S3: clone putUserMetadata map to prevent concurrent modification #78
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Changes
When pulling in the latest objstore in a Mimir PR (grafana/mimir#6061) the tests ran into a data race:
Logs
From those logs I determined the race was from concurrent modification to the
putUserMetadata
map stored inBucket
:The map is passed directly into the
PutObjectOptions
from theBucket
struct in s3'sUpload
:The problem fixed in #77 caused the upload to be done by minio's putObjectMultipartStreamNoLength, which surpisingly modifies the map passed in by writing/deleting
"X-Amz-Checksum-Algorithm"
.Verification
Reran the affected test locally with this modification vendored.