[....] Starting enhanced syslogd: rsyslogd[ 12.620804] audit: type=1400 audit(1515701260.140:4): avc: denied { syslog } for pid=3172 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 '10.128.15.246' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 19.804974] ================================================================== [ 19.812363] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 19.819429] Read of size 8 at addr ffff8801c8fef140 by task syzkaller168107/3326 [ 19.826924] [ 19.828530] CPU: 0 PID: 3326 Comm: syzkaller168107 Not tainted 4.9.76-g9154940 #10 [ 19.836199] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 19.845520] ffff8801c920fab0 ffffffff81d93149 ffffea000723fbc0 ffff8801c8fef140 [ 19.853476] 0000000000000000 ffff8801c8fef140 ffff8801caf48238 ffff8801c920fae8 [ 19.861432] ffffffff8153cb43 ffff8801c8fef140 0000000000000008 0000000000000000 [ 19.869379] Call Trace: [ 19.871939] [] dump_stack+0xc1/0x128 [ 19.877280] [] print_address_description+0x73/0x280 [ 19.883911] [] kasan_report+0x275/0x360 [ 19.889503] [] ? sg_remove_request+0x103/0x120 [ 19.895700] [] __asan_report_load8_noabort+0x14/0x20 [ 19.902418] [] sg_remove_request+0x103/0x120 [ 19.908441] [] sg_finish_rem_req+0x295/0x340 [ 19.914463] [] sg_read+0xa1c/0x1440 [ 19.919713] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.926349] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 19.933328] [] ? fasync_helper+0x37/0xb0 [ 19.939022] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.945752] [] __vfs_read+0x103/0x670 [ 19.951166] [] ? default_llseek+0x290/0x290 [ 19.957101] [] ? fsnotify+0x86/0xf30 [ 19.962429] [] ? fsnotify+0xf30/0xf30 [ 19.967846] [] ? avc_policy_seqno+0x9/0x20 [ 19.973695] [] ? selinux_file_permission+0x82/0x460 [ 19.980326] [] ? security_file_permission+0x89/0x1e0 [ 19.987056] [] ? rw_verify_area+0xe5/0x2b0 [ 19.992907] [] vfs_read+0x11e/0x380 [ 19.998148] [] SyS_read+0xd9/0x1b0 [ 20.003304] [] ? vfs_copy_file_range+0x740/0x740 [ 20.009676] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 20.016482] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 20.023040] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 20.029584] [ 20.031180] Allocated by task 0: [ 20.034506] (stack is not available) [ 20.038192] [ 20.039784] Freed by task 0: [ 20.042771] (stack is not available) [ 20.046445] [ 20.048051] The buggy address belongs to the object at ffff8801c8fef100 [ 20.048051] which belongs to the cache fasync_cache of size 96 [ 20.060671] The buggy address is located 64 bytes inside of [ 20.060671] 96-byte region [ffff8801c8fef100, ffff8801c8fef160) [ 20.072346] The buggy address belongs to the page: [ 20.077243] page:ffffea000723fbc0 count:1 mapcount:0 mapping: (null) index:0x0 [ 20.085464] flags: 0x8000000000000080(slab) [ 20.089749] page dumped because: kasan: bad access detected [ 20.095421] [ 20.097014] Memory state around the buggy address: [ 20.101909] ffff8801c8fef000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 20.109234] ffff8801c8fef080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 20.116555] >ffff8801c8fef100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 20.123887] ^ [ 20.129307] ffff8801c8fef180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 20.136629] ffff8801c8fef200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 20.143959] ================================================================== [ 20.151307] Disabling lock debugging due to kernel taint [ 20.157021] Kernel panic - not syncing: panic_on_warn set ... [ 20.157021] [ 20.164365] CPU: 0 PID: 3326 Comm: syzkaller168107 Tainted: G B 4.9.76-g9154940 #10 [ 20.173267] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 20.182590] ffff8801c920fa08 ffffffff81d93149 ffffffff84195c17 ffff8801c920fae0 [ 20.190547] 0000000000000000 ffff8801c8fef140 ffff8801caf48238 ffff8801c920fad0 [ 20.198493] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 20.206440] Call Trace: [ 20.208998] [] dump_stack+0xc1/0x128 [ 20.214329] [] panic+0x1bc/0x3a8 [ 20.219312] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 20.227507] [] ? preempt_schedule+0x25/0x30 [ 20.233448] [] ? ___preempt_schedule+0x16/0x18 [ 20.239646] [] kasan_end_report+0x50/0x50 [ 20.245408] [] kasan_report+0x167/0x360 [ 20.250998] [] ? sg_remove_request+0x103/0x120 [ 20.257204] [] __asan_report_load8_noabort+0x14/0x20 [ 20.263928] [] sg_remove_request+0x103/0x120 [ 20.269951] [] sg_finish_rem_req+0x295/0x340 [ 20.275974] [] sg_read+0xa1c/0x1440 [ 20.281223] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 20.287859] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 20.294843] [] ? fasync_helper+0x37/0xb0 [ 20.300521] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 20.307162] [] __vfs_read+0x103/0x670 [ 20.312577] [] ? default_llseek+0x290/0x290 [ 20.318524] [] ? fsnotify+0x86/0xf30 [ 20.323851] [] ? fsnotify+0xf30/0xf30 [ 20.329278] [] ? avc_policy_seqno+0x9/0x20 [ 20.335129] [] ? selinux_file_permission+0x82/0x460 [ 20.341759] [] ? security_file_permission+0x89/0x1e0 [ 20.348477] [] ? rw_verify_area+0xe5/0x2b0 [ 20.354326] [] vfs_read+0x11e/0x380 [ 20.359566] [] SyS_read+0xd9/0x1b0 [ 20.364729] [] ? vfs_copy_file_range+0x740/0x740 [ 20.371111] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 20.377915] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 20.384461] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 20.391471] Dumping ftrace buffer: [ 20.394977] (ftrace buffer empty) [ 20.398661] Kernel Offset: disabled [ 20.402262] Rebooting in 86400 seconds..