[....] Starting enhanced syslogd: rsyslogd[ 12.716883] audit: type=1400 audit(1516069847.065:4): 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 '10.128.0.49' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 24.320090] ================================================================== [ 24.327483] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 24.334552] Read of size 8 at addr ffff8801c9921140 by task syzkaller408440/3333 [ 24.342056] [ 24.343672] CPU: 0 PID: 3333 Comm: syzkaller408440 Not tainted 4.9.76-g8dec074 #13 [ 24.351350] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.360675] ffff8801cb6979b0 ffffffff81d93169 ffffea0007264840 ffff8801c9921140 [ 24.368673] 0000000000000000 ffff8801c9921140 ffff8801c9f8c438 ffff8801cb6979e8 [ 24.376640] ffffffff8153cb43 ffff8801c9921140 0000000000000008 0000000000000000 [ 24.384615] Call Trace: [ 24.387175] [] dump_stack+0xc1/0x128 [ 24.392507] [] print_address_description+0x73/0x280 [ 24.399141] [] kasan_report+0x275/0x360 [ 24.404745] [] ? sg_remove_request+0x103/0x120 [ 24.410945] [] __asan_report_load8_noabort+0x14/0x20 [ 24.417668] [] sg_remove_request+0x103/0x120 [ 24.423695] [] sg_finish_rem_req+0x295/0x340 [ 24.429721] [] sg_read+0xa1c/0x1440 [ 24.434966] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 24.441599] [] ? fsnotify+0xf30/0xf30 [ 24.447017] [] ? avc_policy_seqno+0x9/0x20 [ 24.452873] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 24.459853] [] ? security_file_permission+0x89/0x1e0 [ 24.466576] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 24.473212] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 24.479845] [] do_readv_writev+0x520/0x750 [ 24.485697] [] ? vfs_write+0x530/0x530 [ 24.491201] [] ? _raw_spin_unlock+0x2c/0x50 [ 24.497139] [] ? fasync_insert_entry+0x147/0x2e0 [ 24.503513] [] ? fasync_helper+0x7a/0xb0 [ 24.509191] [] ? dev_seq_stop+0x50/0x50 [ 24.514786] [] ? selinux_file_ioctl+0x355/0x530 [ 24.521079] [] ? selinux_capable+0x40/0x40 [ 24.526932] [] vfs_readv+0x84/0xc0 [ 24.532088] [] do_readv+0xe6/0x250 [ 24.537260] [] ? vfs_readv+0xc0/0xc0 [ 24.542594] [] ? entry_SYSCALL_64_fastpath+0x5/0xe2 [ 24.549233] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 24.556052] [] SyS_readv+0x27/0x30 [ 24.561220] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 24.567763] [ 24.569358] Allocated by task 0: [ 24.572690] (stack is not available) [ 24.576373] [ 24.577974] Freed by task 0: [ 24.580958] (stack is not available) [ 24.584641] [ 24.586240] The buggy address belongs to the object at ffff8801c9921100 [ 24.586240] which belongs to the cache fasync_cache of size 96 [ 24.598863] The buggy address is located 64 bytes inside of [ 24.598863] 96-byte region [ffff8801c9921100, ffff8801c9921160) [ 24.610532] The buggy address belongs to the page: [ 24.615431] page:ffffea0007264840 count:1 mapcount:0 mapping: (null) index:0x0 [ 24.623658] flags: 0x8000000000000080(slab) [ 24.627945] page dumped because: kasan: bad access detected [ 24.633637] [ 24.635247] Memory state around the buggy address: [ 24.640144] ffff8801c9921000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 24.647476] ffff8801c9921080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.654804] >ffff8801c9921100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.662133] ^ [ 24.667553] ffff8801c9921180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.674881] ffff8801c9921200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.682207] ================================================================== [ 24.689530] Disabling lock debugging due to kernel taint [ 24.695364] Kernel panic - not syncing: panic_on_warn set ... [ 24.695364] [ 24.702723] CPU: 0 PID: 3333 Comm: syzkaller408440 Tainted: G B 4.9.76-g8dec074 #13 [ 24.711633] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.720958] ffff8801cb697908 ffffffff81d93169 ffffffff84195c2f ffff8801cb6979e0 [ 24.728936] 0000000000000000 ffff8801c9921140 ffff8801c9f8c438 ffff8801cb6979d0 [ 24.736896] ffffffff8142e371 0000000041b58ab3 ffffffff84189690 ffffffff8142e1b5 [ 24.744949] Call Trace: [ 24.747509] [] dump_stack+0xc1/0x128 [ 24.752853] [] panic+0x1bc/0x3a8 [ 24.757844] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 24.766042] [] ? preempt_schedule+0x25/0x30 [ 24.771983] [] ? ___preempt_schedule+0x16/0x18 [ 24.778186] [] kasan_end_report+0x50/0x50 [ 24.783952] [] kasan_report+0x167/0x360 [ 24.789545] [] ? sg_remove_request+0x103/0x120 [ 24.795754] [] __asan_report_load8_noabort+0x14/0x20 [ 24.802476] [] sg_remove_request+0x103/0x120 [ 24.808501] [] sg_finish_rem_req+0x295/0x340 [ 24.814525] [] sg_read+0xa1c/0x1440 [ 24.819772] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 24.826414] [] ? fsnotify+0xf30/0xf30 [ 24.831831] [] ? avc_policy_seqno+0x9/0x20 [ 24.837688] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 24.844669] [] ? security_file_permission+0x89/0x1e0 [ 24.851390] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 24.858022] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 24.864657] [] do_readv_writev+0x520/0x750 [ 24.870520] [] ? vfs_write+0x530/0x530 [ 24.876029] [] ? _raw_spin_unlock+0x2c/0x50 [ 24.881968] [] ? fasync_insert_entry+0x147/0x2e0 [ 24.888347] [] ? fasync_helper+0x7a/0xb0 [ 24.894042] [] ? dev_seq_stop+0x50/0x50 [ 24.899642] [] ? selinux_file_ioctl+0x355/0x530 [ 24.905928] [] ? selinux_capable+0x40/0x40 [ 24.911780] [] vfs_readv+0x84/0xc0 [ 24.916940] [] do_readv+0xe6/0x250 [ 24.922098] [] ? vfs_readv+0xc0/0xc0 [ 24.927436] [] ? entry_SYSCALL_64_fastpath+0x5/0xe2 [ 24.934075] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 24.940881] [] SyS_readv+0x27/0x30 [ 24.946038] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 24.953032] Dumping ftrace buffer: [ 24.956547] (ftrace buffer empty) [ 24.960228] Kernel Offset: disabled [ 24.963837] Rebooting in 86400 seconds..