[....] Starting enhanced syslogd: rsyslogd[ 10.135507] audit: type=1400 audit(1515267359.865:4): avc: denied { syslog } for pid=3174 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 '10.128.15.203' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 31.550434] ================================================================== [ 31.551470] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 31.552402] Read of size 8 at addr ffff8801cbdc9140 by task syzkaller845312/3339 [ 31.553402] [ 31.553664] CPU: 1 PID: 3339 Comm: syzkaller845312 Not tainted 4.9.75-g06fe41f #16 [ 31.554709] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.555985] ffff8801c196fa50 ffffffff81d93049 ffffea00072f7240 ffff8801cbdc9140 [ 31.557143] 0000000000000000 ffff8801cbdc9140 ffff8801c8568238 ffff8801c196fa88 [ 31.558284] ffffffff8153ca53 ffff8801cbdc9140 0000000000000008 0000000000000000 [ 31.559429] Call Trace: [ 31.559789] [] dump_stack+0xc1/0x128 [ 31.560499] [] print_address_description+0x73/0x280 [ 31.561376] [] kasan_report+0x275/0x360 [ 31.562117] [] ? sg_remove_request+0x103/0x120 [ 31.562937] [] __asan_report_load8_noabort+0x14/0x20 [ 31.563822] [] sg_remove_request+0x103/0x120 [ 31.564669] [] sg_finish_rem_req+0x295/0x340 [ 31.565484] [] sg_read+0xa1c/0x1440 [ 31.566184] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 31.567063] [] ? __raw_spin_lock_init+0x1c/0x100 [ 31.567923] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 31.568820] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 31.569696] [] __vfs_read+0x103/0x670 [ 31.570450] [] ? default_llseek+0x290/0x290 [ 31.575953] [] ? fsnotify+0x86/0xf30 [ 31.581283] [] ? fsnotify+0xf30/0xf30 [ 31.586700] [] ? avc_policy_seqno+0x9/0x20 [ 31.592566] [] ? selinux_file_permission+0x82/0x460 [ 31.599200] [] ? security_file_permission+0x89/0x1e0 [ 31.605924] [] ? rw_verify_area+0xe5/0x2b0 [ 31.611773] [] vfs_read+0x11e/0x380 [ 31.617033] [] SyS_read+0xd9/0x1b0 [ 31.622197] [] ? vfs_copy_file_range+0x740/0x740 [ 31.628579] [] ? do_fast_syscall_32+0xcf/0x890 [ 31.634776] [] ? vfs_copy_file_range+0x740/0x740 [ 31.641155] [] do_fast_syscall_32+0x2f7/0x890 [ 31.647263] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 31.653894] [] entry_SYSENTER_compat+0x74/0x83 [ 31.660099] [ 31.661692] Allocated by task 0: [ 31.665018] (stack is not available) [ 31.668693] [ 31.670285] Freed by task 0: [ 31.673263] (stack is not available) [ 31.676938] [ 31.678532] The buggy address belongs to the object at ffff8801cbdc9100 [ 31.678532] which belongs to the cache fasync_cache of size 96 [ 31.691160] The buggy address is located 64 bytes inside of [ 31.691160] 96-byte region [ffff8801cbdc9100, ffff8801cbdc9160) [ 31.702824] The buggy address belongs to the page: [ 31.707721] page:ffffea00072f7240 count:1 mapcount:0 mapping: (null) index:0x0 [ 31.715938] flags: 0x8000000000000080(slab) [ 31.720223] page dumped because: kasan: bad access detected [ 31.725896] [ 31.727486] Memory state around the buggy address: [ 31.732378] ffff8801cbdc9000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 31.739709] ffff8801cbdc9080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.747037] >ffff8801cbdc9100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.754358] ^ [ 31.759772] ffff8801cbdc9180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.767097] ffff8801cbdc9200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.774421] ================================================================== [ 31.781753] Disabling lock debugging due to kernel taint [ 31.787240] Kernel panic - not syncing: panic_on_warn set ... [ 31.787240] [ 31.794584] CPU: 1 PID: 3339 Comm: syzkaller845312 Tainted: G B 4.9.75-g06fe41f #16 [ 31.803471] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.812800] ffff8801c196f9a8 ffffffff81d93049 ffffffff84195be7 ffff8801c196fa80 [ 31.820750] 0000000000000000 ffff8801cbdc9140 ffff8801c8568238 ffff8801c196fa70 [ 31.828705] ffffffff8142e281 0000000041b58ab3 ffffffff84189648 ffffffff8142e0c5 [ 31.836648] Call Trace: [ 31.839205] [] dump_stack+0xc1/0x128 [ 31.844533] [] panic+0x1bc/0x3a8 [ 31.849516] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 31.857713] [] ? preempt_schedule+0x25/0x30 [ 31.863652] [] ? ___preempt_schedule+0x16/0x18 [ 31.869852] [] kasan_end_report+0x50/0x50 [ 31.875617] [] kasan_report+0x167/0x360 [ 31.881208] [] ? sg_remove_request+0x103/0x120 [ 31.887405] [] __asan_report_load8_noabort+0x14/0x20 [ 31.894124] [] sg_remove_request+0x103/0x120 [ 31.900151] [] sg_finish_rem_req+0x295/0x340 [ 31.906173] [] sg_read+0xa1c/0x1440 [ 31.911422] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 31.918056] [] ? __raw_spin_lock_init+0x1c/0x100 [ 31.924427] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 31.931232] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 31.937864] [] __vfs_read+0x103/0x670 [ 31.943291] [] ? default_llseek+0x290/0x290 [ 31.949227] [] ? fsnotify+0x86/0xf30 [ 31.954555] [] ? fsnotify+0xf30/0xf30 [ 31.959971] [] ? avc_policy_seqno+0x9/0x20 [ 31.965818] [] ? selinux_file_permission+0x82/0x460 [ 31.972535] [] ? security_file_permission+0x89/0x1e0 [ 31.979265] [] ? rw_verify_area+0xe5/0x2b0 [ 31.985115] [] vfs_read+0x11e/0x380 [ 31.990362] [] SyS_read+0xd9/0x1b0 [ 31.995523] [] ? vfs_copy_file_range+0x740/0x740 [ 32.001896] [] ? do_fast_syscall_32+0xcf/0x890 [ 32.008097] [] ? vfs_copy_file_range+0x740/0x740 [ 32.014467] [] do_fast_syscall_32+0x2f7/0x890 [ 32.020580] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 32.027212] [] entry_SYSENTER_compat+0x74/0x83 [ 32.033788] Dumping ftrace buffer: [ 32.037292] (ftrace buffer empty) [ 32.040966] Kernel Offset: disabled [ 32.044557] Rebooting in 86400 seconds..