[....] Starting enhanced syslogd: rsyslogd[ 13.834772] audit: type=1400 audit(1515621595.602:4): 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[ 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 '10.128.0.63' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 24.991906] ================================================================== [ 24.999328] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 25.006409] Read of size 8 at addr ffff8801cbfeb140 by task syzkaller813001/3330 [ 25.013913] [ 25.015513] CPU: 1 PID: 3330 Comm: syzkaller813001 Not tainted 4.9.76-g9154940 #20 [ 25.023189] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.032518] ffff8801c86a7a50 ffffffff81d93149 ffffea00072ffac0 ffff8801cbfeb140 [ 25.040480] 0000000000000000 ffff8801cbfeb140 ffff8801c9282338 ffff8801c86a7a88 [ 25.048432] ffffffff8153cb43 ffff8801cbfeb140 0000000000000008 0000000000000000 [ 25.056388] Call Trace: [ 25.058952] [] dump_stack+0xc1/0x128 [ 25.064296] [] print_address_description+0x73/0x280 [ 25.070952] [] kasan_report+0x275/0x360 [ 25.076552] [] ? sg_remove_request+0x103/0x120 [ 25.082755] [] __asan_report_load8_noabort+0x14/0x20 [ 25.089474] [] sg_remove_request+0x103/0x120 [ 25.095497] [] sg_finish_rem_req+0x295/0x340 [ 25.101524] [] sg_read+0xa1c/0x1440 [ 25.106796] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.113444] [] ? __raw_spin_lock_init+0x1c/0x100 [ 25.119835] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 25.126646] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.133293] [] __vfs_read+0x103/0x670 [ 25.138714] [] ? default_llseek+0x290/0x290 [ 25.144654] [] ? fsnotify+0x86/0xf30 [ 25.150023] [] ? fsnotify+0xf30/0xf30 [ 25.155456] [] ? avc_policy_seqno+0x9/0x20 [ 25.161310] [] ? selinux_file_permission+0x82/0x460 [ 25.167957] [] ? security_file_permission+0x89/0x1e0 [ 25.174677] [] ? rw_verify_area+0xe5/0x2b0 [ 25.180528] [] vfs_read+0x11e/0x380 [ 25.185773] [] SyS_read+0xd9/0x1b0 [ 25.190933] [] ? vfs_copy_file_range+0x740/0x740 [ 25.197309] [] ? do_fast_syscall_32+0xcf/0x890 [ 25.203507] [] ? vfs_copy_file_range+0x740/0x740 [ 25.209890] [] do_fast_syscall_32+0x2f7/0x890 [ 25.216007] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.222643] [] entry_SYSENTER_compat+0x74/0x83 [ 25.228841] [ 25.230436] Allocated by task 0: [ 25.233778] (stack is not available) [ 25.237456] [ 25.239051] Freed by task 0: [ 25.242031] (stack is not available) [ 25.245707] [ 25.247301] The buggy address belongs to the object at ffff8801cbfeb100 [ 25.247301] which belongs to the cache fasync_cache of size 96 [ 25.259925] The buggy address is located 64 bytes inside of [ 25.259925] 96-byte region [ffff8801cbfeb100, ffff8801cbfeb160) [ 25.271592] The buggy address belongs to the page: [ 25.276492] page:ffffea00072ffac0 count:1 mapcount:0 mapping: (null) index:0x0 [ 25.284715] flags: 0x8000000000000080(slab) [ 25.289006] page dumped because: kasan: bad access detected [ 25.294676] [ 25.296269] Memory state around the buggy address: [ 25.301653] ffff8801cbfeb000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 25.308979] ffff8801cbfeb080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.316321] >ffff8801cbfeb100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.323648] ^ [ 25.329074] ffff8801cbfeb180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.336408] ffff8801cbfeb200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.343733] ================================================================== [ 25.351071] Disabling lock debugging due to kernel taint [ 25.356598] Kernel panic - not syncing: panic_on_warn set ... [ 25.356598] [ 25.363951] CPU: 1 PID: 3330 Comm: syzkaller813001 Tainted: G B 4.9.76-g9154940 #20 [ 25.372845] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.382172] ffff8801c86a79a8 ffffffff81d93149 ffffffff84195c17 ffff8801c86a7a80 [ 25.390222] 0000000000000000 ffff8801cbfeb140 ffff8801c9282338 ffff8801c86a7a70 [ 25.398177] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 25.406141] Call Trace: [ 25.408716] [] dump_stack+0xc1/0x128 [ 25.414050] [] panic+0x1bc/0x3a8 [ 25.419036] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 25.427246] [] ? preempt_schedule+0x25/0x30 [ 25.433186] [] ? ___preempt_schedule+0x16/0x18 [ 25.439391] [] kasan_end_report+0x50/0x50 [ 25.445154] [] kasan_report+0x167/0x360 [ 25.450750] [] ? sg_remove_request+0x103/0x120 [ 25.456963] [] __asan_report_load8_noabort+0x14/0x20 [ 25.463682] [] sg_remove_request+0x103/0x120 [ 25.469708] [] sg_finish_rem_req+0x295/0x340 [ 25.475731] [] sg_read+0xa1c/0x1440 [ 25.480982] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.487625] [] ? __raw_spin_lock_init+0x1c/0x100 [ 25.494013] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 25.500822] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.507470] [] __vfs_read+0x103/0x670 [ 25.512889] [] ? default_llseek+0x290/0x290 [ 25.518830] [] ? fsnotify+0x86/0xf30 [ 25.524159] [] ? fsnotify+0xf30/0xf30 [ 25.529578] [] ? avc_policy_seqno+0x9/0x20 [ 25.535430] [] ? selinux_file_permission+0x82/0x460 [ 25.542073] [] ? security_file_permission+0x89/0x1e0 [ 25.548805] [] ? rw_verify_area+0xe5/0x2b0 [ 25.554659] [] vfs_read+0x11e/0x380 [ 25.559906] [] SyS_read+0xd9/0x1b0 [ 25.565065] [] ? vfs_copy_file_range+0x740/0x740 [ 25.571439] [] ? do_fast_syscall_32+0xcf/0x890 [ 25.577650] [] ? vfs_copy_file_range+0x740/0x740 [ 25.584024] [] do_fast_syscall_32+0x2f7/0x890 [ 25.590139] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.596775] [] entry_SYSENTER_compat+0x74/0x83 [ 25.603049] Dumping ftrace buffer: [ 25.606566] (ftrace buffer empty) [ 25.610245] Kernel Offset: disabled [ 25.613838] Rebooting in 86400 seconds..