[....] Starting enhanced syslogd: rsyslogd[ 14.448105] audit: type=1400 audit(1517499148.274:4): avc: denied { syslog } for pid=3909 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 periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] 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 '10.128.0.61' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 26.023414] ================================================================== [ 26.030801] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 26.037877] Read of size 8 at addr ffff8801da2e0140 by task syzkaller151891/4064 [ 26.045386] [ 26.047001] CPU: 1 PID: 4064 Comm: syzkaller151891 Not tainted 4.9.79-g71f1469 #25 [ 26.054685] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.064023] ffff8801d4557ab0 ffffffff81d94829 ffffea000768b800 ffff8801da2e0140 [ 26.072011] 0000000000000000 ffff8801da2e0140 ffff8801d482a338 ffff8801d4557ae8 [ 26.079997] ffffffff8153e083 ffff8801da2e0140 0000000000000008 0000000000000000 [ 26.087995] Call Trace: [ 26.090562] [] dump_stack+0xc1/0x128 [ 26.095902] [] print_address_description+0x73/0x280 [ 26.102536] [] kasan_report+0x275/0x360 [ 26.108130] [] ? sg_remove_request+0x103/0x120 [ 26.114326] [] __asan_report_load8_noabort+0x14/0x20 [ 26.121049] [] sg_remove_request+0x103/0x120 [ 26.127076] [] sg_finish_rem_req+0x295/0x340 [ 26.133098] [] sg_read+0xa16/0x1440 [ 26.138342] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.144980] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 26.151959] [] ? fasync_helper+0x37/0xb0 [ 26.157634] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.164264] [] __vfs_read+0x103/0x670 [ 26.169682] [] ? default_llseek+0x290/0x290 [ 26.175626] [] ? fsnotify+0x86/0xf30 [ 26.180953] [] ? fsnotify+0xf30/0xf30 [ 26.186375] [] ? avc_policy_seqno+0x9/0x20 [ 26.192228] [] ? selinux_file_permission+0x82/0x460 [ 26.198867] [] ? security_file_permission+0x89/0x1e0 [ 26.205589] [] ? rw_verify_area+0xe5/0x2b0 [ 26.211440] [] vfs_read+0x11e/0x380 [ 26.216687] [] SyS_read+0xd9/0x1b0 [ 26.221855] [] ? vfs_copy_file_range+0x740/0x740 [ 26.228234] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 26.235041] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.241588] [] entry_SYSCALL_64_fastpath+0x29/0xe8 [ 26.248133] [ 26.249731] Allocated by task 0: [ 26.253066] (stack is not available) [ 26.256746] [ 26.258351] Freed by task 0: [ 26.261340] (stack is not available) [ 26.265016] [ 26.266612] The buggy address belongs to the object at ffff8801da2e0100 [ 26.266612] which belongs to the cache fasync_cache of size 96 [ 26.279235] The buggy address is located 64 bytes inside of [ 26.279235] 96-byte region [ffff8801da2e0100, ffff8801da2e0160) [ 26.290899] The buggy address belongs to the page: [ 26.295796] page:ffffea000768b800 count:1 mapcount:0 mapping: (null) index:0x0 [ 26.304020] flags: 0x8000000000000080(slab) [ 26.308305] page dumped because: kasan: bad access detected [ 26.313982] [ 26.315575] Memory state around the buggy address: [ 26.320471] ffff8801da2e0000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 26.327796] ffff8801da2e0080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.335120] >ffff8801da2e0100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.342451] ^ [ 26.347874] ffff8801da2e0180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.355206] ffff8801da2e0200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.362541] ================================================================== [ 26.369867] Disabling lock debugging due to kernel taint [ 26.375578] Kernel panic - not syncing: panic_on_warn set ... [ 26.375578] [ 26.382931] CPU: 1 PID: 4064 Comm: syzkaller151891 Tainted: G B 4.9.79-g71f1469 #25 [ 26.391833] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.401165] ffff8801d4557a08 ffffffff81d94829 ffffffff8419709f ffff8801d4557ae0 [ 26.409144] 0000000000000000 ffff8801da2e0140 ffff8801d482a338 ffff8801d4557ad0 [ 26.417115] ffffffff8142f531 0000000041b58ab3 ffffffff8418ab10 ffffffff8142f375 [ 26.425087] Call Trace: [ 26.427648] [] dump_stack+0xc1/0x128 [ 26.432980] [] panic+0x1bc/0x3a8 [ 26.437963] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 26.446165] [] ? preempt_schedule+0x25/0x30 [ 26.452104] [] ? ___preempt_schedule+0x16/0x18 [ 26.458304] [] kasan_end_report+0x50/0x50 [ 26.464080] [] kasan_report+0x167/0x360 [ 26.469678] [] ? sg_remove_request+0x103/0x120 [ 26.475878] [] __asan_report_load8_noabort+0x14/0x20 [ 26.482616] [] sg_remove_request+0x103/0x120 [ 26.488647] [] sg_finish_rem_req+0x295/0x340 [ 26.494672] [] sg_read+0xa16/0x1440 [ 26.499922] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.506557] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 26.513540] [] ? fasync_helper+0x37/0xb0 [ 26.519231] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.525865] [] __vfs_read+0x103/0x670 [ 26.531281] [] ? default_llseek+0x290/0x290 [ 26.537218] [] ? fsnotify+0x86/0xf30 [ 26.542548] [] ? fsnotify+0xf30/0xf30 [ 26.547965] [] ? avc_policy_seqno+0x9/0x20 [ 26.553814] [] ? selinux_file_permission+0x82/0x460 [ 26.560455] [] ? security_file_permission+0x89/0x1e0 [ 26.567178] [] ? rw_verify_area+0xe5/0x2b0 [ 26.573033] [] vfs_read+0x11e/0x380 [ 26.578276] [] SyS_read+0xd9/0x1b0 [ 26.583434] [] ? vfs_copy_file_range+0x740/0x740 [ 26.589812] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 26.596625] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.603171] [] entry_SYSCALL_64_fastpath+0x29/0xe8 [ 26.610152] Dumping ftrace buffer: [ 26.613663] (ftrace buffer empty) [ 26.617340] Kernel Offset: disabled [ 26.620936] Rebooting in 86400 seconds..