Merge pull request #5602 from kolyshkin/1.5-5520

[1.5] libct/specconv: do not pass "defaults" as mount data

libcontainer/specconv/spec_linux.go

@@ -78,7 +78,7 @@ func initMaps() {
 			"async":         {true, unix.MS_SYNCHRONOUS},
 			"atime":         {true, unix.MS_NOATIME},
 			"bind":          {false, unix.MS_BIND},
-			"defaults":      {false, 0},
+			"defaults":      {false, 0}, // no-op, must not be passed as data
 			"dev":           {true, unix.MS_NODEV},
 			"diratime":      {true, unix.MS_NODIRATIME},
 			"dirsync":       {false, unix.MS_DIRSYNC},
@@ -1142,9 +1142,8 @@ func parseMountOptions(options []string) *configs.Mount {
 	initMaps()
 	for _, o := range options {
 		// If the option does not exist in the mountFlags table,
-		// or the flag is not supported on the platform,
 		// then it is a data value for a specific fs type.
-		if f, exists := mountFlags[o]; exists && f.flag != 0 {
+		if f, exists := mountFlags[o]; exists {
 			// FIXME: The *atime flags are special (they are more of an enum
 			// with quite hairy semantics) and thus arguably setting some of
 			// them should clear unrelated flags.

libcontainer/specconv/spec_linux_test.go

@@ -1026,3 +1026,44 @@ func TestCreateNetDevices(t *testing.T) {
 		})
 	}
 }
+
+func TestParseMountOptions(t *testing.T) {
+	tests := []struct {
+		name    string
+		options []string
+		flags   int
+		cleared int
+		data    string
+	}{
+		{
+			name:    "defaults is not data",
+			options: []string{"defaults", "size=1m", "mode=777"},
+			data:    "size=1m,mode=777",
+		},
+		{
+			name:    "unknown options are data",
+			options: []string{"defaults", "notarealoption", "size=1m"},
+			data:    "notarealoption,size=1m",
+		},
+		{
+			name:    "flags are set and cleared",
+			options: []string{"ro", "nodev", "rw"},
+			flags:   unix.MS_NODEV,
+			cleared: unix.MS_RDONLY,
+		},
+	}
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			m := parseMountOptions(tc.options)
+			if m.Flags != tc.flags {
+				t.Errorf("expected flags %#x, got %#x", tc.flags, m.Flags)
+			}
+			if m.ClearedFlags != tc.cleared {
+				t.Errorf("expected cleared flags %#x, got %#x", tc.cleared, m.ClearedFlags)
+			}
+			if m.Data != tc.data {
+				t.Errorf("expected data %q, got %q", tc.data, m.Data)
+			}
+		})
+	}
+}