[....] Starting enhanced syslogd: rsyslogd[ 10.245284] audit: type=1400 audit(1516079422.748:4): avc: denied { syslog } for pid=3170 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[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.15.236' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 42.362174] ================================================================== [ 42.363400] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 42.364415] Read of size 8 at addr ffff8801ccb30140 by task syzkaller651242/3342 [ 42.365480] [ 42.365717] CPU: 0 PID: 3342 Comm: syzkaller651242 Not tainted 4.9.76-g8dec074 #13 [ 42.366814] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.368150] ffff8801c7d979b0 ffffffff81d93169 ffffea000732cc00 ffff8801ccb30140 [ 42.369533] 0000000000000000 ffff8801ccb30140 ffff8801c9c3c438 ffff8801c7d979e8 [ 42.370730] ffffffff8153cb43 ffff8801ccb30140 0000000000000008 0000000000000000 [ 42.372041] Call Trace: [ 42.372404] [] dump_stack+0xc1/0x128 [ 42.373160] [] print_address_description+0x73/0x280 [ 42.374070] [] kasan_report+0x275/0x360 [ 42.374864] [] ? sg_remove_request+0x103/0x120 [ 42.375724] [] __asan_report_load8_noabort+0x14/0x20 [ 42.376673] [] sg_remove_request+0x103/0x120 [ 42.377494] [] sg_finish_rem_req+0x295/0x340 [ 42.378297] [] sg_read+0xa1c/0x1440 [ 42.379039] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 42.379983] [] ? fsnotify+0xf30/0xf30 [ 42.380751] [] ? avc_policy_seqno+0x9/0x20 [ 42.381554] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 42.382495] [] ? security_file_permission+0x89/0x1e0 [ 42.389234] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 42.395891] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 42.402584] [] do_readv_writev+0x520/0x750 [ 42.408467] [] ? vfs_write+0x530/0x530 [ 42.413981] [] ? __pmd_alloc+0x410/0x410 [ 42.419665] [] ? dev_seq_stop+0x50/0x50 [ 42.425269] [] ? __do_page_fault+0x5ec/0xd40 [ 42.431325] [] vfs_readv+0x84/0xc0 [ 42.436498] [] do_readv+0xe6/0x250 [ 42.441670] [] ? vfs_readv+0xc0/0xc0 [ 42.447025] [] ? entry_SYSCALL_64_fastpath+0x5/0xe2 [ 42.453671] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 42.460484] [] SyS_readv+0x27/0x30 [ 42.465650] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 42.472207] [ 42.473828] Allocated by task 0: [ 42.477168] (stack is not available) [ 42.480853] [ 42.482455] Freed by task 0: [ 42.485445] (stack is not available) [ 42.489132] [ 42.490735] The buggy address belongs to the object at ffff8801ccb30100 [ 42.490735] which belongs to the cache fasync_cache of size 96 [ 42.503378] The buggy address is located 64 bytes inside of [ 42.503378] 96-byte region [ffff8801ccb30100, ffff8801ccb30160) [ 42.515055] The buggy address belongs to the page: [ 42.519957] page:ffffea000732cc00 count:1 mapcount:0 mapping: (null) index:0x0 [ 42.528207] flags: 0x8000000000000080(slab) [ 42.532514] page dumped because: kasan: bad access detected [ 42.538200] [ 42.539807] Memory state around the buggy address: [ 42.544716] ffff8801ccb30000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 42.552069] ffff8801ccb30080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 42.559402] >ffff8801ccb30100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 42.566731] ^ [ 42.572150] ffff8801ccb30180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 42.579482] ffff8801ccb30200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 42.586831] ================================================================== [ 42.594162] Disabling lock debugging due to kernel taint [ 42.599957] Kernel panic - not syncing: panic_on_warn set ... [ 42.599957] [ 42.607306] CPU: 0 PID: 3342 Comm: syzkaller651242 Tainted: G B 4.9.76-g8dec074 #13 [ 42.616203] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.625540] ffff8801c7d97908 ffffffff81d93169 ffffffff84195c2f ffff8801c7d979e0 [ 42.633514] 0000000000000000 ffff8801ccb30140 ffff8801c9c3c438 ffff8801c7d979d0 [ 42.641486] ffffffff8142e371 0000000041b58ab3 ffffffff84189690 ffffffff8142e1b5 [ 42.649508] Call Trace: [ 42.652087] [] dump_stack+0xc1/0x128 [ 42.657453] [] panic+0x1bc/0x3a8 [ 42.662449] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 42.670654] [] ? preempt_schedule+0x25/0x30 [ 42.676599] [] ? ___preempt_schedule+0x16/0x18 [ 42.682818] [] kasan_end_report+0x50/0x50 [ 42.688614] [] kasan_report+0x167/0x360 [ 42.694236] [] ? sg_remove_request+0x103/0x120 [ 42.700444] [] __asan_report_load8_noabort+0x14/0x20 [ 42.707173] [] sg_remove_request+0x103/0x120 [ 42.713205] [] sg_finish_rem_req+0x295/0x340 [ 42.719256] [] sg_read+0xa1c/0x1440 [ 42.724525] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 42.731170] [] ? fsnotify+0xf30/0xf30 [ 42.736593] [] ? avc_policy_seqno+0x9/0x20 [ 42.742453] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 42.749443] [] ? security_file_permission+0x89/0x1e0 [ 42.756176] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 42.762825] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 42.769471] [] do_readv_writev+0x520/0x750 [ 42.775335] [] ? vfs_write+0x530/0x530 [ 42.780859] [] ? __pmd_alloc+0x410/0x410 [ 42.786542] [] ? dev_seq_stop+0x50/0x50 [ 42.792145] [] ? __do_page_fault+0x5ec/0xd40 [ 42.798177] [] vfs_readv+0x84/0xc0 [ 42.803339] [] do_readv+0xe6/0x250 [ 42.808519] [] ? vfs_readv+0xc0/0xc0 [ 42.813882] [] ? entry_SYSCALL_64_fastpath+0x5/0xe2 [ 42.820532] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 42.827349] [] SyS_readv+0x27/0x30 [ 42.832516] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 42.839500] Dumping ftrace buffer: [ 42.843020] (ftrace buffer empty) [ 42.846709] Kernel Offset: disabled [ 42.850311] Rebooting in 86400 seconds..