fix: data race in checks.State.ObjectFailureMessages#38684
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ObjectFailureMessages read the shared statuses and failureMsgs maps
without holding c.mu, while the Report* methods write to them under the
lock from concurrent graph-walk goroutines. This can cause panics
("concurrent map read and map write") or incorrect results.
Acquire c.mu for the duration of the read, matching every other public
method on *State (e.g. ObjectCheckStatus). ObjectFailureMessages does not
call back into any *State method, so there is no deadlock risk.
Adds a regression test that fails under `go test -race` without the fix.
Fixes hashicorp#38578
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State.ObjectFailureMessagesreads the sharedstatusesandfailureMsgsmaps without taking
c.mu, but theReport*methods write to those same mapsunder the lock while Terraform Core walks the graph concurrently. That's a data
race — under
-raceit's flagged as one, and in the worst case it surfaces as aconcurrent map read and map writepanic or as wrong/missing failure messages.The fix just holds
c.mufor the duration of the read, the same way every otherreader on
*Statealready does (e.g.ObjectCheckStatus). The method doesn'tcall back into any other
*Statemethod, so there's no risk of deadlocking onthe non-reentrant mutex.
I also added a regression test that runs concurrent writers and readers against a
single
State. It reports a race undergo test -race ./internal/checks/...without the lock and passes with it.
Fixes #38578
Target Release
1.16.x
This has been latent since #31268, so it's also a reasonable backport candidate
if the team wants it in a patch release.
Rollback Plan
Changes to Security Controls
No. This only adds a mutex lock around an existing read — no changes to access
controls, encryption, or logging.
CHANGELOG entry