[....] Starting enhanced syslogd: rsyslogd[ 10.474811] audit: type=1400 audit(1516204869.578:4): avc: denied { syslog } for pid=3168 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 '10.128.15.240' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 29.408414] ================================================================== [ 29.409468] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 29.410445] Read of size 8 at addr ffff8801c910e140 by task syzkaller500619/3326 [ 29.411456] [ 29.411707] CPU: 0 PID: 3326 Comm: syzkaller500619 Not tainted 4.9.77-g033d019 #24 [ 29.412719] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.413952] ffff8801c7cefa50 ffffffff81d941c9 ffffea0007244380 ffff8801c910e140 [ 29.415114] 0000000000000000 ffff8801c910e140 ffff8801cfd10238 ffff8801c7cefa88 [ 29.416259] ffffffff8153db93 ffff8801c910e140 0000000000000008 0000000000000000 [ 29.417422] Call Trace: [ 29.417780] [] dump_stack+0xc1/0x128 [ 29.418497] [] print_address_description+0x73/0x280 [ 29.419378] [] kasan_report+0x275/0x360 [ 29.420786] [] ? sg_remove_request+0x103/0x120 [ 29.421647] [] __asan_report_load8_noabort+0x14/0x20 [ 29.422580] [] sg_remove_request+0x103/0x120 [ 29.423391] [] sg_finish_rem_req+0x295/0x340 [ 29.424245] [] sg_read+0xa1c/0x1440 [ 29.424977] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 29.425855] [] ? __raw_spin_lock_init+0x1c/0x100 [ 29.426712] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 29.427614] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 29.428494] [] __vfs_read+0x103/0x670 [ 29.430408] [] ? default_llseek+0x290/0x290 [ 29.436348] [] ? fsnotify+0x86/0xf30 [ 29.441680] [] ? fsnotify+0xf30/0xf30 [ 29.447100] [] ? avc_policy_seqno+0x9/0x20 [ 29.452953] [] ? selinux_file_permission+0x82/0x460 [ 29.459589] [] ? security_file_permission+0x89/0x1e0 [ 29.466311] [] ? rw_verify_area+0xe5/0x2b0 [ 29.472163] [] vfs_read+0x11e/0x380 [ 29.477411] [] SyS_read+0xd9/0x1b0 [ 29.482571] [] ? vfs_copy_file_range+0x740/0x740 [ 29.488944] [] ? do_fast_syscall_32+0xcf/0x890 [ 29.495145] [] ? vfs_copy_file_range+0x740/0x740 [ 29.501517] [] do_fast_syscall_32+0x2f7/0x890 [ 29.507633] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.514273] [] entry_SYSENTER_compat+0x74/0x83 [ 29.520469] [ 29.522064] Allocated by task 0: [ 29.525396] (stack is not available) [ 29.530118] [ 29.531714] Freed by task 0: [ 29.534696] (stack is not available) [ 29.538373] [ 29.539972] The buggy address belongs to the object at ffff8801c910e100 [ 29.539972] which belongs to the cache fasync_cache of size 96 [ 29.552594] The buggy address is located 64 bytes inside of [ 29.552594] 96-byte region [ffff8801c910e100, ffff8801c910e160) [ 29.564261] The buggy address belongs to the page: [ 29.569160] page:ffffea0007244380 count:1 mapcount:0 mapping: (null) index:0x0 [ 29.577392] flags: 0x8000000000000080(slab) [ 29.581681] page dumped because: kasan: bad access detected [ 29.587356] [ 29.588958] Memory state around the buggy address: [ 29.593870] ffff8801c910e000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 29.601198] ffff8801c910e080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 29.608530] >ffff8801c910e100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 29.615858] ^ [ 29.621282] ffff8801c910e180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 29.628614] ffff8801c910e200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 29.635942] ================================================================== [ 29.643267] Disabling lock debugging due to kernel taint [ 29.648876] Kernel panic - not syncing: panic_on_warn set ... [ 29.648876] [ 29.656213] CPU: 0 PID: 3326 Comm: syzkaller500619 Tainted: G B 4.9.77-g033d019 #24 [ 29.665102] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.674428] ffff8801c7cef9a8 ffffffff81d941c9 ffffffff841970ff ffff8801c7cefa80 [ 29.682406] 0000000000000000 ffff8801c910e140 ffff8801cfd10238 ffff8801c7cefa70 [ 29.690376] ffffffff8142f3c1 0000000041b58ab3 ffffffff8418ab70 ffffffff8142f205 [ 29.698343] Call Trace: [ 29.700900] [] dump_stack+0xc1/0x128 [ 29.706236] [] panic+0x1bc/0x3a8 [ 29.711223] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 29.719423] [] ? preempt_schedule+0x25/0x30 [ 29.725364] [] ? ___preempt_schedule+0x16/0x18 [ 29.731568] [] kasan_end_report+0x50/0x50 [ 29.737342] [] kasan_report+0x167/0x360 [ 29.743039] [] ? sg_remove_request+0x103/0x120 [ 29.749242] [] __asan_report_load8_noabort+0x14/0x20 [ 29.755965] [] sg_remove_request+0x103/0x120 [ 29.761991] [] sg_finish_rem_req+0x295/0x340 [ 29.768017] [] sg_read+0xa1c/0x1440 [ 29.773261] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 29.779893] [] ? __raw_spin_lock_init+0x1c/0x100 [ 29.786267] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 29.793075] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 29.799713] [] __vfs_read+0x103/0x670 [ 29.805132] [] ? default_llseek+0x290/0x290 [ 29.811074] [] ? fsnotify+0x86/0xf30 [ 29.816403] [] ? fsnotify+0xf30/0xf30 [ 29.821825] [] ? avc_policy_seqno+0x9/0x20 [ 29.827687] [] ? selinux_file_permission+0x82/0x460 [ 29.834322] [] ? security_file_permission+0x89/0x1e0 [ 29.841054] [] ? rw_verify_area+0xe5/0x2b0 [ 29.846905] [] vfs_read+0x11e/0x380 [ 29.852152] [] SyS_read+0xd9/0x1b0 [ 29.857310] [] ? vfs_copy_file_range+0x740/0x740 [ 29.863685] [] ? do_fast_syscall_32+0xcf/0x890 [ 29.869883] [] ? vfs_copy_file_range+0x740/0x740 [ 29.876259] [] do_fast_syscall_32+0x2f7/0x890 [ 29.882372] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.889005] [] entry_SYSENTER_compat+0x74/0x83 [ 29.895587] Dumping ftrace buffer: [ 29.899098] (ftrace buffer empty) [ 29.902778] Kernel Offset: disabled [ 29.906376] Rebooting in 86400 seconds..