[....] Starting enhanced syslogd: rsyslogd[ 12.740375] audit: type=1400 audit(1515779928.597:4): 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 '10.128.0.29' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 28.331434] ================================================================== [ 28.338819] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 28.345888] Read of size 8 at addr ffff8801c96a0140 by task syzkaller130913/3335 [ 28.353382] [ 28.354979] CPU: 1 PID: 3335 Comm: syzkaller130913 Not tainted 4.9.76-g8e170a5 #21 [ 28.362646] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.371966] ffff8801c82b7a50 ffffffff81d93149 ffffea000725a800 ffff8801c96a0140 [ 28.379913] 0000000000000000 ffff8801c96a0140 ffff8801c8348238 ffff8801c82b7a88 [ 28.387872] ffffffff8153cb43 ffff8801c96a0140 0000000000000008 0000000000000000 [ 28.395821] Call Trace: [ 28.398377] [] dump_stack+0xc1/0x128 [ 28.403707] [] print_address_description+0x73/0x280 [ 28.410348] [] kasan_report+0x275/0x360 [ 28.415936] [] ? sg_remove_request+0x103/0x120 [ 28.422139] [] __asan_report_load8_noabort+0x14/0x20 [ 28.428874] [] sg_remove_request+0x103/0x120 [ 28.434898] [] sg_finish_rem_req+0x295/0x340 [ 28.440920] [] sg_read+0xa1c/0x1440 [ 28.446162] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 28.452794] [] ? __raw_spin_lock_init+0x1c/0x100 [ 28.459166] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.465971] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 28.472602] [] __vfs_read+0x103/0x670 [ 28.478019] [] ? default_llseek+0x290/0x290 [ 28.483953] [] ? fsnotify+0x86/0xf30 [ 28.489282] [] ? fsnotify+0xf30/0xf30 [ 28.494697] [] ? avc_policy_seqno+0x9/0x20 [ 28.500545] [] ? selinux_file_permission+0x82/0x460 [ 28.507175] [] ? security_file_permission+0x89/0x1e0 [ 28.513891] [] ? rw_verify_area+0xe5/0x2b0 [ 28.519749] [] vfs_read+0x11e/0x380 [ 28.524998] [] SyS_read+0xd9/0x1b0 [ 28.530154] [] ? vfs_copy_file_range+0x740/0x740 [ 28.536527] [] ? do_fast_syscall_32+0xcf/0x890 [ 28.542725] [] ? vfs_copy_file_range+0x740/0x740 [ 28.549095] [] do_fast_syscall_32+0x2f7/0x890 [ 28.555204] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 28.561836] [] entry_SYSENTER_compat+0x74/0x83 [ 28.568032] [ 28.569626] Allocated by task 0: [ 28.572955] (stack is not available) [ 28.576629] [ 28.578225] Freed by task 0: [ 28.581205] (stack is not available) [ 28.584879] [ 28.586472] The buggy address belongs to the object at ffff8801c96a0100 [ 28.586472] which belongs to the cache fasync_cache of size 96 [ 28.599092] The buggy address is located 64 bytes inside of [ 28.599092] 96-byte region [ffff8801c96a0100, ffff8801c96a0160) [ 28.610771] The buggy address belongs to the page: [ 28.615672] page:ffffea000725a800 count:1 mapcount:0 mapping: (null) index:0x0 [ 28.623886] flags: 0x8000000000000080(slab) [ 28.628171] page dumped because: kasan: bad access detected [ 28.633840] [ 28.635432] Memory state around the buggy address: [ 28.640323] ffff8801c96a0000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 28.647656] ffff8801c96a0080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 28.654980] >ffff8801c96a0100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 28.662304] ^ [ 28.667727] ffff8801c96a0180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 28.675051] ffff8801c96a0200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 28.682371] ================================================================== [ 28.689701] Disabling lock debugging due to kernel taint [ 28.695408] Kernel panic - not syncing: panic_on_warn set ... [ 28.695408] [ 28.702744] CPU: 1 PID: 3335 Comm: syzkaller130913 Tainted: G B 4.9.76-g8e170a5 #21 [ 28.711632] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.720953] ffff8801c82b79a8 ffffffff81d93149 ffffffff84195c17 ffff8801c82b7a80 [ 28.728899] 0000000000000000 ffff8801c96a0140 ffff8801c8348238 ffff8801c82b7a70 [ 28.736841] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 28.744788] Call Trace: [ 28.747342] [] dump_stack+0xc1/0x128 [ 28.752676] [] panic+0x1bc/0x3a8 [ 28.757662] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 28.765860] [] ? preempt_schedule+0x25/0x30 [ 28.771797] [] ? ___preempt_schedule+0x16/0x18 [ 28.777995] [] kasan_end_report+0x50/0x50 [ 28.783756] [] kasan_report+0x167/0x360 [ 28.789345] [] ? sg_remove_request+0x103/0x120 [ 28.795541] [] __asan_report_load8_noabort+0x14/0x20 [ 28.802259] [] sg_remove_request+0x103/0x120 [ 28.808288] [] sg_finish_rem_req+0x295/0x340 [ 28.814314] [] sg_read+0xa1c/0x1440 [ 28.819558] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 28.826191] [] ? __raw_spin_lock_init+0x1c/0x100 [ 28.832567] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.839398] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 28.846033] [] __vfs_read+0x103/0x670 [ 28.851450] [] ? default_llseek+0x290/0x290 [ 28.857654] [] ? fsnotify+0x86/0xf30 [ 28.862992] [] ? fsnotify+0xf30/0xf30 [ 28.868410] [] ? avc_policy_seqno+0x9/0x20 [ 28.874272] [] ? selinux_file_permission+0x82/0x460 [ 28.880901] [] ? security_file_permission+0x89/0x1e0 [ 28.887622] [] ? rw_verify_area+0xe5/0x2b0 [ 28.893479] [] vfs_read+0x11e/0x380 [ 28.898726] [] SyS_read+0xd9/0x1b0 [ 28.903890] [] ? vfs_copy_file_range+0x740/0x740 [ 28.910272] [] ? do_fast_syscall_32+0xcf/0x890 [ 28.916475] [] ? vfs_copy_file_range+0x740/0x740 [ 28.922846] [] do_fast_syscall_32+0x2f7/0x890 [ 28.928955] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 28.935589] [] entry_SYSENTER_compat+0x74/0x83 [ 28.941824] Dumping ftrace buffer: [ 28.945332] (ftrace buffer empty) [ 28.949017] Kernel Offset: disabled [ 28.952609] Rebooting in 86400 seconds..