{"record":{"id":"528bd63699e5ca92","repo":"hyperledger/fabric","slug":"failed-to-unmarshal-deployment-spec-from-bytes","errorCode":null,"errorMessage":"failed to unmarshal deployment spec from bytes","messagePattern":"failed to unmarshal deployment spec from bytes","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"core/common/ccprovider/cdspackage.go","lineNumber":184,"sourceCode":"\totherdata := &CDSData{}\n\terr := proto.Unmarshal(ccdata.Data, otherdata)\n\tif err != nil {\n\t\treturn err\n\t}\n\n\tif !proto.Equal(ccpack.data, otherdata) {\n\t\treturn errors.New(\"data mismatch\")\n\t}\n\n\treturn nil\n}\n\n// InitFromBuffer sets the buffer if valid and returns ChaincodeData\nfunc (ccpack *CDSPackage) InitFromBuffer(buf []byte) (*ChaincodeData, error) {\n\tdepSpec := &pb.ChaincodeDeploymentSpec{}\n\terr := proto.Unmarshal(buf, depSpec)\n\tif err != nil {\n\t\treturn nil, errors.New(\"failed to unmarshal deployment spec from bytes\")\n\t}\n\n\tdatabytes, id, data, err := ccpack.getCDSData(depSpec)\n\tif err != nil {\n\t\treturn nil, err\n\t}\n\n\tccpack.buf = buf\n\tccpack.depSpec = depSpec\n\tccpack.data = data\n\tccpack.datab = databytes\n\tccpack.id = id\n\n\treturn ccpack.GetChaincodeData(), nil\n}\n\n// InitFromPath returns the chaincode and its package from the file system\nfunc (ccpack *CDSPackage) InitFromPath(ccNameVersion string, path string) ([]byte, *pb.ChaincodeDeploymentSpec, error) {","sourceCodeStart":166,"sourceCodeEnd":202,"githubUrl":"https://github.com/hyperledger/fabric/blob/2736b63f8fd5932511d56fe68b7039d15977f7f6/core/common/ccprovider/cdspackage.go#L166-L202","documentation":"CDSPackage.InitFromBuffer unmarshals the given buffer as a ChaincodeDeploymentSpec protobuf. If proto.Unmarshal fails, the buffer is not a valid CDS, so it returns this fixed error instead of exposing the protobuf internals. The package is intentionally left uninitialized.","triggerScenarios":"Calling InitFromBuffer with bytes that are not a serialized ChaincodeDeploymentSpec — empty input, garbage bytes, a SignedCDS where a plain CDS is required, or a package serialized by an incompatible protobuf schema.","commonSituations":"Reading a truncated/corrupt package file from disk; passing wrong buffer from an upstream caller like buildPackage or PutChaincode; schema drift between Fabric versions.","solutions":["Verify the buffer is a complete, uncorrupted CDS protobuf before calling InitFromBuffer","Regenerate the package (peer chaincode package/install) with a matching Fabric version","Confirm you are not passing a SignedCDS buffer to CDSPackage.InitFromBuffer","Check file integrity (size, checksum) at the source of the bytes"],"exampleFix":"// before\nbuf, _ := ioutil.ReadFile(pkgPath) // truncated file ignored\nccpack.InitFromBuffer(buf)\n// after\nbuf, err := ioutil.ReadFile(pkgPath)\nif err != nil { return err }\nif len(buf) == 0 { return errors.New(\"empty package buffer\") }\nccpack.InitFromBuffer(buf)","handlingStrategy":"try-catch","validationCode":"func validCDSBuffer(buf []byte) bool {\n    if len(buf) == 0 { return false }\n    spec := &pb.ChaincodeDeploymentSpec{}\n    if err := proto.Unmarshal(buf, spec); err != nil { return false }\n    return spec.ChaincodeSpec != nil && spec.ChaincodeSpec.ChaincodeId != nil && spec.ChaincodeSpec.ChaincodeId.Name != \"\"\n}","typeGuard":"func isInitBufferSafe(buf []byte) bool {\n    spec := &pb.ChaincodeDeploymentSpec{}\n    return len(buf) > 0 && proto.Unmarshal(buf, spec) == nil && spec.ChaincodeSpec != nil\n}","tryCatchPattern":"ccpack := &ccprovider.CDSPackage{}\nif _, err := ccpack.InitFromBuffer(buf); err != nil {\n    if err.Error() == \"failed to unmarshal deployment spec from bytes\" {\n        return fmt.Errorf(\"buffer (%d bytes) is not a ChaincodeDeploymentSpec: %w\", len(buf), err)\n    }\n    return err\n}","preventionTips":["Pre-validate the buffer parses as CDS with proto.Unmarshal before InitFromBuffer","Check file size/checksum after reading package files to catch truncation","Use SignedCDS APIs for signed packages, plain CDS APIs otherwise","Match protobuf schema versions between producer and consumer of the buffer"],"tags":["hyperledger-fabric","protobuf","unmarshal","chaincode"],"backgroundTag":"protobuf-unmarshal-failed","analyzedSha":"2736b63f8fd5932511d56fe68b7039d15977f7f6","analyzedAt":"2026-09-04T08:52:36.465Z","contentChangedAt":"2026-09-04T08:52:36.465Z","schemaVersion":2},"datasetVersion":"2026-09-08T10:18:20.063Z"}