[....] Starting enhanced syslogd: rsyslogd[ 11.069742] audit: type=1400 audit(1515266675.741:4): avc: denied { syslog } for pid=3180 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 '10.128.0.14' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 21.172217] ================================================================== [ 21.173387] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 21.174356] Read of size 8 at addr ffff8801c966d140 by task syzkaller651341/3329 [ 21.175340] [ 21.175589] CPU: 0 PID: 3329 Comm: syzkaller651341 Not tainted 4.9.75-g06fe41f #16 [ 21.176615] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 21.177901] ffff8801c95e7a50 ffffffff81d93049 ffffea0007259b40 ffff8801c966d140 [ 21.179055] 0000000000000000 ffff8801c966d140 ffff8801ca3e4438 ffff8801c95e7a88 [ 21.180186] ffffffff8153ca53 ffff8801c966d140 0000000000000008 0000000000000000 [ 21.181315] Call Trace: [ 21.181674] [] dump_stack+0xc1/0x128 [ 21.182402] [] print_address_description+0x73/0x280 [ 21.183278] [] kasan_report+0x275/0x360 [ 21.184078] [] ? sg_remove_request+0x103/0x120 [ 21.184919] [] __asan_report_load8_noabort+0x14/0x20 [ 21.185805] [] sg_remove_request+0x103/0x120 [ 21.186604] [] sg_finish_rem_req+0x295/0x340 [ 21.187432] [] sg_read+0xa1c/0x1440 [ 21.188129] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.189006] [] ? __raw_spin_lock_init+0x1c/0x100 [ 21.189850] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 21.190750] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.191685] [] __vfs_read+0x103/0x670 [ 21.192404] [] ? default_llseek+0x290/0x290 [ 21.198342] [] ? fsnotify+0x86/0xf30 [ 21.203672] [] ? fsnotify+0xf30/0xf30 [ 21.209089] [] ? avc_policy_seqno+0x9/0x20 [ 21.214941] [] ? selinux_file_permission+0x82/0x460 [ 21.221574] [] ? security_file_permission+0x89/0x1e0 [ 21.228295] [] ? rw_verify_area+0xe5/0x2b0 [ 21.234145] [] vfs_read+0x11e/0x380 [ 21.239387] [] SyS_read+0xd9/0x1b0 [ 21.244543] [] ? vfs_copy_file_range+0x740/0x740 [ 21.250913] [] ? do_fast_syscall_32+0xcf/0x890 [ 21.257107] [] ? vfs_copy_file_range+0x740/0x740 [ 21.263478] [] do_fast_syscall_32+0x2f7/0x890 [ 21.269588] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 21.276223] [] entry_SYSENTER_compat+0x74/0x83 [ 21.282417] [ 21.284012] Allocated by task 0: [ 21.287338] (stack is not available) [ 21.291014] [ 21.292607] Freed by task 0: [ 21.295587] (stack is not available) [ 21.299265] [ 21.300857] The buggy address belongs to the object at ffff8801c966d100 [ 21.300857] which belongs to the cache fasync_cache of size 96 [ 21.313480] The buggy address is located 64 bytes inside of [ 21.313480] 96-byte region [ffff8801c966d100, ffff8801c966d160) [ 21.325144] The buggy address belongs to the page: [ 21.330040] page:ffffea0007259b40 count:1 mapcount:0 mapping: (null) index:0x0 [ 21.338272] flags: 0x8000000000000080(slab) [ 21.342556] page dumped because: kasan: bad access detected [ 21.348230] [ 21.349822] Memory state around the buggy address: [ 21.354715] ffff8801c966d000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 21.362038] ffff8801c966d080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.369362] >ffff8801c966d100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.376694] ^ [ 21.382119] ffff8801c966d180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.389455] ffff8801c966d200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.396777] ================================================================== [ 21.404099] Disabling lock debugging due to kernel taint [ 21.409734] Kernel panic - not syncing: panic_on_warn set ... [ 21.409734] [ 21.417081] CPU: 0 PID: 3329 Comm: syzkaller651341 Tainted: G B 4.9.75-g06fe41f #16 [ 21.425972] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 21.435296] ffff8801c95e79a8 ffffffff81d93049 ffffffff84195be7 ffff8801c95e7a80 [ 21.443241] 0000000000000000 ffff8801c966d140 ffff8801ca3e4438 ffff8801c95e7a70 [ 21.451201] ffffffff8142e281 0000000041b58ab3 ffffffff84189648 ffffffff8142e0c5 [ 21.459151] Call Trace: [ 21.461710] [] dump_stack+0xc1/0x128 [ 21.467038] [] panic+0x1bc/0x3a8 [ 21.472023] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 21.480217] [] ? preempt_schedule+0x25/0x30 [ 21.486165] [] ? ___preempt_schedule+0x16/0x18 [ 21.492364] [] kasan_end_report+0x50/0x50 [ 21.498127] [] kasan_report+0x167/0x360 [ 21.503718] [] ? sg_remove_request+0x103/0x120 [ 21.509917] [] __asan_report_load8_noabort+0x14/0x20 [ 21.516637] [] sg_remove_request+0x103/0x120 [ 21.522663] [] sg_finish_rem_req+0x295/0x340 [ 21.528688] [] sg_read+0xa1c/0x1440 [ 21.533933] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.540565] [] ? __raw_spin_lock_init+0x1c/0x100 [ 21.546941] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 21.553748] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.560398] [] __vfs_read+0x103/0x670 [ 21.565814] [] ? default_llseek+0x290/0x290 [ 21.571752] [] ? fsnotify+0x86/0xf30 [ 21.577080] [] ? fsnotify+0xf30/0xf30 [ 21.582499] [] ? avc_policy_seqno+0x9/0x20 [ 21.588360] [] ? selinux_file_permission+0x82/0x460 [ 21.594992] [] ? security_file_permission+0x89/0x1e0 [ 21.601739] [] ? rw_verify_area+0xe5/0x2b0 [ 21.607592] [] vfs_read+0x11e/0x380 [ 21.612834] [] SyS_read+0xd9/0x1b0 [ 21.617987] [] ? vfs_copy_file_range+0x740/0x740 [ 21.624355] [] ? do_fast_syscall_32+0xcf/0x890 [ 21.630550] [] ? vfs_copy_file_range+0x740/0x740 [ 21.636916] [] do_fast_syscall_32+0x2f7/0x890 [ 21.643024] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 21.649655] [] entry_SYSENTER_compat+0x74/0x83 [ 21.656236] Dumping ftrace buffer: [ 21.659739] (ftrace buffer empty) [ 21.663414] Kernel Offset: disabled [ 21.667007] Rebooting in 86400 seconds..