[....] Starting enhanced syslogd: rsyslogd[ 10.444652] audit: type=1400 audit(1515596480.590:4): avc: denied { syslog } for pid=3178 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 '10.128.0.28' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 38.360468] ================================================================== [ 38.361594] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 38.362694] Read of size 8 at addr ffff8801cd783140 by task syzkaller904347/3344 [ 38.363725] [ 38.363967] CPU: 0 PID: 3344 Comm: syzkaller904347 Not tainted 4.9.76-g9154940 #20 [ 38.365040] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 38.366370] ffff8801c7b47a50 ffffffff81d93149 ffffea000735e0c0 ffff8801cd783140 [ 38.367512] 0000000000000000 ffff8801cd783140 ffff8801c8862338 ffff8801c7b47a88 [ 38.368709] ffffffff8153cb43 ffff8801cd783140 0000000000000008 0000000000000000 [ 38.369838] Call Trace: [ 38.370215] [] dump_stack+0xc1/0x128 [ 38.370974] [] print_address_description+0x73/0x280 [ 38.371973] [] kasan_report+0x275/0x360 [ 38.373119] [] ? sg_remove_request+0x103/0x120 [ 38.374147] [] __asan_report_load8_noabort+0x14/0x20 [ 38.375115] [] sg_remove_request+0x103/0x120 [ 38.375967] [] sg_finish_rem_req+0x295/0x340 [ 38.376892] [] sg_read+0xa1c/0x1440 [ 38.377601] [] ? __raw_spin_lock_init+0x1c/0x100 [ 38.378508] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 38.379402] [] ? _raw_spin_unlock+0x2c/0x50 [ 38.380275] [] ? fasync_insert_entry+0x147/0x2e0 [ 38.384630] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 38.391264] [] __vfs_read+0x103/0x670 [ 38.396680] [] ? default_llseek+0x290/0x290 [ 38.402621] [] ? fsnotify+0x86/0xf30 [ 38.407951] [] ? fsnotify+0xf30/0xf30 [ 38.413369] [] ? avc_policy_seqno+0x9/0x20 [ 38.419219] [] ? selinux_file_permission+0x82/0x460 [ 38.425860] [] ? security_file_permission+0x89/0x1e0 [ 38.432595] [] ? rw_verify_area+0xe5/0x2b0 [ 38.438453] [] vfs_read+0x11e/0x380 [ 38.443697] [] SyS_read+0xd9/0x1b0 [ 38.448856] [] ? vfs_copy_file_range+0x740/0x740 [ 38.455240] [] ? compat_SyS_ioctl+0x8c/0x2050 [ 38.461369] [] ? do_fast_syscall_32+0xcf/0x890 [ 38.467578] [] ? vfs_copy_file_range+0x740/0x740 [ 38.473950] [] do_fast_syscall_32+0x2f7/0x890 [ 38.480064] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 38.486959] [] entry_SYSENTER_compat+0x74/0x83 [ 38.493154] [ 38.494749] Allocated by task 0: [ 38.498078] (stack is not available) [ 38.501754] [ 38.503354] Freed by task 0: [ 38.506336] (stack is not available) [ 38.510020] [ 38.511618] The buggy address belongs to the object at ffff8801cd783100 [ 38.511618] which belongs to the cache fasync_cache of size 96 [ 38.524242] The buggy address is located 64 bytes inside of [ 38.524242] 96-byte region [ffff8801cd783100, ffff8801cd783160) [ 38.535906] The buggy address belongs to the page: [ 38.540804] page:ffffea000735e0c0 count:1 mapcount:0 mapping: (null) index:0x0 [ 38.549029] flags: 0x8000000000000080(slab) [ 38.553320] page dumped because: kasan: bad access detected [ 38.559000] [ 38.560592] Memory state around the buggy address: [ 38.565495] ffff8801cd783000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 38.572837] ffff8801cd783080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 38.580163] >ffff8801cd783100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 38.587496] ^ [ 38.592911] ffff8801cd783180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 38.600246] ffff8801cd783200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 38.607570] ================================================================== [ 38.614901] Disabling lock debugging due to kernel taint [ 38.620528] Kernel panic - not syncing: panic_on_warn set ... [ 38.620528] [ 38.627874] CPU: 0 PID: 3344 Comm: syzkaller904347 Tainted: G B 4.9.76-g9154940 #20 [ 38.636784] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 38.646107] ffff8801c7b479a8 ffffffff81d93149 ffffffff84195c17 ffff8801c7b47a80 [ 38.654067] 0000000000000000 ffff8801cd783140 ffff8801c8862338 ffff8801c7b47a70 [ 38.662020] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 38.669969] Call Trace: [ 38.672527] [] dump_stack+0xc1/0x128 [ 38.677859] [] panic+0x1bc/0x3a8 [ 38.682851] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 38.691048] [] ? preempt_schedule+0x25/0x30 [ 38.696992] [] ? ___preempt_schedule+0x16/0x18 [ 38.703195] [] kasan_end_report+0x50/0x50 [ 38.708968] [] kasan_report+0x167/0x360 [ 38.714580] [] ? sg_remove_request+0x103/0x120 [ 38.720782] [] __asan_report_load8_noabort+0x14/0x20 [ 38.727502] [] sg_remove_request+0x103/0x120 [ 38.733535] [] sg_finish_rem_req+0x295/0x340 [ 38.739561] [] sg_read+0xa1c/0x1440 [ 38.744805] [] ? __raw_spin_lock_init+0x1c/0x100 [ 38.751176] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 38.757810] [] ? _raw_spin_unlock+0x2c/0x50 [ 38.763748] [] ? fasync_insert_entry+0x147/0x2e0 [ 38.770120] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 38.776766] [] __vfs_read+0x103/0x670 [ 38.782184] [] ? default_llseek+0x290/0x290 [ 38.788215] [] ? fsnotify+0x86/0xf30 [ 38.793557] [] ? fsnotify+0xf30/0xf30 [ 38.798974] [] ? avc_policy_seqno+0x9/0x20 [ 38.804825] [] ? selinux_file_permission+0x82/0x460 [ 38.811471] [] ? security_file_permission+0x89/0x1e0 [ 38.818192] [] ? rw_verify_area+0xe5/0x2b0 [ 38.824054] [] vfs_read+0x11e/0x380 [ 38.829311] [] SyS_read+0xd9/0x1b0 [ 38.834554] [] ? vfs_copy_file_range+0x740/0x740 [ 38.840924] [] ? compat_SyS_ioctl+0x8c/0x2050 [ 38.847040] [] ? do_fast_syscall_32+0xcf/0x890 [ 38.853239] [] ? vfs_copy_file_range+0x740/0x740 [ 38.859621] [] do_fast_syscall_32+0x2f7/0x890 [ 38.865733] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 38.872370] [] entry_SYSENTER_compat+0x74/0x83 [ 38.878995] Dumping ftrace buffer: [ 38.882507] (ftrace buffer empty) [ 38.886185] Kernel Offset: disabled [ 38.889778] Rebooting in 86400 seconds..