fix(plugins): add regex length limit#7802
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yongtang merged 1 commit intoJan 5, 2026
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Corefile input containing large regex patterns can trigger large memory allocations during regexp.Compile(). This has resulted in out-of-memory conditions in fuzz tests. Add maxRegexpLen (10000) check before regex compilation in: - plugin/rewrite: name, rcode, ttl, cname_target rules - plugin/template: match clause - plugin/errors: consolidate pattern This follows the existing pattern in plugin/auto/setup.go. Signed-off-by: Ville Vesilehto <ville@vesilehto.fi>
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yongtang
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Jan 5, 2026
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1. Why is this pull request needed and what does it do?
Corefile input containing large regex patterns can trigger large memory allocations during
regexp.Compile(). This has resulted in out-of-memory conditions in fuzz tests.Add
maxRegexpLen(10000) check before regex compilation in:This follows the existing pattern in the auto plugin from #7737.
2. Which issues (if any) are related?
Fixes OSS-Fuzz finding #473316397 (not publicly available yet).
3. Which documentation changes (if any) need to be made?
Updated plugin docs for
rewrite,templateanderrorsplugins.4. Does this introduce a backward incompatible change or deprecation?
No. The limit is supposed to be abundantly high to cover any and all real use cases.