[gabedemesa]

Backport of #67372 to v24.x.

#67372 has not landed yet; this draft is based on its current commit (7288a16) and will be updated with the landed commit, including its PR-URL and Reviewed-By metadata, once it merges.

The cherry-pick conflicted in lib/internal/http2/core.js, because onStreamClose() and closeStream() were restructured on main after v24.x branched. The same changes are applied to the v24.x versions of those functions:

• STREAM_FLAGS_RST_DEFERRED is set where closeStream() defers finishCloseStream to 'finish', and cleared in finishCloseStream().
• Http2Stream#_destroy() submits the deferred RST_STREAM when the stream is already closed with the flag set.
• onStreamClose() clears the flag before destroying. On main this is done only in the locallyInitiated branch; on v24.x it is done unconditionally, which is equivalent because the flag can only be set on a stream that closeStream() has already marked closed.

The src/node_http2.cc change and both tests applied cleanly. Authorship is kept with the original author.

The tests needed one adjustment, in a separate fixup! commit. On main, a stream that receives a clean RST_STREAM before its body ends errors with ERR_HTTP2_STREAM_ABORTED; on v24.x it closes without an error. The tests expected the error, so on v24.x they expect no error on the receiving side instead. Both sides still close with rstCode 0, as the tests assert.

Verification (macOS arm64, local build of this branch)

• test-http2-close-destroy-queued-body and test-http2-server-close-destroy-queued-body pass 50 out of 50 runs each.
• Without the fix (lib/internal/http2/core.js and src/node_http2.cc reverted), both tests run away, reaching 1,756 MB and 1,936 MB of RSS before being stopped.
• parallel/test-http2-* and sequential/test-http2-* pass.
• ESLint and cpplint are clean for the changed files.
• The reproductions from HTTP/2: client session outgoing queue grows without bound (Http2Session::CopyDataIntoOutgoing), OOM-killing the process undici#6181 stay bounded: fetch() uploads aborted mid-body, a server that holds the flow-control window until the client's AbortSignal.timeout() fires, and plain node:http2 close() followed by destroy() (respectively 207 MB, 63 MB, under 1 MB).

🤖 Generated with Claude Code

[nodejs-github-bot]

Review requested:

• @nodejs/http2
• @nodejs/net

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