[....] Starting enhanced syslogd: rsyslogd[ 13.140192] audit: type=1400 audit(1517528159.109:4): avc: denied { syslog } for pid=3907 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 '10.128.0.19' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 25.672424] ================================================================== [ 25.679811] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 25.686878] Read of size 8 at addr ffff8801c9349140 by task syzkaller137826/4063 [ 25.694382] [ 25.695983] CPU: 0 PID: 4063 Comm: syzkaller137826 Not tainted 4.9.79-g71f1469 #25 [ 25.703665] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.712990] ffff8801b25bf9b0 ffffffff81d94829 ffffea000724d240 ffff8801c9349140 [ 25.720954] 0000000000000000 ffff8801c9349140 ffff8801d504a338 ffff8801b25bf9e8 [ 25.728913] ffffffff8153e083 ffff8801c9349140 0000000000000008 0000000000000000 [ 25.736873] Call Trace: [ 25.739435] [] dump_stack+0xc1/0x128 [ 25.744770] [] print_address_description+0x73/0x280 [ 25.751403] [] kasan_report+0x275/0x360 [ 25.756993] [] ? sg_remove_request+0x103/0x120 [ 25.763190] [] __asan_report_load8_noabort+0x14/0x20 [ 25.769911] [] sg_remove_request+0x103/0x120 [ 25.775937] [] sg_finish_rem_req+0x295/0x340 [ 25.781971] [] sg_read+0xa16/0x1440 [ 25.787213] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 25.793846] [] ? fsnotify+0xf30/0xf30 [ 25.799264] [] ? avc_policy_seqno+0x9/0x20 [ 25.805119] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 25.812099] [] ? security_file_permission+0x89/0x1e0 [ 25.818825] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 25.825460] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 25.832091] [] do_readv_writev+0x520/0x750 [ 25.837940] [] ? vfs_write+0x530/0x530 [ 25.843446] [] ? __pmd_alloc+0x410/0x410 [ 25.849122] [] ? dev_seq_stop+0x50/0x50 [ 25.854716] [] ? __do_page_fault+0x5ec/0xd40 [ 25.860740] [] vfs_readv+0x84/0xc0 [ 25.865897] [] do_readv+0xe6/0x250 [ 25.871062] [] ? vfs_readv+0xc0/0xc0 [ 25.876392] [] ? entry_SYSCALL_64_fastpath+0x5/0xe8 [ 25.883025] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 25.889829] [] SyS_readv+0x27/0x30 [ 25.894986] [] entry_SYSCALL_64_fastpath+0x29/0xe8 [ 25.901531] [ 25.903128] Allocated by task 0: [ 25.906455] (stack is not available) [ 25.910135] [ 25.911728] Freed by task 0: [ 25.914710] (stack is not available) [ 25.918385] [ 25.919983] The buggy address belongs to the object at ffff8801c9349100 [ 25.919983] which belongs to the cache fasync_cache of size 96 [ 25.932605] The buggy address is located 64 bytes inside of [ 25.932605] 96-byte region [ffff8801c9349100, ffff8801c9349160) [ 25.944272] The buggy address belongs to the page: [ 25.949166] page:ffffea000724d240 count:1 mapcount:0 mapping: (null) index:0x0 [ 25.957391] flags: 0x8000000000000080(slab) [ 25.961677] page dumped because: kasan: bad access detected [ 25.967351] [ 25.968943] Memory state around the buggy address: [ 25.973841] ffff8801c9349000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 25.981171] ffff8801c9349080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.988496] >ffff8801c9349100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.995824] ^ [ 26.001238] ffff8801c9349180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.008564] ffff8801c9349200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.015886] ================================================================== [ 26.023209] Disabling lock debugging due to kernel taint [ 26.028804] Kernel panic - not syncing: panic_on_warn set ... [ 26.028804] [ 26.036138] CPU: 0 PID: 4063 Comm: syzkaller137826 Tainted: G B 4.9.79-g71f1469 #25 [ 26.045025] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.054349] ffff8801b25bf908 ffffffff81d94829 ffffffff8419709f ffff8801b25bf9e0 [ 26.062314] 0000000000000000 ffff8801c9349140 ffff8801d504a338 ffff8801b25bf9d0 [ 26.070278] ffffffff8142f531 0000000041b58ab3 ffffffff8418ab10 ffffffff8142f375 [ 26.078235] Call Trace: [ 26.080793] [] dump_stack+0xc1/0x128 [ 26.086124] [] panic+0x1bc/0x3a8 [ 26.091109] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 26.099307] [] ? preempt_schedule+0x25/0x30 [ 26.105258] [] ? ___preempt_schedule+0x16/0x18 [ 26.111465] [] kasan_end_report+0x50/0x50 [ 26.117229] [] kasan_report+0x167/0x360 [ 26.122820] [] ? sg_remove_request+0x103/0x120 [ 26.129018] [] __asan_report_load8_noabort+0x14/0x20 [ 26.135739] [] sg_remove_request+0x103/0x120 [ 26.141765] [] sg_finish_rem_req+0x295/0x340 [ 26.147795] [] sg_read+0xa16/0x1440 [ 26.153037] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.159673] [] ? fsnotify+0xf30/0xf30 [ 26.165090] [] ? avc_policy_seqno+0x9/0x20 [ 26.170941] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 26.177918] [] ? security_file_permission+0x89/0x1e0 [ 26.184646] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.191279] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.197909] [] do_readv_writev+0x520/0x750 [ 26.203761] [] ? vfs_write+0x530/0x530 [ 26.209263] [] ? __pmd_alloc+0x410/0x410 [ 26.214940] [] ? dev_seq_stop+0x50/0x50 [ 26.220534] [] ? __do_page_fault+0x5ec/0xd40 [ 26.226562] [] vfs_readv+0x84/0xc0 [ 26.231719] [] do_readv+0xe6/0x250 [ 26.236874] [] ? vfs_readv+0xc0/0xc0 [ 26.242204] [] ? entry_SYSCALL_64_fastpath+0x5/0xe8 [ 26.248837] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 26.255647] [] SyS_readv+0x27/0x30 [ 26.260802] [] entry_SYSCALL_64_fastpath+0x29/0xe8 [ 26.267713] Dumping ftrace buffer: [ 26.271220] (ftrace buffer empty) [ 26.274899] Kernel Offset: disabled [ 26.278493] Rebooting in 86400 seconds..