[....] Starting enhanced syslogd: rsyslogd[ 10.366215] audit: type=1400 audit(1515440127.435:4): avc: denied { syslog } for pid=3169 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 '10.128.0.62' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 39.937220] ================================================================== [ 39.938282] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 39.939213] Read of size 8 at addr ffff8801cd6c2140 by task syzkaller420184/3335 [ 39.940232] [ 39.940462] CPU: 0 PID: 3335 Comm: syzkaller420184 Not tainted 4.9.75-gb54d99a #18 [ 39.941496] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 39.942747] ffff8801c8297940 ffffffff81d93049 ffffea000735b080 ffff8801cd6c2140 [ 39.943880] 0000000000000000 ffff8801cd6c2140 ffff8801c9bcc438 ffff8801c8297978 [ 39.945012] ffffffff8153ca53 ffff8801cd6c2140 0000000000000008 0000000000000000 [ 39.946135] Call Trace: [ 39.946494] [] dump_stack+0xc1/0x128 [ 39.947218] [] print_address_description+0x73/0x280 [ 39.948092] [] kasan_report+0x275/0x360 [ 39.948910] [] ? sg_remove_request+0x103/0x120 [ 39.949730] [] __asan_report_load8_noabort+0x14/0x20 [ 39.950614] [] sg_remove_request+0x103/0x120 [ 39.951409] [] sg_finish_rem_req+0x295/0x340 [ 39.952205] [] sg_read+0xa1c/0x1440 [ 39.952903] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 39.953780] [] ? fsnotify+0xf30/0xf30 [ 39.954515] [] ? avc_policy_seqno+0x9/0x20 [ 39.955294] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 39.956214] [] ? security_file_permission+0x89/0x1e0 [ 39.957100] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 39.959251] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 39.965881] [] compat_do_readv_writev+0x522/0x760 [ 39.972335] [] ? do_pwritev+0x1a0/0x1a0 [ 39.977925] [] ? _raw_spin_unlock+0x2c/0x50 [ 39.983861] [] ? fasync_helper+0x7a/0xb0 [ 39.989536] [] ? __pmd_alloc+0x410/0x410 [ 39.995208] [] compat_readv+0xe3/0x150 [ 40.000711] [] do_compat_readv+0xf4/0x1d0 [ 40.006474] [] ? compat_readv+0x150/0x150 [ 40.012237] [] compat_SyS_readv+0x26/0x30 [ 40.017997] [] ? SyS_pwritev2+0x80/0x80 [ 40.023588] [] do_fast_syscall_32+0x2f7/0x890 [ 40.029695] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 40.036322] [] entry_SYSENTER_compat+0x74/0x83 [ 40.042514] [ 40.044106] Allocated by task 0: [ 40.047434] (stack is not available) [ 40.051108] [ 40.052697] Freed by task 0: [ 40.055676] (stack is not available) [ 40.059349] [ 40.060942] The buggy address belongs to the object at ffff8801cd6c2100 [ 40.060942] which belongs to the cache fasync_cache of size 96 [ 40.073559] The buggy address is located 64 bytes inside of [ 40.073559] 96-byte region [ffff8801cd6c2100, ffff8801cd6c2160) [ 40.085223] The buggy address belongs to the page: [ 40.090114] page:ffffea000735b080 count:1 mapcount:0 mapping: (null) index:0x0 [ 40.098335] flags: 0x8000000000000080(slab) [ 40.102617] page dumped because: kasan: bad access detected [ 40.108287] [ 40.109878] Memory state around the buggy address: [ 40.114771] ffff8801cd6c2000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 40.122093] ffff8801cd6c2080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 40.129416] >ffff8801cd6c2100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 40.136740] ^ [ 40.142153] ffff8801cd6c2180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 40.149476] ffff8801cd6c2200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 40.156799] ================================================================== [ 40.164121] Disabling lock debugging due to kernel taint [ 40.169687] Kernel panic - not syncing: panic_on_warn set ... [ 40.169687] [ 40.177024] CPU: 0 PID: 3335 Comm: syzkaller420184 Tainted: G B 4.9.75-gb54d99a #18 [ 40.185912] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 40.195232] ffff8801c8297898 ffffffff81d93049 ffffffff84195be7 ffff8801c8297970 [ 40.203176] 0000000000000000 ffff8801cd6c2140 ffff8801c9bcc438 ffff8801c8297960 [ 40.211127] ffffffff8142e281 0000000041b58ab3 ffffffff84189648 ffffffff8142e0c5 [ 40.219094] Call Trace: [ 40.221645] [] dump_stack+0xc1/0x128 [ 40.226977] [] panic+0x1bc/0x3a8 [ 40.231958] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 40.240151] [] ? preempt_schedule+0x25/0x30 [ 40.246087] [] ? ___preempt_schedule+0x16/0x18 [ 40.252285] [] kasan_end_report+0x50/0x50 [ 40.258046] [] kasan_report+0x167/0x360 [ 40.263633] [] ? sg_remove_request+0x103/0x120 [ 40.269828] [] __asan_report_load8_noabort+0x14/0x20 [ 40.276544] [] sg_remove_request+0x103/0x120 [ 40.282572] [] sg_finish_rem_req+0x295/0x340 [ 40.288593] [] sg_read+0xa1c/0x1440 [ 40.293833] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 40.300463] [] ? fsnotify+0xf30/0xf30 [ 40.305877] [] ? avc_policy_seqno+0x9/0x20 [ 40.311722] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 40.318698] [] ? security_file_permission+0x89/0x1e0 [ 40.326107] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 40.333255] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 40.339882] [] compat_do_readv_writev+0x522/0x760 [ 40.346338] [] ? do_pwritev+0x1a0/0x1a0 [ 40.351924] [] ? _raw_spin_unlock+0x2c/0x50 [ 40.357857] [] ? fasync_helper+0x7a/0xb0 [ 40.363529] [] ? __pmd_alloc+0x410/0x410 [ 40.369200] [] compat_readv+0xe3/0x150 [ 40.374699] [] do_compat_readv+0xf4/0x1d0 [ 40.380459] [] ? compat_readv+0x150/0x150 [ 40.386218] [] compat_SyS_readv+0x26/0x30 [ 40.391979] [] ? SyS_pwritev2+0x80/0x80 [ 40.397566] [] do_fast_syscall_32+0x2f7/0x890 [ 40.403674] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 40.410302] [] entry_SYSENTER_compat+0x74/0x83 [ 40.416532] Dumping ftrace buffer: [ 40.420035] (ftrace buffer empty) [ 40.423710] Kernel Offset: disabled [ 40.427300] Rebooting in 86400 seconds..