Something like this:

From 099131a5010c02a811deb5334709c01ad97ab1b8 Mon Sep 17 00:00:00 2001
From: Colin Walters <walters>
Date: Tue, 8 Dec 2015 11:11:15 -0500
Subject: [PATCH] creds: Use uint32 for loginuid to not overflow 32 bit arches

---
 api/server/credentials_linux.go | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/api/server/credentials_linux.go b/api/server/credentials_linux.go
index 3031911..6879721 100644
--- a/api/server/credentials_linux.go
+++ b/api/server/credentials_linux.go
@@ -72,7 +72,7 @@ func getUcred(fd int) (*syscall.Ucred, error) {
 }
 
 //Gets the client's loginuid
-func getLoginUID(ucred *syscall.Ucred, fd int) (int, error) {
+func getLoginUID(ucred *syscall.Ucred, fd int) (uint32, error) {
 	if _, err := syscall.Getpeername(fd); err != nil {
 		logrus.Errorf("Socket appears to have closed: %v", err)
 		return -1, err
@@ -82,16 +82,16 @@ func getLoginUID(ucred *syscall.Ucred, fd int) (int, error) {
 		logrus.Errorf("Error reading loginuid: %v", err)
 		return -1, err
 	}
-	loginuidInt, err := strconv.Atoi(string(loginuid))
+	loginuidInt, err := strconv.ParseUint(string(loginuid), 10, 32)
 	if err != nil {
-		logrus.Errorf("Failed to convert loginuid to int: %v", err)
+		logrus.Errorf("Failed to convert loginuid to uint32: %v", err)
 	}
-	return loginuidInt, nil
+	return uint32(loginuidInt), nil
 }
 
 //Given a loginUID, retrieves the current username
-func getpwuid(loginUID int) (string, error) {
-	pwd, err := user.LookupId(strconv.Itoa(loginUID))
+func getpwuid(loginUID uint32) (string, error) {
+	pwd, err := user.LookupId(strconv.FormatUint(loginUID, 32))
 	if err != nil {
 		logrus.Errorf("Failed to get pwuid struct: %v", err)
 		return "", err
@@ -255,7 +255,7 @@ func (s *Server) LogAction(w http.ResponseWriter, r *http.Request) error {
 }
 
 //Logs an API event to the audit log
-func logAuditlog(c *container.Container, action string, username string, loginuid int, success bool) {
+func logAuditlog(c *container.Container, action string, username string, loginuid uint32, success bool) {
 	virt := audit.AuditVirtControl
 	vm := "?"
 	vmPid := "?"
-- 
1.8.3.1