[release/8.0-staging] Workaround bug in EvtFormatMessage #105762
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Backport of #105636 to release/8.0-staging
/cc @ericstj
Customer Impact
Customer reading EventLog records encounters a crash. No way to predict the crash or workaround it (it's an AV, not a managed exception).
Root cause is a misbehaving windows API that writes
\0to a buffer even when it's NULL and zero length. We'll workaround this by giving the API a small buffer to write a single character to.Regression
Regressed in 6.0 with #61990. That change removed the use of StringBuilder, which was previously providing a default buffer of length 16, even when we told the API it was 0 length.
Testing
Manually verified with customer provided data.
Risk
Low - we're adding back a small buffer to receive a copied null value. Should Windows fix this bug in a future version, we'll still be OK with the workaround we've added.