CB-192: fix false credential-gap WARN under allow-list+zsh, split its log guard

logCredentialGap(creds) always emitted the WARN wording ("every member pane
inherits them UNBLOCKED"), even under memberCredentials.policy: allow-list on
a zsh login shell, where the generated ZDOTDIR scrub genuinely blanks the
name. The line reported the control working as though it were a hole.

Pass an effectiveAllowed set instead: null keeps the WARN (deny-by-default,
and the allow-list non-zsh fallback, where nothing is ever scrubbed); the
derived allow-list set (only reachable after applyEnvironmentAllowListPolicy's
own zsh gate) selects a new INFO wording that says the scrub will blank the
name instead of claiming it is inherited unblocked.

Also split the single credentialGapLogged AtomicBoolean into two guards
(unprotectedGapLogged / allowListGapLogged) — one per report kind. Since
memberCredentials is a live, re-read-per-spawn supplier, a shared flag let a
harmless allow-list INFO on one spawn permanently suppress a later spawn's
real deny-by-default WARN after a policy reload.

Fixes gitea #192.

fleetd/src/main/java/dev/ltms/fleet/member/HerdrPeerLauncher.java

@@ -1008,6 +1008,13 @@ public abstract class HerdrPeerLauncher implements PeerLauncher {
      * applied before the login shell runs and a sourced file can (and did) undo it. The control is
      * the ZDOTDIR scrub ({@link #applyEnvironmentAllowListPolicy}); {@code known}/{@code allow}
      * remain as reporting only via {@link #logCredentialGap}.
+     *
+     * <p>CB-633 follow-up (#192): under {@code allow-list} this method does NOT call {@link
+     * #logCredentialGap} itself — at this point (called from {@link #baseEnv}, before {@link
+     * #applyEnvironmentAllowListPolicy} runs) we do not yet know whether the pane's shell is zsh, so
+     * we cannot yet pick correct wording. That decision, and the call, are deferred entirely to
+     * {@link #applyEnvironmentAllowListPolicy}, which knows by then whether the scrub will actually
+     * run.
      */
     private void applyMemberCredentialPolicy(Map<String, String> workerEnv) {
         FleetConfig.MemberCredentials creds = memberCredentials == null ? null : memberCredentials.get();
@@ -1016,8 +1023,8 @@ public abstract class HerdrPeerLauncher implements PeerLauncher {
         }
         if (!creds.isAllowList()) {
             overlayBlockedCredentials(workerEnv, creds);
+            logCredentialGap(creds, null);
         }
-        logCredentialGap(creds);
     }
 
     /** Put {@link #BLOCKED_CREDENTIAL_SENTINEL} over every blocked name in the pane-creation env map. */
@@ -1067,12 +1074,15 @@ public abstract class HerdrPeerLauncher implements PeerLauncher {
             // logCredentialGap's WARN (below) is the only signal for this path.
             warnNonZsh(loginShell);
             overlayBlockedCredentials(launch.env(), creds);
-            logCredentialGap(creds);
+            logCredentialGap(creds, null);
             return null;
         }
         // Only reached when the scrub is actually about to run — the count below describes that
-        // scrub, so it must not be logged before this gate (see the non-zsh branch above).
+        // scrub, so it must not be logged before this gate (see the non-zsh branch above). Same
+        // reasoning gates logCredentialGap's wording: passing the derived `allowed` set (non-null)
+        // here, and ONLY here, is what tells it the scrub will really blank an unkept name — #192.
         logAllowListCoverage(allowed);
+        logCredentialGap(creds, allowed);
         Path dir = EnvAllowListScrub.generate(Path.of(System.getProperty("java.io.tmpdir")), allowed);
         launch.env().put("ZDOTDIR", dir.toAbsolutePath().toString());
         log.info("memberCredentials policy=allow-list: profile={} generated ZDOTDIR {} — derived "
@@ -1177,18 +1187,46 @@ public abstract class HerdrPeerLauncher implements PeerLauncher {
     private static final Pattern CREDENTIAL_SHAPED_NAME =
             Pattern.compile("(?i).*(TOKEN|SECRET|_KEY|APIKEY|PASSWORD|CREDENTIAL|AUTH).*");
 
-    /** Guards {@link #logCredentialGap} to one WARN per launcher instance, not one per spawn. */
-    private final AtomicBoolean credentialGapLogged = new AtomicBoolean();
+    /**
+     * Guards the {@code effectiveAllowed == null} branch of {@link #logCredentialGap} — the
+     * genuinely-unprotected report (deny-by-default, and the allow-list non-zsh fallback) — to one
+     * WARN per launcher instance, not one per spawn.
+     *
+     * <p>CB-633 follow-up (#192): kept SEPARATE from {@link #allowListGapLogged} on purpose.
+     * {@code memberCredentials} is a live, re-read-per-spawn supplier, so the policy can change
+     * between two spawns on the same launcher. A single shared flag would let a harmless allow-list
+     * INFO on spawn 1 permanently suppress the real deny-by-default WARN a later spawn deserves —
+     * the report that matters most getting hidden by the report that doesn't. Two flags mean each
+     * report kind fires exactly once, independent of what the other kind already logged.
+     */
+    private final AtomicBoolean unprotectedGapLogged = new AtomicBoolean();
+
+    /**
+     * Guards the {@code effectiveAllowed != null} branch of {@link #logCredentialGap} — the
+     * allow-list-scrub-covered report — to one INFO per launcher instance. See {@link
+     * #unprotectedGapLogged}'s javadoc for why this is a separate flag rather than a shared one.
+     */
+    private final AtomicBoolean allowListGapLogged = new AtomicBoolean();
 
     /**
      * CB-596 criterion 4: a credential-shaped host env var name on neither {@code known} nor
      * {@code allow} is not silently allowed — it is reported. {@link #hostEnvNames} enumerates the
      * daemon's own environment (see that field's javadoc for why the daemon's env is read rather
      * than the spawned pane's, which the daemon has no channel to inspect at spawn time); this logs
-     * every such NAME, at WARN, at most once per launcher instance — never a value, a prefix of a
-     * value, or a hash of a value, so the log itself cannot leak anything.
+     * every such NAME — never a value, a prefix of a value, or a hash of a value, so the log itself
+     * cannot leak anything.
+     *
+     * <p>CB-633 follow-up (#192): {@code effectiveAllowed} picks the wording, and it must NOT be
+     * picked from {@code creds.isAllowList()} — see {@link #applyEnvironmentAllowListPolicy}'s
+     * javadoc for the reasoning this mirrors. {@code null} means no scrub-derived allow-list was
+     * computed for this call — true on the deny-by-default path AND on the allow-list non-zsh
+     * fallback, where nothing is ever scrubbed — so the gap is real and gets the WARN, unchanged
+     * from before this fix. Non-null means this call came from the zsh branch of {@link
+     * #applyEnvironmentAllowListPolicy}, reachable ONLY after that method's own zsh gate — so the
+     * generated scrub genuinely will blank these names, and the INFO says so instead of claiming
+     * they are inherited unblocked.
      */
-    private void logCredentialGap(FleetConfig.MemberCredentials creds) {
+    private void logCredentialGap(FleetConfig.MemberCredentials creds, Set<String> effectiveAllowed) {
         Set<String> covered = new HashSet<>(creds.known());
         covered.addAll(creds.allow());
         List<String> gap = hostEnvNames.get().stream()
@@ -1199,7 +1237,17 @@ public abstract class HerdrPeerLauncher implements PeerLauncher {
         if (gap.isEmpty()) {
             return;
         }
-        if (credentialGapLogged.compareAndSet(false, true)) {
+        if (effectiveAllowed != null) {
+            if (allowListGapLogged.compareAndSet(false, true)) {
+                log.info("memberCredentials gap: {} credential-shaped env var name(s) are on neither "
+                                + "known: nor allow: — {}. The allow-list scrub blanks them anyway (they "
+                                + "are not on the derived allow-list), so no member pane keeps them; add "
+                                + "each to memberCredentials.known or .allow to make that explicit.",
+                        gap.size(), gap);
+            }
+            return;
+        }
+        if (unprotectedGapLogged.compareAndSet(false, true)) {
             log.warn("memberCredentials gap: {} credential-shaped env var name(s) are on neither "
                             + "known: nor allow: — every member pane inherits them UNBLOCKED — {}. "
                             + "Add each to memberCredentials.known (blocked by default) or .allow "

fleetd/src/test/java/dev/ltms/fleet/member/ClaudeCodeLauncherTest.java

@@ -1,5 +1,6 @@
 package dev.ltms.fleet.member;
 
+import ch.qos.logback.classic.Level;
 import ch.qos.logback.classic.Logger;
 import ch.qos.logback.classic.spi.ILoggingEvent;
 import ch.qos.logback.core.read.ListAppender;
@@ -1055,6 +1056,186 @@ class ClaudeCodeLauncherTest {
                 "a name already on allow: is covered, not a gap");
     }
 
+    /**
+     * CB-633 follow-up (#192): the deny-by-default WARN wording is a promise an operator relies on —
+     * pinned byte-for-byte so a future edit cannot drift it (e.g. while picking wording for the
+     * allow-list path) without a test noticing.
+     */
+    @Test
+    void denyByDefaultKeepsTheExactCredentialGapWarn() {
+        FakeHerdr herdr = new FakeHerdr();
+        FleetConfig.Profile cfg = new FleetConfig.Profile(
+                "ltms-local", "http://gx00.gw:8000", "coder", null, "FLEETD_WORKER_TOKEN",
+                List.of("claude"), "tab", "fleetd-workers", "worker: {profile} #{n}", null, null, null);
+        ClaudeCodeLauncher svc = new ClaudeCodeLauncher(new AgentControl(herdr), new WorkspaceControl(herdr),
+                new SubscriptionGuard(Set.of("gx00.gw")), Map.of(cfg.profile(), cfg), cfg.profile(),
+                _ -> null, 0, System::currentTimeMillis, () -> {}, null, () -> TEST_MEMBER_CREDENTIALS,
+                () -> Set.of("A_BRAND_NEW_SECRET_TOKEN"));
+
+        Logger logger = (Logger) LoggerFactory.getLogger(HerdrPeerLauncher.class);
+        ListAppender<ILoggingEvent> appender = new ListAppender<>();
+        appender.start();
+        logger.addAppender(appender);
+        try {
+            svc.spawn();
+        } finally {
+            logger.detachAppender(appender);
+        }
+
+        assertTrue(appender.list.stream().anyMatch(e ->
+                        ("memberCredentials gap: 1 credential-shaped env var name(s) are on neither "
+                                + "known: nor allow: — every member pane inherits them UNBLOCKED — "
+                                + "[A_BRAND_NEW_SECRET_TOKEN]. Add each to memberCredentials.known "
+                                + "(blocked by default) or .allow (if a member legitimately needs it).")
+                                .equals(e.getFormattedMessage())),
+                "the deny-by-default WARN text must not drift — got: "
+                        + appender.list.stream().map(ILoggingEvent::getFormattedMessage).toList());
+    }
+
+    /**
+     * CB-633 follow-up (#192), defect 1: under {@code policy: allow-list} on a zsh login shell the
+     * generated ZDOTDIR scrub genuinely blanks an unkept credential-shaped name, so the report must
+     * not say the pane inherits it UNBLOCKED — that claim is exactly what PR #174 got wrong. This
+     * goes through the real spawn path (not {@code HerdrPeerLauncherAllowListWiringTest}'s fixture,
+     * which overrides {@code buildLaunch} and bypasses none of the logic under test here — the
+     * shell-dependent branch lives in {@code applyEnvironmentAllowListPolicy}, which every spawn
+     * still passes through).
+     */
+    @Test
+    void allowListPolicyOnZshReportsTheGapWithoutClaimingItIsUnblocked() {
+        FakeHerdr herdr = new FakeHerdr();
+        FleetConfig.Profile cfg = new FleetConfig.Profile(
+                "ltms-local", "http://gx00.gw:8000", "coder", null, "FLEETD_WORKER_TOKEN",
+                List.of("claude"), "tab", "fleetd-workers", "worker: {profile} #{n}", null, null, null);
+        FleetConfig.MemberCredentials creds = new FleetConfig.MemberCredentials(
+                FleetConfig.MemberCredentials.POLICY_ALLOW_LIST,
+                List.of("AI_GATEWAY_TOKEN"), List.of());
+        ClaudeCodeLauncher svc = new ClaudeCodeLauncher(new AgentControl(herdr), new WorkspaceControl(herdr),
+                new SubscriptionGuard(Set.of("gx00.gw")), Map.of(cfg.profile(), cfg), cfg.profile(),
+                name -> "SHELL".equals(name) ? "/bin/zsh" : null,
+                0, System::currentTimeMillis, () -> {}, null, () -> creds,
+                () -> Set.of("AI_GATEWAY_TOKEN", "A_BRAND_NEW_SECRET_TOKEN"));
+
+        Logger logger = (Logger) LoggerFactory.getLogger(HerdrPeerLauncher.class);
+        Level original = logger.getLevel();
+        logger.setLevel(Level.INFO);
+        ListAppender<ILoggingEvent> appender = new ListAppender<>();
+        appender.start();
+        logger.addAppender(appender);
+        try {
+            svc.spawn();
+        } finally {
+            logger.detachAppender(appender);
+            logger.setLevel(original);
+        }
+
+        assertTrue(appender.list.stream().anyMatch(e ->
+                        e.getFormattedMessage().contains("memberCredentials gap")
+                                && e.getFormattedMessage().contains("A_BRAND_NEW_SECRET_TOKEN")),
+                "the unkept name must still be reported — got: "
+                        + appender.list.stream().map(ILoggingEvent::getFormattedMessage).toList());
+        assertFalse(appender.list.stream().anyMatch(e ->
+                        e.getFormattedMessage().contains("memberCredentials gap")
+                                && e.getFormattedMessage().contains("UNBLOCKED")),
+                "on zsh the scrub genuinely blanks the name, so the report must not claim it is "
+                        + "inherited unblocked — got: "
+                        + appender.list.stream().map(ILoggingEvent::getFormattedMessage).toList());
+    }
+
+    /**
+     * CB-633 follow-up (#192): the mirror of the zsh test above. On a non-zsh login shell {@code
+     * ZDOTDIR} is ignored, so no scrub ever runs — the report must keep the WARN wording (a name here
+     * really is inherited unblocked) rather than claiming a scrub protects it. This is the trap PR
+     * #174 fell into the other direction: keying the wording on the shell, not on {@code
+     * creds.isAllowList()}, is what keeps this branch correct.
+     */
+    @Test
+    void allowListPolicyOnNonZshKeepsTheWarnWording() {
+        FakeHerdr herdr = new FakeHerdr();
+        FleetConfig.Profile cfg = new FleetConfig.Profile(
+                "ltms-local", "http://gx00.gw:8000", "coder", null, "FLEETD_WORKER_TOKEN",
+                List.of("claude"), "tab", "fleetd-workers", "worker: {profile} #{n}", null, null, null);
+        FleetConfig.MemberCredentials creds = new FleetConfig.MemberCredentials(
+                FleetConfig.MemberCredentials.POLICY_ALLOW_LIST,
+                List.of("AI_GATEWAY_TOKEN"), List.of());
+        ClaudeCodeLauncher svc = new ClaudeCodeLauncher(new AgentControl(herdr), new WorkspaceControl(herdr),
+                new SubscriptionGuard(Set.of("gx00.gw")), Map.of(cfg.profile(), cfg), cfg.profile(),
+                name -> "SHELL".equals(name) ? "/bin/bash" : null,
+                0, System::currentTimeMillis, () -> {}, null, () -> creds,
+                () -> Set.of("AI_GATEWAY_TOKEN", "A_BRAND_NEW_SECRET_TOKEN"));
+
+        Logger logger = (Logger) LoggerFactory.getLogger(HerdrPeerLauncher.class);
+        ListAppender<ILoggingEvent> appender = new ListAppender<>();
+        appender.start();
+        logger.addAppender(appender);
+        try {
+            svc.spawn();
+        } finally {
+            logger.detachAppender(appender);
+        }
+
+        assertTrue(appender.list.stream().anyMatch(e ->
+                        e.getFormattedMessage().contains("memberCredentials gap")
+                                && e.getFormattedMessage().contains("UNBLOCKED")
+                                && e.getFormattedMessage().contains("A_BRAND_NEW_SECRET_TOKEN")),
+                "no scrub runs on a non-zsh shell, so the WARN wording must be kept — got: "
+                        + appender.list.stream().map(ILoggingEvent::getFormattedMessage).toList());
+        assertFalse(appender.list.stream().anyMatch(e ->
+                        e.getFormattedMessage().contains("memberCredentials gap")
+                                && e.getFormattedMessage().toLowerCase(java.util.Locale.ROOT).contains("scrub")),
+                "nothing is scrubbed on this path, so the report must not claim otherwise — got: "
+                        + appender.list.stream().map(ILoggingEvent::getFormattedMessage).toList());
+    }
+
+    /**
+     * CB-633 follow-up (#192), defect 2: {@code memberCredentials} is a live, re-read-per-spawn
+     * supplier, so the policy can change between two spawns on the same launcher. Before this fix a
+     * single {@code AtomicBoolean} guarded both report kinds, so the harmless allow-list INFO on the
+     * first spawn would permanently suppress the real deny-by-default WARN a later spawn deserves.
+     * This goes through {@link ClaudeCodeLauncher#buildLaunch}'s real {@code baseEnv()} path — the
+     * WARN this test pins fires from {@code applyMemberCredentialPolicy}, which {@code
+     * HerdrPeerLauncherAllowListWiringTest}'s fixture never reaches at all (see its class javadoc).
+     */
+    @Test
+    void secondSpawnStillWarnsAfterPolicyChangesFromAllowListToDenyByDefault() {
+        FakeHerdr herdr = new FakeHerdr();
+        FleetConfig.Profile cfg = new FleetConfig.Profile(
+                "ltms-local", "http://gx00.gw:8000", "coder", null, "FLEETD_WORKER_TOKEN",
+                List.of("claude"), "tab", "fleetd-workers", "worker: {profile} #{n}", null, null, null);
+        AtomicReference<FleetConfig.MemberCredentials> creds = new AtomicReference<>(
+                new FleetConfig.MemberCredentials(FleetConfig.MemberCredentials.POLICY_ALLOW_LIST,
+                        List.of("AI_GATEWAY_TOKEN"), List.of()));
+        ClaudeCodeLauncher svc = new ClaudeCodeLauncher(new AgentControl(herdr), new WorkspaceControl(herdr),
+                new SubscriptionGuard(Set.of("gx00.gw")), Map.of(cfg.profile(), cfg), cfg.profile(),
+                name -> "SHELL".equals(name) ? "/bin/zsh" : null,
+                0, System::currentTimeMillis, () -> {}, null, creds::get,
+                () -> Set.of("AI_GATEWAY_TOKEN", "A_BRAND_NEW_SECRET_TOKEN"));
+
+        Logger logger = (Logger) LoggerFactory.getLogger(HerdrPeerLauncher.class);
+        Level original = logger.getLevel();
+        logger.setLevel(Level.INFO);
+        ListAppender<ILoggingEvent> appender = new ListAppender<>();
+        appender.start();
+        try {
+            logger.addAppender(appender);
+            svc.spawn(); // allow-list + zsh: harmless INFO, sets the allow-list guard only
+
+            creds.set(new FleetConfig.MemberCredentials(FleetConfig.MemberCredentials.POLICY_DENY_BY_DEFAULT,
+                    List.of("AI_GATEWAY_TOKEN"), List.of()));
+            svc.spawn(); // policy reloaded to deny-by-default: this WARN must NOT be suppressed
+        } finally {
+            logger.detachAppender(appender);
+            logger.setLevel(original);
+        }
+
+        assertTrue(appender.list.stream().anyMatch(e ->
+                        e.getFormattedMessage().contains("memberCredentials gap")
+                                && e.getFormattedMessage().contains("UNBLOCKED")),
+                "the second spawn's deny-by-default WARN must still fire even though the first "
+                        + "spawn's allow-list INFO already logged the same underlying gap — got: "
+                        + appender.list.stream().map(ILoggingEvent::getFormattedMessage).toList());
+    }
+
     /**
      * The half of CB-592 that can actually survive the pane's login shell. BRIDGED_MEMBER is a name
      * secrets.sh never exports, so nothing overwrites it — measured: GITEA_TOKEN is injected the