[....] Starting enhanced syslogd: rsyslogd[ 11.380134] audit: type=1400 audit(1515264438.443:4): avc: denied { syslog } for pid=3176 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 '10.128.0.23' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 20.763597] ================================================================== [ 20.770996] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 20.778063] Read of size 8 at addr ffff8801c8213140 by task syzkaller973178/3325 [ 20.785558] [ 20.787156] CPU: 0 PID: 3325 Comm: syzkaller973178 Not tainted 4.9.75-g06fe41f #16 [ 20.794829] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 20.804152] ffff8801c8287a50 ffffffff81d93049 ffffea00072084c0 ffff8801c8213140 [ 20.812104] 0000000000000000 ffff8801c8213140 ffff8801c82e8238 ffff8801c8287a88 [ 20.820052] ffffffff8153ca53 ffff8801c8213140 0000000000000008 0000000000000000 [ 20.828014] Call Trace: [ 20.830569] [] dump_stack+0xc1/0x128 [ 20.835902] [] print_address_description+0x73/0x280 [ 20.842533] [] kasan_report+0x275/0x360 [ 20.848135] [] ? sg_remove_request+0x103/0x120 [ 20.854342] [] __asan_report_load8_noabort+0x14/0x20 [ 20.861058] [] sg_remove_request+0x103/0x120 [ 20.867080] [] sg_finish_rem_req+0x295/0x340 [ 20.873099] [] sg_read+0xa1c/0x1440 [ 20.878341] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 20.884971] [] ? __raw_spin_lock_init+0x1c/0x100 [ 20.891341] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 20.898145] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 20.904774] [] __vfs_read+0x103/0x670 [ 20.910188] [] ? default_llseek+0x290/0x290 [ 20.916127] [] ? fsnotify+0x86/0xf30 [ 20.921453] [] ? fsnotify+0xf30/0xf30 [ 20.926869] [] ? avc_policy_seqno+0x9/0x20 [ 20.932719] [] ? selinux_file_permission+0x82/0x460 [ 20.939784] [] ? security_file_permission+0x89/0x1e0 [ 20.946501] [] ? rw_verify_area+0xe5/0x2b0 [ 20.952349] [] vfs_read+0x11e/0x380 [ 20.957591] [] SyS_read+0xd9/0x1b0 [ 20.962759] [] ? vfs_copy_file_range+0x740/0x740 [ 20.969129] [] ? do_fast_syscall_32+0xcf/0x890 [ 20.975333] [] ? vfs_copy_file_range+0x740/0x740 [ 20.981704] [] do_fast_syscall_32+0x2f7/0x890 [ 20.987814] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 20.994445] [] entry_SYSENTER_compat+0x74/0x83 [ 21.000988] [ 21.002582] Allocated by task 0: [ 21.005911] (stack is not available) [ 21.009585] [ 21.011177] Freed by task 0: [ 21.014156] (stack is not available) [ 21.017829] [ 21.019430] The buggy address belongs to the object at ffff8801c8213100 [ 21.019430] which belongs to the cache fasync_cache of size 96 [ 21.032441] The buggy address is located 64 bytes inside of [ 21.032441] 96-byte region [ffff8801c8213100, ffff8801c8213160) [ 21.044105] The buggy address belongs to the page: [ 21.048999] page:ffffea00072084c0 count:1 mapcount:0 mapping: (null) index:0x0 [ 21.057218] flags: 0x8000000000000080(slab) [ 21.061503] page dumped because: kasan: bad access detected [ 21.067176] [ 21.068768] Memory state around the buggy address: [ 21.073672] ffff8801c8213000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 21.080997] ffff8801c8213080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.088323] >ffff8801c8213100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.095659] ^ [ 21.101074] ffff8801c8213180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.108396] ffff8801c8213200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.115815] ================================================================== [ 21.123144] Disabling lock debugging due to kernel taint [ 21.128863] Kernel panic - not syncing: panic_on_warn set ... [ 21.128863] [ 21.136198] CPU: 0 PID: 3325 Comm: syzkaller973178 Tainted: G B 4.9.75-g06fe41f #16 [ 21.145092] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 21.155639] ffff8801c82879a8 ffffffff81d93049 ffffffff84195be7 ffff8801c8287a80 [ 21.163592] 0000000000000000 ffff8801c8213140 ffff8801c82e8238 ffff8801c8287a70 [ 21.171548] ffffffff8142e281 0000000041b58ab3 ffffffff84189648 ffffffff8142e0c5 [ 21.179501] Call Trace: [ 21.182057] [] dump_stack+0xc1/0x128 [ 21.187387] [] panic+0x1bc/0x3a8 [ 21.192369] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 21.200565] [] ? preempt_schedule+0x25/0x30 [ 21.206502] [] ? ___preempt_schedule+0x16/0x18 [ 21.212710] [] kasan_end_report+0x50/0x50 [ 21.218474] [] kasan_report+0x167/0x360 [ 21.224062] [] ? sg_remove_request+0x103/0x120 [ 21.230258] [] __asan_report_load8_noabort+0x14/0x20 [ 21.236975] [] sg_remove_request+0x103/0x120 [ 21.242996] [] sg_finish_rem_req+0x295/0x340 [ 21.249016] [] sg_read+0xa1c/0x1440 [ 21.254259] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.260893] [] ? __raw_spin_lock_init+0x1c/0x100 [ 21.267285] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 21.274697] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.281329] [] __vfs_read+0x103/0x670 [ 21.286752] [] ? default_llseek+0x290/0x290 [ 21.294341] [] ? fsnotify+0x86/0xf30 [ 21.299670] [] ? fsnotify+0xf30/0xf30 [ 21.305096] [] ? avc_policy_seqno+0x9/0x20 [ 21.310955] [] ? selinux_file_permission+0x82/0x460 [ 21.317585] [] ? security_file_permission+0x89/0x1e0 [ 21.324304] [] ? rw_verify_area+0xe5/0x2b0 [ 21.331031] [] vfs_read+0x11e/0x380 [ 21.336709] [] SyS_read+0xd9/0x1b0 [ 21.341873] [] ? vfs_copy_file_range+0x740/0x740 [ 21.348242] [] ? do_fast_syscall_32+0xcf/0x890 [ 21.354446] [] ? vfs_copy_file_range+0x740/0x740 [ 21.360825] [] do_fast_syscall_32+0x2f7/0x890 [ 21.366934] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 21.373565] [] entry_SYSENTER_compat+0x74/0x83 [ 21.380218] Dumping ftrace buffer: [ 21.383732] (ftrace buffer empty) [ 21.387410] Kernel Offset: disabled [ 21.391002] Rebooting in 86400 seconds..