[....] Starting enhanced syslogd: rsyslogd[ 10.587751] audit: type=1400 audit(1515500333.595:4): avc: denied { syslog } for pid=3176 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 '10.128.0.16' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 31.066863] ================================================================== [ 31.067960] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 31.069314] Read of size 8 at addr ffff8801c9696140 by task syzkaller239620/3334 [ 31.071260] [ 31.071490] CPU: 1 PID: 3334 Comm: syzkaller239620 Not tainted 4.9.75-gb54d99a #18 [ 31.073225] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.075030] ffff8801c7037a50 ffffffff81d93049 ffffea000725a580 ffff8801c9696140 [ 31.076423] 0000000000000000 ffff8801c9696140 ffff8801c7994438 ffff8801c7037a88 [ 31.078172] ffffffff8153ca53 ffff8801c9696140 0000000000000008 0000000000000000 [ 31.080191] Call Trace: [ 31.080549] [] dump_stack+0xc1/0x128 [ 31.082132] [] print_address_description+0x73/0x280 [ 31.083341] [] kasan_report+0x275/0x360 [ 31.084381] [] ? sg_remove_request+0x103/0x120 [ 31.085252] [] __asan_report_load8_noabort+0x14/0x20 [ 31.086137] [] sg_remove_request+0x103/0x120 [ 31.086936] [] sg_finish_rem_req+0x295/0x340 [ 31.094300] [] sg_read+0xa1c/0x1440 [ 31.100174] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 31.106813] [] ? __raw_spin_lock_init+0x1c/0x100 [ 31.113189] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 31.119999] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 31.126630] [] __vfs_read+0x103/0x670 [ 31.132046] [] ? default_llseek+0x290/0x290 [ 31.137997] [] ? fsnotify+0x86/0xf30 [ 31.143322] [] ? fsnotify+0xf30/0xf30 [ 31.148735] [] ? avc_policy_seqno+0x9/0x20 [ 31.154582] [] ? selinux_file_permission+0x82/0x460 [ 31.161211] [] ? security_file_permission+0x89/0x1e0 [ 31.167926] [] ? rw_verify_area+0xe5/0x2b0 [ 31.173771] [] vfs_read+0x11e/0x380 [ 31.179010] [] SyS_read+0xd9/0x1b0 [ 31.184161] [] ? vfs_copy_file_range+0x740/0x740 [ 31.190538] [] ? do_fast_syscall_32+0xcf/0x890 [ 31.196732] [] ? vfs_copy_file_range+0x740/0x740 [ 31.203456] [] do_fast_syscall_32+0x2f7/0x890 [ 31.209996] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 31.216625] [] entry_SYSENTER_compat+0x74/0x83 [ 31.222832] [ 31.224424] Allocated by task 0: [ 31.227756] (stack is not available) [ 31.231430] [ 31.233019] Freed by task 0: [ 31.235996] (stack is not available) [ 31.239683] [ 31.239686] The buggy address belongs to the object at ffff8801c9696100 [ 31.239686] which belongs to the cache fasync_cache of size 96 [ 31.239689] The buggy address is located 64 bytes inside of [ 31.239689] 96-byte region [ffff8801c9696100, ffff8801c9696160) [ 31.239690] The buggy address belongs to the page: [ 31.239695] page:ffffea000725a580 count:1 mapcount:0 mapping: (null) index:0x0 [ 31.239698] flags: 0x8000000000000080(slab) [ 31.239699] page dumped because: kasan: bad access detected [ 31.239700] [ 31.239701] Memory state around the buggy address: [ 31.239708] ffff8801c9696000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 31.239710] ffff8801c9696080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.239713] >ffff8801c9696100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.239715] ^ [ 31.239717] ffff8801c9696180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.239720] ffff8801c9696200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.239721] ================================================================== [ 31.239722] Disabling lock debugging due to kernel taint [ 31.242165] Kernel panic - not syncing: panic_on_warn set ... [ 31.242165] [ 31.242170] CPU: 1 PID: 3334 Comm: syzkaller239620 Tainted: G B 4.9.75-gb54d99a #18 [ 31.242173] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.242180] ffff8801c70379a8 ffffffff81d93049 ffffffff84195be7 ffff8801c7037a80 [ 31.242185] 0000000000000000 ffff8801c9696140 ffff8801c7994438 ffff8801c7037a70 [ 31.242190] ffffffff8142e281 0000000041b58ab3 ffffffff84189648 ffffffff8142e0c5 [ 31.242191] Call Trace: [ 31.242199] [] dump_stack+0xc1/0x128 [ 31.242206] [] panic+0x1bc/0x3a8 [ 31.242210] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 31.242217] [] ? preempt_schedule+0x25/0x30 [ 31.242222] [] ? ___preempt_schedule+0x16/0x18 [ 31.242228] [] kasan_end_report+0x50/0x50 [ 31.242231] [] kasan_report+0x167/0x360 [ 31.242236] [] ? sg_remove_request+0x103/0x120 [ 31.242240] [] __asan_report_load8_noabort+0x14/0x20 [ 31.242243] [] sg_remove_request+0x103/0x120 [ 31.242247] [] sg_finish_rem_req+0x295/0x340 [ 31.242250] [] sg_read+0xa1c/0x1440 [ 31.242254] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 31.242259] [] ? __raw_spin_lock_init+0x1c/0x100 [ 31.242264] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 31.242267] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 31.242272] [] __vfs_read+0x103/0x670 [ 31.242276] [] ? default_llseek+0x290/0x290 [ 31.242281] [] ? fsnotify+0x86/0xf30 [ 31.242285] [] ? fsnotify+0xf30/0xf30 [ 31.242290] [] ? avc_policy_seqno+0x9/0x20 [ 31.242294] [] ? selinux_file_permission+0x82/0x460 [ 31.242297] [] ? security_file_permission+0x89/0x1e0 [ 31.242301] [] ? rw_verify_area+0xe5/0x2b0 [ 31.242305] [] vfs_read+0x11e/0x380 [ 31.242309] [] SyS_read+0xd9/0x1b0 [ 31.242312] [] ? vfs_copy_file_range+0x740/0x740 [ 31.242316] [] ? do_fast_syscall_32+0xcf/0x890 [ 31.242320] [] ? vfs_copy_file_range+0x740/0x740 [ 31.242323] [] do_fast_syscall_32+0x2f7/0x890 [ 31.242327] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 31.242332] [] entry_SYSENTER_compat+0x74/0x83 [ 31.243045] Dumping ftrace buffer: [ 31.243047] (ftrace buffer empty) [ 31.243049] Kernel Offset: disabled [ 31.608503] Rebooting in 86400 seconds..