Virtualbox executor panics when trying to upload artifacts

I have the gitlab-runner set up with the virtualbox executor and it successfully clones the host vm, starts it and runs the pipeline, the exector a VM is getting this error

Uploading artifacts...
panic: reflect: call of reflect.Value.Type on zero Value [recovered]
	panic: reflect: call of reflect.Value.Type on zero Value

goroutine 1 [running]:
main.main.func1()
	/go/src/gitlab.com/gitlab-org/gitlab-ci-multi-runner/main.go:32 +0x7f
panic(0x14fcc60, 0xc4204aa200)
	/usr/local/go/src/runtime/panic.go:489 +0x2cf
reflect.Value.Type(0x0, 0x0, 0x0, 0x410a9f, 0xc42016d250)
	/usr/local/go/src/reflect/value.go:1688 +0x21f
gitlab.com/gitlab-org/gitlab-ci-multi-runner/vendor/gitlab.com/ayufan/golang-cli-helpers.convertMarshal(0x0, 0x0, 0x0, 0xc42016d2b0, 0x4d5dc1, 0xc420091540, 0xc42016d2c0, 0x41db87)
	/go/src/gitlab.com/gitlab-org/gitlab-ci-multi-runner/vendor/gitlab.com/ayufan/golang-cli-helpers/convert.go:47 +0x43
gitlab.com/gitlab-org/gitlab-ci-multi-runner/vendor/gitlab.com/ayufan/golang-cli-helpers.convertToString(0x0, 0x0, 0x0, 0x0, 0x0, 0xc42037af80, 0x444fb8, 0x2a, 0x2dc62e6d1d9)
	/go/src/gitlab.com/gitlab-org/gitlab-ci-multi-runner/vendor/gitlab.com/ayufan/golang-cli-helpers/convert.go:58 +0x5a
gitlab.com/gitlab-org/gitlab-ci-multi-runner/vendor/gitlab.com/ayufan/golang-cli-helpers.StructFieldValue.String(0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...)
	/go/src/gitlab.com/gitlab-org/gitlab-ci-multi-runner/vendor/gitlab.com/ayufan/golang-cli-helpers/struct_field.go:32 +0x7b
gitlab.com/gitlab-org/gitlab-ci-multi-runner/vendor/gitlab.com/ayufan/golang-cli-helpers.(*StructFieldValue).String(0xc42037af80, 0x15f73a0, 0xc42037af80)
	<autogenerated>:5 +0x70
flag.isZeroValue(0xc4203a33c0, 0x0, 0x0, 0x14922e7)
	/usr/local/go/src/flag/flag.go:395 +0x102
flag.(*FlagSet).PrintDefaults.func1(0xc4203a33c0)
	/usr/local/go/src/flag/flag.go:469 +0x1b9
flag.(*FlagSet).VisitAll(0xc4204a8060, 0xc42016d610)
	/usr/local/go/src/flag/flag.go:325 +0x67
flag.(*FlagSet).PrintDefaults(0xc4204a8060)
	/usr/local/go/src/flag/flag.go:478 +0x4f
flag.(*FlagSet).defaultUsage(0xc4204a8060)
	/usr/local/go/src/flag/flag.go:511 +0x8e
flag.(*FlagSet).(flag.defaultUsage)-fm()
	/usr/local/go/src/flag/flag.go:973 +0x2a
flag.(*FlagSet).usage(0xc4204a8060)
	/usr/local/go/src/flag/flag.go:826 +0x2f
flag.(*FlagSet).failf(0xc4204a8060, 0x1719425, 0x22, 0xc42016d898, 0x1, 0x1, 0x0, 0x16f8e6d)
	/usr/local/go/src/flag/flag.go:816 +0xea
flag.(*FlagSet).parseOne(0xc4204a8060, 0xc42000e101, 0x0, 0x0)
	/usr/local/go/src/flag/flag.go:871 +0x2ee
flag.(*FlagSet).Parse(0xc4204a8060, 0xc42000e120, 0xe, 0xe, 0x31de860, 0x0)
	/usr/local/go/src/flag/flag.go:913 +0x60
gitlab.com/gitlab-org/gitlab-ci-multi-runner/vendor/github.com/codegangsta/cli.Command.Run(0x17057a4, 0x12, 0x0, 0x0, 0x0, 0x0, 0x0, 0x1724306, 0x2c, 0x0, ...)
	/go/src/gitlab.com/gitlab-org/gitlab-ci-multi-runner/vendor/github.com/codegangsta/cli/command.go:98 +0xb59
gitlab.com/gitlab-org/gitlab-ci-multi-runner/vendor/github.com/codegangsta/cli.(*App).Run(0xc420363b00, 0xc42000e100, 0x10, 0x10, 0x0, 0x0)
	/go/src/gitlab.com/gitlab-org/gitlab-ci-multi-runner/vendor/github.com/codegangsta/cli/app.go:159 +0x56f
main.main()
	/go/src/gitlab.com/gitlab-org/gitlab-ci-multi-runner/main.go:58 +0x2af

it also outputs this on debug:

no referees configured                              context=referee job=267 project=1 runner=igjLjEGk
WARNING: Job failed: Process exited with status 1   duration=28.2960988s job=267 project=1 runner=igjLjEGk
WARNING: Failed to process runner                   builds=0 error=Process exited with status 1 executor=virtualbox runner=igjLjEGk