 53.839612] kasan_report+0x144/0x340 [ 53.843379] __asan_report_load8_noabort+0x14/0x20 [ 53.848273] __lock_acquire+0x407b/0x4620 [ 53.852391] ? unwind_dump+0x4c0/0x4c0 [ 53.856250] ? __kernel_text_address+0xd/0x40 [ 53.860710] ? unwind_get_return_address+0x61/0xa0 [ 53.865607] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 53.870760] ? __save_stack_trace+0x61/0xd0 [ 53.875057] ? get_signal+0x73f/0x16d0 [ 53.878919] ? save_stack_trace+0x16/0x20 [ 53.883031] ? __lock_acquire+0x20fd/0x4620 [ 53.887317] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 53.892471] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 53.897627] ? save_stack_trace+0x16/0x20 [ 53.901738] ? __lock_acquire+0x20fd/0x4620 [ 53.906023] ? osq_unlock+0x350/0x350 [ 53.909788] ? save_stack_trace+0x16/0x20 [ 53.913911] ? check_noncircular+0x20/0x20 [ 53.918114] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 53.923270] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 53.928423] ? __unwind_start+0x169/0x330 [ 53.932534] ? find_held_lock+0x39/0x1d0 [ 53.936559] ? lock_downgrade+0x990/0x990 [ 53.940680] ? check_noncircular+0x20/0x20 [ 53.944891] lock_acquire+0x1d5/0x580 [ 53.948655] ? exit_pi_state_list+0x369/0x7a0 [ 53.953114] ? lock_release+0xd70/0xd70 [ 53.957050] ? do_raw_spin_trylock+0x190/0x190 [ 53.961595] ? find_held_lock+0x39/0x1d0 [ 53.965626] _raw_spin_lock_irq+0x5e/0x80 [ 53.969740] ? exit_pi_state_list+0x369/0x7a0 [ 53.974197] exit_pi_state_list+0x369/0x7a0 [ 53.978486] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 53.984513] ? lock_release+0xd70/0xd70 [ 53.988462] ? check_same_owner+0x320/0x320 [ 53.992750] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 53.997817] ? __might_sleep+0x95/0x190 [ 54.001759] ? __might_fault+0x188/0x1d0 [ 54.005783] ? do_raw_spin_trylock+0x190/0x190 [ 54.010331] mm_release+0x46d/0x590 [ 54.013921] ? do_raw_spin_trylock+0x190/0x190 [ 54.018469] ? mm_access+0x140/0x140 [ 54.022145] ? _raw_spin_unlock_irq+0x27/0x70 [ 54.026603] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 54.031584] ? trace_hardirqs_on+0xd/0x10 [ 54.035695] ? _raw_spin_unlock_irq+0x27/0x70