NVIDIA
diff --git a/‎scripts/nemoclaw-start.sh‎
Lines changed: 52 additions & 4 deletions b/‎scripts/nemoclaw-start.sh‎
Lines changed: 52 additions & 4 deletions
diff --git a/‎test/nemoclaw-start-gateway-health.test.ts‎
Lines changed: 15 additions & 6 deletions b/‎test/nemoclaw-start-gateway-health.test.ts‎
Lines changed: 15 additions & 6 deletions
@@ -4448,9 +4448,7 @@ start_gateway_serving_watchdog() {
       fi
       msg="[gateway-watchdog] CRITICAL: gateway pid $pid is alive but dropped its HTTP listener on port ${_DASHBOARD_PORT} ($refused_streak consecutive refused probes); killing it so the respawn loop can relaunch (#4710)"
       echo "$msg" >&2
-      # _NEMOCLAW_GATEWAY_LOG is a test seam; production always appends to
-      # /tmp/gateway.log alongside the gateway's own output.
-      echo "$msg" >>"${_NEMOCLAW_GATEWAY_LOG:-/tmp/gateway.log}" 2>/dev/null || true
+      append_openclaw_gateway_log_line "$msg" || true
       record_gateway_watchdog_kill "$tracked_identity"
       kill -TERM "$pid" 2>/dev/null || true
       for _ in 1 2 3 4 5 6 7 8 9 10; do
@@ -4796,11 +4794,61 @@ openclaw_runtime_guard_chain_complete() {
   done
 }
 
+append_openclaw_gateway_log_line() {
+  local log_file="/tmp/gateway.log"
+  local line="$1"
+  python3 -I - "$log_file" "$line" <<'PYAPPEND'
+import os
+import stat
+import sys
+
+# Source boundary: production startup owns /tmp/gateway.log creation through
+# _nemoclaw_safe_create_tmp_file before any PID 1 recovery path runs. This
+# permanent defensive append policy never creates the log, never honors an
+# inherited alternate-path environment variable, and refuses link/swap targets
+# before writing recovery breadcrumbs.
+path = sys.argv[1]
+line = sys.argv[2].replace("\r", " ").replace("\n", " ")
+flags = (
+    os.O_WRONLY
+    | os.O_APPEND
+    | getattr(os, "O_CLOEXEC", 0)
+    | getattr(os, "O_NOFOLLOW", 0)
+    | getattr(os, "O_NONBLOCK", 0)
+)
+try:
+    before = os.lstat(path)
+    if not stat.S_ISREG(before.st_mode):
+        print(f"[SECURITY] refusing unsafe gateway log path: {path}", file=sys.stderr)
+        raise SystemExit(1)
+    fd = os.open(path, flags)
+except FileNotFoundError:
+    # Production pre-creates /tmp/gateway.log with _nemoclaw_safe_create_tmp_file.
+    # Do not create it here from a PID 1/root recovery path.
+    raise SystemExit(0)
+except OSError as exc:
+    print(f"[SECURITY] refusing unsafe gateway log path: {path}: {exc}", file=sys.stderr)
+    raise SystemExit(1)
+try:
+    current = os.fstat(fd)
+    if not stat.S_ISREG(current.st_mode) or (current.st_dev, current.st_ino) != (before.st_dev, before.st_ino):
+        print(f"[SECURITY] refusing replaced gateway log path: {path}", file=sys.stderr)
+        raise SystemExit(1)
+    os.write(fd, (line + "\n").encode("utf-8"))
+finally:
+    os.close(fd)
+PYAPPEND
+}
+
 restore_openclaw_runtime_guard_chain() {
   if ! openclaw_runtime_guard_chain_complete; then
     local _guard_warn="[gateway-recovery] WARNING: /tmp guard chain missing or unsafe - restoring library guards from packaged preloads (#2478/#2701)"
     echo "$_guard_warn" >&2
-    echo "$_guard_warn" >>"${_NEMOCLAW_GATEWAY_LOG:-/tmp/gateway.log}" 2>/dev/null || true
+    local _append_rc=0
+    append_openclaw_gateway_log_line "$_guard_warn" || _append_rc=$?
+    if [ "$_append_rc" -ne 0 ] && [ "$_append_rc" -ne 1 ]; then
+      return "$_append_rc"
+    fi
   fi
 
   # Preserve startup ordering: immutable core preloads first, then the
 
@@ -47,6 +47,13 @@ function extractShellFunction(src: string, name: string): string {
   return `${name}() {${body.slice(0, closing?.index ?? 0)}\n}`;
 }
 
+function extractGatewayLogAppendFunction(src: string, gatewayLog: string): string {
+  const functionSource = extractShellFunction(src, "append_openclaw_gateway_log_line");
+  const marker = '  local log_file="/tmp/gateway.log"';
+  expect(functionSource).toContain(marker);
+  return functionSource.replace(marker, `  local log_file=${JSON.stringify(gatewayLog)}`);
+}
+
 function safeTmpHelpers(src: string): string {
   const start = src.indexOf("_nemoclaw_safe_replace_tmp_file() {");
   const end = src.indexOf("_START_LOG=", Math.max(start, 0));
@@ -78,11 +85,12 @@ const writeProcStatFunction = [
   "}",
 ].join("\n");
 
-function watchdogFunctions(): string {
+function watchdogFunctions(gatewayLog: string): string {
   const src = fs.readFileSync(START_SCRIPT, "utf-8");
   return [
     safeTmpHelpers(src),
     pidIdentityFunctions(src),
+    extractGatewayLogAppendFunction(src, gatewayLog),
     extractShellFunction(src, "record_gateway_pid"),
     extractShellFunction(src, "gateway_pid_is_openclaw_gateway"),
     extractShellFunction(src, "gateway_watchdog_positive_int_ok"),
@@ -124,6 +132,7 @@ function runWatchdog(opts: {
   const tmpDir = fs.mkdtempSync(path.join(os.tmpdir(), "nemoclaw-watchdog-"));
   const planFile = path.join(tmpDir, "curl-plan.txt");
   const wedgeLogFile = path.join(tmpDir, "gateway.log");
+  fs.writeFileSync(wedgeLogFile, "", { mode: 0o644 });
   const pidFile = path.join(tmpDir, "gateway.pid");
   const procRoot = path.join(tmpDir, "proc");
   fs.writeFileSync(planFile, `${opts.curlPlan.join("\n")}\n`);
@@ -135,7 +144,7 @@ function runWatchdog(opts: {
     `GATEWAY_PID_FILE=${JSON.stringify(pidFile)}`,
     "_DASHBOARD_PORT=18789",
     `_NEMOCLAW_PROC_ROOT=${JSON.stringify(procRoot)}`,
-    `_NEMOCLAW_GATEWAY_LOG=${JSON.stringify(wedgeLogFile)}`,
+    `_NEMOCLAW_GATEWAY_LOG=${JSON.stringify(path.join(tmpDir, "ignored-inherited.log"))}`,
     writeProcStatFunction,
     // Throttle rather than no-op so the spinning loop stays cheap but the
     // test still completes in well under a second per cycle.
@@ -158,9 +167,7 @@ function runWatchdog(opts: {
     `mkdir -p ${JSON.stringify(procRoot)}/$FAKE_GATEWAY_PID`,
     `printf '%s' ${JSON.stringify(opts.cmdline ?? "openclaw-gateway")} >${JSON.stringify(procRoot)}/$FAKE_GATEWAY_PID/cmdline`,
     `write_proc_stat "$FAKE_GATEWAY_PID" "$$" "$FAKE_GATEWAY_START" >${JSON.stringify(procRoot)}/$FAKE_GATEWAY_PID/stat`,
-    watchdogFunctions(),
-    // The watchdog itself is outside the fake proc fixture. Its launch
-    // identity is irrelevant to these gateway-target tests.
+    watchdogFunctions(wedgeLogFile),
     'capture_openclaw_pid_start_identity() { printf -v "$2" "%s" "watchdog-test"; }',
     'record_gateway_pid "$FAKE_GATEWAY_PID" "$FAKE_GATEWAY_START"',
     "start_gateway_serving_watchdog",
@@ -339,6 +346,8 @@ describe("gateway serving watchdog (#4710)", () => {
     try {
       const planFile = path.join(tmpDir, "curl-plan.txt");
       const probeLog = path.join(tmpDir, "probes.log");
+      const wedgeLogFile = path.join(tmpDir, "gateway.log");
+      fs.writeFileSync(wedgeLogFile, "", { mode: 0o644 });
       const pidFile = path.join(tmpDir, "gateway.pid");
       const procRoot = path.join(tmpDir, "proc");
       // First probe arms on gateway A; everything after refuses.
@@ -380,7 +389,7 @@ describe("gateway serving watchdog (#4710)", () => {
         `printf 'openclaw-gateway' >${JSON.stringify(procRoot)}/$GATEWAY_B/cmdline`,
         `write_proc_stat "$GATEWAY_A" "$$" "$GATEWAY_A_START" >${JSON.stringify(procRoot)}/$GATEWAY_A/stat`,
         `write_proc_stat "$GATEWAY_B" "$$" "$GATEWAY_B_START" >${JSON.stringify(procRoot)}/$GATEWAY_B/stat`,
-        watchdogFunctions(),
+        watchdogFunctions(wedgeLogFile),
         'capture_openclaw_pid_start_identity() { printf -v "$2" "%s" "watchdog-test"; }',
         'record_gateway_pid "$GATEWAY_A" "$GATEWAY_A_START"',
         "start_gateway_serving_watchdog",