[....] Starting enhanced syslogd: rsyslogd[ 13.665485] audit: type=1400 audit(1515263823.087:4): avc: denied { syslog } for pid=3191 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 '10.128.15.239' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 43.241962] ================================================================== [ 43.249363] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 43.256434] Read of size 8 at addr ffff8801c7fe6140 by task syzkaller924044/3356 [ 43.263934] [ 43.265532] CPU: 1 PID: 3356 Comm: syzkaller924044 Not tainted 4.9.75-g06fe41f #16 [ 43.273206] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.282526] ffff8801c7fefa50 ffffffff81d93049 ffffea00071ff980 ffff8801c7fe6140 [ 43.290492] 0000000000000000 ffff8801c7fe6140 ffff8801c8834438 ffff8801c7fefa88 [ 43.298434] ffffffff8153ca53 ffff8801c7fe6140 0000000000000008 0000000000000000 [ 43.306491] Call Trace: [ 43.309044] [] dump_stack+0xc1/0x128 [ 43.314376] [] print_address_description+0x73/0x280 [ 43.321006] [] kasan_report+0x275/0x360 [ 43.326594] [] ? sg_remove_request+0x103/0x120 [ 43.332794] [] __asan_report_load8_noabort+0x14/0x20 [ 43.339521] [] sg_remove_request+0x103/0x120 [ 43.345549] [] sg_finish_rem_req+0x295/0x340 [ 43.351574] [] sg_read+0xa1c/0x1440 [ 43.356831] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 43.363472] [] ? __raw_spin_lock_init+0x1c/0x100 [ 43.369845] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 43.377343] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 43.383975] [] __vfs_read+0x103/0x670 [ 43.389739] [] ? default_llseek+0x290/0x290 [ 43.395674] [] ? fsnotify+0x86/0xf30 [ 43.401001] [] ? fsnotify+0xf30/0xf30 [ 43.406415] [] ? avc_policy_seqno+0x9/0x20 [ 43.412266] [] ? selinux_file_permission+0x82/0x460 [ 43.418904] [] ? security_file_permission+0x89/0x1e0 [ 43.425623] [] ? rw_verify_area+0xe5/0x2b0 [ 43.431482] [] vfs_read+0x11e/0x380 [ 43.436725] [] SyS_read+0xd9/0x1b0 [ 43.441879] [] ? vfs_copy_file_range+0x740/0x740 [ 43.448255] [] ? do_fast_syscall_32+0xcf/0x890 [ 43.454453] [] ? vfs_copy_file_range+0x740/0x740 [ 43.460825] [] do_fast_syscall_32+0x2f7/0x890 [ 43.467021] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 43.473655] [] entry_SYSENTER_compat+0x74/0x83 [ 43.479854] [ 43.481450] Allocated by task 0: [ 43.484778] (stack is not available) [ 43.488452] [ 43.490054] Freed by task 0: [ 43.493037] (stack is not available) [ 43.496710] [ 43.498305] The buggy address belongs to the object at ffff8801c7fe6100 [ 43.498305] which belongs to the cache fasync_cache of size 96 [ 43.510924] The buggy address is located 64 bytes inside of [ 43.510924] 96-byte region [ffff8801c7fe6100, ffff8801c7fe6160) [ 43.522602] The buggy address belongs to the page: [ 43.527505] page:ffffea00071ff980 count:1 mapcount:0 mapping: (null) index:0x0 [ 43.535726] flags: 0x8000000000000080(slab) [ 43.540009] page dumped because: kasan: bad access detected [ 43.545680] [ 43.547272] Memory state around the buggy address: [ 43.552166] ffff8801c7fe6000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 43.559491] ffff8801c7fe6080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 43.566832] >ffff8801c7fe6100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 43.574154] ^ [ 43.579575] ffff8801c7fe6180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 43.586898] ffff8801c7fe6200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 43.594219] ================================================================== [ 43.601540] Disabling lock debugging due to kernel taint [ 43.607157] Kernel panic - not syncing: panic_on_warn set ... [ 43.607157] [ 43.614506] CPU: 1 PID: 3356 Comm: syzkaller924044 Tainted: G B 4.9.75-g06fe41f #16 [ 43.623401] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.632725] ffff8801c7fef9a8 ffffffff81d93049 ffffffff84195be7 ffff8801c7fefa80 [ 43.640690] 0000000000000000 ffff8801c7fe6140 ffff8801c8834438 ffff8801c7fefa70 [ 43.648638] ffffffff8142e281 0000000041b58ab3 ffffffff84189648 ffffffff8142e0c5 [ 43.656581] Call Trace: [ 43.659138] [] dump_stack+0xc1/0x128 [ 43.664468] [] panic+0x1bc/0x3a8 [ 43.669451] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 43.677647] [] ? preempt_schedule+0x25/0x30 [ 43.683589] [] ? ___preempt_schedule+0x16/0x18 [ 43.689799] [] kasan_end_report+0x50/0x50 [ 43.695578] [] kasan_report+0x167/0x360 [ 43.701168] [] ? sg_remove_request+0x103/0x120 [ 43.708590] [] __asan_report_load8_noabort+0x14/0x20 [ 43.715397] [] sg_remove_request+0x103/0x120 [ 43.721425] [] sg_finish_rem_req+0x295/0x340 [ 43.727449] [] sg_read+0xa1c/0x1440 [ 43.732715] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 43.739349] [] ? __raw_spin_lock_init+0x1c/0x100 [ 43.745727] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 43.752539] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 43.759183] [] __vfs_read+0x103/0x670 [ 43.764604] [] ? default_llseek+0x290/0x290 [ 43.770550] [] ? fsnotify+0x86/0xf30 [ 43.775881] [] ? fsnotify+0xf30/0xf30 [ 43.781301] [] ? avc_policy_seqno+0x9/0x20 [ 43.787155] [] ? selinux_file_permission+0x82/0x460 [ 43.793791] [] ? security_file_permission+0x89/0x1e0 [ 43.800519] [] ? rw_verify_area+0xe5/0x2b0 [ 43.806371] [] vfs_read+0x11e/0x380 [ 43.811617] [] SyS_read+0xd9/0x1b0 [ 43.816777] [] ? vfs_copy_file_range+0x740/0x740 [ 43.823158] [] ? do_fast_syscall_32+0xcf/0x890 [ 43.829359] [] ? vfs_copy_file_range+0x740/0x740 [ 43.835735] [] do_fast_syscall_32+0x2f7/0x890 [ 43.841856] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 43.848493] [] entry_SYSENTER_compat+0x74/0x83 [ 43.854741] Dumping ftrace buffer: [ 43.858254] (ftrace buffer empty) [ 43.861941] Kernel Offset: disabled [ 43.865536] Rebooting in 86400 seconds..