[....] Starting enhanced syslogd: rsyslogd[ 13.685164] audit: type=1400 audit(1516092218.001:4): avc: denied { syslog } for pid=3177 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 '10.128.0.62' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 25.263375] ================================================================== [ 25.270757] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 25.277828] Read of size 8 at addr ffff8801c90cb140 by task syzkaller984754/3332 [ 25.285329] [ 25.286933] CPU: 0 PID: 3332 Comm: syzkaller984754 Not tainted 4.9.76-g8dec074 #23 [ 25.296433] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.305770] ffff8801c7c1f940 ffffffff81d93169 ffffea00072432c0 ffff8801c90cb140 [ 25.313735] 0000000000000000 ffff8801c90cb140 ffff8801c8d3c438 ffff8801c7c1f978 [ 25.321701] ffffffff8153cb43 ffff8801c90cb140 0000000000000008 0000000000000000 [ 25.329666] Call Trace: [ 25.332228] [] dump_stack+0xc1/0x128 [ 25.337576] [] print_address_description+0x73/0x280 [ 25.344212] [] kasan_report+0x275/0x360 [ 25.349816] [] ? sg_remove_request+0x103/0x120 [ 25.356021] [] __asan_report_load8_noabort+0x14/0x20 [ 25.362745] [] sg_remove_request+0x103/0x120 [ 25.368770] [] sg_finish_rem_req+0x295/0x340 [ 25.375326] [] sg_read+0xa1c/0x1440 [ 25.381876] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.388608] [] ? fsnotify+0xf30/0xf30 [ 25.394032] [] ? avc_policy_seqno+0x9/0x20 [ 25.402331] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 25.409370] [] ? security_file_permission+0x89/0x1e0 [ 25.416093] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.422728] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.429362] [] compat_do_readv_writev+0x522/0x760 [ 25.435825] [] ? do_pwritev+0x1a0/0x1a0 [ 25.441422] [] ? fasync_insert_entry+0x147/0x2e0 [ 25.447796] [] ? dev_seq_stop+0x50/0x50 [ 25.453387] [] ? sg_fasync+0x8d/0xb0 [ 25.458722] [] ? selinux_file_ioctl+0x355/0x530 [ 25.465009] [] ? __pmd_alloc+0x410/0x410 [ 25.470692] [] ? selinux_capable+0x40/0x40 [ 25.476551] [] compat_readv+0xe3/0x150 [ 25.482076] [] do_compat_readv+0xf4/0x1d0 [ 25.487852] [] ? compat_readv+0x150/0x150 [ 25.493623] [] ? compat_SyS_ioctl+0x8c/0x2050 [ 25.499740] [] compat_SyS_readv+0x26/0x30 [ 25.505522] [] ? SyS_pwritev2+0x80/0x80 [ 25.511117] [] do_fast_syscall_32+0x2f7/0x890 [ 25.517233] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.523870] [] entry_SYSENTER_compat+0x74/0x83 [ 25.530069] [ 25.531667] Allocated by task 0: [ 25.534998] (stack is not available) [ 25.538677] [ 25.540270] Freed by task 0: [ 25.543253] (stack is not available) [ 25.546932] [ 25.548532] The buggy address belongs to the object at ffff8801c90cb100 [ 25.548532] which belongs to the cache fasync_cache of size 96 [ 25.561422] The buggy address is located 64 bytes inside of [ 25.561422] 96-byte region [ffff8801c90cb100, ffff8801c90cb160) [ 25.573263] The buggy address belongs to the page: [ 25.578160] page:ffffea00072432c0 count:1 mapcount:0 mapping: (null) index:0x0 [ 25.586387] flags: 0x8000000000000080(slab) [ 25.590941] page dumped because: kasan: bad access detected [ 25.596617] [ 25.598213] Memory state around the buggy address: [ 25.603108] ffff8801c90cb000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 25.610432] ffff8801c90cb080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.617762] >ffff8801c90cb100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.625092] ^ [ 25.630514] ffff8801c90cb180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.637842] ffff8801c90cb200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.645177] ================================================================== [ 25.652501] Disabling lock debugging due to kernel taint [ 25.659773] Kernel panic - not syncing: panic_on_warn set ... [ 25.659773] [ 25.667129] CPU: 0 PID: 3332 Comm: syzkaller984754 Tainted: G B 4.9.76-g8dec074 #23 [ 25.676033] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.685361] ffff8801c7c1f898 ffffffff81d93169 ffffffff84195c2f ffff8801c7c1f970 [ 25.693337] 0000000000000000 ffff8801c90cb140 ffff8801c8d3c438 ffff8801c7c1f960 [ 25.701303] ffffffff8142e371 0000000041b58ab3 ffffffff84189690 ffffffff8142e1b5 [ 25.709272] Call Trace: [ 25.711833] [] dump_stack+0xc1/0x128 [ 25.717170] [] panic+0x1bc/0x3a8 [ 25.722157] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 25.730371] [] ? preempt_schedule+0x25/0x30 [ 25.736318] [] ? ___preempt_schedule+0x16/0x18 [ 25.742529] [] kasan_end_report+0x50/0x50 [ 25.748296] [] kasan_report+0x167/0x360 [ 25.753901] [] ? sg_remove_request+0x103/0x120 [ 25.760103] [] __asan_report_load8_noabort+0x14/0x20 [ 25.767375] [] sg_remove_request+0x103/0x120 [ 25.773407] [] sg_finish_rem_req+0x295/0x340 [ 25.780130] [] sg_read+0xa1c/0x1440 [ 25.785379] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.792014] [] ? fsnotify+0xf30/0xf30 [ 25.797433] [] ? avc_policy_seqno+0x9/0x20 [ 25.803290] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 25.810271] [] ? security_file_permission+0x89/0x1e0 [ 25.816995] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.823630] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.830266] [] compat_do_readv_writev+0x522/0x760 [ 25.836729] [] ? do_pwritev+0x1a0/0x1a0 [ 25.842337] [] ? fasync_insert_entry+0x147/0x2e0 [ 25.848711] [] ? dev_seq_stop+0x50/0x50 [ 25.854310] [] ? sg_fasync+0x8d/0xb0 [ 25.859645] [] ? selinux_file_ioctl+0x355/0x530 [ 25.865935] [] ? __pmd_alloc+0x410/0x410 [ 25.871621] [] ? selinux_capable+0x40/0x40 [ 25.877476] [] compat_readv+0xe3/0x150 [ 25.882984] [] do_compat_readv+0xf4/0x1d0 [ 25.889720] [] ? compat_readv+0x150/0x150 [ 25.895488] [] ? compat_SyS_ioctl+0x8c/0x2050 [ 25.901602] [] compat_SyS_readv+0x26/0x30 [ 25.907373] [] ? SyS_pwritev2+0x80/0x80 [ 25.912970] [] do_fast_syscall_32+0x2f7/0x890 [ 25.919086] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.925722] [] entry_SYSENTER_compat+0x74/0x83 [ 25.932468] Dumping ftrace buffer: [ 25.935976] (ftrace buffer empty) [ 25.939656] Kernel Offset: disabled [ 25.943254] Rebooting in 86400 seconds..