1 files changed, 4 insertions, 28 deletions
diff --git a/src/Agent.Windows/Tools/WindowsToolBackend.cs b/src/Agent.Windows/Tools/WindowsToolBackend.cs
index a21544b..c0d1561 100644
--- a/src/Agent.Windows/Tools/WindowsToolBackend.cs
+++ b/src/Agent.Windows/Tools/WindowsToolBackend.cs
@@ -49,8 +49,10 @@ public sealed class WindowsToolBackend(WindowsSandboxSettings settings, ISecurit
                 // Do not rewrite a file ACL when execute is the only requested capability; CreateProcess remains
                 // constrained by AppContainer access plus canonical path/SHA-256 approval.
                 if (File.Exists(path) && capabilities == FileCapability.Execute) continue;
-                context.Roots.Add(path);
-                foreach (string target in ExistingAclTargets(path)) context.Acls.Add(acl.Grant(taskId, target, capabilities));
+                // A single inheritable ACE on an approved directory covers existing and newly-created
+                // descendants. Snapshotting and rewriting every child ACL is both redundant and
+                // prohibitively expensive for runtime trees such as Python installations.
+                context.Acls.Add(acl.Grant(taskId, path, capabilities));
             }
             IReadOnlyList<NetworkEndpoint> allowances = settings.NetworkMode == "allow"
                 ? await NetworkAllowanceSnapshot.ResolveAsync(settings.NetworkAllowances, cancellationToken).ConfigureAwait(false)
@@ -193,11 +195,6 @@ public sealed class WindowsToolBackend(WindowsSandboxSettings settings, ISecurit
         List<Exception> failures = [];
         try { context.Network?.Dispose(); } catch (Exception ex) { failures.Add(ex); }
         foreach (AclSnapshot snapshot in context.Acls.AsEnumerable().Reverse()) try { context.Acl.Restore(taskId, snapshot); } catch (Exception ex) { failures.Add(ex); }
-        var existingSnapshots = context.Acls.Select(static snapshot => snapshot.Path).ToHashSet(StringComparer.OrdinalIgnoreCase);
-        foreach (string entry in context.Roots.SelectMany(ExistingAclTargets).Distinct(StringComparer.OrdinalIgnoreCase)
-            .Where(entry => !existingSnapshots.Contains(entry))
-            .OrderBy(static entry => entry.Count(character => character == Path.DirectorySeparatorChar)))
-            try { context.Acl.NormalizeNewEntry(taskId, entry); } catch (Exception ex) { failures.Add(ex); }
         if (failures.Count == 0) context.Journal.CompleteAndDelete();
         await Task.CompletedTask;
         if (failures.Count > 0) throw new AggregateException("Task resource cleanup failed.", failures);
@@ -215,26 +212,6 @@ public sealed class WindowsToolBackend(WindowsSandboxSettings settings, ISecurit
         var regex = new Regex(query, RegexOptions.CultureInvariant, TimeSpan.FromSeconds(1));
         return files.Where(path => IsTextMatch(path, regex.IsMatch));
     }
-    private static IEnumerable<string> ExistingAclTargets(string path)
-    {
-        if (File.Exists(path))
-        {
-            yield return path;
-            yield break;
-        }
-        if (!Directory.Exists(path)) yield break;
-        var options = new EnumerationOptions
-        {
-            RecurseSubdirectories = true,
-            IgnoreInaccessible = false,
-            ReturnSpecialDirectories = false,
-            AttributesToSkip = FileAttributes.ReparsePoint
-        };
-        foreach (string entry in Directory.EnumerateFileSystemEntries(path, "*", options)
-            .OrderByDescending(static entry => entry.Count(character => character == Path.DirectorySeparatorChar)))
-            yield return entry;
-        yield return path;
-    }
     private static string ApplyPatch(string path, string patch)
     {
         string current = File.Exists(path) ? File.ReadAllText(path) : string.Empty;
@@ -251,7 +228,6 @@ public sealed class WindowsToolBackend(WindowsSandboxSettings settings, ISecurit
         public TaskResourceJournal Journal { get; } = journal;
         public TaskAclManager Acl { get; } = acl;
         public List<AclSnapshot> Acls { get; } = [];
-        public HashSet<string> Roots { get; } = new(StringComparer.OrdinalIgnoreCase);
         public TaskNetworkPolicy? Network { get; set; }
     }
 }