netfilter: nft_nat: correct length for loading protocol registers

stable inclusion
from stable-v5.10.176
commit eff050d83eee162a88d52b421f55ea9fad0bb826
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I87BGI

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=eff050d83eee162a88d52b421f55ea9fad0bb826



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[ Upstream commit 068d82e7 ]

The values in the protocol registers are two bytes wide.  However, when
parsing the register loads, the code currently uses the larger 16-byte
size of a `union nf_inet_addr`.  Change it to use the (correct) size of
a `union nf_conntrack_man_proto` instead.

Fixes: d07db988 ("netfilter: nf_tables: introduce nft_validate_register_load()")
Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>