What causes "nil arguments" in hyperledger/fabric?

Ensure the submitted Envelope has both Payload and Signature populated before calling ValidateTransaction

nil arguments

Error message

nil arguments

What it means

checkSignatureFromCreator validates that a transaction was signed by its declared creator. It requires the serialized creator identity, the signature, and the signed message bytes to all be non-nil. If any of these three inputs is nil, there is nothing to verify, so the function immediately returns this error without touching MSP or crypto.

Source

Thrown at core/common/validation/msgvalidation.go:31

	"github.com/hyperledger/fabric-lib-go/common/flogging"
	"github.com/hyperledger/fabric-protos-go-apiv2/common"
	pb "github.com/hyperledger/fabric-protos-go-apiv2/peer"
	mspmgmt "github.com/hyperledger/fabric/msp/mgmt"
	"github.com/hyperledger/fabric/protoutil"
	"github.com/pkg/errors"
)

var putilsLogger = flogging.MustGetLogger("protoutils")

// given a creator, a message and a signature,
// this function returns nil if the creator
// is a valid cert and the signature is valid
func checkSignatureFromCreator(creatorBytes, sig, msg []byte, ChannelID string, cryptoProvider bccsp.BCCSP) error {
	putilsLogger.Debugf("begin")

	// check for nil argument
	if creatorBytes == nil || sig == nil || msg == nil {
		return errors.New("nil arguments")
	}

	mspObj := mspmgmt.GetIdentityDeserializer(ChannelID, cryptoProvider)
	if mspObj == nil {
		return errors.Errorf("could not get msp for channel [%s]", ChannelID)
	}

	// get the identity of the creator
	creator, err := mspObj.DeserializeIdentity(creatorBytes)
	if err != nil {
		return errors.WithMessage(err, "MSP error")
	}

	putilsLogger.Debugf("creator is %s", creator.GetIdentifier())

	// ensure that creator is a valid certificate
	err = creator.Validate()
	if err != nil {

View on GitHub (pinned to 2736b63f8f)

Solutions

Ensure the submitted Envelope has both Payload and Signature populated before calling ValidateTransaction
Add a nil check on envelope.Signature / envelope.Payload in the submit path and reject the tx earlier with a clearer client-side message
In tests, pass non-empty byte slices for creatorBytes, sig, and msg, or assert this error is the expected outcome

Example fix

// before
err := validation.ValidateTransaction(&common.Envelope{Payload: payloadBytes}, cryptoProvider)
// after
if env.Signature == nil || env.Payload == nil {
    return errors.New("envelope must contain payload and signature")
}
err := validation.ValidateTransaction(env, cryptoProvider)

Defensive patterns

Strategy: validation

Validate before calling

func validEnvelope(env *common.Envelope) bool {
    return env != nil && env.Payload != nil && env.Signature != nil
}
// call only if validEnvelope(env) before ValidateTransaction

Type guard

func hasSignatureAndPayload(env *common.Envelope) bool {
    return env != nil && len(env.Payload) > 0 && len(env.Signature) > 0
}

Try / catch

err := validation.ValidateTransaction(env, cryptoProvider)
if err != nil && err.Error() == "nil arguments" {
    // reject as MALFORMED_TX: envelope missing payload or signature
}

Prevention

Always sign the payload bytes and attach Signature before validation
Check protobuf optional fields for nil after unmarshalling envelopes
Add early client-side structural validation of Envelope before submit

When it happens

Trigger: Calling checkSignatureFromCreator (directly or via ValidateTransaction) with creatorBytes == nil, sig == nil, or msg == nil — typically when a parsed Envelope has a nil Signature field or a nil Payload, or when a test passes partial byte slices.

Common situations: Hand-constructed envelopes in tests, protobuf unmarshalling that leaves optional fields nil (e.g. Envelope.Signature unset), or upstream code failing to check that payload/signature bytes were present before invoking validation.

Related errors

AI-assisted analysis of hyperledger/fabric@2736b63f8f (2026-09-04). Data as JSON: /api/errors/3d57737a3c2f80ed. Report an issue: GitHub.