[....] Starting enhanced syslogd: rsyslogd[ 9.912698] audit: type=1400 audit(1516390540.861:4): avc: denied { syslog } for pid=3160 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 '10.128.15.218' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 39.340913] ================================================================== [ 39.342129] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 39.343117] Read of size 8 at addr ffff8801c7c4b140 by task syzkaller098292/3333 [ 39.344290] [ 39.344562] CPU: 1 PID: 3333 Comm: syzkaller098292 Not tainted 4.9.77-g9c3804b #17 [ 39.345593] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 39.346835] ffff8801c215fab0 ffffffff81d941c9 ffffea00071f12c0 ffff8801c7c4b140 [ 39.348115] 0000000000000000 ffff8801c7c4b140 ffff8801c938a338 ffff8801c215fae8 [ 39.349374] ffffffff8153db93 ffff8801c7c4b140 0000000000000008 0000000000000000 [ 39.350674] Call Trace: [ 39.351146] [] dump_stack+0xc1/0x128 [ 39.351900] [] print_address_description+0x73/0x280 [ 39.352843] [] kasan_report+0x275/0x360 [ 39.353612] [] ? sg_remove_request+0x103/0x120 [ 39.354543] [] __asan_report_load8_noabort+0x14/0x20 [ 39.355520] [] sg_remove_request+0x103/0x120 [ 39.356324] [] sg_finish_rem_req+0x295/0x340 [ 39.357189] [] sg_read+0xa1c/0x1440 [ 39.357958] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 39.358901] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 39.359852] [] ? fasync_helper+0x37/0xb0 [ 39.360934] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 39.367124] [] __vfs_read+0x103/0x670 [ 39.372551] [] ? default_llseek+0x290/0x290 [ 39.378497] [] ? fsnotify+0x86/0xf30 [ 39.383839] [] ? fsnotify+0xf30/0xf30 [ 39.389265] [] ? avc_policy_seqno+0x9/0x20 [ 39.395140] [] ? selinux_file_permission+0x82/0x460 [ 39.401778] [] ? security_file_permission+0x89/0x1e0 [ 39.408501] [] ? rw_verify_area+0xe5/0x2b0 [ 39.414356] [] vfs_read+0x11e/0x380 [ 39.419602] [] SyS_read+0xd9/0x1b0 [ 39.424762] [] ? vfs_copy_file_range+0x740/0x740 [ 39.431146] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 39.437964] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 39.444518] [] entry_SYSCALL_64_fastpath+0x29/0xe8 [ 39.451086] [ 39.452688] Allocated by task 0: [ 39.456021] (stack is not available) [ 39.459698] [ 39.461305] Freed by task 0: [ 39.464289] (stack is not available) [ 39.467969] [ 39.469566] The buggy address belongs to the object at ffff8801c7c4b100 [ 39.469566] which belongs to the cache fasync_cache of size 96 [ 39.482192] The buggy address is located 64 bytes inside of [ 39.482192] 96-byte region [ffff8801c7c4b100, ffff8801c7c4b160) [ 39.493861] The buggy address belongs to the page: [ 39.498760] page:ffffea00071f12c0 count:1 mapcount:0 mapping: (null) index:0x0 [ 39.507004] flags: 0x8000000000000080(slab) [ 39.511292] page dumped because: kasan: bad access detected [ 39.516967] [ 39.518563] Memory state around the buggy address: [ 39.523460] ffff8801c7c4b000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 39.530787] ffff8801c7c4b080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 39.538114] >ffff8801c7c4b100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 39.545440] ^ [ 39.550859] ffff8801c7c4b180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 39.558187] ffff8801c7c4b200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 39.565512] ================================================================== [ 39.572837] Disabling lock debugging due to kernel taint [ 39.578476] Kernel panic - not syncing: panic_on_warn set ... [ 39.578476] [ 39.585822] CPU: 1 PID: 3333 Comm: syzkaller098292 Tainted: G B 4.9.77-g9c3804b #17 [ 39.594807] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 39.604140] ffff8801c215fa08 ffffffff81d941c9 ffffffff841970ff ffff8801c215fae0 [ 39.612175] 0000000000000000 ffff8801c7c4b140 ffff8801c938a338 ffff8801c215fad0 [ 39.620154] ffffffff8142f3c1 0000000041b58ab3 ffffffff8418ab70 ffffffff8142f205 [ 39.628583] Call Trace: [ 39.631145] [] dump_stack+0xc1/0x128 [ 39.636481] [] panic+0x1bc/0x3a8 [ 39.641468] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 39.649666] [] ? preempt_schedule+0x25/0x30 [ 39.655608] [] ? ___preempt_schedule+0x16/0x18 [ 39.661810] [] kasan_end_report+0x50/0x50 [ 39.667579] [] kasan_report+0x167/0x360 [ 39.673178] [] ? sg_remove_request+0x103/0x120 [ 39.679382] [] __asan_report_load8_noabort+0x14/0x20 [ 39.686104] [] sg_remove_request+0x103/0x120 [ 39.692133] [] sg_finish_rem_req+0x295/0x340 [ 39.698160] [] sg_read+0xa1c/0x1440 [ 39.703406] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 39.710042] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 39.717028] [] ? fasync_helper+0x37/0xb0 [ 39.722707] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 39.729355] [] __vfs_read+0x103/0x670 [ 39.734775] [] ? default_llseek+0x290/0x290 [ 39.740801] [] ? fsnotify+0x86/0xf30 [ 39.746143] [] ? fsnotify+0xf30/0xf30 [ 39.751564] [] ? avc_policy_seqno+0x9/0x20 [ 39.757431] [] ? selinux_file_permission+0x82/0x460 [ 39.764069] [] ? security_file_permission+0x89/0x1e0 [ 39.770798] [] ? rw_verify_area+0xe5/0x2b0 [ 39.776651] [] vfs_read+0x11e/0x380 [ 39.781984] [] SyS_read+0xd9/0x1b0 [ 39.787143] [] ? vfs_copy_file_range+0x740/0x740 [ 39.793520] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 39.800333] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 39.806893] [] entry_SYSCALL_64_fastpath+0x29/0xe8 [ 39.813834] Dumping ftrace buffer: [ 39.817342] (ftrace buffer empty) [ 39.821022] Kernel Offset: disabled [ 39.824621] Rebooting in 86400 seconds..