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-386-4,10.128.15.218' (ECDSA) to the list of known hosts. 2017/10/02 20:38:48 parsed 1 programs 2017/10/02 20:38:48 executed programs: 0 2017/10/02 20:38:53 executed programs: 44 2017/10/02 20:38:58 executed programs: 89 2017/10/02 20:39:03 executed programs: 134 2017/10/02 20:39:08 executed programs: 179 2017/10/02 20:39:13 executed programs: 224 2017/10/02 20:39:18 executed programs: 269 2017/10/02 20:39:23 executed programs: 314 2017/10/02 20:39:29 executed programs: 359 2017/10/02 20:39:34 executed programs: 404 2017/10/02 20:39:39 executed programs: 449 2017/10/02 20:39:44 executed programs: 494 2017/10/02 20:39:49 executed programs: 539 2017/10/02 20:39:54 executed programs: 584 syzkaller login: [ 202.568194] ================================================================== [ 202.575581] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 202.582212] Read of size 8 at addr ffff8801c950ade8 by task syz-executor0/6669 [ 202.589531] [ 202.591126] CPU: 0 PID: 6669 Comm: syz-executor0 Not tainted 4.14.0-rc3+ #22 [ 202.598276] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 202.607595] Call Trace: [ 202.610161] dump_stack+0x194/0x257 [ 202.613756] ? arch_local_irq_restore+0x53/0x53 [ 202.618394] ? show_regs_print_info+0x65/0x65 [ 202.622855] ? __kernel_text_address+0xd/0x40 [ 202.627316] ? __lock_acquire+0x407b/0x4620 [ 202.631603] print_address_description+0x73/0x250 [ 202.636410] ? __lock_acquire+0x407b/0x4620 [ 202.640694] kasan_report+0x25b/0x340 [ 202.644459] __asan_report_load8_noabort+0x14/0x20 [ 202.649355] __lock_acquire+0x407b/0x4620 [ 202.653468] ? unwind_dump+0x4c0/0x4c0 [ 202.657319] ? __kernel_text_address+0xd/0x40 [ 202.661779] ? unwind_get_return_address+0x61/0xa0 [ 202.666674] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 202.671827] ? __save_stack_trace+0x61/0xd0 [ 202.676114] ? get_signal+0x73f/0x16d0 [ 202.679965] ? save_stack_trace+0x16/0x20 [ 202.684075] ? __lock_acquire+0x20fd/0x4620 [ 202.688359] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 202.693514] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 202.698670] ? save_stack_trace+0x16/0x20 [ 202.702781] ? __lock_acquire+0x20fd/0x4620 [ 202.707074] ? osq_unlock+0x350/0x350 [ 202.710838] ? save_stack_trace+0x16/0x20 [ 202.714951] ? check_noncircular+0x20/0x20 [ 202.719148] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 202.724304] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 202.729459] ? __unwind_start+0x169/0x330 [ 202.733572] ? find_held_lock+0x39/0x1d0 [ 202.737599] ? lock_downgrade+0x990/0x990 [ 202.741708] ? check_noncircular+0x20/0x20 [ 202.745907] lock_acquire+0x1d5/0x580 [ 202.749673] ? exit_pi_state_list+0x369/0x7a0 [ 202.754133] ? lock_release+0xd70/0xd70 [ 202.758071] ? do_raw_spin_trylock+0x190/0x190 [ 202.762616] ? find_held_lock+0x39/0x1d0 [ 202.766646] _raw_spin_lock_irq+0x5e/0x80 [ 202.770756] ? exit_pi_state_list+0x369/0x7a0 [ 202.775216] exit_pi_state_list+0x369/0x7a0 [ 202.779506] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 202.785528] ? lock_release+0xd70/0xd70 [ 202.789468] ? check_same_owner+0x320/0x320 [ 202.793752] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 202.798820] ? __might_sleep+0x95/0x190 [ 202.802760] ? __might_fault+0x188/0x1d0 [ 202.806789] ? do_raw_spin_trylock+0x190/0x190 [ 202.811338] mm_release+0x46d/0x590 [ 202.814930] ? do_raw_spin_trylock+0x190/0x190 [ 202.819477] ? mm_access+0x140/0x140 [ 202.823155] ? _raw_spin_unlock_irq+0x27/0x70 [ 202.827615] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 202.832597] ? trace_hardirqs_on+0xd/0x10 [ 202.836716] ? _raw_spin_unlock_irq+0x27/0x70 [ 202.841174] ? acct_collect+0x637/0x800 [ 202.845111] do_exit+0x481/0x1af0 [ 202.848528] ? mm_update_next_owner+0x930/0x930 [ 202.853162] ? lock_downgrade+0x990/0x990 [ 202.857273] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 202.862601] ? futex_wait+0x3ad/0x990 [ 202.866369] ? do_raw_spin_trylock+0x190/0x190 [ 202.870916] ? fault_in_user_writeable+0x90/0x90 [ 202.875637] ? futex_wake+0x680/0x680 [ 202.879404] ? fault_in_user_writeable+0x90/0x90 [ 202.884124] ? check_noncircular+0x20/0x20 [ 202.888324] ? drop_futex_key_refs.isra.13+0x63/0xb0 [ 202.893390] ? futex_wait+0x69e/0x990 [ 202.897156] ? futex_wait_setup+0x3d0/0x3d0 [ 202.901443] ? find_held_lock+0x39/0x1d0 [ 202.905471] ? lock_downgrade+0x990/0x990 [ 202.909585] ? recalc_sigpending_tsk+0x117/0x150 [ 202.914307] ? recalc_sigpending+0x103/0x160 [ 202.918683] ? recalc_sigpending_tsk+0x150/0x150 [ 202.923402] ? get_signal+0x2b2/0x16d0 [ 202.927258] do_group_exit+0x149/0x400 [ 202.931110] ? __lock_is_held+0xbc/0x140 [ 202.935135] ? SyS_exit+0x30/0x30 [ 202.938557] ? _raw_spin_unlock_irq+0x27/0x70 [ 202.943026] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 202.948006] get_signal+0x73f/0x16d0 [ 202.951686] ? ptrace_notify+0x130/0x130 [ 202.955714] ? check_noncircular+0x20/0x20 [ 202.959918] do_signal+0x94/0x1ee0 [ 202.963424] ? find_held_lock+0x39/0x1d0 [ 202.967454] ? setup_sigcontext+0x7d0/0x7d0 [ 202.971739] ? lock_downgrade+0x990/0x990 [ 202.975852] ? free_pidmap.isra.0+0x70/0x70 [ 202.980140] ? lock_release+0xd70/0xd70 [ 202.984079] ? __compat_get_timespec+0xd9/0x120 [ 202.988713] ? exit_to_usermode_loop+0x8c/0x310 [ 202.993346] exit_to_usermode_loop+0x214/0x310 [ 202.997895] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 203.003395] ? lock_acquire+0x1d5/0x580 [ 203.007333] ? do_fast_syscall_32+0x158/0xf05 [ 203.011795] do_fast_syscall_32+0x83e/0xf05 [ 203.016082] ? compat_start_thread+0x80/0x80 [ 203.020457] ? do_int80_syscall_32+0x940/0x940 [ 203.025005] ? lockdep_sys_exit+0x47/0xf0 [ 203.029129] ? syscall_return_slowpath+0x2b3/0x510 [ 203.034024] ? finish_task_switch+0x1aa/0x740 [ 203.038484] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 203.043468] ? sysret32_from_system_call+0x5/0x3b [ 203.048289] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 203.053096] entry_SYSENTER_compat+0x51/0x60 [ 203.057468] RIP: 0023:0xf7fa1c79 [ 203.060796] RSP: 002b:00000000f7f5b12c EFLAGS: 00000292 ORIG_RAX: 00000000000000f0 [ 203.068468] RAX: fffffffffffffe00 RBX: 00000000081280f8 RCX: 0000000000000000 [ 203.075702] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 203.082938] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 203.090175] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 203.097411] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 203.104652] [ 203.106245] Allocated by task 6670: [ 203.109838] save_stack_trace+0x16/0x20 [ 203.113776] save_stack+0x43/0xd0 [ 203.117198] kasan_kmalloc+0xad/0xe0 [ 203.120887] kmem_cache_alloc_trace+0x136/0x750 [ 203.125521] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 203.130596] futex_requeue+0x1887/0x2370 [ 203.134619] do_futex+0x7f5/0x20d0 [ 203.138122] compat_SyS_futex+0x27f/0x380 [ 203.142236] do_fast_syscall_32+0x3f2/0xf05 [ 203.146520] entry_SYSENTER_compat+0x51/0x60 [ 203.150889] [ 203.152484] Freed by task 6668: [ 203.155729] save_stack_trace+0x16/0x20 [ 203.159676] save_stack+0x43/0xd0 [ 203.163092] kasan_slab_free+0x71/0xc0 [ 203.166945] kfree+0xca/0x250 [ 203.170016] put_pi_state+0x3f4/0x560 [ 203.173778] unqueue_me_pi+0x4a/0xc0 [ 203.177457] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 203.183216] do_futex+0x825/0x20d0 [ 203.186719] compat_SyS_futex+0x27f/0x380 [ 203.190830] do_fast_syscall_32+0x3f2/0xf05 [ 203.195115] entry_SYSENTER_compat+0x51/0x60 [ 203.199484] [ 203.201079] The buggy address belongs to the object at ffff8801c950adc0 [ 203.201079] which belongs to the cache kmalloc-256 of size 256 [ 203.213697] The buggy address is located 40 bytes inside of [ 203.213697] 256-byte region [ffff8801c950adc0, ffff8801c950aec0) [ 203.225445] The buggy address belongs to the page: [ 203.230340] page:ffffea0007254280 count:1 mapcount:0 mapping:ffff8801c950a000 index:0x0 [ 203.238446] flags: 0x200000000000100(slab) [ 203.242648] raw: 0200000000000100 ffff8801c950a000 0000000000000000 000000010000000c [ 203.250495] raw: ffffea000726cf60 ffffea000726d060 ffff8801dac007c0 0000000000000000 [ 203.258337] page dumped because: kasan: bad access detected [ 203.264007] [ 203.265599] Memory state around the buggy address: [ 203.270491] ffff8801c950ac80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 203.277821] ffff8801c950ad00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 203.285142] >ffff8801c950ad80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 203.292463] ^ [ 203.299188] ffff8801c950ae00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 203.306513] ffff8801c950ae80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 203.313834] ================================================================== [ 203.321163] Disabling lock debugging due to kernel taint [ 203.326584] Kernel panic - not syncing: panic_on_warn set ... [ 203.326584] [ 203.333911] CPU: 0 PID: 6669 Comm: syz-executor0 Tainted: G B 4.14.0-rc3+ #22 [ 203.342277] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 203.351596] Call Trace: [ 203.354152] dump_stack+0x194/0x257 [ 203.357747] ? arch_local_irq_restore+0x53/0x53 [ 203.362382] ? vprintk_default+0x28/0x30 [ 203.366411] ? __lock_acquire+0x3ff0/0x4620 [ 203.370697] panic+0x1e4/0x417 [ 203.373854] ? __warn+0x1d9/0x1d9 [ 203.377275] ? __lock_acquire+0x407b/0x4620 [ 203.381561] kasan_end_report+0x50/0x50 [ 203.385499] kasan_report+0x144/0x340 [ 203.389267] __asan_report_load8_noabort+0x14/0x20 [ 203.394161] __lock_acquire+0x407b/0x4620 [ 203.398274] ? unwind_dump+0x4c0/0x4c0 [ 203.402128] ? __kernel_text_address+0xd/0x40 [ 203.406589] ? unwind_get_return_address+0x61/0xa0 [ 203.411488] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 203.416641] ? __save_stack_trace+0x61/0xd0 [ 203.420930] ? get_signal+0x73f/0x16d0 [ 203.424782] ? save_stack_trace+0x16/0x20 [ 203.428895] ? __lock_acquire+0x20fd/0x4620 [ 203.433184] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 203.438366] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 203.443522] ? save_stack_trace+0x16/0x20 [ 203.447636] ? __lock_acquire+0x20fd/0x4620 [ 203.451925] ? osq_unlock+0x350/0x350 [ 203.455694] ? save_stack_trace+0x16/0x20 [ 203.459811] ? check_noncircular+0x20/0x20 [ 203.464012] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 203.469170] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 203.474325] ? __unwind_start+0x169/0x330 [ 203.478441] ? find_held_lock+0x39/0x1d0 [ 203.482470] ? lock_downgrade+0x990/0x990 [ 203.486582] ? check_noncircular+0x20/0x20 [ 203.490783] lock_acquire+0x1d5/0x580 [ 203.494550] ? exit_pi_state_list+0x369/0x7a0 [ 203.499011] ? lock_release+0xd70/0xd70 [ 203.502950] ? do_raw_spin_trylock+0x190/0x190 [ 203.507496] ? find_held_lock+0x39/0x1d0 [ 203.511528] _raw_spin_lock_irq+0x5e/0x80 [ 203.515640] ? exit_pi_state_list+0x369/0x7a0 [ 203.520101] exit_pi_state_list+0x369/0x7a0 [ 203.524391] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 203.530417] ? lock_release+0xd70/0xd70 [ 203.534361] ? check_same_owner+0x320/0x320 [ 203.538649] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 203.543718] ? __might_sleep+0x95/0x190 [ 203.547665] ? __might_fault+0x188/0x1d0 [ 203.551695] ? do_raw_spin_trylock+0x190/0x190 [ 203.556247] mm_release+0x46d/0x590 [ 203.559847] ? do_raw_spin_trylock+0x190/0x190 [ 203.564395] ? mm_access+0x140/0x140 [ 203.568073] ? _raw_spin_unlock_irq+0x27/0x70