[....] Starting enhanced syslogd: rsyslogd[ 15.231716] audit: type=1400 audit(1521621117.114:4): avc: denied { syslog } for pid=3645 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 '10.128.10.6' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 26.612423] ================================================================== [ 26.619841] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 26.626917] Read of size 8 at addr ffff8801c55d2140 by task syzkaller145591/3801 [ 26.634413] [ 26.636012] CPU: 0 PID: 3801 Comm: syzkaller145591 Not tainted 4.9.88-g71df7bb #60 [ 26.643686] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.653009] ffff8801d7477a60 ffffffff81d95f19 ffffea0007157480 ffff8801c55d2140 [ 26.660971] 0000000000000000 ffff8801c55d2140 ffff8801cea7c438 ffff8801d7477a98 [ 26.668929] ffffffff8153e793 ffff8801c55d2140 0000000000000008 0000000000000000 [ 26.676892] Call Trace: [ 26.679451] [] dump_stack+0xc1/0x128 [ 26.684786] [] print_address_description+0x73/0x280 [ 26.691420] [] kasan_report+0x255/0x380 [ 26.697010] [] ? sg_remove_request+0x103/0x120 [ 26.703210] [] __asan_report_load8_noabort+0x14/0x20 [ 26.709928] [] sg_remove_request+0x103/0x120 [ 26.715952] [] sg_finish_rem_req+0x295/0x340 [ 26.721977] [] sg_read+0xa16/0x1440 [ 26.727222] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.733858] [] ? new_slab+0x318/0x420 [ 26.739279] [] ? fasync_helper+0x37/0xb0 [ 26.744957] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.751588] [] __vfs_read+0x103/0x670 [ 26.757005] [] ? default_llseek+0x290/0x290 [ 26.762944] [] ? fsnotify+0x86/0xf30 [ 26.768273] [] ? fsnotify+0xf30/0xf30 [ 26.773693] [] ? avc_policy_seqno+0x9/0x20 [ 26.779542] [] ? selinux_file_permission+0x82/0x460 [ 26.786174] [] ? security_file_permission+0x89/0x1e0 [ 26.792894] [] ? rw_verify_area+0xe5/0x2b0 [ 26.798744] [] vfs_read+0x11e/0x380 [ 26.803988] [] SyS_read+0xd9/0x1b0 [ 26.809145] [] ? vfs_copy_file_range+0x740/0x740 [ 26.815519] [] ? do_syscall_64+0x48/0x490 [ 26.821281] [] ? vfs_copy_file_range+0x740/0x740 [ 26.827653] [] do_syscall_64+0x1a4/0x490 [ 26.833332] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 26.840222] [ 26.841817] Allocated by task 0: [ 26.845147] (stack is not available) [ 26.848825] [ 26.850422] Freed by task 0: [ 26.853405] (stack is not available) [ 26.857084] [ 26.858678] The buggy address belongs to the object at ffff8801c55d2100 [ 26.858678] which belongs to the cache fasync_cache of size 96 [ 26.871301] The buggy address is located 64 bytes inside of [ 26.871301] 96-byte region [ffff8801c55d2100, ffff8801c55d2160) [ 26.882968] The buggy address belongs to the page: [ 26.887866] page:ffffea0007157480 count:1 mapcount:0 mapping: (null) index:0x0 [ 26.896091] flags: 0x8000000000000080(slab) [ 26.900377] page dumped because: kasan: bad access detected [ 26.906050] [ 26.907645] Memory state around the buggy address: [ 26.912541] ffff8801c55d2000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 26.919866] ffff8801c55d2080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.927192] >ffff8801c55d2100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.934516] ^ [ 26.939930] ffff8801c55d2180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.947255] ffff8801c55d2200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.954581] ================================================================== [ 26.961907] Disabling lock debugging due to kernel taint [ 26.967786] Kernel panic - not syncing: panic_on_warn set ... [ 26.967786] [ 26.975138] CPU: 0 PID: 3801 Comm: syzkaller145591 Tainted: G B 4.9.88-g71df7bb #60 [ 26.984026] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.993355] ffff8801d74779b8 ffffffff81d95f19 ffffffff841981e7 ffff8801d7477a90 [ 27.001326] 0000000000000000 ffff8801c55d2140 ffff8801cea7c438 ffff8801d7477a80 [ 27.009299] ffffffff8142fa71 0000000041b58ab3 ffffffff8418bc48 ffffffff8142f8b5 [ 27.017262] Call Trace: [ 27.019828] [] dump_stack+0xc1/0x128 [ 27.025164] [] panic+0x1bc/0x3a8 [ 27.030150] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 27.038351] [] ? preempt_schedule+0x25/0x30 [ 27.044293] [] ? ___preempt_schedule+0x16/0x18 [ 27.050494] [] kasan_end_report+0x50/0x50 [ 27.056260] [] kasan_report+0x16b/0x380 [ 27.061856] [] ? sg_remove_request+0x103/0x120 [ 27.068056] [] __asan_report_load8_noabort+0x14/0x20 [ 27.074777] [] sg_remove_request+0x103/0x120 [ 27.080806] [] sg_finish_rem_req+0x295/0x340 [ 27.086836] [] sg_read+0xa16/0x1440 [ 27.092090] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 27.098723] [] ? new_slab+0x318/0x420 [ 27.104143] [] ? fasync_helper+0x37/0xb0 [ 27.109827] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 27.116461] [] __vfs_read+0x103/0x670 [ 27.121880] [] ? default_llseek+0x290/0x290 [ 27.127824] [] ? fsnotify+0x86/0xf30 [ 27.133153] [] ? fsnotify+0xf30/0xf30 [ 27.138577] [] ? avc_policy_seqno+0x9/0x20 [ 27.144427] [] ? selinux_file_permission+0x82/0x460 [ 27.151061] [] ? security_file_permission+0x89/0x1e0 [ 27.157781] [] ? rw_verify_area+0xe5/0x2b0 [ 27.163636] [] vfs_read+0x11e/0x380 [ 27.168880] [] SyS_read+0xd9/0x1b0 [ 27.174037] [] ? vfs_copy_file_range+0x740/0x740 [ 27.180410] [] ? do_syscall_64+0x48/0x490 [ 27.186178] [] ? vfs_copy_file_range+0x740/0x740 [ 27.192548] [] do_syscall_64+0x1a4/0x490 [ 27.198231] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 27.205471] Dumping ftrace buffer: [ 27.208992] (ftrace buffer empty) [ 27.212670] Kernel Offset: disabled [ 27.216272] Rebooting in 86400 seconds..