[....] Starting enhanced syslogd: rsyslogd[ 13.153223] audit: type=1400 audit(1515675375.899:4): avc: denied { syslog } for pid=3171 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[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.18' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 20.679338] ================================================================== [ 20.686779] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 20.693860] Read of size 8 at addr ffff8801cd9dd140 by task syzkaller773432/3320 [ 20.701359] [ 20.702957] CPU: 0 PID: 3320 Comm: syzkaller773432 Not tainted 4.9.76-g9154940 #10 [ 20.710627] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 20.719950] ffff8801c9e9f9b0 ffffffff81d93149 ffffea0007367740 ffff8801cd9dd140 [ 20.727908] 0000000000000000 ffff8801cd9dd140 ffff8801ca072338 ffff8801c9e9f9e8 [ 20.735874] ffffffff8153cb43 ffff8801cd9dd140 0000000000000008 0000000000000000 [ 20.743841] Call Trace: [ 20.746402] [] dump_stack+0xc1/0x128 [ 20.751736] [] print_address_description+0x73/0x280 [ 20.758370] [] kasan_report+0x275/0x360 [ 20.763961] [] ? sg_remove_request+0x103/0x120 [ 20.770162] [] __asan_report_load8_noabort+0x14/0x20 [ 20.776880] [] sg_remove_request+0x103/0x120 [ 20.782916] [] sg_finish_rem_req+0x295/0x340 [ 20.788951] [] sg_read+0xa1c/0x1440 [ 20.794195] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 20.800839] [] ? fsnotify+0xf30/0xf30 [ 20.806269] [] ? avc_policy_seqno+0x9/0x20 [ 20.812122] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 20.819104] [] ? security_file_permission+0x89/0x1e0 [ 20.825824] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 20.832468] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 20.839111] [] do_readv_writev+0x520/0x750 [ 20.844963] [] ? vfs_write+0x530/0x530 [ 20.850470] [] ? _raw_spin_unlock+0x2c/0x50 [ 20.856409] [] ? __pmd_alloc+0x410/0x410 [ 20.862099] [] ? __do_page_fault+0x5ec/0xd40 [ 20.868136] [] vfs_readv+0x84/0xc0 [ 20.873314] [] do_readv+0xe6/0x250 [ 20.878480] [] ? vfs_readv+0xc0/0xc0 [ 20.883818] [] ? entry_SYSCALL_64_fastpath+0x5/0xe2 [ 20.890454] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 20.897264] [] SyS_readv+0x27/0x30 [ 20.902422] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 20.908965] [ 20.910560] Allocated by task 0: [ 20.913889] (stack is not available) [ 20.917576] [ 20.919172] Freed by task 0: [ 20.922153] (stack is not available) [ 20.925838] [ 20.927440] The buggy address belongs to the object at ffff8801cd9dd100 [ 20.927440] which belongs to the cache fasync_cache of size 96 [ 20.940064] The buggy address is located 64 bytes inside of [ 20.940064] 96-byte region [ffff8801cd9dd100, ffff8801cd9dd160) [ 20.951728] The buggy address belongs to the page: [ 20.956638] page:ffffea0007367740 count:1 mapcount:0 mapping: (null) index:0x0 [ 20.964859] flags: 0x8000000000000080(slab) [ 20.969154] page dumped because: kasan: bad access detected [ 20.974840] [ 20.976431] Memory state around the buggy address: [ 20.981326] ffff8801cd9dd000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 20.988655] ffff8801cd9dd080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 20.995993] >ffff8801cd9dd100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.003327] ^ [ 21.008748] ffff8801cd9dd180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.016074] ffff8801cd9dd200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 21.023406] ================================================================== [ 21.030731] Disabling lock debugging due to kernel taint [ 21.036563] Kernel panic - not syncing: panic_on_warn set ... [ 21.036563] [ 21.043926] CPU: 0 PID: 3320 Comm: syzkaller773432 Tainted: G B 4.9.76-g9154940 #10 [ 21.052817] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 21.062149] ffff8801c9e9f908 ffffffff81d93149 ffffffff84195c17 ffff8801c9e9f9e0 [ 21.070104] 0000000000000000 ffff8801cd9dd140 ffff8801ca072338 ffff8801c9e9f9d0 [ 21.078067] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 21.086040] Call Trace: [ 21.088598] [] dump_stack+0xc1/0x128 [ 21.093931] [] panic+0x1bc/0x3a8 [ 21.098916] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 21.107117] [] ? preempt_schedule+0x25/0x30 [ 21.113059] [] ? ___preempt_schedule+0x16/0x18 [ 21.119259] [] kasan_end_report+0x50/0x50 [ 21.125023] [] kasan_report+0x167/0x360 [ 21.130611] [] ? sg_remove_request+0x103/0x120 [ 21.136810] [] __asan_report_load8_noabort+0x14/0x20 [ 21.143530] [] sg_remove_request+0x103/0x120 [ 21.149554] [] sg_finish_rem_req+0x295/0x340 [ 21.155585] [] sg_read+0xa1c/0x1440 [ 21.160827] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.167475] [] ? fsnotify+0xf30/0xf30 [ 21.172894] [] ? avc_policy_seqno+0x9/0x20 [ 21.178746] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 21.185736] [] ? security_file_permission+0x89/0x1e0 [ 21.192455] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.199086] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 21.205719] [] do_readv_writev+0x520/0x750 [ 21.211571] [] ? vfs_write+0x530/0x530 [ 21.217074] [] ? _raw_spin_unlock+0x2c/0x50 [ 21.223011] [] ? __pmd_alloc+0x410/0x410 [ 21.228702] [] ? __do_page_fault+0x5ec/0xd40 [ 21.234725] [] vfs_readv+0x84/0xc0 [ 21.239879] [] do_readv+0xe6/0x250 [ 21.245036] [] ? vfs_readv+0xc0/0xc0 [ 21.250361] [] ? entry_SYSCALL_64_fastpath+0x5/0xe2 [ 21.257005] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 21.263820] [] SyS_readv+0x27/0x30 [ 21.268974] [] entry_SYSCALL_64_fastpath+0x23/0xe2 [ 21.275984] Dumping ftrace buffer: [ 21.279494] (ftrace buffer empty) [ 21.283179] Kernel Offset: disabled [ 21.286771] Rebooting in 86400 seconds..