[....] Starting enhanced syslogd: rsyslogd[ 10.661663] audit: type=1400 audit(1516109766.852:4): avc: denied { syslog } for pid=3177 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[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.15.227' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 19.626229] ================================================================== [ 19.627355] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 19.628317] Read of size 8 at addr ffff8801cbf15140 by task syzkaller929338/3326 [ 19.629335] [ 19.629592] CPU: 1 PID: 3326 Comm: syzkaller929338 Not tainted 4.9.76-g8dec074 #13 [ 19.630638] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 19.631946] ffff8801cd3bfab0 ffffffff81d93169 ffffea00072fc540 ffff8801cbf15140 [ 19.633171] 0000000000000000 ffff8801cbf15140 ffff8801c97f4438 ffff8801cd3bfae8 [ 19.634345] ffffffff8153cb43 ffff8801cbf15140 0000000000000008 0000000000000000 [ 19.635492] Call Trace: [ 19.635858] [] dump_stack+0xc1/0x128 [ 19.636585] [] print_address_description+0x73/0x280 [ 19.637464] [] kasan_report+0x275/0x360 [ 19.638263] [] ? sg_remove_request+0x103/0x120 [ 19.639103] [] __asan_report_load8_noabort+0x14/0x20 [ 19.640037] [] sg_remove_request+0x103/0x120 [ 19.640897] [] sg_finish_rem_req+0x295/0x340 [ 19.641728] [] sg_read+0xa1c/0x1440 [ 19.642580] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.643483] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 19.644408] [] ? fasync_helper+0x37/0xb0 [ 19.645164] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.646118] [] __vfs_read+0x103/0x670 [ 19.650052] [] ? default_llseek+0x290/0x290 [ 19.655991] [] ? fsnotify+0x86/0xf30 [ 19.661326] [] ? fsnotify+0xf30/0xf30 [ 19.666763] [] ? avc_policy_seqno+0x9/0x20 [ 19.672617] [] ? selinux_file_permission+0x82/0x460 [ 19.679250] [] ? security_file_permission+0x89/0x1e0 [ 19.685983] [] ? rw_verify_area+0xe5/0x2b0 [ 19.691836] [] vfs_read+0x11e/0x380 [ 19.697081] [] SyS_read+0xd9/0x1b0 [ 19.702241] [] ? vfs_copy_file_range+0x740/0x740 [ 19.708618] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 19.715427] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 19.721985] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 19.728530] [ 19.730130] Allocated by task 0: [ 19.733460] (stack is not available) [ 19.737140] [ 19.738737] Freed by task 0: [ 19.741721] (stack is not available) [ 19.745412] [ 19.747011] The buggy address belongs to the object at ffff8801cbf15100 [ 19.747011] which belongs to the cache fasync_cache of size 96 [ 19.759640] The buggy address is located 64 bytes inside of [ 19.759640] 96-byte region [ffff8801cbf15100, ffff8801cbf15160) [ 19.771310] The buggy address belongs to the page: [ 19.776209] page:ffffea00072fc540 count:1 mapcount:0 mapping: (null) index:0x0 [ 19.784433] flags: 0x8000000000000080(slab) [ 19.788718] page dumped because: kasan: bad access detected [ 19.794393] [ 19.795995] Memory state around the buggy address: [ 19.800894] ffff8801cbf15000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 19.808220] ffff8801cbf15080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.815545] >ffff8801cbf15100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.822870] ^ [ 19.828289] ffff8801cbf15180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.835617] ffff8801cbf15200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 19.842949] ================================================================== [ 19.850276] Disabling lock debugging due to kernel taint [ 19.855778] Kernel panic - not syncing: panic_on_warn set ... [ 19.855778] [ 19.863125] CPU: 1 PID: 3326 Comm: syzkaller929338 Tainted: G B 4.9.76-g8dec074 #13 [ 19.872017] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 19.881344] ffff8801cd3bfa08 ffffffff81d93169 ffffffff84195c2f ffff8801cd3bfae0 [ 19.889327] 0000000000000000 ffff8801cbf15140 ffff8801c97f4438 ffff8801cd3bfad0 [ 19.897286] ffffffff8142e371 0000000041b58ab3 ffffffff84189690 ffffffff8142e1b5 [ 19.905262] Call Trace: [ 19.907820] [] dump_stack+0xc1/0x128 [ 19.913156] [] panic+0x1bc/0x3a8 [ 19.918143] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 19.926354] [] ? preempt_schedule+0x25/0x30 [ 19.932303] [] ? ___preempt_schedule+0x16/0x18 [ 19.938506] [] kasan_end_report+0x50/0x50 [ 19.944278] [] kasan_report+0x167/0x360 [ 19.949879] [] ? sg_remove_request+0x103/0x120 [ 19.956082] [] __asan_report_load8_noabort+0x14/0x20 [ 19.962805] [] sg_remove_request+0x103/0x120 [ 19.968832] [] sg_finish_rem_req+0x295/0x340 [ 19.974858] [] sg_read+0xa1c/0x1440 [ 19.980111] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.986750] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 19.993744] [] ? fasync_helper+0x37/0xb0 [ 19.999426] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 20.006077] [] __vfs_read+0x103/0x670 [ 20.011498] [] ? default_llseek+0x290/0x290 [ 20.017452] [] ? fsnotify+0x86/0xf30 [ 20.022806] [] ? fsnotify+0xf30/0xf30 [ 20.028232] [] ? avc_policy_seqno+0x9/0x20 [ 20.034093] [] ? selinux_file_permission+0x82/0x460 [ 20.040739] [] ? security_file_permission+0x89/0x1e0 [ 20.047464] [] ? rw_verify_area+0xe5/0x2b0 [ 20.053314] [] vfs_read+0x11e/0x380 [ 20.058558] [] SyS_read+0xd9/0x1b0 [ 20.063718] [] ? vfs_copy_file_range+0x740/0x740 [ 20.070100] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 20.076922] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 20.083474] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 20.090424] Dumping ftrace buffer: [ 20.093939] (ftrace buffer empty) [ 20.097617] Kernel Offset: disabled [ 20.101216] Rebooting in 86400 seconds..