[....] Starting enhanced syslogd: rsyslogd[ 12.161683] audit: type=1400 audit(1516105814.942:4): avc: denied { syslog } for pid=3176 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[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?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 '10.128.0.13' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 46.355214] ================================================================== [ 46.362668] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 46.369753] Read of size 8 at addr ffff8801cbc6f140 by task syzkaller315605/3348 [ 46.377510] [ 46.379111] CPU: 1 PID: 3348 Comm: syzkaller315605 Not tainted 4.9.76-g8dec074 #23 [ 46.386791] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.396118] ffff8801c81d7a50 ffffffff81d93169 ffffea00072f1bc0 ffff8801cbc6f140 [ 46.404078] 0000000000000000 ffff8801cbc6f140 ffff8801ca4f2338 ffff8801c81d7a88 [ 46.412022] ffffffff8153cb43 ffff8801cbc6f140 0000000000000008 0000000000000000 [ 46.420000] Call Trace: [ 46.422561] [] dump_stack+0xc1/0x128 [ 46.427894] [] print_address_description+0x73/0x280 [ 46.434526] [] kasan_report+0x275/0x360 [ 46.440117] [] ? sg_remove_request+0x103/0x120 [ 46.446315] [] __asan_report_load8_noabort+0x14/0x20 [ 46.453034] [] sg_remove_request+0x103/0x120 [ 46.459060] [] sg_finish_rem_req+0x295/0x340 [ 46.465085] [] sg_read+0xa1c/0x1440 [ 46.470326] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 46.476959] [] ? __raw_spin_lock_init+0x1c/0x100 [ 46.483331] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 46.490137] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 46.496770] [] __vfs_read+0x103/0x670 [ 46.502202] [] ? default_llseek+0x290/0x290 [ 46.508140] [] ? fsnotify+0x86/0xf30 [ 46.513469] [] ? fsnotify+0xf30/0xf30 [ 46.518888] [] ? avc_policy_seqno+0x9/0x20 [ 46.524748] [] ? selinux_file_permission+0x82/0x460 [ 46.531380] [] ? security_file_permission+0x89/0x1e0 [ 46.538099] [] ? rw_verify_area+0xe5/0x2b0 [ 46.543958] [] vfs_read+0x11e/0x380 [ 46.549202] [] SyS_read+0xd9/0x1b0 [ 46.554357] [] ? vfs_copy_file_range+0x740/0x740 [ 46.560738] [] ? do_fast_syscall_32+0xcf/0x890 [ 46.566935] [] ? vfs_copy_file_range+0x740/0x740 [ 46.573306] [] do_fast_syscall_32+0x2f7/0x890 [ 46.579416] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 46.586056] [] entry_SYSENTER_compat+0x74/0x83 [ 46.592252] [ 46.593847] Allocated by task 0: [ 46.597174] (stack is not available) [ 46.600848] [ 46.602442] Freed by task 0: [ 46.605423] (stack is not available) [ 46.609099] [ 46.610694] The buggy address belongs to the object at ffff8801cbc6f100 [ 46.610694] which belongs to the cache fasync_cache of size 96 [ 46.623315] The buggy address is located 64 bytes inside of [ 46.623315] 96-byte region [ffff8801cbc6f100, ffff8801cbc6f160) [ 46.634978] The buggy address belongs to the page: [ 46.639874] page:ffffea00072f1bc0 count:1 mapcount:0 mapping: (null) index:0x0 [ 46.648102] flags: 0x8000000000000080(slab) [ 46.652387] page dumped because: kasan: bad access detected [ 46.658059] [ 46.659650] Memory state around the buggy address: [ 46.664547] ffff8801cbc6f000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 46.671880] ffff8801cbc6f080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 46.679208] >ffff8801cbc6f100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 46.686535] ^ [ 46.691968] ffff8801cbc6f180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 46.699294] ffff8801cbc6f200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 46.706619] ================================================================== [ 46.713946] Disabling lock debugging due to kernel taint [ 46.719612] Kernel panic - not syncing: panic_on_warn set ... [ 46.719612] [ 46.726966] CPU: 1 PID: 3348 Comm: syzkaller315605 Tainted: G B 4.9.76-g8dec074 #23 [ 46.735854] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.745199] ffff8801c81d79a8 ffffffff81d93169 ffffffff84195c2f ffff8801c81d7a80 [ 46.753162] 0000000000000000 ffff8801cbc6f140 ffff8801ca4f2338 ffff8801c81d7a70 [ 46.761130] ffffffff8142e371 0000000041b58ab3 ffffffff84189690 ffffffff8142e1b5 [ 46.769088] Call Trace: [ 46.771655] [] dump_stack+0xc1/0x128 [ 46.776986] [] panic+0x1bc/0x3a8 [ 46.781969] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 46.790168] [] ? preempt_schedule+0x25/0x30 [ 46.796108] [] ? ___preempt_schedule+0x16/0x18 [ 46.802310] [] kasan_end_report+0x50/0x50 [ 46.808089] [] kasan_report+0x167/0x360 [ 46.813703] [] ? sg_remove_request+0x103/0x120 [ 46.819909] [] __asan_report_load8_noabort+0x14/0x20 [ 46.826626] [] sg_remove_request+0x103/0x120 [ 46.832650] [] sg_finish_rem_req+0x295/0x340 [ 46.838684] [] sg_read+0xa1c/0x1440 [ 46.843939] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 46.850674] [] ? __raw_spin_lock_init+0x1c/0x100 [ 46.857051] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 46.863859] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 46.870494] [] __vfs_read+0x103/0x670 [ 46.875910] [] ? default_llseek+0x290/0x290 [ 46.881847] [] ? fsnotify+0x86/0xf30 [ 46.887185] [] ? fsnotify+0xf30/0xf30 [ 46.892603] [] ? avc_policy_seqno+0x9/0x20 [ 46.898455] [] ? selinux_file_permission+0x82/0x460 [ 46.905095] [] ? security_file_permission+0x89/0x1e0 [ 46.911817] [] ? rw_verify_area+0xe5/0x2b0 [ 46.917768] [] vfs_read+0x11e/0x380 [ 46.923018] [] SyS_read+0xd9/0x1b0 [ 46.928174] [] ? vfs_copy_file_range+0x740/0x740 [ 46.934546] [] ? do_fast_syscall_32+0xcf/0x890 [ 46.940743] [] ? vfs_copy_file_range+0x740/0x740 [ 46.947115] [] do_fast_syscall_32+0x2f7/0x890 [ 46.953226] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 46.959869] [] entry_SYSENTER_compat+0x74/0x83 [ 46.966124] Dumping ftrace buffer: [ 46.969633] (ftrace buffer empty) [ 46.973311] Kernel Offset: disabled [ 46.976909] Rebooting in 86400 seconds..