[....] Starting enhanced syslogd: rsyslogd[ 13.064817] audit: type=1400 audit(1515903293.369:4): 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 OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.10' (ECDSA) to the list of known hosts. executing program executing program syzkaller login: [ 24.551305] ================================================================== [ 24.558694] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 24.565855] Read of size 8 at addr ffff8801c859d240 by task syzkaller464606/3335 [ 24.573356] [ 24.574959] CPU: 1 PID: 3335 Comm: syzkaller464606 Not tainted 4.9.76-g8e170a5 #21 [ 24.582664] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.591989] ffff8801c8447a50 ffffffff81d93149 ffffea0007216740 ffff8801c859d240 [ 24.599968] 0000000000000000 ffff8801c859d240 ffff8801c84f4438 ffff8801c8447a88 [ 24.607948] ffffffff8153cb43 ffff8801c859d240 0000000000000008 0000000000000000 [ 24.615926] Call Trace: [ 24.619051] [] dump_stack+0xc1/0x128 [ 24.624390] [] print_address_description+0x73/0x280 [ 24.631026] [] kasan_report+0x275/0x360 [ 24.636620] [] ? sg_remove_request+0x103/0x120 [ 24.642819] [] __asan_report_load8_noabort+0x14/0x20 [ 24.649539] [] sg_remove_request+0x103/0x120 [ 24.655565] [] sg_finish_rem_req+0x295/0x340 [ 24.661589] [] sg_read+0xa1c/0x1440 [ 24.666832] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 24.673470] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 24.680452] [] ? vma_set_page_prot+0x10f/0x180 [ 24.686665] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 24.693300] [] __vfs_read+0x103/0x670 [ 24.698717] [] ? default_llseek+0x290/0x290 [ 24.704655] [] ? fsnotify+0x86/0xf30 [ 24.709987] [] ? fsnotify+0xf30/0xf30 [ 24.715406] [] ? avc_policy_seqno+0x9/0x20 [ 24.721259] [] ? selinux_file_permission+0x82/0x460 [ 24.727892] [] ? security_file_permission+0x89/0x1e0 [ 24.734614] [] ? rw_verify_area+0xe5/0x2b0 [ 24.740464] [] vfs_read+0x11e/0x380 [ 24.745709] [] SyS_read+0xd9/0x1b0 [ 24.750880] [] ? vfs_copy_file_range+0x740/0x740 [ 24.757266] [] ? do_fast_syscall_32+0xcf/0x890 [ 24.763465] [] ? vfs_copy_file_range+0x740/0x740 [ 24.769836] [] do_fast_syscall_32+0x2f7/0x890 [ 24.775953] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 24.782590] [] entry_SYSENTER_compat+0x74/0x83 [ 24.788786] [ 24.790383] Allocated by task 0: [ 24.793713] (stack is not available) [ 24.797391] [ 24.798993] Freed by task 0: [ 24.801975] (stack is not available) [ 24.805662] [ 24.807273] The buggy address belongs to the object at ffff8801c859d200 [ 24.807273] which belongs to the cache fasync_cache of size 96 [ 24.819912] The buggy address is located 64 bytes inside of [ 24.819912] 96-byte region [ffff8801c859d200, ffff8801c859d260) [ 24.831582] The buggy address belongs to the page: [ 24.836481] page:ffffea0007216740 count:1 mapcount:0 mapping: (null) index:0x0 [ 24.844707] flags: 0x8000000000000080(slab) [ 24.849021] page dumped because: kasan: bad access detected [ 24.854702] [ 24.856296] Memory state around the buggy address: [ 24.861194] ffff8801c859d100: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 24.868520] ffff8801c859d180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.875845] >ffff8801c859d200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.883169] ^ [ 24.888585] ffff8801c859d280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc executing program [ 24.895913] ffff8801c859d300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.903236] ================================================================== [ 24.910571] Disabling lock debugging due to kernel taint [ 24.916490] Kernel panic - not syncing: panic_on_warn set ... [ 24.916490] [ 24.923833] CPU: 1 PID: 3335 Comm: syzkaller464606 Tainted: G B 4.9.76-g8e170a5 #21 [ 24.932721] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.942046] ffff8801c84479a8 ffffffff81d93149 ffffffff84195c17 ffff8801c8447a80 [ 24.950014] 0000000000000000 ffff8801c859d240 ffff8801c84f4438 ffff8801c8447a70 [ 24.957984] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 24.965961] Call Trace: [ 24.968526] [] dump_stack+0xc1/0x128 [ 24.973871] [] panic+0x1bc/0x3a8 [ 24.978856] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 24.987056] [] ? preempt_schedule+0x25/0x30 [ 24.993001] [] ? ___preempt_schedule+0x16/0x18 [ 24.999203] [] kasan_end_report+0x50/0x50 [ 25.004969] [] kasan_report+0x167/0x360 [ 25.010566] [] ? sg_remove_request+0x103/0x120 [ 25.017349] [] __asan_report_load8_noabort+0x14/0x20 [ 25.024076] [] sg_remove_request+0x103/0x120 [ 25.030708] [] sg_finish_rem_req+0x295/0x340 [ 25.036736] [] sg_read+0xa1c/0x1440 [ 25.041986] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.048645] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 25.055627] [] ? vma_set_page_prot+0x10f/0x180 [ 25.061858] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.068494] [] __vfs_read+0x103/0x670 [ 25.073914] [] ? default_llseek+0x290/0x290 [ 25.079856] [] ? fsnotify+0x86/0xf30 [ 25.085187] [] ? fsnotify+0xf30/0xf30 [ 25.090607] [] ? avc_policy_seqno+0x9/0x20 [ 25.096460] [] ? selinux_file_permission+0x82/0x460 [ 25.103103] [] ? security_file_permission+0x89/0x1e0 [ 25.109825] [] ? rw_verify_area+0xe5/0x2b0 [ 25.115685] [] vfs_read+0x11e/0x380 [ 25.120930] [] SyS_read+0xd9/0x1b0 [ 25.126086] [] ? vfs_copy_file_range+0x740/0x740 [ 25.132459] [] ? do_fast_syscall_32+0xcf/0x890 [ 25.138660] [] ? vfs_copy_file_range+0x740/0x740 [ 25.145033] [] do_fast_syscall_32+0x2f7/0x890 [ 25.151144] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.157778] [] entry_SYSENTER_compat+0x74/0x83 [ 25.164338] Dumping ftrace buffer: [ 25.167845] (ftrace buffer empty) [ 25.171525] Kernel Offset: disabled [ 25.175123] Rebooting in 86400 seconds..