[....] Starting enhanced syslogd: rsyslogd[ 10.981115] audit: type=1400 audit(1520658265.834:4): avc: denied { syslog } for pid=3571 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 '10.128.0.6' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 27.428733] ================================================================== [ 27.429825] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 27.430788] Read of size 8 at addr ffff8801c5a9d140 by task syzkaller943256/3736 [ 27.431784] [ 27.432018] CPU: 1 PID: 3736 Comm: syzkaller943256 Not tainted 4.9.86-g00db063 #52 [ 27.433026] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.434247] ffff8801d8befa60 ffffffff81d956f9 ffffea000716a740 ffff8801c5a9d140 [ 27.435413] 0000000000000000 ffff8801c5a9d140 ffff8801d8ad0238 ffff8801d8befa98 [ 27.436560] ffffffff8153e083 ffff8801c5a9d140 0000000000000008 0000000000000000 [ 27.437709] Call Trace: [ 27.438083] [] dump_stack+0xc1/0x128 [ 27.438800] [] print_address_description+0x73/0x280 [ 27.439709] [] kasan_report+0x275/0x360 [ 27.440485] [] ? sg_remove_request+0x103/0x120 [ 27.441319] [] __asan_report_load8_noabort+0x14/0x20 [ 27.442206] [] sg_remove_request+0x103/0x120 [ 27.443174] [] sg_finish_rem_req+0x295/0x340 [ 27.443975] [] sg_read+0xa16/0x1440 [ 27.444676] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 27.445554] [] ? fasync_insert_entry+0x147/0x2e0 [ 27.446410] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 27.447290] [] __vfs_read+0x103/0x670 [ 27.448015] [] ? default_llseek+0x290/0x290 [ 27.448815] [] ? fsnotify+0x86/0xf30 [ 27.449539] [] ? fsnotify+0xf30/0xf30 [ 27.454958] [] ? avc_policy_seqno+0x9/0x20 [ 27.460808] [] ? selinux_file_permission+0x82/0x460 [ 27.467439] [] ? security_file_permission+0x89/0x1e0 [ 27.474160] [] ? rw_verify_area+0xe5/0x2b0 [ 27.480009] [] vfs_read+0x11e/0x380 [ 27.485252] [] SyS_read+0xd9/0x1b0 [ 27.490407] [] ? vfs_copy_file_range+0x740/0x740 [ 27.496781] [] ? do_syscall_64+0x48/0x490 [ 27.502545] [] ? vfs_copy_file_range+0x740/0x740 [ 27.508917] [] do_syscall_64+0x1a4/0x490 [ 27.514597] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 27.521486] [ 27.523086] Allocated by task 0: [ 27.526422] (stack is not available) [ 27.530099] [ 27.531693] Freed by task 0: [ 27.534675] (stack is not available) [ 27.538354] [ 27.539952] The buggy address belongs to the object at ffff8801c5a9d100 [ 27.539952] which belongs to the cache fasync_cache of size 96 [ 27.552576] The buggy address is located 64 bytes inside of [ 27.552576] 96-byte region [ffff8801c5a9d100, ffff8801c5a9d160) [ 27.564243] The buggy address belongs to the page: [ 27.569139] page:ffffea000716a740 count:1 mapcount:0 mapping: (null) index:0x0 [ 27.577360] flags: 0x8000000000000080(slab) [ 27.581646] page dumped because: kasan: bad access detected [ 27.587320] [ 27.588916] Memory state around the buggy address: [ 27.593810] ffff8801c5a9d000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 27.601136] ffff8801c5a9d080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.608469] >ffff8801c5a9d100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.615791] ^ [ 27.621209] ffff8801c5a9d180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.628534] ffff8801c5a9d200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.635945] ================================================================== [ 27.643268] Disabling lock debugging due to kernel taint [ 27.648876] Kernel panic - not syncing: panic_on_warn set ... [ 27.648876] [ 27.656226] CPU: 1 PID: 3736 Comm: syzkaller943256 Tainted: G B 4.9.86-g00db063 #52 [ 27.665114] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.674436] ffff8801d8bef9b8 ffffffff81d956f9 ffffffff84197a0f ffff8801d8befa90 [ 27.682400] 0000000000000000 ffff8801c5a9d140 ffff8801d8ad0238 ffff8801d8befa80 [ 27.690378] ffffffff8142f531 0000000041b58ab3 ffffffff8418b470 ffffffff8142f375 [ 27.698333] Call Trace: [ 27.700891] [] dump_stack+0xc1/0x128 [ 27.706224] [] panic+0x1bc/0x3a8 [ 27.711208] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 27.719404] [] ? preempt_schedule+0x25/0x30 [ 27.725342] [] ? ___preempt_schedule+0x16/0x18 [ 27.731542] [] kasan_end_report+0x50/0x50 [ 27.737306] [] kasan_report+0x167/0x360 [ 27.742901] [] ? sg_remove_request+0x103/0x120 [ 27.749098] [] __asan_report_load8_noabort+0x14/0x20 [ 27.755818] [] sg_remove_request+0x103/0x120 [ 27.761845] [] sg_finish_rem_req+0x295/0x340 [ 27.767869] [] sg_read+0xa16/0x1440 [ 27.773114] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 27.779745] [] ? fasync_insert_entry+0x147/0x2e0 [ 27.786117] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 27.792751] [] __vfs_read+0x103/0x670 [ 27.798167] [] ? default_llseek+0x290/0x290 [ 27.804106] [] ? fsnotify+0x86/0xf30 [ 27.809434] [] ? fsnotify+0xf30/0xf30 [ 27.814853] [] ? avc_policy_seqno+0x9/0x20 [ 27.820706] [] ? selinux_file_permission+0x82/0x460 [ 27.827338] [] ? security_file_permission+0x89/0x1e0 [ 27.834058] [] ? rw_verify_area+0xe5/0x2b0 [ 27.839908] [] vfs_read+0x11e/0x380 [ 27.845152] [] SyS_read+0xd9/0x1b0 [ 27.850307] [] ? vfs_copy_file_range+0x740/0x740 [ 27.856681] [] ? do_syscall_64+0x48/0x490 [ 27.862453] [] ? vfs_copy_file_range+0x740/0x740 [ 27.868827] [] do_syscall_64+0x1a4/0x490 [ 27.874509] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 27.881887] Dumping ftrace buffer: [ 27.885399] (ftrace buffer empty) [ 27.889086] Kernel Offset: disabled [ 27.892678] Rebooting in 86400 seconds..