diff --git a/tools/environments/docker.py b/tools/environments/docker.py
index aef63e5fd..8748e31a9 100644
--- a/tools/environments/docker.py
+++ b/tools/environments/docker.py
@@ -31,6 +31,9 @@ _SECURITY_ARGS = [
 ]
 
 
+_storage_opt_ok: Optional[bool] = None  # cached result across instances
+
+
 class DockerEnvironment(BaseEnvironment):
     """Hardened Docker container execution with resource limits and persistence.
 
@@ -70,7 +73,7 @@ class DockerEnvironment(BaseEnvironment):
             resource_args.extend(["--cpus", str(cpu)])
         if memory > 0:
             resource_args.extend(["--memory", f"{memory}m"])
-        if disk > 0 and sys.platform != "darwin":
+        if disk > 0 and sys.platform != "darwin" and self._storage_opt_supported():
             resource_args.extend(["--storage-opt", f"size={disk}m"])
         if not network:
             resource_args.append("--network=none")
@@ -110,6 +113,45 @@ class DockerEnvironment(BaseEnvironment):
         )
         self._container_id = self._inner.container_id
 
+    @staticmethod
+    def _storage_opt_supported() -> bool:
+        """Check if Docker's storage driver supports --storage-opt size=.
+        
+        Only overlay2 on XFS with pquota supports per-container disk quotas.
+        Ubuntu (and most distros) default to ext4, where this flag errors out.
+        """
+        global _storage_opt_ok
+        if _storage_opt_ok is not None:
+            return _storage_opt_ok
+        try:
+            result = subprocess.run(
+                ["docker", "info", "--format", "{{.Driver}}"],
+                capture_output=True, text=True, timeout=10,
+            )
+            driver = result.stdout.strip().lower()
+            if driver != "overlay2":
+                _storage_opt_ok = False
+                return False
+            # overlay2 only supports storage-opt on XFS with pquota.
+            # Probe by attempting a dry-ish run — the fastest reliable check.
+            probe = subprocess.run(
+                ["docker", "create", "--storage-opt", "size=1m", "hello-world"],
+                capture_output=True, text=True, timeout=15,
+            )
+            if probe.returncode == 0:
+                # Clean up the created container
+                container_id = probe.stdout.strip()
+                if container_id:
+                    subprocess.run(["docker", "rm", container_id],
+                                   capture_output=True, timeout=5)
+                _storage_opt_ok = True
+            else:
+                _storage_opt_ok = False
+        except Exception:
+            _storage_opt_ok = False
+        logger.debug("Docker --storage-opt support: %s", _storage_opt_ok)
+        return _storage_opt_ok
+
     def execute(self, command: str, cwd: str = "", *,
                 timeout: int | None = None,
                 stdin_data: str | None = None) -> dict: