This one fell between the cracks, and should have been fixed before -rc5 was released…
………………..
AR net/netfilter/built-in.a
LD [M] net/netfilter/nf_conntrack.o
CC [M] net/netfilter/xt_socket.o
net/netfilter/xt_socket.c: In function ‘socket_mt_destroy’:
net/netfilter/xt_socket.c:224:17: error: implicit declaration of function ‘nf_defrag_ipv6_disable’; did you mean ‘nf_defrag_ipv4_disable’? [-Werror=implicit-function-declaration]
224 | nf_defrag_ipv6_disable(par->net);
| ^~~~~~~~~~~~~~~~~~~~~~
| nf_defrag_ipv4_disable
cc1: some warnings being treated as errors
make[2]: *** [scripts/Makefile.build:288: net/netfilter/xt_socket.o] Error 1
make[1]: *** [scripts/Makefile.build:550: net/netfilter] Error 2
make: *** [Makefile:1831: net] Error 2

The fix was already available, at:   https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf.git/commit/?id=2874b7911132f6975e668f6849c8ac93bc4e1f35

I applied this, and the compile completed successfully..

Also reported on LKML..   http://lkml.iu.edu/hypermail/linux/kernel/2202.2/04703.html

Robert Gadsdon.   February 21st 2022.