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-mmots-kasan-gce-4,10.128.0.37' (ECDSA) to the list of known hosts. 2017/09/30 01:21:44 parsed 1 programs 2017/09/30 01:21:44 executed programs: 0 syzkaller login: [ 41.205198] ================================================================== [ 41.212602] BUG: KASAN: use-after-free in __lock_acquire+0x407b/0x4620 [ 41.219239] Read of size 8 at addr ffff8801d9468d68 by task syz-executor0/5846 [ 41.226571] [ 41.228174] CPU: 1 PID: 5846 Comm: syz-executor0 Not tainted 4.14.0-rc2-mm1+ #11 [ 41.235681] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.245009] Call Trace: [ 41.247576] dump_stack+0x194/0x257 2017/09/30 01:21:49 executed programs: 721 [ 41.251180] ? arch_local_irq_restore+0x53/0x53 [ 41.255832] ? show_regs_print_info+0x65/0x65 [ 41.260312] ? __kernel_text_address+0xd/0x40 [ 41.264787] ? __lock_acquire+0x407b/0x4620 [ 41.269081] print_address_description+0x73/0x250 [ 41.273891] ? __lock_acquire+0x407b/0x4620 [ 41.278178] kasan_report+0x25b/0x340 [ 41.281958] __asan_report_load8_noabort+0x14/0x20 [ 41.286873] __lock_acquire+0x407b/0x4620 [ 41.290995] ? unwind_dump+0x4c0/0x4c0 [ 41.294852] ? __unwind_start+0x169/0x330 [ 41.298968] ? __kernel_text_address+0xd/0x40 [ 41.303434] ? unwind_get_return_address+0x61/0xa0 [ 41.308347] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 41.313518] ? unwind_get_return_address+0x61/0xa0 [ 41.318423] ? __save_stack_trace+0x61/0xd0 [ 41.322711] ? get_signal+0x73f/0x16d0 [ 41.326565] ? save_stack_trace+0x16/0x20 [ 41.330678] ? __lock_acquire+0x20fd/0x4620 [ 41.334989] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 41.340164] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 41.345330] ? save_stack_trace+0x16/0x20 [ 41.349446] ? __lock_acquire+0x20fd/0x4620 [ 41.353734] ? osq_unlock+0x350/0x350 [ 41.357501] ? save_stack_trace+0x16/0x20 [ 41.361623] ? lock_release+0xd70/0xd70 [ 41.365581] ? check_noncircular+0x20/0x20 [ 41.369794] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 41.374964] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 41.380138] ? find_held_lock+0x39/0x1d0 [ 41.384175] ? lock_downgrade+0x990/0x990 [ 41.388293] ? check_noncircular+0x20/0x20 [ 41.392507] lock_acquire+0x1d5/0x580 [ 41.396289] ? exit_pi_state_list+0x369/0x7a0 [ 41.400762] ? lock_release+0xd70/0xd70 [ 41.404702] ? do_raw_spin_trylock+0x190/0x190 [ 41.409249] ? find_held_lock+0x39/0x1d0 [ 41.413293] _raw_spin_lock_irq+0x5e/0x80 [ 41.417424] ? exit_pi_state_list+0x369/0x7a0 [ 41.421897] exit_pi_state_list+0x369/0x7a0 [ 41.426198] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 41.432230] ? lock_release+0xd70/0xd70 [ 41.436177] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 41.442042] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 41.447125] ? __might_sleep+0x95/0x190 [ 41.451076] ? __might_fault+0x188/0x1d0 [ 41.455107] ? do_raw_spin_trylock+0x190/0x190 [ 41.459663] mm_release+0x46d/0x590 [ 41.463260] ? do_raw_spin_trylock+0x190/0x190 [ 41.467808] ? mm_access+0x140/0x140 [ 41.471487] ? _raw_spin_unlock_irq+0x27/0x70 [ 41.475952] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 41.480939] ? trace_hardirqs_on+0xd/0x10 [ 41.485058] ? _raw_spin_unlock_irq+0x27/0x70 [ 41.489528] ? acct_collect+0x637/0x800 [ 41.493470] do_exit+0x481/0x1b00 [ 41.496904] ? mm_update_next_owner+0x930/0x930 [ 41.501548] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 41.507408] ? find_held_lock+0x39/0x1d0 [ 41.511450] ? refill_pi_state_cache.part.6+0x2f0/0x2f0 [ 41.516794] ? check_noncircular+0x20/0x20 [ 41.520999] ? fault_in_user_writeable+0x90/0x90 [ 41.525731] ? futex_wake+0x680/0x680 [ 41.529514] ? find_held_lock+0x39/0x1d0 [ 41.533545] ? lock_downgrade+0x990/0x990 [ 41.537658] ? recalc_sigpending_tsk+0x117/0x150 [ 41.542377] ? recalc_sigpending+0x103/0x160 [ 41.546755] ? recalc_sigpending_tsk+0x150/0x150 [ 41.551475] ? get_signal+0x2b2/0x16d0 [ 41.555331] do_group_exit+0x149/0x400 [ 41.559184] ? __lock_is_held+0xbc/0x140 [ 41.563211] ? SyS_exit+0x30/0x30 [ 41.566631] ? _raw_spin_unlock_irq+0x27/0x70 [ 41.571093] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 41.576075] get_signal+0x73f/0x16d0 [ 41.579757] ? ptrace_notify+0x130/0x130 [ 41.583787] ? vma_wants_writenotify+0x3b0/0x3b0 [ 41.588513] ? exit_robust_list+0x240/0x240 [ 41.592800] ? lock_downgrade+0x990/0x990 [ 41.596915] ? SyS_brk+0x6f0/0x6f0 [ 41.600424] do_signal+0x94/0x1ee0 [ 41.603929] ? arch_get_unmapped_area+0x750/0x750 [ 41.608736] ? lock_acquire+0x1d5/0x580 [ 41.612680] ? find_held_lock+0x39/0x1d0 [ 41.616711] ? setup_sigcontext+0x7d0/0x7d0 [ 41.621000] ? lock_downgrade+0x990/0x990 [ 41.625124] ? down_write+0x120/0x120 [ 41.628890] ? lock_release+0xd70/0xd70 [ 41.632833] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 41.638689] ? vm_mmap_pgoff+0x1fc/0x280 [ 41.642716] ? exit_to_usermode_loop+0x8c/0x310 [ 41.647358] exit_to_usermode_loop+0x214/0x310 [ 41.651908] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 41.657413] ? kasan_check_write+0x14/0x20 [ 41.661621] syscall_return_slowpath+0x42f/0x510 [ 41.666342] ? prepare_exit_to_usermode+0x2d0/0x2d0 [ 41.671326] ? entry_SYSCALL_64_fastpath+0x91/0xbe [ 41.676226] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 41.681212] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 41.685935] entry_SYSCALL_64_fastpath+0xbc/0xbe [ 41.690662] RIP: 0033:0x4520a9 [ 41.693823] RSP: 002b:00007fed82513cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 41.701494] RAX: fffffffffffffe00 RBX: 0000000000718028 RCX: 00000000004520a9 [ 41.708734] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000718028 [ 41.715972] RBP: 0000000000718000 R08: 0000000000000000 R09: 0000000000000000 [ 41.723207] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 41.730442] R13: 00007ffd833b884f R14: 00007fed825149c0 R15: 0000000000000000 [ 41.737680] [ 41.739276] Allocated by task 5869: [ 41.742868] save_stack_trace+0x16/0x20 [ 41.746809] save_stack+0x43/0xd0 [ 41.750224] kasan_kmalloc+0xad/0xe0 [ 41.753905] kmem_cache_alloc_trace+0x136/0x750 [ 41.758537] refill_pi_state_cache.part.6+0xa5/0x2f0 [ 41.763604] futex_requeue+0x1887/0x2370 [ 41.767628] do_futex+0x7f5/0x20d0 [ 41.771131] SyS_futex+0x260/0x390 [ 41.774635] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 41.779351] [ 41.780944] Freed by task 5855: [ 41.784188] save_stack_trace+0x16/0x20 [ 41.788126] save_stack+0x43/0xd0 [ 41.791542] kasan_slab_free+0x71/0xc0 [ 41.795394] kfree+0xca/0x250 [ 41.798465] put_pi_state+0x3f4/0x560 [ 41.802230] unqueue_me_pi+0x4a/0xc0 [ 41.805908] futex_wait_requeue_pi.constprop.19+0xc7f/0x1300 [ 41.811668] do_futex+0x825/0x20d0 [ 41.815172] SyS_futex+0x260/0x390 [ 41.818676] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 41.823402] [ 41.824996] The buggy address belongs to the object at ffff8801d9468d40 [ 41.824996] which belongs to the cache kmalloc-256 of size 256 [ 41.837618] The buggy address is located 40 bytes inside of [ 41.837618] 256-byte region [ffff8801d9468d40, ffff8801d9468e40) [ 41.849365] The buggy address belongs to the page: [ 41.854260] page:ffffea0007651a00 count:1 mapcount:0 mapping:ffff8801d94680c0 index:0x0 [ 41.862362] flags: 0x200000000000100(slab) [ 41.866566] raw: 0200000000000100 ffff8801d94680c0 0000000000000000 000000010000000c [ 41.874424] raw: ffffea00076666a0 ffff8801dac01650 ffff8801dac007c0 0000000000000000 [ 41.882269] page dumped because: kasan: bad access detected [ 41.887942] [ 41.889533] Memory state around the buggy address: [ 41.894425] ffff8801d9468c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 41.901747] ffff8801d9468c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 41.909075] >ffff8801d9468d00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 41.916396] ^ [ 41.923121] ffff8801d9468d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 41.930443] ffff8801d9468e00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 41.937764] ================================================================== [ 41.945084] Disabling lock debugging due to kernel taint [ 41.950496] Kernel panic - not syncing: panic_on_warn set ... [ 41.950496] [ 41.957823] CPU: 1 PID: 5846 Comm: syz-executor0 Tainted: G B 4.14.0-rc2-mm1+ #11 [ 41.966534] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.975850] Call Trace: [ 41.978405] dump_stack+0x194/0x257 [ 41.981997] ? arch_local_irq_restore+0x53/0x53 [ 41.986633] ? vprintk_default+0x28/0x30 [ 41.990661] ? __lock_acquire+0x4060/0x4620 [ 41.994949] panic+0x1e4/0x41c [ 41.998107] ? refcount_error_report+0x214/0x214 [ 42.002852] ? __lock_acquire+0x407b/0x4620 [ 42.007140] kasan_end_report+0x50/0x50 [ 42.011087] kasan_report+0x144/0x340 [ 42.014862] __asan_report_load8_noabort+0x14/0x20 [ 42.019762] __lock_acquire+0x407b/0x4620 [ 42.023881] ? unwind_dump+0x4c0/0x4c0 [ 42.027736] ? __unwind_start+0x169/0x330 [ 42.031853] ? __kernel_text_address+0xd/0x40 [ 42.036320] ? unwind_get_return_address+0x61/0xa0 [ 42.041245] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 42.046407] ? unwind_get_return_address+0x61/0xa0 [ 42.051309] ? __save_stack_trace+0x61/0xd0 [ 42.055599] ? get_signal+0x73f/0x16d0 [ 42.059455] ? save_stack_trace+0x16/0x20 [ 42.063572] ? __lock_acquire+0x20fd/0x4620 [ 42.067863] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 42.073031] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 42.078201] ? save_stack_trace+0x16/0x20 [ 42.082328] ? __lock_acquire+0x20fd/0x4620 [ 42.086622] ? osq_unlock+0x350/0x350 [ 42.090394] ? save_stack_trace+0x16/0x20 [ 42.094514] ? lock_release+0xd70/0xd70 [ 42.098457] ? check_noncircular+0x20/0x20 [ 42.102657] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 42.107813] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 42.112970] ? find_held_lock+0x39/0x1d0 [ 42.116998] ? lock_downgrade+0x990/0x990 [ 42.121117] ? check_noncircular+0x20/0x20 [ 42.125316] lock_acquire+0x1d5/0x580 [ 42.129085] ? exit_pi_state_list+0x369/0x7a0 [ 42.133545] ? lock_release+0xd70/0xd70 [ 42.137482] ? do_raw_spin_trylock+0x190/0x190 [ 42.142031] ? find_held_lock+0x39/0x1d0 [ 42.146062] _raw_spin_lock_irq+0x5e/0x80 [ 42.150175] ? exit_pi_state_list+0x369/0x7a0 [ 42.154633] exit_pi_state_list+0x369/0x7a0 [ 42.158922] ? futex_wait_requeue_pi.constprop.19+0x1300/0x1300 [ 42.164948] ? lock_release+0xd70/0xd70 [ 42.168890] ? trace_event_raw_event_sched_switch+0x770/0x770 [ 42.174740] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 42.179810] ? __might_sleep+0x95/0x190 [ 42.183751] ? __might_fault+0x188/0x1d0 [ 42.187777] ? do_raw_spin_trylock+0x190/0x190 [ 42.192327] mm_release+0x46d/0x590 [ 42.195927] ? do_raw_spin_trylock+0x190/0x190 [ 42.200472] ? mm_access+0x140/0x140 [ 42.204151] ? _raw_spin_unlock_irq+0x27/0x70