This PR was squashed before being merged into the 2.3 branch (closes#16177).
Discussion
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[HttpFoundation] Fixes /0 subnet handling in IpUtils
| Q | A
| ------------- | ---
| Bug fix? | yes
| New feature? | no
| BC breaks? | no
| Deprecations? | no
| Tests pass? | yes
| Fixed tickets | #16055
| License | MIT
| Doc PR | Not needed
Fixes bug #16055. For IP addresses with CIDR subnet length 0, the IP address must be valid - IPs with subnet masks greater than zero are implicitly validated due to the use of `ip2long` and `substr_compare` (although it's not particularly robust - there could be some future work to improve this here).
Commits
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d9ac571 [HttpFoundation] Fixes /0 subnet handling in IpUtils
