[....] Starting enhanced syslogd: rsyslogd[ 12.387820] audit: type=1400 audit(1515870928.756:5): avc: denied { syslog } for pid=3506 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 syzkaller login: [ 18.648501] audit: type=1400 audit(1515870935.017:6): avc: denied { map } for pid=3646 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 Warning: Permanently added '10.128.0.27' (ECDSA) to the list of known hosts. executing program [ 37.278458] audit: type=1400 audit(1515870953.647:7): avc: denied { map } for pid=3663 comm="syzkaller239846" path="/root/syzkaller239846771" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 37.283322] ================================================================== [ 37.283337] BUG: KASAN: use-after-free in rb_first_postorder+0x7c/0xa0 [ 37.283341] Read of size 8 at addr ffff8801d8ff26c0 by task syzkaller239846/3663 [ 37.283342] [ 37.283349] CPU: 1 PID: 3663 Comm: syzkaller239846 Not tainted 4.15.0-rc7-mm1+ #56 [ 37.283351] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 37.283353] Call Trace: [ 37.283362] dump_stack+0x194/0x257 [ 37.283370] ? arch_local_irq_restore+0x53/0x53 [ 37.283376] ? show_regs_print_info+0x18/0x18 [ 37.283386] ? mark_held_locks+0xaf/0x100 [ 37.283391] ? rb_first_postorder+0x7c/0xa0 [ 37.283400] print_address_description+0x73/0x250 [ 37.283404] ? rb_first_postorder+0x7c/0xa0 [ 37.283410] kasan_report+0x23b/0x360 [ 37.283418] __asan_report_load8_noabort+0x14/0x20 [ 37.283422] rb_first_postorder+0x7c/0xa0 [ 37.283431] tipc_group_join+0x120/0x2d0 [ 37.283439] ? tipc_group_update_member+0x740/0x740 [ 37.283442] ? tipc_sk_publish+0x388/0x4b0 [ 37.283457] ? tipc_nametbl_build_group+0x2a0/0x3a0 [ 37.283468] tipc_setsockopt+0x67e/0xcc0 [ 37.283476] ? tipc_sk_leave+0x200/0x200 [ 37.283494] ? security_socket_setsockopt+0x89/0xb0 [ 37.283505] SyS_setsockopt+0x189/0x360 [ 37.283513] ? SyS_recv+0x40/0x40 [ 37.283521] ? entry_SYSCALL_64_fastpath+0x5/0xa0 [ 37.283528] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 37.283535] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 37.283547] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 37.283550] RIP: 0033:0x43fcb9 [ 37.283553] RSP: 002b:00007ffeb1302878 EFLAGS: 00000213 ORIG_RAX: 0000000000000036 [ 37.283558] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fcb9 [ 37.283561] RDX: 0000000000000087 RSI: 000000000000010f RDI: 0000000000000003 [ 37.283563] RBP: 00000000006ca018 R08: 0000000000000010 R09: 0000000000401620 [ 37.283566] R10: 0000000020265000 R11: 0000000000000213 R12: 0000000000401620 [ 37.283568] R13: 00000000004016b0 R14: 0000000000000000 R15: 0000000000000000 [ 37.283585] [ 37.283587] Allocated by task 3663: [ 37.283592] save_stack+0x43/0xd0 [ 37.283595] kasan_kmalloc+0xad/0xe0 [ 37.283599] kmem_cache_alloc_trace+0x136/0x750 [ 37.283602] tipc_group_create+0x144/0x900 [ 37.283605] tipc_setsockopt+0x274/0xcc0 [ 37.283609] SyS_setsockopt+0x189/0x360 [ 37.283612] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 37.283614] [ 37.283615] Freed by task 3663: [ 37.283619] save_stack+0x43/0xd0 [ 37.283622] __kasan_slab_free+0x11a/0x170 [ 37.283626] kasan_slab_free+0xe/0x10 [ 37.283629] kfree+0xd9/0x260 [ 37.283632] tipc_group_delete+0x2c8/0x3d0 [ 37.283635] tipc_setsockopt+0xba3/0xcc0 [ 37.283639] SyS_setsockopt+0x189/0x360 [ 37.283642] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 37.283644] [ 37.283647] The buggy address belongs to the object at ffff8801d8ff26c0 [ 37.283647] which belongs to the cache kmalloc-128 of size 128 [ 37.283650] The buggy address is located 0 bytes inside of [ 37.283650] 128-byte region [ffff8801d8ff26c0, ffff8801d8ff2740) [ 37.283651] The buggy address belongs to the page: [ 37.283656] page:ffffea000763fc80 count:1 mapcount:0 mapping:ffff8801d8ff2000 index:0x0 [ 37.283660] flags: 0x2fffc0000000100(slab) [ 37.283666] raw: 02fffc0000000100 ffff8801d8ff2000 0000000000000000 0000000100000015 [ 37.283670] raw: ffffea0007622fa0 ffff8801dac01548 ffff8801dac00640 0000000000000000 [ 37.283672] page dumped because: kasan: bad access detected [ 37.283673] [ 37.283675] Memory state around the buggy address: [ 37.283678] ffff8801d8ff2580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 37.283681] ffff8801d8ff2600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 37.283684] >ffff8801d8ff2680: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 37.283686] ^ [ 37.283689] ffff8801d8ff2700: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 37.283691] ffff8801d8ff2780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 37.283693] ================================================================== [ 37.283694] Disabling lock debugging due to kernel taint [ 37.283697] Kernel panic - not syncing: panic_on_warn set ... [ 37.283697] [ 37.283700] CPU: 1 PID: 3663 Comm: syzkaller239846 Tainted: G B 4.15.0-rc7-mm1+ #56 [ 37.283702] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 37.283704] Call Trace: [ 37.283708] dump_stack+0x194/0x257 [ 37.283713] ? arch_local_irq_restore+0x53/0x53 [ 37.283717] ? kasan_end_report+0x32/0x50 [ 37.283722] ? lock_downgrade+0x980/0x980 [ 37.283729] ? vsnprintf+0x1ed/0x1900 [ 37.283735] ? rb_next_postorder+0x110/0x140 [ 37.283743] panic+0x1e4/0x41c [ 37.283749] ? refcount_error_report+0x214/0x214 [ 37.283758] ? add_taint+0x40/0x50 [ 37.283762] ? add_taint+0x1c/0x50 [ 37.283769] ? rb_first_postorder+0x7c/0xa0 [ 37.283774] kasan_end_report+0x50/0x50 [ 37.283779] kasan_report+0x148/0x360 [ 37.283786] __asan_report_load8_noabort+0x14/0x20 [ 37.283791] rb_first_postorder+0x7c/0xa0 [ 37.283796] tipc_group_join+0x120/0x2d0 [ 37.283803] ? tipc_group_update_member+0x740/0x740 [ 37.283807] ? tipc_sk_publish+0x388/0x4b0 [ 37.283818] ? tipc_nametbl_build_group+0x2a0/0x3a0 [ 37.283829] tipc_setsockopt+0x67e/0xcc0 [ 37.283836] ? tipc_sk_leave+0x200/0x200 [ 37.283848] ? security_socket_setsockopt+0x89/0xb0 [ 37.283856] SyS_setsockopt+0x189/0x360 [ 37.283864] ? SyS_recv+0x40/0x40 [ 37.283871] ? entry_SYSCALL_64_fastpath+0x5/0xa0 [ 37.283877] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 37.283884] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 37.283894] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 37.283897] RIP: 0033:0x43fcb9 [ 37.283899] RSP: 002b:00007ffeb1302878 EFLAGS: 00000213 ORIG_RAX: 0000000000000036 [ 37.283905] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fcb9 [ 37.283908] RDX: 0000000000000087 RSI: 000000000000010f RDI: 0000000000000003 [ 37.283911] RBP: 00000000006ca018 R08: 0000000000000010 R09: 0000000000401620 [ 37.283913] R10: 0000000020265000 R11: 0000000000000213 R12: 0000000000401620 [ 37.283916] R13: 00000000004016b0 R14: 0000000000000000 R15: 0000000000000000 [ 37.304887] Dumping ftrace buffer: [ 37.304891] (ftrace buffer empty) [ 37.304893] Kernel Offset: disabled [ 37.901430] Rebooting in 86400 seconds..