diff --git a/libcontainer/system/linux.go b/libcontainer/system/linux.go
index f7260256047..eb301073cde 100644
--- a/libcontainer/system/linux.go
+++ b/libcontainer/system/linux.go
@@ -100,12 +100,12 @@ func RunningInUserNS() bool {
 			// This kernel-provided file only exists if user namespaces are supported
 			return
 		}
-		inUserNS = UIDMapInUserNS(uidmap)
+		inUserNS = uidMapInUserNS(uidmap)
 	})
 	return inUserNS
 }
 
-func UIDMapInUserNS(uidmap []user.IDMap) bool {
+func uidMapInUserNS(uidmap []user.IDMap) bool {
 	/*
 	 * We assume we are in the initial user namespace if we have a full
 	 * range - 4294967295 uids starting at uid 0.
diff --git a/libcontainer/system/linux_test.go b/libcontainer/system/linux_test.go
index 4d613d8473d..08e2d6c3b92 100644
--- a/libcontainer/system/linux_test.go
+++ b/libcontainer/system/linux_test.go
@@ -37,7 +37,7 @@ func TestUIDMapInUserNS(t *testing.T) {
 		if err != nil {
 			t.Fatal(err)
 		}
-		actual := UIDMapInUserNS(uidmap)
+		actual := uidMapInUserNS(uidmap)
 		if c.expected != actual {
 			t.Fatalf("expected %v, got %v for %q", c.expected, actual, c.s)
 		}
diff --git a/libcontainer/system/system_fuzzer.go b/libcontainer/system/system_fuzzer.go
index c1d7630fefa..2354247ebef 100644
--- a/libcontainer/system/system_fuzzer.go
+++ b/libcontainer/system/system_fuzzer.go
@@ -10,6 +10,6 @@ import (
 
 func FuzzUIDMap(data []byte) int {
 	uidmap, _ := user.ParseIDMap(strings.NewReader(string(data)))
-	_ = UIDMapInUserNS(uidmap)
+	_ = uidMapInUserNS(uidmap)
 	return 1
 }
diff --git a/libcontainer/system/unsupported.go b/libcontainer/system/unsupported.go
index 0adf94012b3..829d9dac00e 100644
--- a/libcontainer/system/unsupported.go
+++ b/libcontainer/system/unsupported.go
@@ -12,8 +12,8 @@ func RunningInUserNS() bool {
 	return false
 }
 
-// UIDMapInUserNS is a stub for non-Linux systems
+// uidMapInUserNS is a stub for non-Linux systems
 // Always returns false
-func UIDMapInUserNS(uidmap []user.IDMap) bool {
+func uidMapInUserNS(uidmap []user.IDMap) bool {
 	return false
 }