[....] Starting enhanced syslogd: rsyslogd[ 13.203023] audit: type=1400 audit(1515922218.203:4): avc: denied { syslog } for pid=3174 comm="rsyslogd" capability=34 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=capability2 permissive=1 [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.58' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 28.534456] audit: type=1400 audit(1515922233.533:5): avc: denied { block_suspend } for pid=3331 comm="syzkaller510982" capability=36 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=capability2 permissive=1 [ 28.560566] ================================================================== [ 28.567929] BUG: KASAN: use-after-free in __lock_acquire+0x2eff/0x3640 [ 28.574565] Read of size 8 at addr ffff8801c936f238 by task syzkaller510982/3331 [ 28.582066] [ 28.583678] CPU: 1 PID: 3331 Comm: syzkaller510982 Not tainted 4.9.76-g8e170a5 #21 [ 28.591351] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.600677] ffff8801c808f870 ffffffff81d93149 ffffea000724db80 ffff8801c936f238 [ 28.608654] 0000000000000000 ffff8801c936f238 ffff8801c936f238 ffff8801c808f8a8 [ 28.616621] ffffffff8153cb43 ffff8801c936f238 0000000000000008 0000000000000000 [ 28.624674] Call Trace: [ 28.627237] [] dump_stack+0xc1/0x128 [ 28.632572] [] print_address_description+0x73/0x280 [ 28.639212] [] kasan_report+0x275/0x360 [ 28.644806] [] ? __lock_acquire+0x2eff/0x3640 [ 28.650920] [] __asan_report_load8_noabort+0x14/0x20 [ 28.657652] [] __lock_acquire+0x2eff/0x3640 [ 28.663593] [] ? __lock_acquire+0x629/0x3640 [ 28.669631] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.677487] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.684470] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.691466] [] ? mark_held_locks+0xaf/0x100 [ 28.697504] [] ? mutex_lock_nested+0x5e3/0x870 [ 28.703705] [] lock_acquire+0x12e/0x410 [ 28.709315] [] ? remove_wait_queue+0x14/0x40 [ 28.715341] [] _raw_spin_lock_irqsave+0x4e/0x70 [ 28.721631] [] ? remove_wait_queue+0x14/0x40 [ 28.727657] [] remove_wait_queue+0x14/0x40 [ 28.733512] [] ep_unregister_pollwait.isra.6+0xaf/0x240 [ 28.740495] [] ? ep_unregister_pollwait.isra.6+0x12a/0x240 [ 28.747737] [] ? ep_free+0x1b0/0x1b0 [ 28.753068] [] ep_free+0x96/0x1b0 [ 28.758147] [] ? ep_free+0x1b0/0x1b0 [ 28.763496] [] ep_eventpoll_release+0x44/0x60 [ 28.769630] [] __fput+0x28c/0x6e0 [ 28.774705] [] ____fput+0x15/0x20 [ 28.779786] [] task_work_run+0x115/0x190 [ 28.785481] [] do_exit+0x7e7/0x2a40 [ 28.790729] [] ? __pmd_alloc+0x410/0x410 [ 28.796438] [] ? release_task+0x1240/0x1240 [ 28.802399] [] ? __do_page_fault+0x5ec/0xd40 [ 28.808444] [] ? up_read+0x1a/0x40 [ 28.813613] [] ? __do_page_fault+0x3bd/0xd40 [ 28.819642] [] do_group_exit+0x108/0x320 [ 28.825324] [] ? do_group_exit+0x320/0x320 [ 28.831187] [] SyS_exit_group+0x1d/0x20 [ 28.836781] [] do_fast_syscall_32+0x2f7/0x890 [ 28.842897] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 28.849534] [] entry_SYSENTER_compat+0x74/0x83 [ 28.855748] [ 28.857346] Allocated by task 3331: [ 28.860944] save_stack_trace+0x16/0x20 [ 28.864894] save_stack+0x43/0xd0 [ 28.868336] kasan_kmalloc+0xad/0xe0 [ 28.872019] kmem_cache_alloc_trace+0xfb/0x2a0 [ 28.876571] binder_get_thread+0x15d/0x750 [ 28.880771] binder_poll+0x4a/0x210 [ 28.884380] SyS_epoll_ctl+0x11d7/0x2190 [ 28.888409] do_fast_syscall_32+0x2f7/0x890 [ 28.892707] entry_SYSENTER_compat+0x74/0x83 [ 28.897091] [ 28.898693] Freed by task 3331: [ 28.901946] save_stack_trace+0x16/0x20 [ 28.905891] save_stack+0x43/0xd0 [ 28.909311] kasan_slab_free+0x72/0xc0 [ 28.913167] kfree+0x103/0x300 [ 28.916330] binder_thread_dec_tmpref+0x1cc/0x240 [ 28.921143] binder_thread_release+0x27d/0x540 [ 28.925693] binder_ioctl+0x9c0/0x11b0 [ 28.929552] compat_SyS_ioctl+0x15f/0x2050 [ 28.933766] do_fast_syscall_32+0x2f7/0x890 [ 28.938058] entry_SYSENTER_compat+0x74/0x83 [ 28.942434] [ 28.944032] The buggy address belongs to the object at ffff8801c936f180 [ 28.944032] which belongs to the cache kmalloc-512 of size 512 [ 28.956656] The buggy address is located 184 bytes inside of [ 28.956656] 512-byte region [ffff8801c936f180, ffff8801c936f380) [ 28.968499] The buggy address belongs to the page: [ 28.973408] page:ffffea000724db80 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 28.983577] flags: 0x8000000000004080(slab|head) [ 28.988301] page dumped because: kasan: bad access detected [ 28.993984] [ 28.995582] Memory state around the buggy address: [ 29.000479] ffff8801c936f100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 29.007812] ffff8801c936f180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 29.015147] >ffff8801c936f200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 29.022481] ^ [ 29.027641] ffff8801c936f280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 29.034970] ffff8801c936f300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 29.042300] ================================================================== [ 29.049627] Disabling lock debugging due to kernel taint [ 29.055051] Kernel panic - not syncing: panic_on_warn set ... [ 29.055051] [ 29.062383] CPU: 1 PID: 3331 Comm: syzkaller510982 Tainted: G B 4.9.76-g8e170a5 #21 [ 29.071286] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.080612] ffff8801c808f7c8 ffffffff81d93149 ffffffff84195c17 ffff8801c808f8a0 [ 29.088592] 0000000000000000 ffff8801c936f238 ffff8801c936f238 ffff8801c808f890 [ 29.096560] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 29.104526] Call Trace: [ 29.107087] [] dump_stack+0xc1/0x128 [ 29.112421] [] panic+0x1bc/0x3a8 [ 29.117408] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 29.125606] [] ? add_taint+0x40/0x50 [ 29.130944] [] kasan_end_report+0x50/0x50 [ 29.136718] [] kasan_report+0x167/0x360 [ 29.142313] [] ? __lock_acquire+0x2eff/0x3640 [ 29.148428] [] __asan_report_load8_noabort+0x14/0x20 [ 29.155152] [] __lock_acquire+0x2eff/0x3640 [ 29.161098] [] ? __lock_acquire+0x629/0x3640 [ 29.167124] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 29.174194] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 29.181179] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 29.188162] [] ? mark_held_locks+0xaf/0x100 [ 29.194103] [] ? mutex_lock_nested+0x5e3/0x870 [ 29.201261] [] lock_acquire+0x12e/0x410 [ 29.206856] [] ? remove_wait_queue+0x14/0x40 [ 29.212882] [] _raw_spin_lock_irqsave+0x4e/0x70 [ 29.219170] [] ? remove_wait_queue+0x14/0x40 [ 29.225196] [] remove_wait_queue+0x14/0x40 [ 29.231053] [] ep_unregister_pollwait.isra.6+0xaf/0x240 [ 29.238035] [] ? ep_unregister_pollwait.isra.6+0x12a/0x240 [ 29.245282] [] ? ep_free+0x1b0/0x1b0 [ 29.250627] [] ep_free+0x96/0x1b0 [ 29.255698] [] ? ep_free+0x1b0/0x1b0 [ 29.261041] [] ep_eventpoll_release+0x44/0x60 [ 29.267158] [] __fput+0x28c/0x6e0 [ 29.272229] [] ____fput+0x15/0x20 [ 29.277302] [] task_work_run+0x115/0x190 [ 29.282982] [] do_exit+0x7e7/0x2a40 [ 29.288226] [] ? __pmd_alloc+0x410/0x410 [ 29.293907] [] ? release_task+0x1240/0x1240 [ 29.299850] [] ? __do_page_fault+0x5ec/0xd40 [ 29.305878] [] ? up_read+0x1a/0x40 [ 29.311045] [] ? __do_page_fault+0x3bd/0xd40 [ 29.317086] [] do_group_exit+0x108/0x320 [ 29.322767] [] ? do_group_exit+0x320/0x320 [ 29.328630] [] SyS_exit_group+0x1d/0x20 [ 29.334231] [] do_fast_syscall_32+0x2f7/0x890 [ 29.340359] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.346993] [] entry_SYSENTER_compat+0x74/0x83 [ 29.353578] Dumping ftrace buffer: [ 29.357086] (ftrace buffer empty) [ 29.360766] Kernel Offset: disabled [ 29.364371] Rebooting in 86400 seconds..