[....] Starting enhanced syslogd: rsyslogd[ 10.780417] audit: type=1400 audit(1515986744.185:4): avc: denied { syslog } for pid=3183 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 '10.128.0.36' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 27.501233] ================================================================== [ 27.502377] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 27.503346] Read of size 8 at addr ffff8801ca900140 by task syzkaller122321/3340 [ 27.504339] [ 27.504569] CPU: 1 PID: 3340 Comm: syzkaller122321 Not tainted 4.9.76-gf0f6293 #22 [ 27.505574] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.506828] ffff8801c7f07940 ffffffff81d93149 ffffea00072a4000 ffff8801ca900140 [ 27.507993] 0000000000000000 ffff8801ca900140 ffff8801c7ff8238 ffff8801c7f07978 [ 27.509142] ffffffff8153cb43 ffff8801ca900140 0000000000000008 0000000000000000 [ 27.510471] Call Trace: [ 27.510870] [] dump_stack+0xc1/0x128 [ 27.511601] [] print_address_description+0x73/0x280 [ 27.512475] [] kasan_report+0x275/0x360 [ 27.513218] [] ? sg_remove_request+0x103/0x120 [ 27.514081] [] __asan_report_load8_noabort+0x14/0x20 [ 27.514970] [] sg_remove_request+0x103/0x120 [ 27.515777] [] sg_finish_rem_req+0x295/0x340 [ 27.516574] [] sg_read+0xa1c/0x1440 [ 27.517275] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 27.518160] [] ? fsnotify+0xf30/0xf30 [ 27.518881] [] ? avc_policy_seqno+0x9/0x20 [ 27.519669] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 27.520590] [] ? security_file_permission+0x89/0x1e0 [ 27.521529] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 27.528168] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 27.534798] [] compat_do_readv_writev+0x522/0x760 [ 27.541255] [] ? do_pwritev+0x1a0/0x1a0 [ 27.546848] [] ? _raw_spin_unlock+0x2c/0x50 [ 27.552785] [] ? handle_mm_fault+0x6ee/0x2530 [ 27.558894] [] ? __pmd_alloc+0x410/0x410 [ 27.564589] [] compat_readv+0xe3/0x150 [ 27.570103] [] do_compat_readv+0xf4/0x1d0 [ 27.575866] [] ? compat_readv+0x150/0x150 [ 27.581630] [] compat_SyS_readv+0x26/0x30 [ 27.587391] [] ? SyS_pwritev2+0x80/0x80 [ 27.592980] [] do_fast_syscall_32+0x2f7/0x890 [ 27.599099] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.605743] [] entry_SYSENTER_compat+0x74/0x83 [ 27.611939] [ 27.613533] Allocated by task 0: [ 27.616862] (stack is not available) [ 27.620541] [ 27.622140] Freed by task 0: [ 27.625119] (stack is not available) [ 27.628799] [ 27.630394] The buggy address belongs to the object at ffff8801ca900100 [ 27.630394] which belongs to the cache fasync_cache of size 96 [ 27.643015] The buggy address is located 64 bytes inside of [ 27.643015] 96-byte region [ffff8801ca900100, ffff8801ca900160) [ 27.654679] The buggy address belongs to the page: [ 27.659578] page:ffffea00072a4000 count:1 mapcount:0 mapping: (null) index:0x0 [ 27.667800] flags: 0x8000000000000080(slab) [ 27.672085] page dumped because: kasan: bad access detected [ 27.677756] [ 27.679346] Memory state around the buggy address: [ 27.684239] ffff8801ca900000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 27.691562] ffff8801ca900080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.698885] >ffff8801ca900100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.706216] ^ [ 27.711631] ffff8801ca900180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.718955] ffff8801ca900200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.726282] ================================================================== [ 27.733610] Disabling lock debugging due to kernel taint [ 27.739276] Kernel panic - not syncing: panic_on_warn set ... [ 27.739276] [ 27.746614] CPU: 1 PID: 3340 Comm: syzkaller122321 Tainted: G B 4.9.76-gf0f6293 #22 [ 27.755501] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.764825] ffff8801c7f07898 ffffffff81d93149 ffffffff84195c17 ffff8801c7f07970 [ 27.772779] 0000000000000000 ffff8801ca900140 ffff8801c7ff8238 ffff8801c7f07960 [ 27.780731] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 27.788698] Call Trace: [ 27.791254] [] dump_stack+0xc1/0x128 [ 27.796586] [] panic+0x1bc/0x3a8 [ 27.801588] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 27.809785] [] ? preempt_schedule+0x25/0x30 [ 27.815744] [] ? ___preempt_schedule+0x16/0x18 [ 27.821951] [] kasan_end_report+0x50/0x50 [ 27.827713] [] kasan_report+0x167/0x360 [ 27.833307] [] ? sg_remove_request+0x103/0x120 [ 27.839506] [] __asan_report_load8_noabort+0x14/0x20 [ 27.846222] [] sg_remove_request+0x103/0x120 [ 27.852259] [] sg_finish_rem_req+0x295/0x340 [ 27.858291] [] sg_read+0xa1c/0x1440 [ 27.863558] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 27.870191] [] ? fsnotify+0xf30/0xf30 [ 27.875608] [] ? avc_policy_seqno+0x9/0x20 [ 27.881459] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 27.888439] [] ? security_file_permission+0x89/0x1e0 [ 27.895164] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 27.901909] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 27.908541] [] compat_do_readv_writev+0x522/0x760 [ 27.915017] [] ? do_pwritev+0x1a0/0x1a0 [ 27.920614] [] ? _raw_spin_unlock+0x2c/0x50 [ 27.926550] [] ? handle_mm_fault+0x6ee/0x2530 [ 27.932671] [] ? __pmd_alloc+0x410/0x410 [ 27.938347] [] compat_readv+0xe3/0x150 [ 27.943848] [] do_compat_readv+0xf4/0x1d0 [ 27.949619] [] ? compat_readv+0x150/0x150 [ 27.955382] [] compat_SyS_readv+0x26/0x30 [ 27.961152] [] ? SyS_pwritev2+0x80/0x80 [ 27.966741] [] do_fast_syscall_32+0x2f7/0x890 [ 27.972852] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.979500] [] entry_SYSENTER_compat+0x74/0x83 [ 27.986091] Dumping ftrace buffer: [ 27.989598] (ftrace buffer empty) [ 27.993275] Kernel Offset: disabled [ 27.996868] Rebooting in 86400 seconds..