[....] Starting enhanced syslogd: rsyslogd[ 11.114176] audit: type=1400 audit(1516090366.580:4): avc: denied { syslog } for pid=3179 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 mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] 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 '10.128.0.20' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 26.893435] ================================================================== [ 26.900814] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 26.907880] Read of size 8 at addr ffff8801cd250140 by task syzkaller547598/3336 [ 26.915377] [ 26.916976] CPU: 1 PID: 3336 Comm: syzkaller547598 Not tainted 4.9.76-g8dec074 #23 [ 26.924649] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.933973] ffff8801caae7a50 ffffffff81d93169 ffffea0007349400 ffff8801cd250140 [ 26.941945] 0000000000000000 ffff8801cd250140 ffff8801ca3ba338 ffff8801caae7a88 [ 26.949900] ffffffff8153cb43 ffff8801cd250140 0000000000000008 0000000000000000 [ 26.957857] Call Trace: [ 26.960413] [] dump_stack+0xc1/0x128 [ 26.965749] [] print_address_description+0x73/0x280 [ 26.972388] [] kasan_report+0x275/0x360 [ 26.977993] [] ? sg_remove_request+0x103/0x120 [ 26.984193] [] __asan_report_load8_noabort+0x14/0x20 [ 26.990915] [] sg_remove_request+0x103/0x120 [ 26.996941] [] sg_finish_rem_req+0x295/0x340 [ 27.002965] [] sg_read+0xa1c/0x1440 [ 27.008207] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 27.014845] [] ? __raw_spin_lock_init+0x1c/0x100 [ 27.021218] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 27.028025] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 27.034663] [] __vfs_read+0x103/0x670 [ 27.040081] [] ? default_llseek+0x290/0x290 [ 27.046017] [] ? fsnotify+0x86/0xf30 [ 27.051345] [] ? fsnotify+0xf30/0xf30 [ 27.056763] [] ? avc_policy_seqno+0x9/0x20 [ 27.062617] [] ? selinux_file_permission+0x82/0x460 [ 27.069252] [] ? security_file_permission+0x89/0x1e0 [ 27.075973] [] ? rw_verify_area+0xe5/0x2b0 [ 27.081824] [] vfs_read+0x11e/0x380 [ 27.087072] [] SyS_read+0xd9/0x1b0 [ 27.092228] [] ? vfs_copy_file_range+0x740/0x740 [ 27.098600] [] ? do_fast_syscall_32+0xcf/0x890 [ 27.104797] [] ? vfs_copy_file_range+0x740/0x740 [ 27.111169] [] do_fast_syscall_32+0x2f7/0x890 [ 27.117281] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.123919] [] entry_SYSENTER_compat+0x74/0x83 [ 27.130114] [ 27.131713] Allocated by task 0: [ 27.135058] (stack is not available) [ 27.138742] [ 27.140336] Freed by task 0: [ 27.143319] (stack is not available) [ 27.146993] [ 27.148590] The buggy address belongs to the object at ffff8801cd250100 [ 27.148590] which belongs to the cache fasync_cache of size 96 [ 27.161211] The buggy address is located 64 bytes inside of [ 27.161211] 96-byte region [ffff8801cd250100, ffff8801cd250160) [ 27.172875] The buggy address belongs to the page: [ 27.177773] page:ffffea0007349400 count:1 mapcount:0 mapping: (null) index:0x0 [ 27.185994] flags: 0x8000000000000080(slab) [ 27.190281] page dumped because: kasan: bad access detected [ 27.195956] [ 27.197551] Memory state around the buggy address: [ 27.202445] ffff8801cd250000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 27.209776] ffff8801cd250080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.217100] >ffff8801cd250100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.224425] ^ [ 27.229843] ffff8801cd250180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.237168] ffff8801cd250200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.244489] ================================================================== [ 27.251814] Disabling lock debugging due to kernel taint [ 27.257612] Kernel panic - not syncing: panic_on_warn set ... [ 27.257612] [ 27.264959] CPU: 1 PID: 3336 Comm: syzkaller547598 Tainted: G B 4.9.76-g8dec074 #23 [ 27.273846] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.283178] ffff8801caae79a8 ffffffff81d93169 ffffffff84195c2f ffff8801caae7a80 [ 27.291162] 0000000000000000 ffff8801cd250140 ffff8801ca3ba338 ffff8801caae7a70 [ 27.299120] ffffffff8142e371 0000000041b58ab3 ffffffff84189690 ffffffff8142e1b5 [ 27.307082] Call Trace: [ 27.309647] [] dump_stack+0xc1/0x128 [ 27.314986] [] panic+0x1bc/0x3a8 [ 27.319974] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 27.328171] [] ? preempt_schedule+0x25/0x30 [ 27.334111] [] ? ___preempt_schedule+0x16/0x18 [ 27.340309] [] kasan_end_report+0x50/0x50 [ 27.346071] [] kasan_report+0x167/0x360 [ 27.351663] [] ? sg_remove_request+0x103/0x120 [ 27.357862] [] __asan_report_load8_noabort+0x14/0x20 [ 27.364983] [] sg_remove_request+0x103/0x120 [ 27.371008] [] sg_finish_rem_req+0x295/0x340 [ 27.377034] [] sg_read+0xa1c/0x1440 [ 27.382284] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 27.388917] [] ? __raw_spin_lock_init+0x1c/0x100 [ 27.395288] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 27.402096] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 27.408727] [] __vfs_read+0x103/0x670 [ 27.414152] [] ? default_llseek+0x290/0x290 [ 27.420090] [] ? fsnotify+0x86/0xf30 [ 27.425421] [] ? fsnotify+0xf30/0xf30 [ 27.430847] [] ? avc_policy_seqno+0x9/0x20 [ 27.436699] [] ? selinux_file_permission+0x82/0x460 [ 27.443331] [] ? security_file_permission+0x89/0x1e0 [ 27.450056] [] ? rw_verify_area+0xe5/0x2b0 [ 27.455910] [] vfs_read+0x11e/0x380 [ 27.461154] [] SyS_read+0xd9/0x1b0 [ 27.466311] [] ? vfs_copy_file_range+0x740/0x740 [ 27.472684] [] ? do_fast_syscall_32+0xcf/0x890 [ 27.478884] [] ? vfs_copy_file_range+0x740/0x740 [ 27.485255] [] do_fast_syscall_32+0x2f7/0x890 [ 27.491369] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.498003] [] entry_SYSENTER_compat+0x74/0x83 [ 27.504634] Dumping ftrace buffer: [ 27.508141] (ftrace buffer empty) [ 27.511820] Kernel Offset: disabled [ 27.515415] Rebooting in 86400 seconds..