[....] Starting enhanced syslogd: rsyslogd[ 10.810186] audit: type=1400 audit(1516095026.046:4): 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 '10.128.0.12' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 18.720595] ================================================================== [ 18.721775] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 18.722756] Read of size 8 at addr ffff8801cb672140 by task syzkaller681746/3326 [ 18.723810] [ 18.724065] CPU: 1 PID: 3326 Comm: syzkaller681746 Not tainted 4.9.76-g8dec074 #13 [ 18.725076] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 18.726318] ffff8801c9bc7ab0 ffffffff81d93169 ffffea00072d9c80 ffff8801cb672140 [ 18.727576] 0000000000000000 ffff8801cb672140 ffff8801d7ed4438 ffff8801c9bc7ae8 [ 18.728742] ffffffff8153cb43 ffff8801cb672140 0000000000000008 0000000000000000 [ 18.729947] Call Trace: [ 18.730306] [] dump_stack+0xc1/0x128 [ 18.731049] [] print_address_description+0x73/0x280 [ 18.731928] [] kasan_report+0x275/0x360 [ 18.732672] [] ? sg_remove_request+0x103/0x120 [ 18.733562] [] __asan_report_load8_noabort+0x14/0x20 [ 18.734724] [] sg_remove_request+0x103/0x120 [ 18.735699] [] sg_finish_rem_req+0x295/0x340 [ 18.736527] [] sg_read+0xa1c/0x1440 [ 18.737262] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 18.738340] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 18.739375] [] ? fasync_helper+0x37/0xb0 [ 18.740186] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 18.743606] [] __vfs_read+0x103/0x670 [ 18.749676] [] ? default_llseek+0x290/0x290 [ 18.755628] [] ? fsnotify+0x86/0xf30 [ 18.760958] [] ? fsnotify+0xf30/0xf30 [ 18.766380] [] ? avc_policy_seqno+0x9/0x20 [ 18.772232] [] ? selinux_file_permission+0x82/0x460 [ 18.778875] [] ? security_file_permission+0x89/0x1e0 [ 18.785600] [] ? rw_verify_area+0xe5/0x2b0 [ 18.791455] [] vfs_read+0x11e/0x380 [ 18.796700] [] SyS_read+0xd9/0x1b0 [ 18.801859] [] ? vfs_copy_file_range+0x740/0x740 [ 18.808233] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 18.815040] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 18.821588] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 18.828134] [ 18.829732] Allocated by task 0: [ 18.833064] (stack is not available) [ 18.836740] [ 18.838335] Freed by task 0: [ 18.841316] (stack is not available) [ 18.844996] [ 18.846595] The buggy address belongs to the object at ffff8801cb672100 [ 18.846595] which belongs to the cache fasync_cache of size 96 [ 18.859220] The buggy address is located 64 bytes inside of [ 18.859220] 96-byte region [ffff8801cb672100, ffff8801cb672160) [ 18.870887] The buggy address belongs to the page: [ 18.875788] page:ffffea00072d9c80 count:1 mapcount:0 mapping: (null) index:0x0 [ 18.884023] flags: 0x8000000000000080(slab) [ 18.888403] page dumped because: kasan: bad access detected [ 18.894080] [ 18.895676] Memory state around the buggy address: [ 18.901007] ffff8801cb672000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 18.908340] ffff8801cb672080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 18.915667] >ffff8801cb672100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 18.922995] ^ [ 18.928416] ffff8801cb672180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 18.935742] ffff8801cb672200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 18.943075] ================================================================== [ 18.950412] Disabling lock debugging due to kernel taint [ 18.955891] Kernel panic - not syncing: panic_on_warn set ... [ 18.955891] [ 18.963235] CPU: 1 PID: 3326 Comm: syzkaller681746 Tainted: G B 4.9.76-g8dec074 #13 [ 18.972127] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 18.981455] ffff8801c9bc7a08 ffffffff81d93169 ffffffff84195c2f ffff8801c9bc7ae0 [ 18.989434] 0000000000000000 ffff8801cb672140 ffff8801d7ed4438 ffff8801c9bc7ad0 [ 18.997414] ffffffff8142e371 0000000041b58ab3 ffffffff84189690 ffffffff8142e1b5 [ 19.005409] Call Trace: [ 19.007969] [] dump_stack+0xc1/0x128 [ 19.013306] [] panic+0x1bc/0x3a8 [ 19.018292] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 19.026489] [] ? preempt_schedule+0x25/0x30 [ 19.032429] [] ? ___preempt_schedule+0x16/0x18 [ 19.038645] [] kasan_end_report+0x50/0x50 [ 19.044413] [] kasan_report+0x167/0x360 [ 19.050012] [] ? sg_remove_request+0x103/0x120 [ 19.056221] [] __asan_report_load8_noabort+0x14/0x20 [ 19.062943] [] sg_remove_request+0x103/0x120 [ 19.068972] [] sg_finish_rem_req+0x295/0x340 [ 19.074999] [] sg_read+0xa1c/0x1440 [ 19.080249] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.086894] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 19.093880] [] ? fasync_helper+0x37/0xb0 [ 19.099562] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 19.106196] [] __vfs_read+0x103/0x670 [ 19.111629] [] ? default_llseek+0x290/0x290 [ 19.117570] [] ? fsnotify+0x86/0xf30 [ 19.122902] [] ? fsnotify+0xf30/0xf30 [ 19.128338] [] ? avc_policy_seqno+0x9/0x20 [ 19.134191] [] ? selinux_file_permission+0x82/0x460 [ 19.140826] [] ? security_file_permission+0x89/0x1e0 [ 19.147554] [] ? rw_verify_area+0xe5/0x2b0 [ 19.153409] [] vfs_read+0x11e/0x380 [ 19.158656] [] SyS_read+0xd9/0x1b0 [ 19.163816] [] ? vfs_copy_file_range+0x740/0x740 [ 19.170191] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 19.177001] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 19.183562] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 19.190554] Dumping ftrace buffer: [ 19.194079] (ftrace buffer empty) [ 19.197759] Kernel Offset: disabled [ 19.201357] Rebooting in 86400 seconds..