SELinux: failed to load policy
audit: type=1400 audit(1542557144.131:29): avc:  denied  { associate } for  pid=4948 comm="syz-executor4" name="/" dev="sysfs" ino=1 scontext=system_u:object_r:dhcpc_exec_t:s0 tcontext=system_u:object_r:sysfs_t:s0 tclass=filesystem permissive=1
==================================================================
BUG: KASAN: slab-out-of-bounds in skb_headlen include/linux/skbuff.h:1898 [inline]
BUG: KASAN: slab-out-of-bounds in pskb_may_pull include/linux/skbuff.h:2112 [inline]
BUG: KASAN: slab-out-of-bounds in skb_ensure_writable+0x290/0x2e0 net/core/skbuff.c:5020
Read of size 4 at addr ffff8801c717a9b8 by task syz-executor4/4968

CPU: 0 PID: 4968 Comm: syz-executor4 Not tainted 4.14.81+ #6
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x11b lib/dump_stack.c:53
 print_address_description+0x60/0x22b mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report.cold.6+0x11b/0x2dd mm/kasan/report.c:409
 skb_headlen include/linux/skbuff.h:1898 [inline]
 pskb_may_pull include/linux/skbuff.h:2112 [inline]
 skb_ensure_writable+0x290/0x2e0 net/core/skbuff.c:5020
 __bpf_try_make_writable net/core/filter.c:1403 [inline]
 bpf_try_make_writable net/core/filter.c:1409 [inline]
 ____bpf_l3_csum_replace net/core/filter.c:1530 [inline]
 bpf_l3_csum_replace+0x5f/0x340 net/core/filter.c:1521
 ___bpf_prog_run+0x248e/0x5c70 kernel/bpf/core.c:1012

Allocated by task 3452:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc.part.1+0x4f/0xd0 mm/kasan/kasan.c:551
 slab_post_alloc_hook mm/slab.h:442 [inline]
 slab_alloc_node mm/slub.c:2723 [inline]
 slab_alloc mm/slub.c:2731 [inline]
 kmem_cache_alloc+0xe4/0x2b0 mm/slub.c:2736
 kmem_cache_alloc_node include/linux/slab.h:361 [inline]
 __alloc_skb+0xd8/0x550 net/core/skbuff.c:193
 alloc_skb include/linux/skbuff.h:980 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1158 [inline]
 netlink_sendmsg+0x94b/0xbe0 net/netlink/af_netlink.c:1852
 sock_sendmsg_nosec net/socket.c:645 [inline]
 sock_sendmsg+0xb5/0x100 net/socket.c:655
 SYSC_sendto net/socket.c:1762 [inline]
 SyS_sendto+0x211/0x340 net/socket.c:1730
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Freed by task 3452:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xac/0x190 mm/kasan/kasan.c:524
 slab_free_hook mm/slub.c:1389 [inline]
 slab_free_freelist_hook mm/slub.c:1410 [inline]
 slab_free mm/slub.c:2966 [inline]
 kmem_cache_free+0x12d/0x350 mm/slub.c:2988
 kfree_skbmem+0x9e/0x100 net/core/skbuff.c:582
 __kfree_skb net/core/skbuff.c:642 [inline]
 consume_skb+0xc9/0x330 net/core/skbuff.c:701
 netlink_dump+0x7e5/0xa60 net/netlink/af_netlink.c:2238
 netlink_recvmsg+0xa0c/0xd10 net/netlink/af_netlink.c:1960
 sock_recvmsg_nosec net/socket.c:818 [inline]
 sock_recvmsg+0xc0/0x100 net/socket.c:825
 ___sys_recvmsg+0x242/0x510 net/socket.c:2220
 __sys_recvmsg+0xc7/0x170 net/socket.c:2265
 SYSC_recvmsg net/socket.c:2277 [inline]
 SyS_recvmsg+0x27/0x40 net/socket.c:2272
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

The buggy address belongs to the object at ffff8801c717a8c0
 which belongs to the cache skbuff_head_cache of size 224
The buggy address is located 24 bytes to the right of
 224-byte region [ffff8801c717a8c0, ffff8801c717a9a0)
The buggy address belongs to the page:
page:ffffea00071c5e80 count:1 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000100(slab)
raw: 4000000000000100 0000000000000000 0000000000000000 00000001800c000c
raw: 0000000000000000 0000000100000001 ffff8801d6770200 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c717a880: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff8801c717a900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801c717a980: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
                                        ^
 ffff8801c717aa00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801c717aa80: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
==================================================================