Merge "Sandbox environment variables" into main

android/rule_builder.go

@@ -463,6 +463,8 @@ func (r *RuleBuilder) Build(name string, desc string) {
 	r.build(name, desc, true)
 }
 
+var sandboxEnvOnceKey = NewOnceKey("sandbox_environment_variables")
+
 func (r *RuleBuilder) build(name string, desc string, ninjaEscapeCommandString bool) {
 	name = ninjaNameEscape(name)
 
@@ -580,16 +582,44 @@ func (r *RuleBuilder) build(name string, desc string, ninjaEscapeCommandString b
 				})
 			}
 
+			// Only allow the build to access certain environment variables
+			command.DontInheritEnv = proto.Bool(true)
+			command.Env = r.ctx.Config().Once(sandboxEnvOnceKey, func() interface{} {
+				// The list of allowed variables was found by running builds of all
+				// genrules and seeing what failed
+				var result []*sbox_proto.EnvironmentVariable
+				inheritedVars := []string{
+					"PATH",
+					"JAVA_HOME",
+					"TMPDIR",
+					// Allow RBE variables because the art tests invoke RBE manually
+					"RBE_log_dir",
+					"RBE_platform",
+					"RBE_server_address",
+					// TODO: RBE_exec_root is set to the absolute path to the root of the source
+					// tree, which we don't want sandboxed actions to find. Remap it to ".".
+					"RBE_exec_root",
+				}
+				for _, v := range inheritedVars {
+					result = append(result, &sbox_proto.EnvironmentVariable{
+						Name: proto.String(v),
+						State: &sbox_proto.EnvironmentVariable_Inherit{
+							Inherit: true,
+						},
+					})
+				}
 				// Set OUT_DIR to the relative path of the sandboxed out directory.
 				// Otherwise, OUT_DIR will be inherited from the rest of the build,
 				// which will allow scripts to escape the sandbox if OUT_DIR is an
 				// absolute path.
-			command.Env = append(command.Env, &sbox_proto.EnvironmentVariable{
+				result = append(result, &sbox_proto.EnvironmentVariable{
 					Name: proto.String("OUT_DIR"),
 					State: &sbox_proto.EnvironmentVariable_Value{
 						Value: sboxOutSubDir,
 					},
 				})
+				return result
+			}).([]*sbox_proto.EnvironmentVariable)
 			command.Chdir = proto.Bool(true)
 		}
 

cmd/sbox/sbox.go

@@ -275,7 +275,10 @@ func createEnv(command *sbox_proto.Command) ([]string, error) {
 			if !state.Inherit {
 				return nil, fmt.Errorf("Can't have inherit set to false")
 			}
-			env = append(env, *envVar.Name+"="+os.Getenv(*envVar.Name))
+			val, ok := os.LookupEnv(*envVar.Name)
+			if ok {
+				env = append(env, *envVar.Name+"="+val)
+			}
 		default:
 			return nil, fmt.Errorf("Unhandled state type")
 		}