[....] Starting enhanced syslogd: rsyslogd[ 13.652724] audit: type=1400 audit(1515773972.976:4): avc: denied { syslog } for pid=3174 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 '10.128.0.57' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 33.727697] ================================================================== [ 33.735110] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 33.742177] Read of size 8 at addr ffff8801c972e140 by task syzkaller211703/3332 [ 33.749672] [ 33.751282] CPU: 0 PID: 3332 Comm: syzkaller211703 Not tainted 4.9.76-g9154940 #20 [ 33.758953] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 33.768278] ffff8801c61cfa50 ffffffff81d93149 ffffea000725cb80 ffff8801c972e140 [ 33.776260] 0000000000000000 ffff8801c972e140 ffff8801c8dc4438 ffff8801c61cfa88 [ 33.784247] ffffffff8153cb43 ffff8801c972e140 0000000000000008 0000000000000000 [ 33.792196] Call Trace: [ 33.794753] [] dump_stack+0xc1/0x128 [ 33.800087] [] print_address_description+0x73/0x280 [ 33.806719] [] kasan_report+0x275/0x360 [ 33.812307] [] ? sg_remove_request+0x103/0x120 [ 33.818508] [] __asan_report_load8_noabort+0x14/0x20 [ 33.825227] [] sg_remove_request+0x103/0x120 [ 33.831250] [] sg_finish_rem_req+0x295/0x340 [ 33.837281] [] sg_read+0xa1c/0x1440 [ 33.842531] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 33.849174] [] ? __raw_spin_lock_init+0x1c/0x100 [ 33.855547] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 33.862353] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 33.869081] [] __vfs_read+0x103/0x670 [ 33.874506] [] ? default_llseek+0x290/0x290 [ 33.880444] [] ? fsnotify+0x86/0xf30 [ 33.885773] [] ? fsnotify+0xf30/0xf30 [ 33.891190] [] ? avc_policy_seqno+0x9/0x20 [ 33.897041] [] ? selinux_file_permission+0x82/0x460 [ 33.903672] [] ? security_file_permission+0x89/0x1e0 [ 33.910388] [] ? rw_verify_area+0xe5/0x2b0 [ 33.916237] [] vfs_read+0x11e/0x380 [ 33.921479] [] SyS_read+0xd9/0x1b0 [ 33.926634] [] ? vfs_copy_file_range+0x740/0x740 [ 33.933007] [] ? do_fast_syscall_32+0xcf/0x890 [ 33.939204] [] ? vfs_copy_file_range+0x740/0x740 [ 33.945578] [] do_fast_syscall_32+0x2f7/0x890 [ 33.951697] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 33.958332] [] entry_SYSENTER_compat+0x74/0x83 [ 33.964525] [ 33.966118] Allocated by task 0: [ 33.969448] (stack is not available) [ 33.973124] [ 33.974716] Freed by task 0: [ 33.977698] (stack is not available) [ 33.981373] [ 33.982968] The buggy address belongs to the object at ffff8801c972e100 [ 33.982968] which belongs to the cache fasync_cache of size 96 [ 33.995591] The buggy address is located 64 bytes inside of [ 33.995591] 96-byte region [ffff8801c972e100, ffff8801c972e160) [ 34.007258] The buggy address belongs to the page: [ 34.012161] page:ffffea000725cb80 count:1 mapcount:0 mapping: (null) index:0x0 [ 34.020384] flags: 0x8000000000000080(slab) [ 34.024668] page dumped because: kasan: bad access detected [ 34.030341] [ 34.031934] Memory state around the buggy address: [ 34.036831] ffff8801c972e000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 34.044155] ffff8801c972e080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 34.051478] >ffff8801c972e100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 34.058801] ^ [ 34.064217] ffff8801c972e180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 34.071541] ffff8801c972e200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 34.078863] ================================================================== [ 34.086185] Disabling lock debugging due to kernel taint [ 34.091889] Kernel panic - not syncing: panic_on_warn set ... [ 34.091889] [ 34.099223] CPU: 0 PID: 3332 Comm: syzkaller211703 Tainted: G B 4.9.76-g9154940 #20 [ 34.108124] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 34.117451] ffff8801c61cf9a8 ffffffff81d93149 ffffffff84195c17 ffff8801c61cfa80 [ 34.125402] 0000000000000000 ffff8801c972e140 ffff8801c8dc4438 ffff8801c61cfa70 [ 34.133353] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 34.141296] Call Trace: [ 34.143854] [] dump_stack+0xc1/0x128 [ 34.149183] [] panic+0x1bc/0x3a8 [ 34.154165] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 34.162362] [] ? preempt_schedule+0x25/0x30 [ 34.168300] [] ? ___preempt_schedule+0x16/0x18 [ 34.174500] [] kasan_end_report+0x50/0x50 [ 34.180261] [] kasan_report+0x167/0x360 [ 34.185850] [] ? sg_remove_request+0x103/0x120 [ 34.192046] [] __asan_report_load8_noabort+0x14/0x20 [ 34.198763] [] sg_remove_request+0x103/0x120 [ 34.204787] [] sg_finish_rem_req+0x295/0x340 [ 34.210810] [] sg_read+0xa1c/0x1440 [ 34.216053] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 34.222685] [] ? __raw_spin_lock_init+0x1c/0x100 [ 34.229057] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 34.235861] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 34.242495] [] __vfs_read+0x103/0x670 [ 34.247911] [] ? default_llseek+0x290/0x290 [ 34.253847] [] ? fsnotify+0x86/0xf30 [ 34.259183] [] ? fsnotify+0xf30/0xf30 [ 34.264604] [] ? avc_policy_seqno+0x9/0x20 [ 34.270456] [] ? selinux_file_permission+0x82/0x460 [ 34.277088] [] ? security_file_permission+0x89/0x1e0 [ 34.283805] [] ? rw_verify_area+0xe5/0x2b0 [ 34.289655] [] vfs_read+0x11e/0x380 [ 34.294895] [] SyS_read+0xd9/0x1b0 [ 34.300064] [] ? vfs_copy_file_range+0x740/0x740 [ 34.306436] [] ? do_fast_syscall_32+0xcf/0x890 [ 34.312643] [] ? vfs_copy_file_range+0x740/0x740 [ 34.319014] [] do_fast_syscall_32+0x2f7/0x890 [ 34.325132] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 34.331766] [] entry_SYSENTER_compat+0x74/0x83 [ 34.338355] Dumping ftrace buffer: [ 34.341860] (ftrace buffer empty) [ 34.345536] Kernel Offset: disabled [ 34.349131] Rebooting in 86400 seconds..