[....] Starting enhanced syslogd: rsyslogd[ 12.980760] audit: type=1400 audit(1515938760.454:4): avc: denied { syslog } for pid=3166 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 '10.128.0.15' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 29.801719] ================================================================== [ 29.809112] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0x103/0x120 [ 29.816186] Read of size 8 at addr ffff8801cab1b140 by task syzkaller198995/3325 [ 29.823688] [ 29.825288] CPU: 0 PID: 3325 Comm: syzkaller198995 Not tainted 4.9.76-gf0f6293 #22 [ 29.832973] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.842298] ffff8801cbb57940 ffffffff81d93149 ffffea00072ac6c0 ffff8801cab1b140 [ 29.850278] 0000000000000000 ffff8801cab1b140 ffff8801c8a68238 ffff8801cbb57978 [ 29.858247] ffffffff8153cb43 ffff8801cab1b140 0000000000000008 0000000000000000 [ 29.866219] Call Trace: [ 29.868778] [] dump_stack+0xc1/0x128 [ 29.874122] [] print_address_description+0x73/0x280 [ 29.880759] [] kasan_report+0x275/0x360 [ 29.886354] [] ? sg_remove_request+0x103/0x120 [ 29.892557] [] __asan_report_load8_noabort+0x14/0x20 [ 29.899276] [] sg_remove_request+0x103/0x120 [ 29.905304] [] sg_finish_rem_req+0x295/0x340 [ 29.911332] [] sg_read+0xa1c/0x1440 [ 29.916578] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 29.923219] [] ? fsnotify+0xf30/0xf30 [ 29.928639] [] ? avc_policy_seqno+0x9/0x20 [ 29.934495] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 29.941486] [] ? security_file_permission+0x89/0x1e0 [ 29.948207] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 29.954842] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 29.961478] [] compat_do_readv_writev+0x522/0x760 [ 29.967937] [] ? do_pwritev+0x1a0/0x1a0 [ 29.973537] [] ? _raw_spin_unlock+0x2c/0x50 [ 29.979489] [] ? __pmd_alloc+0x410/0x410 [ 29.985169] [] compat_readv+0xe3/0x150 [ 29.990683] [] do_compat_readv+0xf4/0x1d0 [ 29.996450] [] ? compat_readv+0x150/0x150 [ 30.002221] [] compat_SyS_readv+0x26/0x30 [ 30.007989] [] ? SyS_pwritev2+0x80/0x80 [ 30.013591] [] do_fast_syscall_32+0x2f7/0x890 [ 30.019707] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.026343] [] entry_SYSENTER_compat+0x74/0x83 [ 30.032544] [ 30.034140] Allocated by task 0: [ 30.037475] (stack is not available) [ 30.041158] [ 30.042755] Freed by task 0: [ 30.045745] (stack is not available) [ 30.049424] [ 30.051024] The buggy address belongs to the object at ffff8801cab1b100 [ 30.051024] which belongs to the cache fasync_cache of size 96 [ 30.063649] The buggy address is located 64 bytes inside of [ 30.063649] 96-byte region [ffff8801cab1b100, ffff8801cab1b160) [ 30.075315] The buggy address belongs to the page: [ 30.080214] page:ffffea00072ac6c0 count:1 mapcount:0 mapping: (null) index:0x0 [ 30.088436] flags: 0x8000000000000080(slab) [ 30.092724] page dumped because: kasan: bad access detected [ 30.098410] [ 30.100007] Memory state around the buggy address: [ 30.104903] ffff8801cab1b000: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 30.112234] ffff8801cab1b080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 30.119561] >ffff8801cab1b100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 30.126898] ^ [ 30.132317] ffff8801cab1b180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 30.139653] ffff8801cab1b200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 30.146988] ================================================================== [ 30.154316] Disabling lock debugging due to kernel taint [ 30.159944] Kernel panic - not syncing: panic_on_warn set ... [ 30.159944] [ 30.167286] CPU: 0 PID: 3325 Comm: syzkaller198995 Tainted: G B 4.9.76-gf0f6293 #22 [ 30.176178] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.185505] ffff8801cbb57898 ffffffff81d93149 ffffffff84195c17 ffff8801cbb57970 [ 30.193483] 0000000000000000 ffff8801cab1b140 ffff8801c8a68238 ffff8801cbb57960 [ 30.201454] ffffffff8142e371 0000000041b58ab3 ffffffff84189678 ffffffff8142e1b5 [ 30.209435] Call Trace: [ 30.211996] [] dump_stack+0xc1/0x128 [ 30.217331] [] panic+0x1bc/0x3a8 [ 30.222325] [] ? percpu_up_read_preempt_enable.constprop.53+0xd7/0xd7 [ 30.230526] [] ? preempt_schedule+0x25/0x30 [ 30.236466] [] ? ___preempt_schedule+0x16/0x18 [ 30.242678] [] kasan_end_report+0x50/0x50 [ 30.248444] [] kasan_report+0x167/0x360 [ 30.254040] [] ? sg_remove_request+0x103/0x120 [ 30.260243] [] __asan_report_load8_noabort+0x14/0x20 [ 30.266966] [] sg_remove_request+0x103/0x120 [ 30.272991] [] sg_finish_rem_req+0x295/0x340 [ 30.279025] [] sg_read+0xa1c/0x1440 [ 30.284273] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 30.290908] [] ? fsnotify+0xf30/0xf30 [ 30.296340] [] ? avc_policy_seqno+0x9/0x20 [ 30.302198] [] do_loop_readv_writev.part.17+0x141/0x1e0 [ 30.309182] [] ? security_file_permission+0x89/0x1e0 [ 30.315904] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 30.322540] [] ? sg_proc_seq_show_debug+0xd10/0xd10 [ 30.329176] [] compat_do_readv_writev+0x522/0x760 [ 30.335637] [] ? do_pwritev+0x1a0/0x1a0 [ 30.341234] [] ? _raw_spin_unlock+0x2c/0x50 [ 30.347174] [] ? __pmd_alloc+0x410/0x410 [ 30.352856] [] compat_readv+0xe3/0x150 [ 30.358363] [] do_compat_readv+0xf4/0x1d0 [ 30.364132] [] ? compat_readv+0x150/0x150 [ 30.369899] [] compat_SyS_readv+0x26/0x30 [ 30.375675] [] ? SyS_pwritev2+0x80/0x80 [ 30.381272] [] do_fast_syscall_32+0x2f7/0x890 [ 30.387392] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.394028] [] entry_SYSENTER_compat+0x74/0x83 [ 30.400634] Dumping ftrace buffer: [ 30.404155] (ftrace buffer empty) [ 30.407843] Kernel Offset: disabled [ 30.411449] Rebooting in 86400 seconds..