From fb709bc21f7b226424df7110019447e1870fb24a Mon Sep 17 00:00:00 2001
From: Git'Fellow <12234510+solracsf@users.noreply.github.com>
Date: Wed, 26 Aug 2026 20:27:59 +0200
Subject: [PATCH] fix: Don't apply the ACL wrapper to trash storage on separate
 storages

getBaseStorageForFolderRootJail() skips the ACL wrapper for the trash storage
because the trash backend does its own ACL filtering, but the separate storage
path never got the same guard. createFolder() always uses separate storages
now, so every recently created folder ends up with the wrapper on its trash.

The visible effect is a permanent delete that can never succeed.
ACLStorageWrapper sits below the jail, so it sees the trash paths, and its
unlink() runs canDeleteTree() over them. A deny delete rule follows a file's id
into the trash, so permanently deleting the folder that file was in fails with
"Failed to remove item from trashbin", even though the trash backend already
decided the user is allowed to delete that item.

Signed-off-by: Git'Fellow <12234510+solracsf@users.noreply.github.com>
---
 lib/Mount/FolderStorageManager.php |  3 ++-
 tests/Trash/TrashBackendTest.php   | 24 ++++++++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/lib/Mount/FolderStorageManager.php b/lib/Mount/FolderStorageManager.php
index f2b084911..8cd0f9c63 100644
--- a/lib/Mount/FolderStorageManager.php
+++ b/lib/Mount/FolderStorageManager.php
@@ -109,7 +109,8 @@ private function getBaseStorageForFolderSeparate(
 			$storage = $this->getBaseStorageForFolderSeparateStorageLocal($folderId, $init);
 		}
 
-		if ($folder?->acl && $user) {
+		// apply acl before jail, trash doesn't get the ACL wrapper as it does its own ACL filtering
+		if ($folder?->acl && $user && $type !== 'trash') {
 			$aclManager = $this->aclManagerFactory->getACLManager($user);
 			$storage = new ACLStorageWrapper([
 				'storage' => $storage,
diff --git a/tests/Trash/TrashBackendTest.php b/tests/Trash/TrashBackendTest.php
index 4ab316b7b..384fb684d 100644
--- a/tests/Trash/TrashBackendTest.php
+++ b/tests/Trash/TrashBackendTest.php
@@ -226,6 +226,30 @@ public function testHideDeletedTrashItemInDeletedParentFolderAcl(): void {
 		$this->logout();
 	}
 
+	public function testRemoveTrashedFolderWithRestrictedChild(): void {
+		$this->loginAsUser('manager');
+
+		$folder = $this->managerUserFolder->newFolder("{$this->folderName}/folder");
+		$child = $folder->newFile('file.txt', 'content');
+
+		$this->trashBackend->moveToTrash($folder->getStorage(), $folder->getInternalPath());
+		$this->assertFalse($this->managerUserFolder->nodeExists("{$this->folderName}/folder"));
+
+		// the rule follows the child's file id into the trash, where the storage must not
+		// enforce it: the trash backend does its own ACL filtering
+		$this->ruleManager->saveRule(new Rule(new UserMapping('user', 'manager'), $child->getId(), Constants::PERMISSION_DELETE, 0));
+
+		$items = $this->trashBackend->listTrashRoot($this->managerUser);
+		$this->assertCount(1, $items);
+
+		$this->trashBackend->removeItem($items[0]);
+
+		$this->assertCount(0, $this->trashBackend->listTrashRoot($this->managerUser));
+		$this->assertCount(0, $this->trashManager->listTrashForFolders([$this->folderId]));
+
+		$this->logout();
+	}
+
 	public function testWrongOriginalLocation(): void {
 		$shareManager = Server::get(Share\IManager::class);