aws: Fix SIGSEGV when using instance selector

cmd/kops/toolbox_instance-selector.go

@@ -271,9 +271,11 @@ func RunToolboxInstanceSelector(ctx context.Context, f commandutils.Factory, out
 		return fmt.Errorf("error initializing AWS client: %v", err)
 	}
 
-	instanceSelector := selector.Selector{
-		EC2: cloud.EC2(),
+	sess, err := cloud.Session()
+	if err != nil {
+		return err
 	}
+	instanceSelector := selector.New(sess)
 
 	igCount := options.InstanceGroupCount
 	filters := getFilters(commandline, region, zones)

upup/pkg/fi/cloudup/awsup/aws_cloud.go

@@ -124,6 +124,7 @@ const AWSErrCodeInvalidAction = "InvalidAction"
 type AWSCloud interface {
 	fi.Cloud
 	CloudFormation() *cloudformation.CloudFormation
+	Session() (*session.Session, error)
 	EC2() ec2iface.EC2API
 	IAM() iamiface.IAMAPI
 	ELB() elbiface.ELBAPI
@@ -404,6 +405,22 @@ func NewAWSCloud(region string, tags map[string]string) (AWSCloud, error) {
 	return i, nil
 }
 
+func (c *awsCloudImplementation) Session() (*session.Session, error) {
+	config := aws.NewConfig().WithRegion(c.region)
+	config = config.WithCredentialsChainVerboseErrors(true)
+	config = request.WithRetryer(config, newLoggingRetryer(ClientMaxRetries))
+
+	sess, err := session.NewSessionWithOptions(session.Options{
+		Config:            *config,
+		SharedConfigState: session.SharedConfigEnable,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("failed to create session: %w", err)
+	}
+
+	return sess, err
+}
+
 func (c *awsCloudImplementation) addHandlers(regionName string, h *request.Handlers) {
 	delayer := c.getCrossRequestRetryDelay(regionName)
 	if delayer != nil {

upup/pkg/fi/cloudup/awsup/mock_aws_cloud.go

@@ -20,6 +20,7 @@ import (
 	"fmt"
 
 	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/autoscaling/autoscalingiface"
 	"github.com/aws/aws-sdk-go/service/cloudformation"
 	"github.com/aws/aws-sdk-go/service/ec2"
@@ -400,3 +401,7 @@ func (c *MockAWSCloud) DescribeInstanceType(instanceType string) (*ec2.InstanceT
 func (c *MockAWSCloud) AccountInfo() (string, string, error) {
 	return "123456789012", "aws-test", nil
 }
+
+func (c *MockAWSCloud) Session() (*session.Session, error) {
+	return nil, nil
+}