[....] Starting enhanced syslogd: rsyslogd[ 10.049042] audit: type=1400 audit(1515816731.911:4): 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 '10.128.0.18' (ECDSA) to the list of known hosts. executing program executing program syzkaller login: [ 21.329160] ================================================================== [ 21.330328] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 21.331260] Read of size 8 at addr ffff8801c9647240 by task syzkaller301461/3334 [ 21.332443] [ 21.332674] CPU: 1 PID: 3334 Comm: syzkaller301461 Not tainted 4.9.76-g8e170a5 #11 [ 21.333702] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 21.334951] ffff8801c8457ab0 ffffffff81d93149 ffffea00072591c0 ffff8801c9647240 [ 21.336084] 0000000000000000 ffff8801c9647240 ffff8801c8920238 ffff8801c8457ae8 [ 21.337331] ffffffff8153cb43 ffff8801c9647240 0000000000000008 0000000000000000 [ 21.338510] Call Trace: [ 21.338872] [] dump_stack+0xc1/0x128 [ 21.342162] [] print_address_description+0x73/0x280 [ 21.343063] [] kasan_report+0x275/0x360 [ 21.343808] [] ? sg_remove_request+0x103/0x120 [ 21.344630] [] __asan_report_load8_noabort+0x14/0x20 [ 21.345518] [] sg_remove_request+0x103/0x120 [ 21.346318] [] sg_finish_rem_req+0x295/0x340 [ 21.347116] [] sg_read+0xa1c/0x1440 [ 21.347842] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.348723] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 21.352128] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.358764] [] __vfs_read+0x103/0x670 [ 21.364189] [] ? default_llseek+0x290/0x290 [ 21.370134] [] ? fsnotify+0x86/0xf30 [ 21.375471] [] ? fsnotify+0xf30/0xf30 [ 21.380893] [] ? avc_policy_seqno+0x9/0x20 [ 21.386754] [] ? selinux_file_permission+0x82/0x460 [ 21.393400] [] ? security_file_permission+0x89/0x1e0 [ 21.400122] [] ? rw_verify_area+0xe5/0x2b0 [ 21.405987] [] vfs_read+0x11e/0x380 [ 21.411231] [] SyS_read+0xd9/0x1b0 [ 21.416392] [] ? vfs_copy_file_range+0x740/0x740 [ 21.422781] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 21.429592] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 21.436143] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 21.442701] [ 21.444298] Allocated by task 0: [ 21.447628] (stack is not available) [ 21.451304] [ 21.452898] Freed by task 0: [ 21.455883] (stack is not available) [ 21.459558] [ 21.461161] The buggy address belongs to the object at ffff8801c9647200 [ 21.461161] which belongs to the cache fasync_cache of size 96 [ 21.473789] The buggy address is located 64 bytes inside of [ 21.473789] 96-byte region [ffff8801c9647200, ffff8801c9647260) [ 21.485456] The buggy address belongs to the page: [ 21.490364] page:ffffea00072591c0 count:1 mapcount:0 mapping: (null) index:0x0 [ 21.498599] flags: 0x8000000000000080(slab) [ 21.502898] page dumped because: kasan: bad access detected [ 21.508583] [ 21.510176] Memory state around the buggy address: [ 21.515076] ffff8801c9647100: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 21.522411] ffff8801c9647180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc executing program [ 21.529749] >ffff8801c9647200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.537075] ^ [ 21.542503] ffff8801c9647280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.549844] ffff8801c9647300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.557170] ================================================================== [ 21.564494] Disabling lock debugging due to kernel taint [ 21.571547] Kernel panic - not syncing: panic_on_warn set ... [ 21.571547] [ 21.578922] CPU: 1 PID: 3334 Comm: syzkaller301461 Tainted: G B 4.9.76-g8e170a5 #11 [ 21.587814] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 21.597139] ffff8801c8457a08 ffffffff81d93149 ffffffff84195c17 ffff8801c8457ae0 [ 21.605111] 0000000000000000 ffff8801c9647240 ffff8801c8920238 ffff8801c8457ad0 [ 21.613059] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 21.621014] Call Trace: [ 21.623581] [] dump_stack+0xc1/0x128 [ 21.628923] [] panic+0x1bc/0x3a8 [ 21.633915] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 21.642116] [] ? preempt_schedule+0x25/0x30 [ 21.648056] [] ? ___preempt_schedule+0x16/0x18 [ 21.654269] [] kasan_end_report+0x50/0x50 [ 21.660035] [] kasan_report+0x167/0x360 [ 21.665644] [] ? sg_remove_request+0x103/0x120 [ 21.671846] [] __asan_report_load8_noabort+0x14/0x20 [ 21.678565] [] sg_remove_request+0x103/0x120 [ 21.684592] [] sg_finish_rem_req+0x295/0x340 [ 21.690623] [] sg_read+0xa1c/0x1440 [ 21.695869] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.702505] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 21.709485] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.716121] [] __vfs_read+0x103/0x670 [ 21.721553] [] ? default_llseek+0x290/0x290 [ 21.727492] [] ? fsnotify+0x86/0xf30 [ 21.732824] [] ? fsnotify+0xf30/0xf30 [ 21.738254] [] ? avc_policy_seqno+0x9/0x20 [ 21.744109] [] ? selinux_file_permission+0x82/0x460 [ 21.750855] [] ? security_file_permission+0x89/0x1e0 [ 21.757576] [] ? rw_verify_area+0xe5/0x2b0 [ 21.763427] [] vfs_read+0x11e/0x380 [ 21.768678] [] SyS_read+0xd9/0x1b0 [ 21.773844] [] ? vfs_copy_file_range+0x740/0x740 [ 21.780221] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 21.787028] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 21.793578] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 21.800154] Dumping ftrace buffer: [ 21.803923] (ftrace buffer empty) [ 21.807614] Kernel Offset: disabled [ 21.811208] Rebooting in 86400 seconds..