NationalSecurityAgency/ghidra · warning · LSHException

Function tag already exists

Error message

Function tag already exists

What it means

Thrown by fdbInstallTag when query.tag_name already exists in info.functionTags. BSim prevents duplicate tag allocation since each tag occupies a fixed bitmask bit; duplicates would be ambiguous.

Source

Thrown at Ghidra/Features/BSim/src/main/java/ghidra/features/bsim/query/client/AbstractSQLFunctionDatabase.java:2232

	public List<String> getFunctionTags() {
		return info.functionTags;
	}

	/**
	 * Entry point for the InstallTagRequest command
	 * @param query the install query to execute
	 * @throws LSHException if the function tag already exists or is not valid
	 * @throws SQLException if there is an error issuing the query
	 */
	private void fdbInstallTag(InstallTagRequest query) throws LSHException, SQLException {
		ResponseInfo response = query.installresponse;
		if (!CategoryRecord.enforceTypeCharacters(query.tag_name)) {
			throw new LSHException("Bad characters in proposed function tag");
		}
		// Check for existing tag
		if (info.functionTags != null) {
			if (info.functionTags.contains(query.tag_name)) {
				throw new LSHException("Function tag already exists");
			}
		}
		if (info.functionTags == null) {
			info.functionTags = new ArrayList<>();
		}
		// There are only 32-bits of space in the function record reserved for storing the presence of tags
		if (info.functionTags.size() >= FunctionTagBSimFilterType.MAX_TAG_COUNT) {
			throw new LSHException(
				"Cannot allocate new function tag: " + query.tag_name + " - Column space is full");
		}
		info.functionTags.add(query.tag_name);
		keyValueTable.writeFunctionTags(info);
		response.info = info;
	}

	/**
	 * Entry point for the InstallMetadataRequest command
	 * @param query the query to execute

View on GitHub (pinned to d5f144c24d)

Solutions

1. Pre-check info.functionTags for the tag name and skip if present.
2. Make tag-installation code idempotent.
3. Fetch current tags via QueryInfo before attempting installation.

Example fix

// before
db.execute(installTagReq); // may already exist
// after
if (info.functionTags == null || !info.functionTags.contains(req.tag_name)) {
    db.execute(installTagReq);
}

List<String> existing = db.getDatabaseInformation().functionTags;
if (existing == null || !existing.contains(req.tag_name)) {
    db.execute(req);
}

catch (LSHException e) { if (e.getMessage().contains("already exists")) { /* benign on re-run */ } else throw e; }

When it happens

Trigger: Issuing an InstallTagRequest for a tag_name already present in the database's loaded functionTags list; re-running tag setup scripts without checking.

Common situations: Re-running initialization scripts; concurrent clients racing to install the same tag; migration/import tooling that doesn't first query existing tags.

Related errors

• Executable category already exists
• No thresholds have been established
• Cannot reset singled executable
• database in use
• Connection with database not established

AI-assisted analysis of NationalSecurityAgency/ghidra@d5f144c24d (2026-08-14). Data as JSON: /api/errors/ce2f574102270035. Report an issue: GitHub.