[....] Starting enhanced syslogd: rsyslogd[ 10.607260] audit: type=1400 audit(1515419172.089:4): avc: denied { syslog } for pid=3170 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 periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.23' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 28.569589] ================================================================== [ 28.570732] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 28.571732] Read of size 8 at addr ffff8801c9a5f140 by task syzkaller680858/3327 [ 28.572745] [ 28.572975] CPU: 0 PID: 3327 Comm: syzkaller680858 Not tainted 4.9.75-g5f5e5d4 #7 [ 28.573987] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.575909] ffff8801c8d2fab0 ffffffff81d93049 ffffea00072697c0 ffff8801c9a5f140 [ 28.577071] 0000000000000000 ffff8801c9a5f140 ffff8801c2500238 ffff8801c8d2fae8 [ 28.578203] ffffffff8153ca53 ffff8801c9a5f140 0000000000000008 0000000000000000 [ 28.579333] Call Trace: [ 28.579712] [] dump_stack+0xc1/0x128 [ 28.580424] [] print_address_description+0x73/0x280 [ 28.581300] [] kasan_report+0x275/0x360 [ 28.582059] [] ? sg_remove_request+0x103/0x120 [ 28.582878] [] __asan_report_load8_noabort+0x14/0x20 [ 28.583763] [] sg_remove_request+0x103/0x120 [ 28.584560] [] sg_finish_rem_req+0x295/0x340 [ 28.585356] [] sg_read+0xa1c/0x1440 [ 28.586052] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 28.586959] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.587891] [] ? fasync_helper+0x37/0xb0 [ 28.588646] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 28.589521] [] __vfs_read+0x103/0x670 [ 28.592863] [] ? default_llseek+0x290/0x290 [ 28.598815] [] ? fsnotify+0x86/0xf30 [ 28.604145] [] ? fsnotify+0xf30/0xf30 [ 28.609571] [] ? avc_policy_seqno+0x9/0x20 [ 28.615423] [] ? selinux_file_permission+0x82/0x460 [ 28.622054] [] ? security_file_permission+0x89/0x1e0 [ 28.628773] [] ? rw_verify_area+0xe5/0x2b0 [ 28.634625] [] vfs_read+0x11e/0x380 [ 28.639869] [] SyS_read+0xd9/0x1b0 [ 28.645025] [] ? vfs_copy_file_range+0x740/0x740 [ 28.651406] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.658215] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 28.664765] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 28.671309] [ 28.672905] Allocated by task 0: [ 28.676233] (stack is not available) [ 28.679910] [ 28.681501] Freed by task 0: [ 28.684481] (stack is not available) [ 28.688156] [ 28.689749] The buggy address belongs to the object at ffff8801c9a5f100 [ 28.689749] which belongs to the cache fasync_cache of size 96 [ 28.702370] The buggy address is located 64 bytes inside of [ 28.702370] 96-byte region [ffff8801c9a5f100, ffff8801c9a5f160) [ 28.714034] The buggy address belongs to the page: [ 28.718930] page:ffffea00072697c0 count:1 mapcount:0 mapping: (null) index:0x0 [ 28.727147] flags: 0x8000000000000080(slab) [ 28.731433] page dumped because: kasan: bad access detected [ 28.737106] [ 28.738697] Memory state around the buggy address: [ 28.743590] ffff8801c9a5f000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 28.750928] ffff8801c9a5f080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 28.758252] >ffff8801c9a5f100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 28.765576] ^ [ 28.770990] ffff8801c9a5f180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 28.778316] ffff8801c9a5f200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 28.785640] ================================================================== [ 28.792962] Disabling lock debugging due to kernel taint [ 28.798645] Kernel panic - not syncing: panic_on_warn set ... [ 28.798645] [ 28.805982] CPU: 0 PID: 3327 Comm: syzkaller680858 Tainted: G B 4.9.75-g5f5e5d4 #7 [ 28.814792] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.824114] ffff8801c8d2fa08 ffffffff81d93049 ffffffff84195be7 ffff8801c8d2fae0 [ 28.832065] 0000000000000000 ffff8801c9a5f140 ffff8801c2500238 ffff8801c8d2fad0 [ 28.840014] ffffffff8142e281 0000000041b58ab3 ffffffff84189648 ffffffff8142e0c5 [ 28.847966] Call Trace: [ 28.850522] [] dump_stack+0xc1/0x128 [ 28.855852] [] panic+0x1bc/0x3a8 [ 28.860835] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 28.869042] [] ? preempt_schedule+0x25/0x30 [ 28.874977] [] ? ___preempt_schedule+0x16/0x18 [ 28.881175] [] kasan_end_report+0x50/0x50 [ 28.886936] [] kasan_report+0x167/0x360 [ 28.892527] [] ? sg_remove_request+0x103/0x120 [ 28.898724] [] __asan_report_load8_noabort+0x14/0x20 [ 28.905454] [] sg_remove_request+0x103/0x120 [ 28.911480] [] sg_finish_rem_req+0x295/0x340 [ 28.917501] [] sg_read+0xa1c/0x1440 [ 28.922749] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 28.929384] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.936363] [] ? fasync_helper+0x37/0xb0 [ 28.942039] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 28.948675] [] __vfs_read+0x103/0x670 [ 28.954092] [] ? default_llseek+0x290/0x290 [ 28.960029] [] ? fsnotify+0x86/0xf30 [ 28.965357] [] ? fsnotify+0xf30/0xf30 [ 28.970772] [] ? avc_policy_seqno+0x9/0x20 [ 28.976624] [] ? selinux_file_permission+0x82/0x460 [ 28.983257] [] ? security_file_permission+0x89/0x1e0 [ 28.989977] [] ? rw_verify_area+0xe5/0x2b0 [ 28.995827] [] vfs_read+0x11e/0x380 [ 29.001078] [] SyS_read+0xd9/0x1b0 [ 29.006244] [] ? vfs_copy_file_range+0x740/0x740 [ 29.012619] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 29.019426] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 29.025970] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 29.032884] Dumping ftrace buffer: [ 29.036394] (ftrace buffer empty) [ 29.040070] Kernel Offset: disabled [ 29.043665] Rebooting in 86400 seconds..