audit: type=1400 audit(1602344812.158:8): avc:  denied  { execmem } for  pid=6344 comm="syz-executor991" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1
==================================================================
BUG: KASAN: slab-out-of-bounds in tipc_nametbl_lookup_dst_nodes+0x44c/0x4c0 net/tipc/name_table.c:670
Read of size 4 at addr ffff88809af06750 by task syz-executor991/6344

CPU: 0 PID: 6344 Comm: syz-executor991 Not tainted 4.14.198-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x283 lib/dump_stack.c:58
 print_address_description.cold+0x54/0x1d3 mm/kasan/report.c:252
 kasan_report_error.cold+0x8a/0x194 mm/kasan/report.c:351
 kasan_report mm/kasan/report.c:409 [inline]
 __asan_report_load4_noabort+0x68/0x70 mm/kasan/report.c:429
 tipc_nametbl_lookup_dst_nodes+0x44c/0x4c0 net/tipc/name_table.c:670
 tipc_sendmcast+0x51a/0xac0 net/tipc/socket.c:767
 __tipc_sendmsg+0xbab/0xf90 net/tipc/socket.c:971
 tipc_sendmsg+0x4c/0x70 net/tipc/socket.c:919
 sock_sendmsg_nosec net/socket.c:646 [inline]
 sock_sendmsg+0xb5/0x100 net/socket.c:656
 ___sys_sendmsg+0x6c8/0x800 net/socket.c:2062
 __sys_sendmsg+0xa3/0x120 net/socket.c:2096
 SYSC_sendmsg net/socket.c:2107 [inline]
 SyS_sendmsg+0x27/0x40 net/socket.c:2103
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x440299
RSP: 002b:00007ffd8cabab98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440299
RDX: 0000000000000000 RSI: 00000000200014c0 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401aa0
R13: 0000000000401b30 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 1:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:551
 __do_kmalloc mm/slab.c:3720 [inline]
 __kmalloc+0x15a/0x400 mm/slab.c:3729
 tipc_nameseq_create+0x53/0x290 net/tipc/name_table.c:152
 tipc_nametbl_insert_publ+0x59b/0x14a0 net/tipc/name_table.c:476
 tipc_nametbl_publish+0x211/0x3f0 net/tipc/name_table.c:701
 tipc_sk_publish net/tipc/socket.c:2206 [inline]
 tipc_bind+0x2c4/0x600 net/tipc/socket.c:629
 tipc_create_listen_sock net/tipc/server.c:338 [inline]
 tipc_open_listening_sock net/tipc/server.c:396 [inline]
 tipc_server_start+0x31f/0x880 net/tipc/server.c:611
 tipc_topsrv_start net/tipc/subscr.c:382 [inline]
 tipc_topsrv_init_net+0x53b/0x730 net/tipc/subscr.c:397
 ops_init+0xaa/0x3e0 net/core/net_namespace.c:118
 __register_pernet_operations net/core/net_namespace.c:881 [inline]
 register_pernet_operations+0x32f/0x750 net/core/net_namespace.c:955
 register_pernet_device+0x28/0x70 net/core/net_namespace.c:1043
 tipc_init+0x7d/0x137 net/tipc/core.c:131
 do_one_initcall+0x88/0x202 init/main.c:826
 do_initcall_level init/main.c:892 [inline]
 do_initcalls init/main.c:900 [inline]
 do_basic_setup init/main.c:918 [inline]
 kernel_init_freeable+0x558/0x619 init/main.c:1075
 kernel_init+0xd/0x15b init/main.c:1000
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404

Freed by task 0:
(stack is not available)

The buggy address belongs to the object at ffff88809af06740
 which belongs to the cache kmalloc-32 of size 32
The buggy address is located 16 bytes inside of
 32-byte region [ffff88809af06740, ffff88809af06760)
The buggy address belongs to the page:
page:ffffea00026bc180 count:1 mapcount:0 mapping:ffff88809af06000 index:0xffff88809af06fc1
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffff88809af06000 ffff88809af06fc1 0000000100000034
raw: ffffea00026c33a0 ffffea0002a95b20 ffff88812fe501c0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88809af06600: 00 00 01 fc fc fc fc fc 00 00 01 fc fc fc fc fc
 ffff88809af06680: 00 01 fc fc fc fc fc fc 00 00 fc fc fc fc fc fc
>ffff88809af06700: 04 fc fc fc fc fc fc fc 00 00 fc fc fc fc fc fc
                                                 ^
 ffff88809af06780: 00 00 01 fc fc fc fc fc 00 00 00 fc fc fc fc fc
 ffff88809af06800: 00 02 fc fc fc fc fc fc 00 00 01 fc fc fc fc fc
==================================================================