Avoid crashing on invalid certain forms of invalid metadata (found in obfuscated assemblies)

ICSharpCode.Decompiler/CSharp/Resolver/CSharpResolver.cs

@@ -1432,6 +1432,10 @@ namespace ICSharpCode.Decompiler.CSharp.Resolver
 				TypeCode code = ReflectionHelper.GetTypeCode(underlyingType);
 				if (code >= TypeCode.Boolean && code <= TypeCode.Decimal && expression.ConstantValue != null)
 				{
+					if (expression.ConstantValue is string)
+					{
+						return new ErrorResolveResult(targetType);
+					}
 					try
 					{
 						return new ConstantResolveResult(targetType, CSharpPrimitiveCast(code, expression.ConstantValue));
@@ -1454,6 +1458,10 @@ namespace ICSharpCode.Decompiler.CSharp.Resolver
 				}
 				else if ((underlyingType.Kind == TypeKind.NInt || underlyingType.Kind == TypeKind.NUInt) && expression.ConstantValue != null)
 				{
+					if (expression.ConstantValue is string)
+					{
+						return new ErrorResolveResult(targetType);
+					}
 					code = (underlyingType.Kind == TypeKind.NInt ? TypeCode.Int32 : TypeCode.UInt32);
 					try
 					{

ICSharpCode.Decompiler/TypeSystem/MetadataModule.cs

@@ -471,7 +471,10 @@ namespace ICSharpCode.Decompiler.TypeSystem
 		IMethod ResolveMethodReference(MemberReferenceHandle memberRefHandle, GenericContext context, IReadOnlyList<IType> methodTypeArguments = null, bool expandVarArgs = true)
 		{
 			var memberRef = metadata.GetMemberReference(memberRefHandle);
-			Debug.Assert(memberRef.GetKind() == MemberReferenceKind.Method);
+			if (memberRef.GetKind() != MemberReferenceKind.Method)
+			{
+				throw new BadImageFormatException($"Member reference must be method, but was: {memberRef.GetKind()}");
+			}
 			MethodSignature<IType> signature;
 			IReadOnlyList<IType> classTypeArguments = null;
 			IMethod method;