[....] Starting enhanced syslogd: rsyslogd[ 14.332916] audit: type=1400 audit(1515604443.837:4): avc: denied { syslog } for pid=3189 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 '10.128.0.19' (ECDSA) to the list of known hosts. executing program executing program syzkaller login: [ 41.321570] ================================================================== [ 41.328971] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 41.336048] Read of size 8 at addr ffff8801c9677240 by task syzkaller677808/3356 [ 41.343554] [ 41.345150] CPU: 1 PID: 3356 Comm: syzkaller677808 Not tainted 4.9.76-g9154940 #20 [ 41.352820] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.362139] ffff8801c8bd7a50 ffffffff81d93149 ffffea0007259dc0 ffff8801c9677240 [ 41.370090] 0000000000000000 ffff8801c9677240 ffff8801c6cc0238 ffff8801c8bd7a88 [ 41.378034] ffffffff8153cb43 ffff8801c9677240 0000000000000008 0000000000000000 [ 41.385980] Call Trace: [ 41.388536] [] dump_stack+0xc1/0x128 [ 41.393866] [] print_address_description+0x73/0x280 [ 41.400494] [] kasan_report+0x275/0x360 [ 41.406102] [] ? sg_remove_request+0x103/0x120 [ 41.412297] [] __asan_report_load8_noabort+0x14/0x20 [ 41.419022] [] sg_remove_request+0x103/0x120 [ 41.425043] [] sg_finish_rem_req+0x295/0x340 [ 41.431065] [] sg_read+0xa1c/0x1440 [ 41.436304] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 41.442934] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 41.449911] [] ? vma_set_page_prot+0x10f/0x180 [ 41.456105] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 41.462735] [] __vfs_read+0x103/0x670 [ 41.468150] [] ? default_llseek+0x290/0x290 [ 41.474092] [] ? fsnotify+0x86/0xf30 [ 41.479418] [] ? fsnotify+0xf30/0xf30 [ 41.484833] [] ? avc_policy_seqno+0x9/0x20 [ 41.490682] [] ? selinux_file_permission+0x82/0x460 [ 41.497322] [] ? security_file_permission+0x89/0x1e0 [ 41.504038] [] ? rw_verify_area+0xe5/0x2b0 [ 41.509886] [] vfs_read+0x11e/0x380 [ 41.515129] [] SyS_read+0xd9/0x1b0 [ 41.520283] [] ? vfs_copy_file_range+0x740/0x740 [ 41.526653] [] ? do_fast_syscall_32+0xcf/0x890 [ 41.532848] [] ? vfs_copy_file_range+0x740/0x740 [ 41.539217] [] do_fast_syscall_32+0x2f7/0x890 [ 41.545336] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 41.551979] [] entry_SYSENTER_compat+0x74/0x83 [ 41.558181] [ 41.559783] Allocated by task 0: [ 41.563125] (stack is not available) [ 41.566800] [ 41.568410] Freed by task 0: [ 41.571388] (stack is not available) [ 41.575062] [ 41.576658] The buggy address belongs to the object at ffff8801c9677200 [ 41.576658] which belongs to the cache fasync_cache of size 96 [ 41.589278] The buggy address is located 64 bytes inside of [ 41.589278] 96-byte region [ffff8801c9677200, ffff8801c9677260) [ 41.600947] The buggy address belongs to the page: [ 41.605851] page:ffffea0007259dc0 count:1 mapcount:0 mapping: (null) index:0x0 [ 41.614067] flags: 0x8000000000000080(slab) [ 41.618350] page dumped because: kasan: bad access detected [ 41.624021] [ 41.625612] Memory state around the buggy address: [ 41.630505] ffff8801c9677100: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 41.637827] ffff8801c9677180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 41.645148] >ffff8801c9677200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 41.652470] ^ [ 41.657882] ffff8801c9677280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 41.665210] ffff8801c9677300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc executing program [ 41.672535] ================================================================== [ 41.679855] Disabling lock debugging due to kernel taint [ 41.685754] Kernel panic - not syncing: panic_on_warn set ... [ 41.685754] [ 41.693100] CPU: 1 PID: 3356 Comm: syzkaller677808 Tainted: G B 4.9.76-g9154940 #20 [ 41.701987] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.711307] ffff8801c8bd79a8 ffffffff81d93149 ffffffff84195c17 ffff8801c8bd7a80 [ 41.720149] 0000000000000000 ffff8801c9677240 ffff8801c6cc0238 ffff8801c8bd7a70 [ 41.728098] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 41.736061] Call Trace: [ 41.738627] [] dump_stack+0xc1/0x128 [ 41.743966] [] panic+0x1bc/0x3a8 [ 41.748953] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 41.757149] [] ? preempt_schedule+0x25/0x30 [ 41.763086] [] ? ___preempt_schedule+0x16/0x18 [ 41.769283] [] kasan_end_report+0x50/0x50 [ 41.775048] [] kasan_report+0x167/0x360 [ 41.780650] [] ? sg_remove_request+0x103/0x120 [ 41.786847] [] __asan_report_load8_noabort+0x14/0x20 [ 41.793563] [] sg_remove_request+0x103/0x120 [ 41.799583] [] sg_finish_rem_req+0x295/0x340 [ 41.805605] [] sg_read+0xa1c/0x1440 [ 41.810847] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 41.817480] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 41.824463] [] ? vma_set_page_prot+0x10f/0x180 [ 41.830659] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 41.837295] [] __vfs_read+0x103/0x670 [ 41.842717] [] ? default_llseek+0x290/0x290 [ 41.848653] [] ? fsnotify+0x86/0xf30 [ 41.853981] [] ? fsnotify+0xf30/0xf30 [ 41.859406] [] ? avc_policy_seqno+0x9/0x20 [ 41.865255] [] ? selinux_file_permission+0x82/0x460 [ 41.871884] [] ? security_file_permission+0x89/0x1e0 [ 41.878603] [] ? rw_verify_area+0xe5/0x2b0 [ 41.884455] [] vfs_read+0x11e/0x380 [ 41.889694] [] SyS_read+0xd9/0x1b0 [ 41.894859] [] ? vfs_copy_file_range+0x740/0x740 [ 41.901235] [] ? do_fast_syscall_32+0xcf/0x890 [ 41.907430] [] ? vfs_copy_file_range+0x740/0x740 [ 41.913801] [] do_fast_syscall_32+0x2f7/0x890 [ 41.919911] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 41.926543] [] entry_SYSENTER_compat+0x74/0x83 [ 41.933086] Dumping ftrace buffer: [ 41.936599] (ftrace buffer empty) [ 41.940275] Kernel Offset: disabled [ 41.943875] Rebooting in 86400 seconds..