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-386-2,10.128.15.194' (ECDSA) to the list of known hosts. 2017/10/04 13:44:00 parsed 1 programs 2017/10/04 13:44:00 executed programs: 0 2017/10/04 13:44:05 executed programs: 340 2017/10/04 13:44:10 executed programs: 678 2017/10/04 13:44:15 executed programs: 1017 2017/10/04 13:44:20 executed programs: 1354 2017/10/04 13:44:25 executed programs: 1691 syzkaller login: [ 124.794373] ================================================================== [ 124.801783] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 124.808427] Read of size 8 at addr ffff8801c94dd8e8 by task syz-executor6/13648 [ 124.815847] [ 124.817459] CPU: 0 PID: 13648 Comm: syz-executor6 Not tainted 4.14.0-rc3+ #24 [ 124.824707] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 124.834043] Call Trace: [ 124.836609] dump_stack+0x194/0x257 [ 124.840211] ? arch_local_irq_restore+0x53/0x53 [ 124.844861] ? show_regs_print_info+0x65/0x65 [ 124.849339] ? __kernel_text_address+0xd/0x40 [ 124.853811] ? __lock_acquire+0x407b/0x4620 [ 124.858110] print_address_description+0x73/0x250 [ 124.862934] ? __lock_acquire+0x407b/0x4620 [ 124.867230] kasan_report+0x25b/0x340 [ 124.871000] __asan_report_load8_noabort+0x14/0x20 [ 124.875908] __lock_acquire+0x407b/0x4620 [ 124.880036] ? unwind_dump+0x4c0/0x4c0 [ 124.883899] ? __kernel_text_address+0xd/0x40 [ 124.888366] ? unwind_get_return_address+0x61/0xa0 [ 124.893263] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 124.898428] ? __save_stack_trace+0x61/0xd0 [ 124.902725] ? get_signal+0x73f/0x16d0 [ 124.906582] ? save_stack_trace+0x16/0x20 [ 124.910703] ? __lock_acquire+0x20fd/0x4620 [ 124.915000] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 124.920165] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 124.925323] ? save_stack_trace+0x16/0x20 [ 124.929442] ? __lock_acquire+0x20fd/0x4620 [ 124.933733] ? osq_unlock+0x350/0x350 [ 124.937502] ? save_stack_trace+0x16/0x20 [ 124.941633] ? check_noncircular+0x20/0x20 [ 124.945850] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 124.951019] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 124.956181] ? __unwind_start+0x169/0x330 [ 124.960298] ? find_held_lock+0x39/0x1d0 [ 124.964335] ? lock_downgrade+0x990/0x990 [ 124.968461] ? check_noncircular+0x20/0x20 [ 124.972677] lock_acquire+0x1d5/0x580 [ 124.976466] ? exit_pi_state_list+0x369/0x7a0 [ 124.980942] ? lock_release+0xd70/0xd70 [ 124.984884] ? do_raw_spin_trylock+0x190/0x190 [ 124.989442] ? find_held_lock+0x39/0x1d0 [ 124.993485] _raw_spin_lock_irq+0x5e/0x80 [ 124.997602] ? exit_pi_state_list+0x369/0x7a0 [ 125.002067] exit_pi_state_list+0x369/0x7a0 [ 125.006358] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 125.012384] ? lock_release+0xd70/0xd70 [ 125.016333] ? check_same_owner+0x320/0x320 [ 125.020638] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 125.025712] ? __might_sleep+0x95/0x190 [ 125.029652] ? __might_fault+0x188/0x1d0 [ 125.033680] ? do_raw_spin_trylock+0x190/0x190 [ 125.038236] mm_release+0x46d/0x590 [ 125.041840] ? do_raw_spin_trylock+0x190/0x190 [ 125.046406] ? mm_access+0x140/0x140 [ 125.050098] ? _raw_spin_unlock_irq+0x27/0x70 [ 125.054564] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 125.059544] ? trace_hardirqs_on+0xd/0x10 [ 125.063667] ? _raw_spin_unlock_irq+0x27/0x70 [ 125.068136] ? acct_collect+0x637/0x800 [ 125.072080] do_exit+0x481/0x1af0 [ 125.075501] ? mm_update_next_owner+0x930/0x930 [ 125.080134] ? lock_downgrade+0x990/0x990 [ 125.084248] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 125.089588] ? futex_wait+0x3ad/0x990 [ 125.093375] ? do_raw_spin_trylock+0x190/0x190 [ 125.097942] ? fault_in_user_writeable+0x90/0x90 [ 125.102672] ? futex_wake+0x680/0x680 [ 125.106447] ? fault_in_user_writeable+0x90/0x90 [ 125.111178] ? check_noncircular+0x20/0x20 [ 125.115384] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 125.120457] ? futex_wait+0x69e/0x990 [ 125.124228] ? futex_wait_setup+0x3d0/0x3d0 [ 125.128522] ? find_held_lock+0x39/0x1d0 [ 125.132549] ? lock_downgrade+0x990/0x990 [ 125.136666] ? recalc_sigpending_tsk+0x117/0x150 [ 125.141399] ? recalc_sigpending+0x103/0x160 [ 125.145778] ? recalc_sigpending_tsk+0x150/0x150 [ 125.150496] ? get_signal+0x2b2/0x16d0 [ 125.154358] do_group_exit+0x149/0x400 [ 125.158213] ? __lock_is_held+0xbc/0x140 [ 125.162241] ? SyS_exit+0x30/0x30 [ 125.165664] ? _raw_spin_unlock_irq+0x27/0x70 [ 125.170126] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 125.175110] get_signal+0x73f/0x16d0 [ 125.178790] ? ptrace_notify+0x130/0x130 [ 125.182824] ? __lock_is_held+0xbc/0x140 [ 125.186865] ? __fget+0x362/0x580 [ 125.190291] ? __sched_text_start+0x8/0x8 [ 125.194407] ? iterate_fd+0x3f0/0x3f0 [ 125.198177] do_signal+0x94/0x1ee0 [ 125.201685] ? setup_sigcontext+0x7d0/0x7d0 [ 125.205979] ? __fget_light+0x29d/0x390 [ 125.209926] ? fget_raw+0x20/0x20 [ 125.213351] ? __schedule+0x2080/0x2080 [ 125.217296] ? find_held_lock+0x39/0x1d0 [ 125.221320] ? __compat_get_timespec+0xd9/0x120 [ 125.225955] ? exit_to_usermode_loop+0x8c/0x310 [ 125.230590] exit_to_usermode_loop+0x214/0x310 [ 125.235136] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 125.240636] ? lock_acquire+0x1d5/0x580 [ 125.244576] ? do_fast_syscall_32+0x158/0xf05 [ 125.249041] do_fast_syscall_32+0x83e/0xf05 [ 125.253328] ? compat_start_thread+0x80/0x80 [ 125.257700] ? do_int80_syscall_32+0x940/0x940 [ 125.262246] ? lockdep_sys_exit+0x47/0xf0 [ 125.266357] ? syscall_return_slowpath+0x2b3/0x510 [ 125.271249] ? finish_task_switch+0x1aa/0x740 [ 125.275710] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 125.280694] ? sysret32_from_system_call+0x5/0x3b [ 125.285506] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 125.290315] entry_SYSENTER_compat+0x51/0x60 [ 125.294687] RIP: 0023:0xf7f2fc79 [ 125.298020] RSP: 002b:00000000f7ee912c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0 [ 125.305698] RAX: fffffffffffffe00 RBX: 00000000081280f8 RCX: 0000000000000000 [ 125.312933] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 125.320166] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 125.327401] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 125.334635] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 125.341874] [ 125.343469] Allocated by task 13668: [ 125.347152] save_stack_trace+0x16/0x20 [ 125.351091] save_stack+0x43/0xd0 [ 125.354506] kasan_kmalloc+0xad/0xe0 [ 125.358184] kmem_cache_alloc_trace+0x136/0x750 [ 125.362816] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 125.367881] futex_requeue+0x1887/0x2370 [ 125.371905] do_futex+0x7f5/0x20d0 [ 125.375406] compat_SyS_futex+0x27f/0x380 [ 125.379516] do_fast_syscall_32+0x3f2/0xf05 [ 125.383799] entry_SYSENTER_compat+0x51/0x60 [ 125.388167] [ 125.389758] Freed by task 13639: [ 125.393087] save_stack_trace+0x16/0x20 [ 125.397029] save_stack+0x43/0xd0 [ 125.400449] kasan_slab_free+0x71/0xc0 [ 125.404298] kfree+0xca/0x250 [ 125.407368] put_pi_state+0x3f4/0x560 [ 125.411135] unqueue_me_pi+0x4a/0xc0 [ 125.414810] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 125.420569] do_futex+0x825/0x20d0 [ 125.424073] compat_SyS_futex+0x27f/0x380 [ 125.428184] do_fast_syscall_32+0x3f2/0xf05 [ 125.432468] entry_SYSENTER_compat+0x51/0x60 [ 125.436835] [ 125.438428] The buggy address belongs to the object at ffff8801c94dd8c0 [ 125.438428] which belongs to the cache kmalloc-256 of size 256 [ 125.451047] The buggy address is located 40 bytes inside of [ 125.451047] 256-byte region [ffff8801c94dd8c0, ffff8801c94dd9c0) [ 125.462795] The buggy address belongs to the page: [ 125.467686] page:ffffea0007253740 count:1 mapcount:0 mapping:ffff8801c94dd000 index:0xffff8801c94dd000 [ 125.477092] flags: 0x200000000000100(slab) [ 125.481290] raw: 0200000000000100 ffff8801c94dd000 ffff8801c94dd000 000000010000000b [ 125.489132] raw: ffffea000727b9a0 ffffea000727b760 ffff8801dac007c0 0000000000000000 [ 125.496974] page dumped because: kasan: bad access detected [ 125.502646] [ 125.504234] Memory state around the buggy address: [ 125.509127] ffff8801c94dd780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 125.516448] ffff8801c94dd800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 125.523768] >ffff8801c94dd880: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 125.531087] ^ [ 125.537801] ffff8801c94dd900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 125.545121] ffff8801c94dd980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 125.552442] ================================================================== [ 125.559762] Disabling lock debugging due to kernel taint [ 125.565173] Kernel panic - not syncing: panic_on_warn set ... [ 125.565173] [ 125.572513] CPU: 0 PID: 13648 Comm: syz-executor6 Tainted: G B 4.14.0-rc3+ #24 [ 125.580963] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 125.590281] Call Trace: [ 125.592833] dump_stack+0x194/0x257 [ 125.596428] ? arch_local_irq_restore+0x53/0x53 [ 125.601060] ? vprintk_default+0x28/0x30 [ 125.605086] ? __lock_acquire+0x3ff0/0x4620 [ 125.609378] panic+0x1e4/0x417 [ 125.612542] ? __warn+0x1d9/0x1d9 [ 125.615961] ? __lock_acquire+0x407b/0x4620 [ 125.620247] kasan_end_report+0x50/0x50 [ 125.624184] kasan_report+0x144/0x340 [ 125.627950] __asan_report_load8_noabort+0x14/0x20 [ 125.632842] __lock_acquire+0x407b/0x4620 [ 125.636955] ? unwind_dump+0x4c0/0x4c0 [ 125.640807] ? __kernel_text_address+0xd/0x40 [ 125.645266] ? unwind_get_return_address+0x61/0xa0 [ 125.650167] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 125.655322] ? __save_stack_trace+0x61/0xd0 [ 125.659612] ? get_signal+0x73f/0x16d0 [ 125.663464] ? save_stack_trace+0x16/0x20 [ 125.667575] ? __lock_acquire+0x20fd/0x4620 [ 125.671862] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 125.677023] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 125.682176] ? save_stack_trace+0x16/0x20 [ 125.686286] ? __lock_acquire+0x20fd/0x4620 [ 125.690569] ? osq_unlock+0x350/0x350 [ 125.694333] ? save_stack_trace+0x16/0x20 [ 125.698446] ? check_noncircular+0x20/0x20 [ 125.702644] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 125.707796] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 125.712949] ? __unwind_start+0x169/0x330 [ 125.717060] ? find_held_lock+0x39/0x1d0 [ 125.721088] ? lock_downgrade+0x990/0x990 [ 125.725198] ? check_noncircular+0x20/0x20 [ 125.729401] lock_acquire+0x1d5/0x580 [ 125.733166] ? exit_pi_state_list+0x369/0x7a0 [ 125.737627] ? lock_release+0xd70/0xd70 [ 125.741564] ? do_raw_spin_trylock+0x190/0x190 [ 125.746111] ? find_held_lock+0x39/0x1d0 [ 125.750140] _raw_spin_lock_irq+0x5e/0x80 [ 125.754253] ? exit_pi_state_list+0x369/0x7a0 [ 125.758711] exit_pi_state_list+0x369/0x7a0 [ 125.763002] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 125.769033] ? lock_release+0xd70/0xd70 [ 125.772970] ? check_same_owner+0x320/0x320 [ 125.777255] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 125.782324] ? __might_sleep+0x95/0x190 [ 125.786266] ? __might_fault+0x188/0x1d0 [ 125.790292] ? do_raw_spin_trylock+0x190/0x190 [ 125.794838] mm_release+0x46d/0x590