[release/7.0-staging] Fix JsonDocument thread safety. #92831
Merged
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Backport of #76716 to release/7.0-staging
/cc @eiriktsarpalis
Customer Impact
Even though the
JsonDocument
/JsonElement
types are documented as immutable/thread safe values, the current implementation suffers from a concurrency bug that can result in incorrect strings being returned when multiple threads attempt to call theGetString()
method on the same document. This can result in nondeterministic bugs including potential privacy or security problems.Testing
Added an OuterLoop test validating the absence of the problem.
Risk
Low. This PR removes the cache that was causing the issue. We have concluded that the removal of the cache should not contribute to any perf regressions in real-life scenaria.
Fix #92808