Fix multiple prepared stmt registraion #539
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The test simulates the situation when two "parse" packets arrive before their responses, which can cause a data race of pending prepared statements.
It happens twice: after `Parse` and `ParseComplete` packes. Remove the second case.
[skip ci]
Lagovas
reviewed
May 18, 2022
| const sizeLen = 4 | ||
| const nullLen = 1 | ||
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| func writeParsePacket(w io.Writer, name string, stmt string) error { |
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can we use existing logic of encoding statements - https://github.com/cossacklabs/acra/blob/master/decryptor/postgresql/utils.go#L82 ?
My bad, didn't check the last commit.
Lagovas
approved these changes
May 18, 2022
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This PR solves double registration of prepared statements. They are registered twice: after
ParseandParseComplete, but because of a race condition, the pending statement can be replaced by another. Then, this triggers registration of anilvalue as a statement.To solve the problem, this PR removes the second registration.
There is one issue though: prepared statements are never cleaned, even ones that contain errors. This requires a large redesigning of the whole packet processing protocol. So, for now, we have a small memory leakage in a connection. But on practice this should not be an issue.
Checklist
Public API has proper documentation in the Acra documentation site or has PR on documentation repositorywith new changes
CHANGELOG.md is updated (in case of notable or breaking changes)Benchmark results are attached (if applicable)Example projects and code samples are up-to-date (in case of API changes)