[....] Starting enhanced syslogd: rsyslogd[ 10.729934] audit: type=1400 audit(1515933111.740:4): avc: denied { syslog } for pid=3175 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 OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.15.247' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 19.170194] ================================================================== [ 19.171305] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 19.172241] Read of size 8 at addr ffff8801cc33a140 by task syzkaller080434/3323 [ 19.173226] [ 19.173480] CPU: 1 PID: 3323 Comm: syzkaller080434 Not tainted 4.9.76-gf0f6293 #12 [ 19.174513] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 19.175747] ffff8801c8427ab0 ffffffff81d93149 ffffea000730ce80 ffff8801cc33a140 [ 19.176944] 0000000000000000 ffff8801cc33a140 ffff8801c7f58238 ffff8801c8427ae8 [ 19.178180] ffffffff8153cb43 ffff8801cc33a140 0000000000000008 0000000000000000 [ 19.179329] Call Trace: [ 19.179691] [] dump_stack+0xc1/0x128 [ 19.180417] [] print_address_description+0x73/0x280 [ 19.181316] [] kasan_report+0x275/0x360 [ 19.182082] [] ? sg_remove_request+0x103/0x120 [ 19.182945] [] __asan_report_load8_noabort+0x14/0x20 [ 19.183918] [] sg_remove_request+0x103/0x120 [ 19.184731] [] sg_finish_rem_req+0x295/0x340 [ 19.185534] [] sg_read+0xa1c/0x1440 [ 19.186263] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.187147] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 19.188070] [] ? fasync_helper+0x37/0xb0 [ 19.188826] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.189716] [] __vfs_read+0x103/0x670 [ 19.191382] [] ? default_llseek+0x290/0x290 [ 19.197322] [] ? fsnotify+0x86/0xf30 [ 19.202661] [] ? fsnotify+0xf30/0xf30 [ 19.208082] [] ? avc_policy_seqno+0x9/0x20 [ 19.213953] [] ? selinux_file_permission+0x82/0x460 [ 19.220592] [] ? security_file_permission+0x89/0x1e0 [ 19.227319] [] ? rw_verify_area+0xe5/0x2b0 [ 19.233174] [] vfs_read+0x11e/0x380 [ 19.238421] [] SyS_read+0xd9/0x1b0 [ 19.243584] [] ? vfs_copy_file_range+0x740/0x740 [ 19.249967] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 19.256778] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 19.263329] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 19.269876] [ 19.271474] Allocated by task 0: [ 19.274806] (stack is not available) [ 19.278494] [ 19.280090] Freed by task 0: [ 19.283073] (stack is not available) [ 19.286754] [ 19.288351] The buggy address belongs to the object at ffff8801cc33a100 [ 19.288351] which belongs to the cache fasync_cache of size 96 [ 19.300982] The buggy address is located 64 bytes inside of [ 19.300982] 96-byte region [ffff8801cc33a100, ffff8801cc33a160) [ 19.312655] The buggy address belongs to the page: [ 19.317560] page:ffffea000730ce80 count:1 mapcount:0 mapping: (null) index:0x0 [ 19.325793] flags: 0x8000000000000080(slab) [ 19.330079] page dumped because: kasan: bad access detected [ 19.335754] [ 19.337348] Memory state around the buggy address: [ 19.342246] ffff8801cc33a000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 19.349578] ffff8801cc33a080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.356914] >ffff8801cc33a100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.364251] ^ [ 19.369669] ffff8801cc33a180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.377000] ffff8801cc33a200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.384330] ================================================================== [ 19.391661] Disabling lock debugging due to kernel taint [ 19.397308] Kernel panic - not syncing: panic_on_warn set ... [ 19.397308] [ 19.404665] CPU: 1 PID: 3323 Comm: syzkaller080434 Tainted: G B 4.9.76-gf0f6293 #12 [ 19.413563] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 19.422897] ffff8801c8427a08 ffffffff81d93149 ffffffff84195c17 ffff8801c8427ae0 [ 19.430868] 0000000000000000 ffff8801cc33a140 ffff8801c7f58238 ffff8801c8427ad0 [ 19.438862] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 19.446858] Call Trace: [ 19.449419] [] dump_stack+0xc1/0x128 [ 19.454765] [] panic+0x1bc/0x3a8 [ 19.459777] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 19.467982] [] ? preempt_schedule+0x25/0x30 [ 19.473928] [] ? ___preempt_schedule+0x16/0x18 [ 19.480146] [] kasan_end_report+0x50/0x50 [ 19.485914] [] kasan_report+0x167/0x360 [ 19.491508] [] ? sg_remove_request+0x103/0x120 [ 19.497710] [] __asan_report_load8_noabort+0x14/0x20 [ 19.504434] [] sg_remove_request+0x103/0x120 [ 19.510468] [] sg_finish_rem_req+0x295/0x340 [ 19.516498] [] sg_read+0xa1c/0x1440 [ 19.521752] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.528400] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 19.535383] [] ? fasync_helper+0x37/0xb0 [ 19.541062] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.547707] [] __vfs_read+0x103/0x670 [ 19.553127] [] ? default_llseek+0x290/0x290 [ 19.559066] [] ? fsnotify+0x86/0xf30 [ 19.564397] [] ? fsnotify+0xf30/0xf30 [ 19.569819] [] ? avc_policy_seqno+0x9/0x20 [ 19.575673] [] ? selinux_file_permission+0x82/0x460 [ 19.582308] [] ? security_file_permission+0x89/0x1e0 [ 19.589032] [] ? rw_verify_area+0xe5/0x2b0 [ 19.594901] [] vfs_read+0x11e/0x380 [ 19.600148] [] SyS_read+0xd9/0x1b0 [ 19.605312] [] ? vfs_copy_file_range+0x740/0x740 [ 19.611690] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 19.618501] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 19.625050] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 19.632060] Dumping ftrace buffer: [ 19.635570] (ftrace buffer empty) [ 19.639252] Kernel Offset: disabled [ 19.642847] Rebooting in 86400 seconds..