[....] Starting enhanced syslogd: rsyslogd[ 10.847379] audit: type=1400 audit(1515793232.010:4): avc: denied { syslog } for pid=3172 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 '10.128.0.30' (ECDSA) to the list of known hosts. executing program executing program syzkaller login: [ 18.832581] ================================================================== [ 18.833692] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 18.834623] Read of size 8 at addr ffff8801cc6f7140 by task syzkaller498764/3322 [ 18.835605] [ 18.835854] CPU: 0 PID: 3322 Comm: syzkaller498764 Not tainted 4.9.76-g8e170a5 #21 [ 18.836876] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 18.838095] ffff8801c81f7940 ffffffff81d93149 ffffea000731bdc0 ffff8801cc6f7140 [ 18.839236] 0000000000000000 ffff8801cc6f7140 ffff8801c81e2338 ffff8801c81f7978 [ 18.840370] ffffffff8153cb43 ffff8801cc6f7140 0000000000000008 0000000000000000 [ 18.841513] Call Trace: [ 18.841870] [] dump_stack+0xc1/0x128 [ 18.842583] [] print_address_description+0x73/0x280 [ 18.843469] [] kasan_report+0x275/0x360 [ 18.844209] [] ? sg_remove_request+0x103/0x120 [ 18.845052] [] __asan_report_load8_noabort+0x14/0x20 [ 18.845940] [] sg_remove_request+0x103/0x120 [ 18.846754] [] sg_finish_rem_req+0x295/0x340 [ 18.847551] [] sg_read+0xa1c/0x1440 [ 18.848270] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 18.849181] [] ? fsnotify+0xf30/0xf30 [ 18.849920] [] ? avc_policy_seqno+0x9/0x20 [ 18.850696] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 18.851697] [] ? security_file_permission+0x89/0x1e0 [ 18.852582] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 18.858631] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 18.865261] [] compat_do_readv_writev+0x522/0x760 [ 18.871726] [] ? do_pwritev+0x1a0/0x1a0 [ 18.877324] [] ? _raw_spin_unlock+0x2c/0x50 [ 18.883260] [] ? __fget+0x201/0x3a0 [ 18.888505] [] ? __fget+0x228/0x3a0 [ 18.893749] [] ? __fget+0x47/0x3a0 [ 18.898903] [] compat_readv+0xe3/0x150 [ 18.904407] [] do_compat_readv+0xf4/0x1d0 [ 18.910169] [] ? compat_readv+0x150/0x150 [ 18.915932] [] compat_SyS_readv+0x26/0x30 [ 18.921692] [] ? SyS_pwritev2+0x80/0x80 [ 18.927281] [] do_fast_syscall_32+0x2f7/0x890 [ 18.933388] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 18.940024] [] entry_SYSENTER_compat+0x74/0x83 [ 18.946219] [ 18.947811] Allocated by task 0: [ 18.951146] (stack is not available) [ 18.954819] [ 18.956410] Freed by task 0: [ 18.959400] (stack is not available) [ 18.963081] [ 18.964673] The buggy address belongs to the object at ffff8801cc6f7100 [ 18.964673] which belongs to the cache fasync_cache of size 96 [ 18.977292] The buggy address is located 64 bytes inside of [ 18.977292] 96-byte region [ffff8801cc6f7100, ffff8801cc6f7160) [ 18.988962] The buggy address belongs to the page: [ 18.993855] page:ffffea000731bdc0 count:1 mapcount:0 mapping: (null) index:0x0 [ 19.002074] flags: 0x8000000000000080(slab) [ 19.006366] page dumped because: kasan: bad access detected [ 19.012037] [ 19.013628] Memory state around the buggy address: [ 19.018521] ffff8801cc6f7000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 19.025851] ffff8801cc6f7080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc executing program [ 19.033174] >ffff8801cc6f7100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.040498] ^ [ 19.045912] ffff8801cc6f7180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.053233] ffff8801cc6f7200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.060554] ================================================================== [ 19.067876] Disabling lock debugging due to kernel taint [ 19.074023] Kernel panic - not syncing: panic_on_warn set ... [ 19.074023] [ 19.081390] CPU: 0 PID: 3322 Comm: syzkaller498764 Tainted: G B 4.9.76-g8e170a5 #21 [ 19.090280] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 19.099602] ffff8801c81f7898 ffffffff81d93149 ffffffff84195c17 ffff8801c81f7970 [ 19.107567] 0000000000000000 ffff8801cc6f7140 ffff8801c81e2338 ffff8801c81f7960 [ 19.115519] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 19.123475] Call Trace: [ 19.126034] [] dump_stack+0xc1/0x128 [ 19.131365] [] panic+0x1bc/0x3a8 [ 19.136352] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 19.144557] [] ? preempt_schedule+0x25/0x30 [ 19.150497] [] ? ___preempt_schedule+0x16/0x18 [ 19.156698] [] kasan_end_report+0x50/0x50 [ 19.162462] [] kasan_report+0x167/0x360 [ 19.168056] [] ? sg_remove_request+0x103/0x120 [ 19.174266] [] __asan_report_load8_noabort+0x14/0x20 [ 19.180994] [] sg_remove_request+0x103/0x120 [ 19.187018] [] sg_finish_rem_req+0x295/0x340 [ 19.193042] [] sg_read+0xa1c/0x1440 [ 19.198294] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.204933] [] ? fsnotify+0xf30/0xf30 [ 19.210350] [] ? avc_policy_seqno+0x9/0x20 [ 19.216202] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 19.223182] [] ? security_file_permission+0x89/0x1e0 [ 19.229901] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.236536] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.243168] [] compat_do_readv_writev+0x522/0x760 [ 19.249634] [] ? do_pwritev+0x1a0/0x1a0 [ 19.255224] [] ? _raw_spin_unlock+0x2c/0x50 [ 19.261163] [] ? __fget+0x201/0x3a0 [ 19.266405] [] ? __fget+0x228/0x3a0 [ 19.271647] [] ? __fget+0x47/0x3a0 [ 19.276803] [] compat_readv+0xe3/0x150 [ 19.282306] [] do_compat_readv+0xf4/0x1d0 [ 19.288070] [] ? compat_readv+0x150/0x150 [ 19.293834] [] compat_SyS_readv+0x26/0x30 [ 19.299598] [] ? SyS_pwritev2+0x80/0x80 [ 19.305188] [] do_fast_syscall_32+0x2f7/0x890 [ 19.311307] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 19.317948] [] entry_SYSENTER_compat+0x74/0x83 [ 19.324593] Dumping ftrace buffer: [ 19.328113] (ftrace buffer empty) [ 19.331789] Kernel Offset: disabled [ 19.335380] Rebooting in 86400 seconds..