netlink: 8 bytes leftover after parsing attributes in process `syz-executor5'.
==================================================================
BUG: KASAN: use-after-free in ____bpf_clone_redirect net/core/filter.c:1767 [inline]
BUG: KASAN: use-after-free in bpf_clone_redirect+0x29a/0x2b0 net/core/filter.c:1758
Read of size 8 at addr ffff8801c5fa7590 by task syz-executor0/7237

CPU: 1 PID: 7237 Comm: syz-executor0 Not tainted 4.14.73+ #12
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
 ____bpf_clone_redirect net/core/filter.c:1767 [inline]
 bpf_clone_redirect+0x29a/0x2b0 net/core/filter.c:1758
 ___bpf_prog_run+0x248e/0x5c70 kernel/bpf/core.c:1012

Allocated by task 7229:
 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
 __build_skb+0x30/0x2c0 net/core/skbuff.c:281
 netlink_alloc_large_skb net/netlink/af_netlink.c:1167 [inline]
 netlink_sendmsg+0x457/0xbe0 net/netlink/af_netlink.c:1852
 sock_sendmsg_nosec net/socket.c:645 [inline]
 sock_sendmsg+0xb5/0x100 net/socket.c:655
 sock_no_sendpage+0x131/0x1a0 net/core/sock.c:2566
 kernel_sendpage+0x80/0xd0 net/socket.c:3409
 sock_sendpage+0x82/0xa0 net/socket.c:870
 pipe_to_sendpage+0x244/0x300 fs/splice.c:451
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x324/0x740 fs/splice.c:626
 splice_from_pipe+0xcf/0x130 fs/splice.c:661
 do_splice_from fs/splice.c:851 [inline]
 direct_splice_actor+0x116/0x160 fs/splice.c:1018
 splice_direct_to_actor+0x28c/0x750 fs/splice.c:973
 do_splice_direct+0x17b/0x220 fs/splice.c:1061
 do_sendfile+0x4a1/0xb50 fs/read_write.c:1438
 SYSC_sendfile64 fs/read_write.c:1493 [inline]
 SyS_sendfile64+0xab/0x140 fs/read_write.c:1485
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Freed by task 7229:
 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_unicast_kernel net/netlink/af_netlink.c:1287 [inline]
 netlink_unicast+0x475/0x620 net/netlink/af_netlink.c:1312
 netlink_sendmsg+0x664/0xbe0 net/netlink/af_netlink.c:1877
 sock_sendmsg_nosec net/socket.c:645 [inline]
 sock_sendmsg+0xb5/0x100 net/socket.c:655
 sock_no_sendpage+0x131/0x1a0 net/core/sock.c:2566
 kernel_sendpage+0x80/0xd0 net/socket.c:3409
 sock_sendpage+0x82/0xa0 net/socket.c:870
 pipe_to_sendpage+0x244/0x300 fs/splice.c:451
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x324/0x740 fs/splice.c:626
 splice_from_pipe+0xcf/0x130 fs/splice.c:661
 do_splice_from fs/splice.c:851 [inline]
 direct_splice_actor+0x116/0x160 fs/splice.c:1018
 splice_direct_to_actor+0x28c/0x750 fs/splice.c:973
 do_splice_direct+0x17b/0x220 fs/splice.c:1061
 do_sendfile+0x4a1/0xb50 fs/read_write.c:1438
 SYSC_sendfile64 fs/read_write.c:1493 [inline]
 SyS_sendfile64+0xab/0x140 fs/read_write.c:1485
 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 ffff8801c5fa7500
 which belongs to the cache skbuff_head_cache of size 224
The buggy address is located 144 bytes inside of
 224-byte region [ffff8801c5fa7500, ffff8801c5fa75e0)
The buggy address belongs to the page:
page:ffffea000717e9c0 count:1 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000100(slab)
raw: 4000000000000100 0000000000000000 0000000000000000 00000001800c000c
raw: ffffea00071f4bc0 0000000800000008 ffff8801dab70200 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c5fa7480: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801c5fa7500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801c5fa7580: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
                         ^
 ffff8801c5fa7600: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff8801c5fa7680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================