hyperledger/fabric · error

LSCC invocation is attempting to write to namespace %s

Error message

LSCC invocation is attempting to write to namespace %s

What it means

An lscc deploy/upgrade transaction may only write to two namespaces: "lscc" itself and the chaincode being deployed/upgraded. Any other namespace with writes indicates the transaction is trying to smuggle in extra ledger mutations, so it is rejected as a policy violation.

Source

Thrown at core/handlers/validation/builtin/v12/validation_logic.go:626

		}
		// the value must be a ChaincodeData struct
		cdRWSet := &ccprovider.ChaincodeData{}
		err = proto.Unmarshal(lsccrwset.Writes[0].Value, cdRWSet)
		if err != nil {
			return policyErr(fmt.Errorf("unmarshalling of ChaincodeData failed, error %s", err))
		}
		// the chaincode name in the lsccwriteset must match the chaincode name in the deployment spec
		if cdRWSet.Name != cdsArgs.ChaincodeSpec.ChaincodeId.Name {
			return policyErr(fmt.Errorf("expected cc name %s, found %s", cdsArgs.ChaincodeSpec.ChaincodeId.Name, cdRWSet.Name))
		}
		// the chaincode version in the lsccwriteset must match the chaincode version in the deployment spec
		if cdRWSet.Version != cdsArgs.ChaincodeSpec.ChaincodeId.Version {
			return policyErr(fmt.Errorf("expected cc version %s, found %s", cdsArgs.ChaincodeSpec.ChaincodeId.Version, cdRWSet.Version))
		}
		// it must only write to 2 namespaces: LSCC's and the cc that we are deploying/upgrading
		for _, ns := range txRWSet.NsRwSets {
			if ns.NameSpace != "lscc" && ns.NameSpace != cdRWSet.Name && len(ns.KvRwSet.Writes) > 0 {
				return policyErr(fmt.Errorf("LSCC invocation is attempting to write to namespace %s", ns.NameSpace))
			}
		}

		logger.Debugf("Validating %s for cc %s version %s", lsccFunc, cdRWSet.Name, cdRWSet.Version)

		switch lsccFunc {
		case lscc.DEPLOY:

			/******************************************************************/
			/* security check 1 - cc not in the LCCC table of instantiated cc */
			/******************************************************************/
			if ccExistsOnLedger {
				return policyErr(fmt.Errorf("Chaincode %s is already instantiated", cdsArgs.ChaincodeSpec.ChaincodeId.Name))
			}

			/****************************************************************************/
			/* security check 2 - validation of rwset (and of collections if enabled) */
			/****************************************************************************/

View on GitHub (pinned to 2736b63f8f)

Solutions

1. Remove any PutState/DelState calls to other namespaces (e.g. 'lscc', other chaincode ids) from the chaincode's Init/upgrade path.
2. Use proper cross-chaincode invocation (InvokeChaincode) instead of direct namespace writes.
3. Ensure the rwset is generated from a single simulated transaction, not merged.
4. Audit the chaincode's init code with peer's rwset inspection before instantiating.

Example fix

// before
stub.PutState("othercc", key, value) // foreign namespace write
// after
stub.InvokeChaincode("othercc", args, channel) // proper cross-cc call

for _, ns := range txRWSet.NsRwSets {
    if ns.NameSpace != "lscc" && ns.NameSpace != cd.Name && len(ns.KvRwSet.Writes) > 0 {
        return fmt.Errorf("chaincode writes to forbidden namespace %q during lscc deploy", ns.NameSpace)
    }
}

func onlyAllowedNamespaces(txRWSet *rwset.TxRwSet, ccName string) bool {
    for _, ns := range txRWSet.NsRwSets {
        if ns.NameSpace != "lscc" && ns.NameSpace != ccName && len(ns.KvRwSet.Writes) > 0 {
            return false
        }
    }
    return true
}

if err := submitTx(envelope); err != nil {
    if strings.Contains(err.Error(), "attempting to write to namespace") {
        // remove foreign PutState calls from the chaincode Init/upgrade path and redeploy
    }
}

When it happens

Trigger: txRWSet contains an NsRwSet for a namespace other than lscc or cdRWSet.Name with len(KvRwSet.Writes) > 0 — e.g. the invoking chaincode wrote to another chaincode's keys during the same transaction, or the rwset was merged from multiple transactions.

Common situations: Chaincode implementations that call PutState into foreign namespaces during init; cross-chaincode write attempts without proper cross-chaincode calls; rwset aggregation bugs or malicious transaction crafting.

Related errors

• No read write set for lscc was found
• LSCC must issue at least one single putState upon deploy/upg
• no instantiation policy was specified
• LSCC can only issue a single putState upon upgrade
• LSCC can only issue one or two putState upon deploy

AI-assisted analysis of hyperledger/fabric@2736b63f8f (2026-09-04). Data as JSON: /api/errors/6b83463aab9509bc. Report an issue: GitHub.