[....] Starting enhanced syslogd: rsyslogd[ 11.256608] audit: type=1400 audit(1516025988.995:4): avc: denied { syslog } for pid=3183 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 '10.128.0.49' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 20.990448] ================================================================== [ 20.997848] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 21.004926] Read of size 8 at addr ffff8801cc537140 by task syzkaller069246/3332 [ 21.012424] [ 21.014027] CPU: 0 PID: 3332 Comm: syzkaller069246 Not tainted 4.9.76-g8dec074 #23 [ 21.021710] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 21.031038] ffff8801c668f940 ffffffff81d93169 ffffea0007314dc0 ffff8801cc537140 [ 21.039010] 0000000000000000 ffff8801cc537140 ffff8801cd594438 ffff8801c668f978 [ 21.046966] ffffffff8153cb43 ffff8801cc537140 0000000000000008 0000000000000000 [ 21.054936] Call Trace: [ 21.057495] [] dump_stack+0xc1/0x128 [ 21.062829] [] print_address_description+0x73/0x280 [ 21.069464] [] kasan_report+0x275/0x360 [ 21.075058] [] ? sg_remove_request+0x103/0x120 [ 21.081272] [] __asan_report_load8_noabort+0x14/0x20 [ 21.088000] [] sg_remove_request+0x103/0x120 [ 21.094038] [] sg_finish_rem_req+0x295/0x340 [ 21.100067] [] sg_read+0xa1c/0x1440 [ 21.105319] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.111953] [] ? fsnotify+0xf30/0xf30 [ 21.117383] [] ? avc_policy_seqno+0x9/0x20 [ 21.123243] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 21.130251] [] ? security_file_permission+0x89/0x1e0 [ 21.136975] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.143612] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.150257] [] compat_do_readv_writev+0x522/0x760 [ 21.156737] [] ? do_pwritev+0x1a0/0x1a0 [ 21.162336] [] ? _raw_spin_unlock+0x2c/0x50 [ 21.168285] [] ? fasync_helper+0x7a/0xb0 [ 21.173964] [] ? __pmd_alloc+0x410/0x410 [ 21.179663] [] compat_readv+0xe3/0x150 [ 21.185166] [] do_compat_readv+0xf4/0x1d0 [ 21.190928] [] ? compat_readv+0x150/0x150 [ 21.196692] [] compat_SyS_readv+0x26/0x30 [ 21.202462] [] ? SyS_pwritev2+0x80/0x80 [ 21.208063] [] do_fast_syscall_32+0x2f7/0x890 [ 21.214189] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 21.220831] [] entry_SYSENTER_compat+0x74/0x83 [ 21.227031] [ 21.228626] Allocated by task 0: [ 21.233081] (stack is not available) [ 21.236762] [ 21.238361] Freed by task 0: [ 21.241361] (stack is not available) [ 21.245043] [ 21.246639] The buggy address belongs to the object at ffff8801cc537100 [ 21.246639] which belongs to the cache fasync_cache of size 96 [ 21.259268] The buggy address is located 64 bytes inside of [ 21.259268] 96-byte region [ffff8801cc537100, ffff8801cc537160) [ 21.270942] The buggy address belongs to the page: [ 21.275843] page:ffffea0007314dc0 count:1 mapcount:0 mapping: (null) index:0x0 [ 21.284065] flags: 0x8000000000000080(slab) [ 21.288350] page dumped because: kasan: bad access detected [ 21.294023] [ 21.295616] Memory state around the buggy address: [ 21.300513] ffff8801cc537000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 21.307863] ffff8801cc537080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.315188] >ffff8801cc537100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.322520] ^ [ 21.327936] ffff8801cc537180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.335269] ffff8801cc537200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.342600] ================================================================== [ 21.349930] Disabling lock debugging due to kernel taint [ 21.355571] Kernel panic - not syncing: panic_on_warn set ... [ 21.355571] [ 21.362915] CPU: 0 PID: 3332 Comm: syzkaller069246 Tainted: G B 4.9.76-g8dec074 #23 [ 21.371809] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 21.381144] ffff8801c668f898 ffffffff81d93169 ffffffff84195c2f ffff8801c668f970 [ 21.389104] 0000000000000000 ffff8801cc537140 ffff8801cd594438 ffff8801c668f960 [ 21.397057] ffffffff8142e371 0000000041b58ab3 ffffffff84189690 ffffffff8142e1b5 [ 21.405017] Call Trace: [ 21.407585] [] dump_stack+0xc1/0x128 [ 21.412920] [] panic+0x1bc/0x3a8 [ 21.417906] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 21.426206] [] ? preempt_schedule+0x25/0x30 [ 21.432146] [] ? ___preempt_schedule+0x16/0x18 [ 21.438355] [] kasan_end_report+0x50/0x50 [ 21.444119] [] kasan_report+0x167/0x360 [ 21.449712] [] ? sg_remove_request+0x103/0x120 [ 21.455925] [] __asan_report_load8_noabort+0x14/0x20 [ 21.462645] [] sg_remove_request+0x103/0x120 [ 21.468670] [] sg_finish_rem_req+0x295/0x340 [ 21.474705] [] sg_read+0xa1c/0x1440 [ 21.479950] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.486592] [] ? fsnotify+0xf30/0xf30 [ 21.492021] [] ? avc_policy_seqno+0x9/0x20 [ 21.497883] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 21.504865] [] ? security_file_permission+0x89/0x1e0 [ 21.511587] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.518222] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.524861] [] compat_do_readv_writev+0x522/0x760 [ 21.531329] [] ? do_pwritev+0x1a0/0x1a0 [ 21.536924] [] ? _raw_spin_unlock+0x2c/0x50 [ 21.542860] [] ? fasync_helper+0x7a/0xb0 [ 21.548547] [] ? __pmd_alloc+0x410/0x410 [ 21.554224] [] compat_readv+0xe3/0x150 [ 21.559742] [] do_compat_readv+0xf4/0x1d0 [ 21.565511] [] ? compat_readv+0x150/0x150 [ 21.571300] [] compat_SyS_readv+0x26/0x30 [ 21.577065] [] ? SyS_pwritev2+0x80/0x80 [ 21.582657] [] do_fast_syscall_32+0x2f7/0x890 [ 21.588768] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 21.595411] [] entry_SYSENTER_compat+0x74/0x83 [ 21.602059] Dumping ftrace buffer: [ 21.605572] (ftrace buffer empty) [ 21.609248] Kernel Offset: disabled [ 21.612845] Rebooting in 86400 seconds..