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-386-2,10.128.0.42' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 32.400334] ================================================================== [ 32.401428] BUG: KASAN: use-after-free in __lock_acquire+0x465e/0x47f0 [ 32.402313] Read of size 8 at addr ffff8801cd8e13f0 by task syzkaller236979/3086 [ 32.403318] [ 32.403547] CPU: 1 PID: 3086 Comm: syzkaller236979 Not tainted 4.15.0-rc1+ #115 [ 32.404541] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.405774] Call Trace: [ 32.406130] dump_stack+0x194/0x257 [ 32.406618] ? arch_local_irq_restore+0x53/0x53 [ 32.407240] ? show_regs_print_info+0x65/0x65 [ 32.407836] ? print_usage_bug+0x3f0/0x3f0 [ 32.408399] ? __lock_acquire+0x6e9/0x47f0 [ 32.408961] ? __lock_acquire+0x465e/0x47f0 [ 32.409535] print_address_description+0x73/0x250 [ 32.410176] ? __lock_acquire+0x465e/0x47f0 [ 32.410750] kasan_report+0x25b/0x340 [ 32.411257] __asan_report_load8_noabort+0x14/0x20 [ 32.411938] __lock_acquire+0x465e/0x47f0 [ 32.412489] ? __lock_acquire+0x6e9/0x47f0 [ 32.413055] ? update_cfs_rq_load_avg.part.70+0x2d0/0x2d0 [ 32.413803] ? print_usage_bug+0x3f0/0x3f0 [ 32.414369] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.415054] ? __lock_acquire+0x6e9/0x47f0 [ 32.415615] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.416301] ? update_cfs_rq_load_avg.part.70+0x2d0/0x2d0 [ 32.417030] ? _raw_spin_unlock_irqrestore+0xa6/0xba [ 32.417720] ? __lock_acquire+0x6e9/0x47f0 [ 32.418283] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 32.418968] ? lock_acquire+0x1d5/0x580 [ 32.419496] ? ep_free+0xf4/0x320 [ 32.419961] ? lock_release+0xda0/0xda0 [ 32.420808] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 32.426656] ? print_usage_bug+0x3f0/0x3f0 [ 32.430859] ? rcu_note_context_switch+0x710/0x710 [ 32.435753] ? __might_sleep+0x95/0x190 [ 32.439693] ? ep_free+0xf4/0x320 [ 32.443110] ? __mutex_lock+0x16f/0x1a80 [ 32.447135] ? ep_free+0xf4/0x320 [ 32.450549] ? print_usage_bug+0x3f0/0x3f0 [ 32.454748] ? ep_free+0xf4/0x320 [ 32.458169] ? print_usage_bug+0x3f0/0x3f0 [ 32.462372] lock_acquire+0x1d5/0x580 [ 32.466139] ? remove_wait_queue+0x81/0x350 [ 32.470425] ? __lock_acquire+0x6e9/0x47f0 [ 32.474622] ? lock_release+0xda0/0xda0 [ 32.478566] ? __lock_acquire+0x6e9/0x47f0 [ 32.482765] ? lock_acquire+0x1d5/0x580 [ 32.486703] ? ep_unregister_pollwait.isra.7+0x323/0x590 [ 32.492116] _raw_spin_lock_irqsave+0x96/0xc0 [ 32.496576] ? remove_wait_queue+0x81/0x350 [ 32.500859] remove_wait_queue+0x81/0x350 [ 32.504972] ? prepare_to_wait+0x4d0/0x4d0 [ 32.509173] ? rcutorture_record_progress+0x10/0x10 [ 32.514153] ? lock_release+0xda0/0xda0 [ 32.518092] ep_unregister_pollwait.isra.7+0x18c/0x590 [ 32.523335] ? __kernel_text_address+0xd/0x40 [ 32.527794] ? clear_tfile_check_list+0x370/0x370 [ 32.532601] ? check_noncircular+0x20/0x20 [ 32.536802] ? free_fs_struct+0x52/0x60 [ 32.540740] ? locks_remove_file+0x3fa/0x5a0 [ 32.545113] ep_free+0x13f/0x320 [ 32.548450] ? ep_remove+0x800/0x800 [ 32.552127] ? fsnotify_first_mark+0x2b0/0x2b0 [ 32.556673] ? ep_free+0x320/0x320 [ 32.560174] ep_eventpoll_release+0x44/0x60 [ 32.564460] __fput+0x333/0x7f0 [ 32.567704] ? fput+0x140/0x140 [ 32.570950] ? _raw_spin_unlock_irq+0x27/0x70 [ 32.575407] ____fput+0x15/0x20 [ 32.578652] task_work_run+0x199/0x270 [ 32.582504] ? task_work_cancel+0x210/0x210 [ 32.586789] ? _raw_spin_unlock+0x22/0x30 [ 32.590899] ? switch_task_namespaces+0x87/0xc0 [ 32.595532] do_exit+0x9bb/0x1ae0 [ 32.598952] ? trace_hardirqs_on+0xd/0x10 [ 32.603064] ? mm_update_next_owner+0x930/0x930 [ 32.607698] ? do_raw_spin_trylock+0x190/0x190 [ 32.612249] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 32.618096] ? _raw_spin_unlock+0x22/0x30 [ 32.622210] ? check_noncircular+0x20/0x20 [ 32.626410] ? __pmd_alloc+0x4e0/0x4e0 [ 32.630270] ? find_held_lock+0x39/0x1d0 [ 32.634295] ? find_held_lock+0x39/0x1d0 [ 32.638320] ? lock_downgrade+0x980/0x980 [ 32.642436] ? handle_mm_fault+0x410/0x8d0 [ 32.646632] ? down_read_trylock+0xdb/0x170 [ 32.651004] ? __do_page_fault+0x32d/0xc90 [ 32.655201] ? __handle_mm_fault+0x3e20/0x3e20 [ 32.659749] ? vmacache_find+0x5f/0x280 [ 32.663690] do_group_exit+0x149/0x400 [ 32.667541] ? __do_page_fault+0x3d6/0xc90 [ 32.671738] ? SyS_exit+0x30/0x30 [ 32.675158] ? do_fast_syscall_32+0x156/0xf9d [ 32.679616] ? do_group_exit+0x400/0x400 [ 32.683640] SyS_exit_group+0x1d/0x20 [ 32.687404] do_fast_syscall_32+0x3ee/0xf9d [ 32.691691] ? do_int80_syscall_32+0x9d0/0x9d0 [ 32.696236] ? kasan_check_read+0x11/0x20 [ 32.700347] ? syscall_return_slowpath+0x550/0x550 [ 32.705241] ? SyS_rt_sigaction+0x94/0x1b0 [ 32.709439] ? lockdep_sys_exit+0x47/0xf0 [ 32.713548] ? retint_user+0x18/0x18 [ 32.717574] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 32.722382] entry_SYSENTER_compat+0x51/0x60 [ 32.726752] RIP: 0023:0xf7f97c79 [ 32.730078] RSP: 002b:00000000ffcb51bc EFLAGS: 00000296 ORIG_RAX: 00000000000000fc [ 32.737748] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000080f0298 [ 32.744982] RDX: 0000000000000000 RSI: 00000000080d9b18 RDI: 00000000080f02a0 [ 32.752215] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 [ 32.759448] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 32.766680] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 32.773917] [ 32.775510] Allocated by task 3086: [ 32.779102] save_stack+0x43/0xd0 [ 32.782524] kasan_kmalloc+0xad/0xe0 [ 32.786204] kmem_cache_alloc_trace+0x136/0x750 [ 32.790837] binder_get_thread+0x1cf/0x870 [ 32.795034] binder_poll+0x8c/0x390 [ 32.798623] ep_item_poll.isra.10+0xec/0x320 [ 32.802991] ep_insert+0x6a3/0x1b10 [ 32.806580] SyS_epoll_ctl+0x12e4/0x1ab0 [ 32.810604] do_fast_syscall_32+0x3ee/0xf9d [ 32.814888] entry_SYSENTER_compat+0x51/0x60 [ 32.819257] [ 32.820848] Freed by task 3086: [ 32.824090] save_stack+0x43/0xd0 [ 32.827505] kasan_slab_free+0x71/0xc0 [ 32.831353] kfree+0xca/0x250 [ 32.834421] binder_thread_dec_tmpref+0x27f/0x310 [ 32.839229] binder_thread_release+0x27d/0x540 [ 32.843773] binder_ioctl+0xc05/0x141a [ 32.847622] compat_SyS_ioctl+0x151/0x2a30 [ 32.851818] do_fast_syscall_32+0x3ee/0xf9d [ 32.856103] entry_SYSENTER_compat+0x51/0x60 [ 32.860470] [ 32.862064] The buggy address belongs to the object at ffff8801cd8e1340 [ 32.862064] which belongs to the cache kmalloc-512 of size 512 [ 32.874682] The buggy address is located 176 bytes inside of [ 32.874682] 512-byte region [ffff8801cd8e1340, ffff8801cd8e1540) [ 32.886516] The buggy address belongs to the page: [ 32.891414] page:000000005245354e count:1 mapcount:0 mapping:000000001b93048b index:0xffff8801cd8e1840 [ 32.900820] flags: 0x2fffc0000000100(slab) [ 32.905018] raw: 02fffc0000000100 ffff8801cd8e10c0 ffff8801cd8e1840 0000000100000005 [ 32.912859] raw: ffffea00073404e0 ffffea0007340920 ffff8801db000940 0000000000000000 [ 32.920701] page dumped because: kasan: bad access detected [ 32.926371] [ 32.927959] Memory state around the buggy address: [ 32.932849] ffff8801cd8e1280: 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 32.940171] ffff8801cd8e1300: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 32.947495] >ffff8801cd8e1380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.954822] ^ [ 32.961795] ffff8801cd8e1400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.969121] ffff8801cd8e1480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.976440] ================================================================== [ 32.983761] Disabling lock debugging due to kernel taint [ 32.989175] Kernel panic - not syncing: panic_on_warn set ... [ 32.989175] [ 32.996507] CPU: 1 PID: 3086 Comm: syzkaller236979 Tainted: G B 4.15.0-rc1+ #115 [ 33.005217] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.014532] Call Trace: [ 33.017086] dump_stack+0x194/0x257 [ 33.020678] ? arch_local_irq_restore+0x53/0x53 [ 33.025310] ? vprintk_default+0x28/0x30 [ 33.029333] ? vsnprintf+0x1ed/0x1900 [ 33.033099] ? __lock_acquire+0x4620/0x47f0 [ 33.037383] panic+0x1e4/0x41c [ 33.040540] ? refcount_error_report+0x214/0x214 [ 33.045262] ? add_taint+0x40/0x50 [ 33.048766] ? add_taint+0x1c/0x50 [ 33.052270] ? __lock_acquire+0x465e/0x47f0 [ 33.056555] kasan_end_report+0x50/0x50 [ 33.060492] kasan_report+0x144/0x340 [ 33.064257] __asan_report_load8_noabort+0x14/0x20 [ 33.069148] __lock_acquire+0x465e/0x47f0 [ 33.073259] ? __lock_acquire+0x6e9/0x47f0 [ 33.077459] ? update_cfs_rq_load_avg.part.70+0x2d0/0x2d0 [ 33.082967] ? print_usage_bug+0x3f0/0x3f0 [ 33.087174] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.092331] ? __lock_acquire+0x6e9/0x47f0 [ 33.096528] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.101681] ? update_cfs_rq_load_avg.part.70+0x2d0/0x2d0 [ 33.107510] ? _raw_spin_unlock_irqrestore+0xa6/0xba [ 33.112578] ? __lock_acquire+0x6e9/0x47f0 [ 33.116776] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 33.121927] ? lock_acquire+0x1d5/0x580 [ 33.125864] ? ep_free+0xf4/0x320 [ 33.129279] ? lock_release+0xda0/0xda0 [ 33.133218] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 33.139064] ? print_usage_bug+0x3f0/0x3f0 [ 33.143262] ? rcu_note_context_switch+0x710/0x710 [ 33.148154] ? __might_sleep+0x95/0x190 [ 33.152092] ? ep_free+0xf4/0x320 [ 33.155513] ? __mutex_lock+0x16f/0x1a80 [ 33.159536] ? ep_free+0xf4/0x320 [ 33.162954] ? print_usage_bug+0x3f0/0x3f0 [ 33.167153] ? ep_free+0xf4/0x320 [ 33.170569] ? print_usage_bug+0x3f0/0x3f0 [ 33.174771] lock_acquire+0x1d5/0x580 [ 33.178536] ? remove_wait_queue+0x81/0x350 [ 33.182820] ? __lock_acquire+0x6e9/0x47f0 [ 33.187017] ? lock_release+0xda0/0xda0 [ 33.190956] ? __lock_acquire+0x6e9/0x47f0 [ 33.195156] ? lock_acquire+0x1d5/0x580 [ 33.199093] ? ep_unregister_pollwait.isra.7+0x323/0x590 [ 33.204508] _raw_spin_lock_irqsave+0x96/0xc0 [ 33.208967] ? remove_wait_queue+0x81/0x350 [ 33.213252] remove_wait_queue+0x81/0x350 [ 33.217364] ? prepare_to_wait+0x4d0/0x4d0 [ 33.221563] ? rcutorture_record_progress+0x10/0x10 [ 33.226542] ? lock_release+0xda0/0xda0 [ 33.230478] ep_unregister_pollwait.isra.7+0x18c/0x590 [ 33.235718] ? __kernel_text_address+0xd/0x40 [ 33.240176] ? clear_tfile_check_list+0x370/0x370 [ 33.244984] ? check_noncircular+0x20/0x20 [ 33.249194] ? free_fs_struct+0x52/0x60 [ 33.253131] ? locks_remove_file+0x3fa/0x5a0 [ 33.257508] ep_free+0x13f/0x320 [ 33.260837] ? ep_remove+0x800/0x800 [ 33.264515] ? fsnotify_first_mark+0x2b0/0x2b0 [ 33.269058] ? ep_free+0x320/0x320 [ 33.272558] ep_eventpoll_release+0x44/0x60 [ 33.276845] __fput+0x333/0x7f0 [ 33.280089] ? fput+0x140/0x140 [ 33.283331] ? _raw_spin_unlock_irq+0x27/0x70 [ 33.287789] ____fput+0x15/0x20 [ 33.291032] task_work_run+0x199/0x270 [ 33.294882] ? task_work_cancel+0x210/0x210 [ 33.299166] ? _raw_spin_unlock+0x22/0x30 [ 33.303277] ? switch_task_namespaces+0x87/0xc0 [ 33.307910] do_exit+0x9bb/0x1ae0 [ 33.311327] ? trace_hardirqs_on+0xd/0x10 [ 33.315438] ? mm_update_next_owner+0x930/0x930 [ 33.320071] ? do_raw_spin_trylock+0x190/0x190 [ 33.324616] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 33.330463] ? _raw_spin_unlock+0x22/0x30 [ 33.334572] ? check_noncircular+0x20/0x20 [ 33.338771] ? __pmd_alloc+0x4e0/0x4e0 [ 33.342622] ? find_held_lock+0x39/0x1d0 [ 33.346646] ? find_held_lock+0x39/0x1d0 [ 33.350672] ? lock_downgrade+0x980/0x980 [ 33.354784] ? handle_mm_fault+0x410/0x8d0 [ 33.358981] ? down_read_trylock+0xdb/0x170 [ 33.363265] ? __do_page_fault+0x32d/0xc90 [ 33.367462] ? __handle_mm_fault+0x3e20/0x3e20 [ 33.372007] ? vmacache_find+0x5f/0x280 [ 33.375943] do_group_exit+0x149/0x400 [ 33.379794] ? __do_page_fault+0x3d6/0xc90 [ 33.383991] ? SyS_exit+0x30/0x30 [ 33.387407] ? do_fast_syscall_32+0x156/0xf9d [ 33.391868] ? do_group_exit+0x400/0x400 [ 33.395892] SyS_exit_group+0x1d/0x20 [ 33.399656] do_fast_syscall_32+0x3ee/0xf9d [ 33.403941] ? do_int80_syscall_32+0x9d0/0x9d0 [ 33.408486] ? kasan_check_read+0x11/0x20 [ 33.412600] ? syscall_return_slowpath+0x550/0x550 [ 33.417494] ? SyS_rt_sigaction+0x94/0x1b0 [ 33.421691] ? lockdep_sys_exit+0x47/0xf0 [ 33.425802] ? retint_user+0x18/0x18 [ 33.429480] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 33.434288] entry_SYSENTER_compat+0x51/0x60 [ 33.438658] RIP: 0023:0xf7f97c79 [ 33.441985] RSP: 002b:00000000ffcb51bc EFLAGS: 00000296 ORIG_RAX: 00000000000000fc [ 33.449654] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000080f0298 [ 33.456894] RDX: 0000000000000000 RSI: 00000000080d9b18 RDI: 00000000080f02a0 [ 33.464128] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 [ 33.471358] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 33.478592] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 33.486204] Dumping ftrace buffer: [ 33.489705] (ftrace buffer empty) [ 33.493378] Kernel Offset: disabled [ 33.496969] Rebooting in 86400 seconds..