[....] Starting enhanced syslogd: rsyslogd[ 10.172382] audit: type=1400 audit(1515699044.034:4): avc: denied { syslog } for pid=3168 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 '10.128.15.232' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 18.770790] ================================================================== [ 18.771932] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 18.772887] Read of size 8 at addr ffff8801cadd5140 by task syzkaller194418/3316 [ 18.773870] [ 18.774101] CPU: 0 PID: 3316 Comm: syzkaller194418 Not tainted 4.9.76-g9154940 #20 [ 18.775130] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 18.776359] ffff8801c96dfa50 ffffffff81d93149 ffffea00072b7540 ffff8801cadd5140 [ 18.777490] 0000000000000000 ffff8801cadd5140 ffff8801c946c438 ffff8801c96dfa88 [ 18.778630] ffffffff8153cb43 ffff8801cadd5140 0000000000000008 0000000000000000 [ 18.779760] Call Trace: [ 18.780115] [] dump_stack+0xc1/0x128 [ 18.780845] [] print_address_description+0x73/0x280 [ 18.781730] [] kasan_report+0x275/0x360 [ 18.782494] [] ? sg_remove_request+0x103/0x120 [ 18.783340] [] __asan_report_load8_noabort+0x14/0x20 [ 18.784228] [] sg_remove_request+0x103/0x120 [ 18.785029] [] sg_finish_rem_req+0x295/0x340 [ 18.785837] [] sg_read+0xa1c/0x1440 [ 18.786534] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 18.787431] [] ? __raw_spin_lock_init+0x1c/0x100 [ 18.788274] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 18.789170] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 18.790046] [] __vfs_read+0x103/0x670 [ 18.790779] [] ? default_llseek+0x290/0x290 [ 18.796055] [] ? fsnotify+0x86/0xf30 [ 18.801385] [] ? fsnotify+0xf30/0xf30 [ 18.806810] [] ? avc_policy_seqno+0x9/0x20 [ 18.812670] [] ? selinux_file_permission+0x82/0x460 [ 18.819306] [] ? security_file_permission+0x89/0x1e0 [ 18.826555] [] ? rw_verify_area+0xe5/0x2b0 [ 18.832407] [] vfs_read+0x11e/0x380 [ 18.837646] [] SyS_read+0xd9/0x1b0 [ 18.843322] [] ? vfs_copy_file_range+0x740/0x740 [ 18.849693] [] ? do_fast_syscall_32+0xcf/0x890 [ 18.855894] [] ? vfs_copy_file_range+0x740/0x740 [ 18.862263] [] do_fast_syscall_32+0x2f7/0x890 [ 18.868378] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 18.875009] [] entry_SYSENTER_compat+0x74/0x83 [ 18.881207] [ 18.882802] Allocated by task 0: [ 18.886130] (stack is not available) [ 18.889803] [ 18.891397] Freed by task 0: [ 18.894377] (stack is not available) [ 18.898055] [ 18.899660] The buggy address belongs to the object at ffff8801cadd5100 [ 18.899660] which belongs to the cache fasync_cache of size 96 [ 18.912281] The buggy address is located 64 bytes inside of [ 18.912281] 96-byte region [ffff8801cadd5100, ffff8801cadd5160) [ 18.923944] The buggy address belongs to the page: [ 18.929190] page:ffffea00072b7540 count:1 mapcount:0 mapping: (null) index:0x0 [ 18.938272] flags: 0x8000000000000080(slab) [ 18.942554] page dumped because: kasan: bad access detected [ 18.948491] [ 18.950089] Memory state around the buggy address: [ 18.954995] ffff8801cadd5000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 18.962667] ffff8801cadd5080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 18.969990] >ffff8801cadd5100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 18.977314] ^ [ 18.982744] ffff8801cadd5180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 18.990068] ffff8801cadd5200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 18.998679] ================================================================== [ 19.006004] Disabling lock debugging due to kernel taint [ 19.011705] Kernel panic - not syncing: panic_on_warn set ... [ 19.011705] [ 19.019053] CPU: 0 PID: 3316 Comm: syzkaller194418 Tainted: G B 4.9.76-g9154940 #20 [ 19.027947] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 19.037278] ffff8801c96df9a8 ffffffff81d93149 ffffffff84195c17 ffff8801c96dfa80 [ 19.045311] 0000000000000000 ffff8801cadd5140 ffff8801c946c438 ffff8801c96dfa70 [ 19.053252] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 19.061201] Call Trace: [ 19.063755] [] dump_stack+0xc1/0x128 [ 19.069084] [] panic+0x1bc/0x3a8 [ 19.074065] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 19.082263] [] ? preempt_schedule+0x25/0x30 [ 19.088202] [] ? ___preempt_schedule+0x16/0x18 [ 19.094403] [] kasan_end_report+0x50/0x50 [ 19.100700] [] kasan_report+0x167/0x360 [ 19.106297] [] ? sg_remove_request+0x103/0x120 [ 19.112497] [] __asan_report_load8_noabort+0x14/0x20 [ 19.119212] [] sg_remove_request+0x103/0x120 [ 19.125241] [] sg_finish_rem_req+0x295/0x340 [ 19.131523] [] sg_read+0xa1c/0x1440 [ 19.136763] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.143394] [] ? __raw_spin_lock_init+0x1c/0x100 [ 19.149768] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 19.156570] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.163203] [] __vfs_read+0x103/0x670 [ 19.168620] [] ? default_llseek+0x290/0x290 [ 19.174558] [] ? fsnotify+0x86/0xf30 [ 19.179886] [] ? fsnotify+0xf30/0xf30 [ 19.185304] [] ? avc_policy_seqno+0x9/0x20 [ 19.191152] [] ? selinux_file_permission+0x82/0x460 [ 19.198043] [] ? security_file_permission+0x89/0x1e0 [ 19.204760] [] ? rw_verify_area+0xe5/0x2b0 [ 19.210609] [] vfs_read+0x11e/0x380 [ 19.216197] [] SyS_read+0xd9/0x1b0 [ 19.221523] [] ? vfs_copy_file_range+0x740/0x740 [ 19.227891] [] ? do_fast_syscall_32+0xcf/0x890 [ 19.234786] [] ? vfs_copy_file_range+0x740/0x740 [ 19.241154] [] do_fast_syscall_32+0x2f7/0x890 [ 19.247262] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 19.253894] [] entry_SYSENTER_compat+0x74/0x83 [ 19.261136] Dumping ftrace buffer: [ 19.264645] (ftrace buffer empty) [ 19.268319] Kernel Offset: disabled [ 19.271911] Rebooting in 86400 seconds..