[....] Starting enhanced syslogd: rsyslogd[ 10.756305] audit: type=1400 audit(1516043440.349:4): 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 '10.128.15.222' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 32.731281] ================================================================== [ 32.732412] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 32.733348] Read of size 8 at addr ffff8801c8af6140 by task syzkaller951619/3343 [ 32.734363] [ 32.734599] CPU: 1 PID: 3343 Comm: syzkaller951619 Not tainted 4.9.76-g8dec074 #23 [ 32.735635] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.736863] ffff8801c905fa50 ffffffff81d93169 ffffea000722bd80 ffff8801c8af6140 [ 32.738095] 0000000000000000 ffff8801c8af6140 ffff8801c7468238 ffff8801c905fa88 [ 32.739299] ffffffff8153cb43 ffff8801c8af6140 0000000000000008 0000000000000000 [ 32.740507] Call Trace: [ 32.740871] [] dump_stack+0xc1/0x128 [ 32.741588] [] print_address_description+0x73/0x280 [ 32.742479] [] kasan_report+0x275/0x360 [ 32.743228] [] ? sg_remove_request+0x103/0x120 [ 32.744117] [] __asan_report_load8_noabort+0x14/0x20 [ 32.745007] [] sg_remove_request+0x103/0x120 [ 32.745810] [] sg_finish_rem_req+0x295/0x340 [ 32.746641] [] sg_read+0xa1c/0x1440 [ 32.747344] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 32.748316] [] ? __raw_spin_lock_init+0x1c/0x100 [ 32.749162] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 32.750120] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 32.751010] [] __vfs_read+0x103/0x670 [ 32.751734] [] ? default_llseek+0x290/0x290 [ 32.757678] [] ? fsnotify+0x86/0xf30 [ 32.763020] [] ? fsnotify+0xf30/0xf30 [ 32.768459] [] ? avc_policy_seqno+0x9/0x20 [ 32.774328] [] ? selinux_file_permission+0x82/0x460 [ 32.780972] [] ? security_file_permission+0x89/0x1e0 [ 32.787709] [] ? rw_verify_area+0xe5/0x2b0 [ 32.793564] [] vfs_read+0x11e/0x380 [ 32.798811] [] SyS_read+0xd9/0x1b0 [ 32.803970] [] ? vfs_copy_file_range+0x740/0x740 [ 32.810347] [] ? do_fast_syscall_32+0xcf/0x890 [ 32.816550] [] ? vfs_copy_file_range+0x740/0x740 [ 32.822927] [] do_fast_syscall_32+0x2f7/0x890 [ 32.829042] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 32.835677] [] entry_SYSENTER_compat+0x74/0x83 [ 32.841880] [ 32.843479] Allocated by task 0: [ 32.846810] (stack is not available) [ 32.850492] [ 32.852100] Freed by task 0: [ 32.855085] (stack is not available) [ 32.858765] [ 32.860366] The buggy address belongs to the object at ffff8801c8af6100 [ 32.860366] which belongs to the cache fasync_cache of size 96 [ 32.873003] The buggy address is located 64 bytes inside of [ 32.873003] 96-byte region [ffff8801c8af6100, ffff8801c8af6160) [ 32.884673] The buggy address belongs to the page: [ 32.889586] page:ffffea000722bd80 count:1 mapcount:0 mapping: (null) index:0x0 [ 32.897813] flags: 0x8000000000000080(slab) [ 32.902115] page dumped because: kasan: bad access detected [ 32.907802] [ 32.909397] Memory state around the buggy address: [ 32.914298] ffff8801c8af6000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 32.921630] ffff8801c8af6080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 32.928966] >ffff8801c8af6100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 32.936293] ^ [ 32.941711] ffff8801c8af6180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 32.949038] ffff8801c8af6200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 32.956363] ================================================================== [ 32.963690] Disabling lock debugging due to kernel taint [ 32.969220] Kernel panic - not syncing: panic_on_warn set ... [ 32.969220] [ 32.976564] CPU: 1 PID: 3343 Comm: syzkaller951619 Tainted: G B 4.9.76-g8dec074 #23 [ 32.985457] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.994786] ffff8801c905f9a8 ffffffff81d93169 ffffffff84195c2f ffff8801c905fa80 [ 33.002780] 0000000000000000 ffff8801c8af6140 ffff8801c7468238 ffff8801c905fa70 [ 33.010750] ffffffff8142e371 0000000041b58ab3 ffffffff84189690 ffffffff8142e1b5 [ 33.018740] Call Trace: [ 33.021303] [] dump_stack+0xc1/0x128 [ 33.026650] [] panic+0x1bc/0x3a8 [ 33.031639] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 33.039841] [] ? preempt_schedule+0x25/0x30 [ 33.045793] [] ? ___preempt_schedule+0x16/0x18 [ 33.052018] [] kasan_end_report+0x50/0x50 [ 33.057792] [] kasan_report+0x167/0x360 [ 33.063398] [] ? sg_remove_request+0x103/0x120 [ 33.069623] [] __asan_report_load8_noabort+0x14/0x20 [ 33.076366] [] sg_remove_request+0x103/0x120 [ 33.082402] [] sg_finish_rem_req+0x295/0x340 [ 33.088432] [] sg_read+0xa1c/0x1440 [ 33.093687] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 33.100333] [] ? __raw_spin_lock_init+0x1c/0x100 [ 33.106712] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 33.113538] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 33.120178] [] __vfs_read+0x103/0x670 [ 33.125610] [] ? default_llseek+0x290/0x290 [ 33.131562] [] ? fsnotify+0x86/0xf30 [ 33.136906] [] ? fsnotify+0xf30/0xf30 [ 33.142330] [] ? avc_policy_seqno+0x9/0x20 [ 33.148192] [] ? selinux_file_permission+0x82/0x460 [ 33.154828] [] ? security_file_permission+0x89/0x1e0 [ 33.161552] [] ? rw_verify_area+0xe5/0x2b0 [ 33.167441] [] vfs_read+0x11e/0x380 [ 33.172692] [] SyS_read+0xd9/0x1b0 [ 33.177855] [] ? vfs_copy_file_range+0x740/0x740 [ 33.184237] [] ? do_fast_syscall_32+0xcf/0x890 [ 33.190458] [] ? vfs_copy_file_range+0x740/0x740 [ 33.196853] [] do_fast_syscall_32+0x2f7/0x890 [ 33.202981] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 33.209620] [] entry_SYSENTER_compat+0x74/0x83 [ 33.216271] Dumping ftrace buffer: [ 33.219787] (ftrace buffer empty) [ 33.223474] Kernel Offset: disabled [ 33.227072] Rebooting in 86400 seconds..