Patch fluent-bit for CVE-2026-33630 [HIGH]

[Sumit Jena (SumitJenaHCL)]

Merge Checklist

All boxes should be checked before merging the PR (just tick any boxes which don't apply to this PR)

• The toolchain has been rebuilt successfully (or no changes were made to it)
• The toolchain/worker package manifests are up-to-date
• Any updated packages successfully build (or no packages were changed)
• Packages depending on static components modified in this PR (Golang, *-static subpackages, etc.) have had their Release tag incremented.
• Package tests (%check section) have been verified with RUN_CHECK=y for existing SPEC files, or added to new SPEC files
• All package sources are available
• cgmanifest files are up-to-date and sorted (./cgmanifest.json, ./toolkit/scripts/toolchain/cgmanifest.json, .github/workflows/cgmanifest.json)
• LICENSE-MAP files are up-to-date (./LICENSES-AND-NOTICES/SPECS/data/licenses.json, ./LICENSES-AND-NOTICES/SPECS/LICENSES-MAP.md, ./LICENSES-AND-NOTICES/SPECS/LICENSE-EXCEPTIONS.PHOTON)
• All source files have up-to-date hashes in the *.signatures.json files
• sudo make go-tidy-all and sudo make go-test-coverage pass
• Documentation has been updated to match any changes to the build system
• Ready to merge

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Summary

What does the PR accomplish, why was it needed?

• Fixes CVE-2026-33630 / GHSA-6wfj-rwm7-3542, a double-free in the c-ares copy bundled in fluent-bit (lib/c-ares-1.33.1).
• Query callbacks were invoked while the query was still linked into channel->queries_by_qid and channel->all_queries. Calling ares_cancel() from inside a callback therefore freed the query, and the caller then freed it a second time.
• The upstream fix targets the c-ares 1.34 branch and does not apply to the bundled 1.33.1 tree: 1.34 renamed the internal API (ares_array_t vs. ares__array_t), unified read_tcp_data()/read_udp_packets_fd() into a single read_answers(), and added a requested_server argument to ares_send_query() that does not exist in 1.33.1. The upstream commit has therefore been backported in full and adapted, rather than applied verbatim.

Change Log

• Added SPECS/fluent-bit/CVE-2026-33630.patch, a full backport of upstream c-ares commit d823199b, adapted to the bundled 1.33.1 tree:
  • ares_flush_requeue() — a single shared, iterative drain for the deferred requeue/endqueue list that every flush site now funnels through. It detaches each query from all lookup lists before invoking its callback (the CVE-2026-33630 fix), and re-dispatches retries by appending back onto the same list instead of recursing (upstream issue populate user's ssh/authorized_keys #1043).
  • ares__send_query() split into a public wrapper that owns a requeue list and drains it, plus ares__send_query_int() which defers retries and end-queries onto the caller's list. The wrapper re-checks queries_by_qid before reporting success, since a deferred retry may have terminally failed and freed the query during the drain.
  • process_timeouts() and both read paths now defer through the shared drain. read_udp_packets_fd() previously ignored entry.type and re-sent REQUEUE_ENDQUERY entries instead of completing them; routing it through ares_flush_requeue() corrects that as well.
  • end_query() also detaches on its remaining inline path, which is still reachable via ares__requeue_query() from ares__close_connection().
  • Both upstream regression tests were carried across into test/ares-test-mock.cc: MockUDPChannelTest.CancelInCallbackNoDoubleFree and MockRetryDepthChannelTest.HighRetryNoStackOverflow.
• SPECS/fluent-bit/fluent-bit.spec: added Patch14, incremented Release 6 → 7, added a changelog entry.

Does this affect the toolchain?

NO

Associated issues

• N/A

Links to CVEs

• https://nvd.nist.gov/vuln/detail/CVE-2026-33630
• GHSA-6wfj-rwm7-3542
• Upstream fix: c-ares/c-ares@d823199

Test Methodology

• Local Build
• Pipeline build : https://dev.azure.com/mariner-org/mariner/_build/results?buildId=1199664&view=results

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[Sumit Jena (SumitJenaHCL)]

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