[....] Starting enhanced syslogd: rsyslogd[ 14.246670] audit: type=1400 audit(1517252863.024:4): avc: denied { syslog } for pid=3903 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 periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Starting mcstransd: [....] 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 '10.128.0.16' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 27.095902] ================================================================== [ 27.103292] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 27.110371] Read of size 8 at addr ffff8801c88f0140 by task syzkaller874679/4059 [ 27.117885] [ 27.119488] CPU: 1 PID: 4059 Comm: syzkaller874679 Not tainted 4.9.78-g7be1985 #24 [ 27.127161] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.136488] ffff8801d380f9b0 ffffffff81d94409 ffffea0007223c00 ffff8801c88f0140 [ 27.144455] 0000000000000000 ffff8801c88f0140 ffff8801d3888238 ffff8801d380f9e8 [ 27.152427] ffffffff8153dc73 ffff8801c88f0140 0000000000000008 0000000000000000 [ 27.160393] Call Trace: [ 27.162957] [] dump_stack+0xc1/0x128 [ 27.168294] [] print_address_description+0x73/0x280 [ 27.174929] [] kasan_report+0x275/0x360 [ 27.180534] [] ? sg_remove_request+0x103/0x120 [ 27.186750] [] __asan_report_load8_noabort+0x14/0x20 [ 27.193479] [] sg_remove_request+0x103/0x120 [ 27.199509] [] sg_finish_rem_req+0x295/0x340 [ 27.205537] [] sg_read+0xa16/0x1440 [ 27.210791] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 27.217432] [] ? fsnotify+0xf30/0xf30 [ 27.222861] [] ? avc_policy_seqno+0x9/0x20 [ 27.228721] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 27.235721] [] ? security_file_permission+0x89/0x1e0 [ 27.242462] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 27.249111] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 27.255764] [] do_readv_writev+0x520/0x750 [ 27.261640] [] ? vfs_write+0x530/0x530 [ 27.267157] [] ? _raw_spin_unlock+0x2c/0x50 [ 27.273110] [] ? __pmd_alloc+0x410/0x410 [ 27.278803] [] ? __do_page_fault+0x5ec/0xd40 [ 27.284840] [] vfs_readv+0x84/0xc0 [ 27.290003] [] do_readv+0xe6/0x250 [ 27.295190] [] ? vfs_readv+0xc0/0xc0 [ 27.300530] [] ? entry_SYSCALL_64_fastpath+0x5/0xe8 [ 27.307178] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 27.313994] [] SyS_readv+0x27/0x30 [ 27.319168] [] entry_SYSCALL_64_fastpath+0x29/0xe8 [ 27.325715] [ 27.327327] Allocated by task 0: [ 27.330667] (stack is not available) [ 27.334350] [ 27.335947] Freed by task 0: [ 27.338930] (stack is not available) [ 27.342614] [ 27.344214] The buggy address belongs to the object at ffff8801c88f0100 [ 27.344214] which belongs to the cache fasync_cache of size 96 [ 27.356854] The buggy address is located 64 bytes inside of [ 27.356854] 96-byte region [ffff8801c88f0100, ffff8801c88f0160) [ 27.368527] The buggy address belongs to the page: [ 27.373432] page:ffffea0007223c00 count:1 mapcount:0 mapping: (null) index:0x0 [ 27.381658] flags: 0x8000000000000080(slab) [ 27.385948] page dumped because: kasan: bad access detected [ 27.391625] [ 27.393217] Memory state around the buggy address: [ 27.398115] ffff8801c88f0000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 27.405446] ffff8801c88f0080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.412780] >ffff8801c88f0100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.420111] ^ [ 27.425537] ffff8801c88f0180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.432870] ffff8801c88f0200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.440212] ================================================================== [ 27.447543] Disabling lock debugging due to kernel taint [ 27.453251] Kernel panic - not syncing: panic_on_warn set ... [ 27.453251] [ 27.460596] CPU: 1 PID: 4059 Comm: syzkaller874679 Tainted: G B 4.9.78-g7be1985 #24 [ 27.469487] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.478824] ffff8801d380f908 ffffffff81d94409 ffffffff841971bf ffff8801d380f9e0 [ 27.486813] 0000000000000000 ffff8801c88f0140 ffff8801d3888238 ffff8801d380f9d0 [ 27.494779] ffffffff8142f4a1 0000000041b58ab3 ffffffff8418ac30 ffffffff8142f2e5 [ 27.502756] Call Trace: [ 27.505316] [] dump_stack+0xc1/0x128 [ 27.510659] [] panic+0x1bc/0x3a8 [ 27.515648] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 27.523861] [] ? preempt_schedule+0x25/0x30 [ 27.529805] [] ? ___preempt_schedule+0x16/0x18 [ 27.536012] [] kasan_end_report+0x50/0x50 [ 27.541786] [] kasan_report+0x167/0x360 [ 27.547384] [] ? sg_remove_request+0x103/0x120 [ 27.553590] [] __asan_report_load8_noabort+0x14/0x20 [ 27.560321] [] sg_remove_request+0x103/0x120 [ 27.566361] [] sg_finish_rem_req+0x295/0x340 [ 27.572390] [] sg_read+0xa16/0x1440 [ 27.577641] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 27.584281] [] ? fsnotify+0xf30/0xf30 [ 27.589709] [] ? avc_policy_seqno+0x9/0x20 [ 27.595570] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 27.602559] [] ? security_file_permission+0x89/0x1e0 [ 27.609286] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 27.615927] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 27.622565] [] do_readv_writev+0x520/0x750 [ 27.628420] [] ? vfs_write+0x530/0x530 [ 27.633931] [] ? _raw_spin_unlock+0x2c/0x50 [ 27.639874] [] ? __pmd_alloc+0x410/0x410 [ 27.645573] [] ? __do_page_fault+0x5ec/0xd40 [ 27.651605] [] vfs_readv+0x84/0xc0 [ 27.656771] [] do_readv+0xe6/0x250 [ 27.661933] [] ? vfs_readv+0xc0/0xc0 [ 27.667268] [] ? entry_SYSCALL_64_fastpath+0x5/0xe8 [ 27.673908] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 27.680721] [] SyS_readv+0x27/0x30 [ 27.685893] [] entry_SYSCALL_64_fastpath+0x29/0xe8 [ 27.692920] Dumping ftrace buffer: [ 27.696432] (ftrace buffer empty) [ 27.700112] Kernel Offset: disabled [ 27.703711] Rebooting in 86400 seconds..