[ Upstream commitda64ae2d35] Use three-way comparison for address components to avoid integer wraparound in the result of xfrm_policy_addr_delta(). This ensures that the search trees are built and traversed correctly. Treat IPv4 and IPv6 similarly by returning 0 when prefixlen == 0. Prefix /0 has only one equivalence class. Fixes:9cf545ebd5("xfrm: policy: store inexact policies in a tree ordered by destination address") Signed-off-by: Visa Hankala <visa@hankala.org> Acked-by: Florian Westphal <fw@strlen.de> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Sasha Levin <sashal@kernel.org>