Protect against deeply nested JSON maps

See gh-31868
This commit is contained in:
Phillip Webb 2022-07-26 15:52:57 +01:00
parent 4132414206
commit da91cde304

View File

@ -42,7 +42,7 @@ public class BasicJsonParser extends AbstractJsonParser {
@Override
public Map<String, Object> parseMap(String json) {
return tryParse(() -> parseMap(json, this::parseMapInternal), Exception.class);
return tryParse(() -> parseMap(json, (jsonToParse) -> parseMapInternal(0, jsonToParse)), Exception.class);
}
@Override
@ -67,7 +67,7 @@ public class BasicJsonParser extends AbstractJsonParser {
return parseListInternal(nesting + 1, json);
}
if (json.startsWith("{")) {
return parseMapInternal(json);
return parseMapInternal(nesting, json);
}
if (json.startsWith("\"")) {
return trimTrailingCharacter(trimLeadingCharacter(json, '"'), '"');
@ -87,7 +87,7 @@ public class BasicJsonParser extends AbstractJsonParser {
return json;
}
private Map<String, Object> parseMapInternal(String json) {
private Map<String, Object> parseMapInternal(int nesting, String json) {
Map<String, Object> map = new LinkedHashMap<>();
json = trimLeadingCharacter(trimTrailingCharacter(json, '}'), '{').trim();
for (String pair : tokenize(json)) {
@ -95,7 +95,7 @@ public class BasicJsonParser extends AbstractJsonParser {
Assert.state(values[0].startsWith("\"") && values[0].endsWith("\""),
"Expecting double-quotes around field names");
String key = trimLeadingCharacter(trimTrailingCharacter(values[0], '"'), '"');
Object value = parseInternal(0, values[1]);
Object value = parseInternal(nesting, values[1]);
map.put(key, value);
}
return map;