[....] Starting enhanced syslogd: rsyslogd[ 13.992931] audit: type=1400 audit(1517228503.000:4): avc: denied { syslog } for pid=3808 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 '10.128.0.41' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 26.177640] ================================================================== [ 26.185031] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 26.192114] Read of size 8 at addr ffff8801c19dc140 by task syzkaller552142/3964 [ 26.199620] [ 26.201224] CPU: 1 PID: 3964 Comm: syzkaller552142 Not tainted 4.9.78-g68d447c #23 [ 26.208903] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.218251] ffff8801d5777ab0 ffffffff81d943a9 ffffea0007067700 ffff8801c19dc140 [ 26.226250] 0000000000000000 ffff8801c19dc140 ffff8801d4e50238 ffff8801d5777ae8 [ 26.234228] ffffffff8153dc23 ffff8801c19dc140 0000000000000008 0000000000000000 [ 26.242211] Call Trace: [ 26.244773] [] dump_stack+0xc1/0x128 [ 26.250114] [] print_address_description+0x73/0x280 [ 26.256753] [] kasan_report+0x275/0x360 [ 26.262349] [] ? sg_remove_request+0x103/0x120 [ 26.268553] [] __asan_report_load8_noabort+0x14/0x20 [ 26.275277] [] sg_remove_request+0x103/0x120 [ 26.281314] [] sg_finish_rem_req+0x295/0x340 [ 26.287344] [] sg_read+0xa16/0x1440 [ 26.292591] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.299230] [] ? fasync_insert_entry+0x147/0x2e0 [ 26.305612] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.312271] [] __vfs_read+0x103/0x670 [ 26.317693] [] ? default_llseek+0x290/0x290 [ 26.323637] [] ? fsnotify+0x86/0xf30 [ 26.328970] [] ? fsnotify+0xf30/0xf30 [ 26.334393] [] ? avc_policy_seqno+0x9/0x20 [ 26.340252] [] ? selinux_file_permission+0x82/0x460 [ 26.346901] [] ? security_file_permission+0x89/0x1e0 [ 26.353643] [] ? rw_verify_area+0xe5/0x2b0 [ 26.359503] [] vfs_read+0x11e/0x380 [ 26.364754] [] SyS_read+0xd9/0x1b0 [ 26.369914] [] ? vfs_copy_file_range+0x740/0x740 [ 26.376304] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 26.383118] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.389684] [] entry_SYSCALL_64_fastpath+0x29/0xe8 [ 26.396232] [ 26.397839] Allocated by task 0: [ 26.401173] (stack is not available) [ 26.404854] [ 26.406452] Freed by task 0: [ 26.409438] (stack is not available) [ 26.413120] [ 26.414716] The buggy address belongs to the object at ffff8801c19dc100 [ 26.414716] which belongs to the cache fasync_cache of size 96 [ 26.427343] The buggy address is located 64 bytes inside of [ 26.427343] 96-byte region [ffff8801c19dc100, ffff8801c19dc160) [ 26.439011] The buggy address belongs to the page: [ 26.443913] page:ffffea0007067700 count:1 mapcount:0 mapping: (null) index:0x0 [ 26.452145] flags: 0x8000000000000080(slab) [ 26.456438] page dumped because: kasan: bad access detected [ 26.462134] [ 26.463739] Memory state around the buggy address: [ 26.468642] ffff8801c19dc000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 26.475986] ffff8801c19dc080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.483318] >ffff8801c19dc100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.490648] ^ [ 26.496067] ffff8801c19dc180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.503413] ffff8801c19dc200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.510766] ================================================================== [ 26.518098] Disabling lock debugging due to kernel taint [ 26.523622] Kernel panic - not syncing: panic_on_warn set ... [ 26.523622] [ 26.530981] CPU: 1 PID: 3964 Comm: syzkaller552142 Tainted: G B 4.9.78-g68d447c #23 [ 26.539877] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.549208] ffff8801d5777a08 ffffffff81d943a9 ffffffff841971bf ffff8801d5777ae0 [ 26.557197] 0000000000000000 ffff8801c19dc140 ffff8801d4e50238 ffff8801d5777ad0 [ 26.565194] ffffffff8142f451 0000000041b58ab3 ffffffff8418ac30 ffffffff8142f295 [ 26.573193] Call Trace: [ 26.575767] [] dump_stack+0xc1/0x128 [ 26.581107] [] panic+0x1bc/0x3a8 [ 26.586098] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 26.594304] [] ? preempt_schedule+0x25/0x30 [ 26.600250] [] ? ___preempt_schedule+0x16/0x18 [ 26.606460] [] kasan_end_report+0x50/0x50 [ 26.612235] [] kasan_report+0x167/0x360 [ 26.617835] [] ? sg_remove_request+0x103/0x120 [ 26.624042] [] __asan_report_load8_noabort+0x14/0x20 [ 26.630769] [] sg_remove_request+0x103/0x120 [ 26.636799] [] sg_finish_rem_req+0x295/0x340 [ 26.642831] [] sg_read+0xa16/0x1440 [ 26.648080] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.654721] [] ? fasync_insert_entry+0x147/0x2e0 [ 26.661111] [] ? sg_proc_seq_show_debug+0xd90/0xd90 [ 26.667751] [] __vfs_read+0x103/0x670 [ 26.673174] [] ? default_llseek+0x290/0x290 [ 26.679118] [] ? fsnotify+0x86/0xf30 [ 26.684454] [] ? fsnotify+0xf30/0xf30 [ 26.689875] [] ? avc_policy_seqno+0x9/0x20 [ 26.695730] [] ? selinux_file_permission+0x82/0x460 [ 26.702371] [] ? security_file_permission+0x89/0x1e0 [ 26.709108] [] ? rw_verify_area+0xe5/0x2b0 [ 26.714969] [] vfs_read+0x11e/0x380 [ 26.720220] [] SyS_read+0xd9/0x1b0 [ 26.725386] [] ? vfs_copy_file_range+0x740/0x740 [ 26.731767] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 26.738581] [] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.745143] [] entry_SYSCALL_64_fastpath+0x29/0xe8 [ 26.752282] Dumping ftrace buffer: [ 26.755800] (ftrace buffer empty) [ 26.759483] Kernel Offset: disabled [ 26.763085] Rebooting in 86400 seconds..