[....] Starting enhanced syslogd: rsyslogd[ 13.125998] audit: type=1400 audit(1515539742.291:4): avc: denied { syslog } for pid=3173 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 '10.128.0.54' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 24.499638] ================================================================== [ 24.507023] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 24.514089] Read of size 8 at addr ffff8801c9c97140 by task syzkaller059770/3330 [ 24.521583] [ 24.523180] CPU: 1 PID: 3330 Comm: syzkaller059770 Not tainted 4.9.75-g8910fa5 #19 [ 24.530853] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.540179] ffff8801c95e7a50 ffffffff81d93049 ffffea00072725c0 ffff8801c9c97140 [ 24.548148] 0000000000000000 ffff8801c9c97140 ffff8801c9512338 ffff8801c95e7a88 [ 24.556104] ffffffff8153ca53 ffff8801c9c97140 0000000000000008 0000000000000000 [ 24.564073] Call Trace: [ 24.566629] [] dump_stack+0xc1/0x128 [ 24.572052] [] print_address_description+0x73/0x280 [ 24.578690] [] kasan_report+0x275/0x360 [ 24.584294] [] ? sg_remove_request+0x103/0x120 [ 24.590496] [] __asan_report_load8_noabort+0x14/0x20 [ 24.597219] [] sg_remove_request+0x103/0x120 [ 24.603335] [] sg_finish_rem_req+0x295/0x340 [ 24.609356] [] sg_read+0xa1c/0x1440 [ 24.614599] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 24.621230] [] ? __raw_spin_lock_init+0x1c/0x100 [ 24.627601] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 24.634405] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 24.641036] [] __vfs_read+0x103/0x670 [ 24.646451] [] ? default_llseek+0x290/0x290 [ 24.652389] [] ? fsnotify+0x86/0xf30 [ 24.657718] [] ? fsnotify+0xf30/0xf30 [ 24.663137] [] ? avc_policy_seqno+0x9/0x20 [ 24.669019] [] ? selinux_file_permission+0x82/0x460 [ 24.675661] [] ? security_file_permission+0x89/0x1e0 [ 24.682381] [] ? rw_verify_area+0xe5/0x2b0 [ 24.688331] [] vfs_read+0x11e/0x380 [ 24.693576] [] SyS_read+0xd9/0x1b0 [ 24.698730] [] ? vfs_copy_file_range+0x740/0x740 [ 24.705102] [] ? do_fast_syscall_32+0xcf/0x890 [ 24.711300] [] ? vfs_copy_file_range+0x740/0x740 [ 24.717671] [] do_fast_syscall_32+0x2f7/0x890 [ 24.723783] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 24.730418] [] entry_SYSENTER_compat+0x74/0x83 [ 24.737290] [ 24.738886] Allocated by task 0: [ 24.742219] (stack is not available) [ 24.745894] [ 24.747484] Freed by task 0: [ 24.750463] (stack is not available) [ 24.754137] [ 24.755734] The buggy address belongs to the object at ffff8801c9c97100 [ 24.755734] which belongs to the cache fasync_cache of size 96 [ 24.768353] The buggy address is located 64 bytes inside of [ 24.768353] 96-byte region [ffff8801c9c97100, ffff8801c9c97160) [ 24.780031] The buggy address belongs to the page: [ 24.784982] page:ffffea00072725c0 count:1 mapcount:0 mapping: (null) index:0x0 [ 24.793229] flags: 0x8000000000000080(slab) [ 24.797516] page dumped because: kasan: bad access detected [ 24.803192] [ 24.804803] Memory state around the buggy address: [ 24.809698] ffff8801c9c97000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 24.817026] ffff8801c9c97080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.824355] >ffff8801c9c97100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.831681] ^ [ 24.837095] ffff8801c9c97180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.844429] ffff8801c9c97200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 24.851759] ================================================================== [ 24.859083] Disabling lock debugging due to kernel taint [ 24.864828] Kernel panic - not syncing: panic_on_warn set ... [ 24.864828] [ 24.872163] CPU: 1 PID: 3330 Comm: syzkaller059770 Tainted: G B 4.9.75-g8910fa5 #19 [ 24.881053] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.890376] ffff8801c95e79a8 ffffffff81d93049 ffffffff84195be7 ffff8801c95e7a80 [ 24.898324] 0000000000000000 ffff8801c9c97140 ffff8801c9512338 ffff8801c95e7a70 [ 24.906278] ffffffff8142e281 0000000041b58ab3 ffffffff84189648 ffffffff8142e0c5 [ 24.914223] Call Trace: [ 24.916777] [] dump_stack+0xc1/0x128 [ 24.922115] [] panic+0x1bc/0x3a8 [ 24.927106] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 24.935300] [] ? preempt_schedule+0x25/0x30 [ 24.941238] [] ? ___preempt_schedule+0x16/0x18 [ 24.947441] [] kasan_end_report+0x50/0x50 [ 24.953207] [] kasan_report+0x167/0x360 [ 24.958797] [] ? sg_remove_request+0x103/0x120 [ 24.965000] [] __asan_report_load8_noabort+0x14/0x20 [ 24.971724] [] sg_remove_request+0x103/0x120 [ 24.977748] [] sg_finish_rem_req+0x295/0x340 [ 24.983788] [] sg_read+0xa1c/0x1440 [ 24.989042] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 24.995672] [] ? __raw_spin_lock_init+0x1c/0x100 [ 25.002040] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 25.008846] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 25.015477] [] __vfs_read+0x103/0x670 [ 25.020892] [] ? default_llseek+0x290/0x290 [ 25.026839] [] ? fsnotify+0x86/0xf30 [ 25.032171] [] ? fsnotify+0xf30/0xf30 [ 25.037599] [] ? avc_policy_seqno+0x9/0x20 [ 25.043467] [] ? selinux_file_permission+0x82/0x460 [ 25.050100] [] ? security_file_permission+0x89/0x1e0 [ 25.056829] [] ? rw_verify_area+0xe5/0x2b0 [ 25.062676] [] vfs_read+0x11e/0x380 [ 25.068019] [] SyS_read+0xd9/0x1b0 [ 25.073172] [] ? vfs_copy_file_range+0x740/0x740 [ 25.079555] [] ? do_fast_syscall_32+0xcf/0x890 [ 25.085758] [] ? vfs_copy_file_range+0x740/0x740 [ 25.092226] [] do_fast_syscall_32+0x2f7/0x890 [ 25.098344] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.104983] [] entry_SYSENTER_compat+0x74/0x83 [ 25.111227] Dumping ftrace buffer: [ 25.114735] (ftrace buffer empty) [ 25.118412] Kernel Offset: disabled [ 25.122003] Rebooting in 86400 seconds..