fix(subagents) share execpolicy by default (#13702)

## Summary
If a subagent requests approval, and the user persists that approval to
the execpolicy, it should (by default) propagate. We'll need to rethink
this a bit in light of coming Permissions changes, though I think this
is closer to the end state that we'd want, which is that execpolicy
changes to one permissions profile should be synced across threads.

## Testing
- [x] Added integration test

---------

Co-authored-by: Codex <noreply@openai.com>

codex-rs/core/src/agent/control.rs

@@ -107,6 +107,9 @@ impl AgentControl {
         let inherited_shell_snapshot = self
             .inherited_shell_snapshot_for_source(&state, session_source.as_ref())
             .await;
+        let inherited_exec_policy = self
+            .inherited_exec_policy_for_source(&state, session_source.as_ref(), &config)
+            .await;
         let session_source = match session_source {
             Some(SessionSource::SubAgent(SubAgentSource::ThreadSpawn {
                 parent_thread_id,
@@ -189,6 +192,7 @@ impl AgentControl {
                             session_source,
                             /*persist_extended_history*/ false,
                             inherited_shell_snapshot,
+                            inherited_exec_policy,
                         )
                         .await?
                 } else {
@@ -200,6 +204,7 @@ impl AgentControl {
                             /*persist_extended_history*/ false,
                             /*metrics_service_name*/ None,
                             inherited_shell_snapshot,
+                            inherited_exec_policy,
                         )
                         .await?
                 }
@@ -271,6 +276,9 @@ impl AgentControl {
         let inherited_shell_snapshot = self
             .inherited_shell_snapshot_for_source(&state, Some(&session_source))
             .await;
+        let inherited_exec_policy = self
+            .inherited_exec_policy_for_source(&state, Some(&session_source), &config)
+            .await;
         let rollout_path =
             find_thread_path_by_id_str(config.codex_home.as_path(), &thread_id.to_string())
                 .await?
@@ -283,6 +291,7 @@ impl AgentControl {
                 self.clone(),
                 session_source,
                 inherited_shell_snapshot,
+                inherited_exec_policy,
             )
             .await?;
         reservation.commit(resumed_thread.thread_id);
@@ -499,6 +508,30 @@ impl AgentControl {
         let parent_thread = state.get_thread(*parent_thread_id).await.ok()?;
         parent_thread.codex.session.user_shell().shell_snapshot()
     }
+
+    async fn inherited_exec_policy_for_source(
+        &self,
+        state: &Arc<ThreadManagerState>,
+        session_source: Option<&SessionSource>,
+        child_config: &crate::config::Config,
+    ) -> Option<Arc<crate::exec_policy::ExecPolicyManager>> {
+        let Some(SessionSource::SubAgent(SubAgentSource::ThreadSpawn {
+            parent_thread_id, ..
+        })) = session_source
+        else {
+            return None;
+        };
+
+        let parent_thread = state.get_thread(*parent_thread_id).await.ok()?;
+        let parent_config = parent_thread.codex.session.get_config().await;
+        if !crate::exec_policy::child_uses_parent_exec_policy(&parent_config, child_config) {
+            return None;
+        }
+
+        Some(Arc::clone(
+            &parent_thread.codex.session.services.exec_policy,
+        ))
+    }
 }
 #[cfg(test)]
 #[path = "control_tests.rs"]

codex-rs/core/src/codex.rs

@@ -376,6 +376,7 @@ pub(crate) struct CodexSpawnArgs {
     pub(crate) persist_extended_history: bool,
     pub(crate) metrics_service_name: Option<String>,
     pub(crate) inherited_shell_snapshot: Option<Arc<ShellSnapshot>>,
+    pub(crate) inherited_exec_policy: Option<Arc<ExecPolicyManager>>,
     pub(crate) user_shell_override: Option<shell::Shell>,
     pub(crate) parent_trace: Option<W3cTraceContext>,
 }
@@ -429,6 +430,7 @@ impl Codex {
             metrics_service_name,
             inherited_shell_snapshot,
             user_shell_override,
+            inherited_exec_policy,
             parent_trace: _,
         } = args;
         let (tx_sub, rx_sub) = async_channel::bounded(SUBMISSION_CHANNEL_CAPACITY);
@@ -485,11 +487,15 @@ impl Codex {
             // Guardian review should rely on the built-in shell safety checks,
             // not on caller-provided exec-policy rules that could shape the
             // reviewer or silently auto-approve commands.
-            ExecPolicyManager::default()
+            Arc::new(ExecPolicyManager::default())
+        } else if let Some(exec_policy) = &inherited_exec_policy {
+            Arc::clone(exec_policy)
         } else {
-            ExecPolicyManager::load(&config.config_layer_stack)
-                .await
-                .map_err(|err| CodexErr::Fatal(format!("failed to load rules: {err}")))?
+            Arc::new(
+                ExecPolicyManager::load(&config.config_layer_stack)
+                    .await
+                    .map_err(|err| CodexErr::Fatal(format!("failed to load rules: {err}")))?,
+            )
         };
 
         let config = Arc::new(config);
@@ -1386,7 +1392,7 @@ impl Session {
         config: Arc<Config>,
         auth_manager: Arc<AuthManager>,
         models_manager: Arc<ModelsManager>,
-        exec_policy: ExecPolicyManager,
+        exec_policy: Arc<ExecPolicyManager>,
         tx_event: Sender<Event>,
         agent_status: watch::Sender<AgentStatus>,
         initial_history: InitialHistory,

codex-rs/core/src/codex_delegate.rs

@@ -89,6 +89,7 @@ pub(crate) async fn run_codex_thread_interactive(
         metrics_service_name: None,
         inherited_shell_snapshot: None,
         user_shell_override: None,
+        inherited_exec_policy: Some(Arc::clone(&parent_session.services.exec_policy)),
         parent_trace: None,
     })
     .await?;

codex-rs/core/src/codex_tests.rs

@@ -2364,7 +2364,7 @@ async fn session_new_fails_when_zsh_fork_enabled_without_zsh_path() {
         Arc::clone(&config),
         auth_manager,
         models_manager,
-        ExecPolicyManager::default(),
+        Arc::new(ExecPolicyManager::default()),
         tx_event,
         agent_status_tx,
         InitialHistory::New,
@@ -2400,7 +2400,7 @@ pub(crate) async fn make_session_and_context() -> (Session, TurnContext) {
         CollaborationModesConfig::default(),
     ));
     let agent_control = AgentControl::default();
-    let exec_policy = ExecPolicyManager::default();
+    let exec_policy = Arc::new(ExecPolicyManager::default());
     let (agent_status_tx, _agent_status_rx) = watch::channel(AgentStatus::PendingInit);
     let model = ModelsManager::get_model_offline_for_tests(config.model.as_deref());
     let model_info = ModelsManager::construct_model_info_offline_for_tests(model.as_str(), &config);
@@ -3194,7 +3194,7 @@ pub(crate) async fn make_session_and_context_with_dynamic_tools_and_rx(
         CollaborationModesConfig::default(),
     ));
     let agent_control = AgentControl::default();
-    let exec_policy = ExecPolicyManager::default();
+    let exec_policy = Arc::new(ExecPolicyManager::default());
     let (agent_status_tx, _agent_status_rx) = watch::channel(AgentStatus::PendingInit);
     let model = ModelsManager::get_model_offline_for_tests(config.model.as_deref());
     let model_info = ModelsManager::construct_model_info_offline_for_tests(model.as_str(), &config);

codex-rs/core/src/codex_tests_guardian.rs

@@ -452,6 +452,7 @@ async fn guardian_subagent_does_not_inherit_parent_exec_policy_rules() {
         persist_extended_history: false,
         metrics_service_name: None,
         inherited_shell_snapshot: None,
+        inherited_exec_policy: Some(Arc::new(parent_exec_policy)),
         user_shell_override: None,
         parent_trace: None,
     })

codex-rs/core/src/exec_policy.rs

@@ -32,8 +32,10 @@ use tracing::instrument;
 
 use crate::bash::parse_shell_lc_plain_commands;
 use crate::bash::parse_shell_lc_single_command_prefix;
+use crate::config::Config;
 use crate::sandboxing::SandboxPermissions;
 use crate::tools::sandboxing::ExecApprovalRequirement;
+use codex_utils_absolute_path::AbsolutePathBuf;
 use shlex::try_join as shlex_try_join;
 
 const PROMPT_CONFLICT_REASON: &str =
@@ -94,6 +96,24 @@ static BANNED_PREFIX_SUGGESTIONS: &[&[&str]] = &[
     &["osascript"],
 ];
 
+pub(crate) fn child_uses_parent_exec_policy(parent_config: &Config, child_config: &Config) -> bool {
+    fn exec_policy_config_folders(config: &Config) -> Vec<AbsolutePathBuf> {
+        config
+            .config_layer_stack
+            .get_layers(
+                ConfigLayerStackOrdering::LowestPrecedenceFirst,
+                /*include_disabled*/ false,
+            )
+            .into_iter()
+            .filter_map(codex_config::ConfigLayerEntry::config_folder)
+            .collect()
+    }
+
+    exec_policy_config_folders(parent_config) == exec_policy_config_folders(child_config)
+        && parent_config.config_layer_stack.requirements().exec_policy
+            == child_config.config_layer_stack.requirements().exec_policy
+}
+
 fn is_policy_match(rule_match: &RuleMatch) -> bool {
     match rule_match {
         RuleMatch::PrefixRuleMatch { .. } => true,
@@ -170,6 +190,7 @@ pub enum ExecPolicyUpdateError {
 
 pub(crate) struct ExecPolicyManager {
     policy: ArcSwap<Policy>,
+    update_lock: tokio::sync::Mutex<()>,
 }
 
 pub(crate) struct ExecApprovalRequest<'a> {
@@ -185,6 +206,7 @@ impl ExecPolicyManager {
     pub(crate) fn new(policy: Arc<Policy>) -> Self {
         Self {
             policy: ArcSwap::from(policy),
+            update_lock: tokio::sync::Mutex::new(()),
         }
     }
 
@@ -292,11 +314,11 @@ impl ExecPolicyManager {
         codex_home: &Path,
         amendment: &ExecPolicyAmendment,
     ) -> Result<(), ExecPolicyUpdateError> {
+        let _update_guard = self.update_lock.lock().await;
         let policy_path = default_policy_path(codex_home);
-        let prefix = amendment.command.clone();
         spawn_blocking({
             let policy_path = policy_path.clone();
-            let prefix = prefix.clone();
+            let prefix = amendment.command.clone();
             move || blocking_append_allow_prefix_rule(&policy_path, &prefix)
         })
         .await
@@ -306,8 +328,25 @@ impl ExecPolicyManager {
             source,
         })?;
 
-        let mut updated_policy = self.current().as_ref().clone();
-        updated_policy.add_prefix_rule(&prefix, Decision::Allow)?;
+        let current_policy = self.current();
+        let match_options = MatchOptions {
+            resolve_host_executables: true,
+        };
+        let existing_evaluation = current_policy.check_multiple_with_options(
+            [&amendment.command],
+            &|_| Decision::Forbidden,
+            &match_options,
+        );
+        let already_allowed = existing_evaluation.decision == Decision::Allow
+            && existing_evaluation.matched_rules.iter().any(|rule_match| {
+                is_policy_match(rule_match) && rule_match.decision() == Decision::Allow
+            });
+        if already_allowed {
+            return Ok(());
+        }
+
+        let mut updated_policy = current_policy.as_ref().clone();
+        updated_policy.add_prefix_rule(&amendment.command, Decision::Allow)?;
         self.policy.store(Arc::new(updated_policy));
         Ok(())
     }
@@ -320,6 +359,7 @@ impl ExecPolicyManager {
         decision: Decision,
         justification: Option<String>,
     ) -> Result<(), ExecPolicyUpdateError> {
+        let _update_guard = self.update_lock.lock().await;
         let policy_path = default_policy_path(codex_home);
         let host = host.to_string();
         spawn_blocking({

codex-rs/core/src/exec_policy_tests.rs

@@ -1,9 +1,16 @@
 use super::*;
+use crate::config::Config;
+use crate::config::ConfigBuilder;
 use crate::config_loader::ConfigLayerEntry;
 use crate::config_loader::ConfigLayerStack;
+use crate::config_loader::ConfigLayerStackOrdering;
 use crate::config_loader::ConfigRequirements;
 use crate::config_loader::ConfigRequirementsToml;
+use crate::config_loader::LoaderOverrides;
+use crate::config_loader::RequirementSource;
+use crate::config_loader::Sourced;
 use codex_app_server_protocol::ConfigLayerSource;
+use codex_config::RequirementsExecPolicy;
 use codex_protocol::permissions::FileSystemAccessMode;
 use codex_protocol::permissions::FileSystemPath;
 use codex_protocol::permissions::FileSystemSandboxEntry;
@@ -17,6 +24,7 @@ use std::fs;
 use std::path::Path;
 use std::path::PathBuf;
 use std::sync::Arc;
+use tempfile::TempDir;
 use tempfile::tempdir;
 use toml::Value as TomlValue;
 
@@ -73,6 +81,92 @@ fn unrestricted_file_system_sandbox_policy() -> FileSystemSandboxPolicy {
     FileSystemSandboxPolicy::unrestricted()
 }
 
+async fn test_config() -> (TempDir, Config) {
+    let home = TempDir::new().expect("create temp dir");
+    let config = ConfigBuilder::default()
+        .codex_home(home.path().to_path_buf())
+        .loader_overrides(LoaderOverrides {
+            #[cfg(target_os = "macos")]
+            managed_preferences_base64: Some(String::new()),
+            macos_managed_config_requirements_base64: Some(String::new()),
+            ..LoaderOverrides::default()
+        })
+        .build()
+        .await
+        .expect("load default test config");
+    (home, config)
+}
+
+#[tokio::test]
+async fn child_uses_parent_exec_policy_when_layer_stack_matches() {
+    let (_home, parent_config) = test_config().await;
+    let child_config = parent_config.clone();
+
+    assert!(child_uses_parent_exec_policy(&parent_config, &child_config));
+}
+
+#[tokio::test]
+async fn child_uses_parent_exec_policy_when_non_exec_policy_layers_differ() {
+    let (_home, parent_config) = test_config().await;
+    let mut child_config = parent_config.clone();
+    let mut layers: Vec<_> = child_config
+        .config_layer_stack
+        .get_layers(ConfigLayerStackOrdering::LowestPrecedenceFirst, true)
+        .into_iter()
+        .cloned()
+        .collect();
+    layers.push(ConfigLayerEntry::new(
+        ConfigLayerSource::SessionFlags,
+        TomlValue::Table(Default::default()),
+    ));
+    child_config.config_layer_stack = ConfigLayerStack::new(
+        layers,
+        child_config.config_layer_stack.requirements().clone(),
+        child_config.config_layer_stack.requirements_toml().clone(),
+    )
+    .expect("config layer stack");
+
+    assert!(child_uses_parent_exec_policy(&parent_config, &child_config));
+}
+
+#[tokio::test]
+async fn child_does_not_use_parent_exec_policy_when_requirements_exec_policy_differs() {
+    let (_home, parent_config) = test_config().await;
+    let mut child_config = parent_config.clone();
+    let mut requirements = ConfigRequirements {
+        exec_policy: child_config
+            .config_layer_stack
+            .requirements()
+            .exec_policy
+            .clone(),
+        ..ConfigRequirements::default()
+    };
+    let mut policy = Policy::empty();
+    policy
+        .add_prefix_rule(&["rm".to_string()], Decision::Forbidden)
+        .expect("add prefix rule");
+    requirements.exec_policy = Some(Sourced::new(
+        RequirementsExecPolicy::new(policy),
+        RequirementSource::Unknown,
+    ));
+    child_config.config_layer_stack = ConfigLayerStack::new(
+        child_config
+            .config_layer_stack
+            .get_layers(ConfigLayerStackOrdering::LowestPrecedenceFirst, true)
+            .into_iter()
+            .cloned()
+            .collect(),
+        requirements,
+        child_config.config_layer_stack.requirements_toml().clone(),
+    )
+    .expect("config layer stack");
+
+    assert!(!child_uses_parent_exec_policy(
+        &parent_config,
+        &child_config
+    ));
+}
+
 #[tokio::test]
 async fn returns_empty_policy_when_no_policy_files_exist() {
     let temp_dir = tempdir().expect("create temp dir");

codex-rs/core/src/state/service.rs

@@ -44,7 +44,7 @@ pub(crate) struct SessionServices {
     pub(crate) user_shell: Arc<crate::shell::Shell>,
     pub(crate) shell_snapshot_tx: watch::Sender<Option<Arc<crate::shell_snapshot::ShellSnapshot>>>,
     pub(crate) show_raw_agent_reasoning: bool,
-    pub(crate) exec_policy: ExecPolicyManager,
+    pub(crate) exec_policy: Arc<ExecPolicyManager>,
     pub(crate) auth_manager: Arc<AuthManager>,
     pub(crate) models_manager: Arc<ModelsManager>,
     pub(crate) session_telemetry: SessionTelemetry,

codex-rs/core/src/thread_manager.rs

@@ -610,10 +610,12 @@ impl ThreadManagerState {
             /*persist_extended_history*/ false,
             /*metrics_service_name*/ None,
             /*inherited_shell_snapshot*/ None,
+            /*inherited_exec_policy*/ None,
         ))
         .await
     }
 
+    #[allow(clippy::too_many_arguments)]
     pub(crate) async fn spawn_new_thread_with_source(
         &self,
         config: Config,
@@ -622,6 +624,7 @@ impl ThreadManagerState {
         persist_extended_history: bool,
         metrics_service_name: Option<String>,
         inherited_shell_snapshot: Option<Arc<ShellSnapshot>>,
+        inherited_exec_policy: Option<Arc<crate::exec_policy::ExecPolicyManager>>,
     ) -> CodexResult<NewThread> {
         Box::pin(self.spawn_thread_with_source(
             config,
@@ -633,6 +636,7 @@ impl ThreadManagerState {
             persist_extended_history,
             metrics_service_name,
             inherited_shell_snapshot,
+            inherited_exec_policy,
             /*parent_trace*/ None,
             /*user_shell_override*/ None,
         ))
@@ -646,6 +650,7 @@ impl ThreadManagerState {
         agent_control: AgentControl,
         session_source: SessionSource,
         inherited_shell_snapshot: Option<Arc<ShellSnapshot>>,
+        inherited_exec_policy: Option<Arc<crate::exec_policy::ExecPolicyManager>>,
     ) -> CodexResult<NewThread> {
         let initial_history = RolloutRecorder::get_rollout_history(&rollout_path).await?;
         Box::pin(self.spawn_thread_with_source(
@@ -658,12 +663,14 @@ impl ThreadManagerState {
             /*persist_extended_history*/ false,
             /*metrics_service_name*/ None,
             inherited_shell_snapshot,
+            inherited_exec_policy,
             /*parent_trace*/ None,
             /*user_shell_override*/ None,
         ))
         .await
     }
 
+    #[allow(clippy::too_many_arguments)]
     pub(crate) async fn fork_thread_with_source(
         &self,
         config: Config,
@@ -672,6 +679,7 @@ impl ThreadManagerState {
         session_source: SessionSource,
         persist_extended_history: bool,
         inherited_shell_snapshot: Option<Arc<ShellSnapshot>>,
+        inherited_exec_policy: Option<Arc<crate::exec_policy::ExecPolicyManager>>,
     ) -> CodexResult<NewThread> {
         Box::pin(self.spawn_thread_with_source(
             config,
@@ -683,6 +691,7 @@ impl ThreadManagerState {
             persist_extended_history,
             /*metrics_service_name*/ None,
             inherited_shell_snapshot,
+            inherited_exec_policy,
             /*parent_trace*/ None,
             /*user_shell_override*/ None,
         ))
@@ -713,6 +722,7 @@ impl ThreadManagerState {
             persist_extended_history,
             metrics_service_name,
             /*inherited_shell_snapshot*/ None,
+            /*inherited_exec_policy*/ None,
             parent_trace,
             user_shell_override,
         ))
@@ -731,6 +741,7 @@ impl ThreadManagerState {
         persist_extended_history: bool,
         metrics_service_name: Option<String>,
         inherited_shell_snapshot: Option<Arc<ShellSnapshot>>,
+        inherited_exec_policy: Option<Arc<crate::exec_policy::ExecPolicyManager>>,
         parent_trace: Option<W3cTraceContext>,
         user_shell_override: Option<crate::shell::Shell>,
     ) -> CodexResult<NewThread> {
@@ -754,6 +765,7 @@ impl ThreadManagerState {
             persist_extended_history,
             metrics_service_name,
             inherited_shell_snapshot,
+            inherited_exec_policy,
             user_shell_override,
             parent_trace,
         })