From 72150d6deb896e0191c2920fdb72744ae6fbb341 Mon Sep 17 00:00:00 2001
From: Robin Appelman <robin@icewind.nl>
Date: Fri, 30 Jan 2026 17:38:56 +0100
Subject: [PATCH] fix: getById: don't setup for all users with access by
 default

Signed-off-by: Robin Appelman <robin@icewind.nl>
---
 lib/private/Files/Mount/Manager.php |  4 +--
 lib/private/Files/Node/Root.php     | 42 ++++++++++++++++++++++-------
 2 files changed, 34 insertions(+), 12 deletions(-)

diff --git a/lib/private/Files/Mount/Manager.php b/lib/private/Files/Mount/Manager.php
index b763697387d..72b38f38575 100644
--- a/lib/private/Files/Mount/Manager.php
+++ b/lib/private/Files/Mount/Manager.php
@@ -230,11 +230,11 @@ class Manager implements IMountManager {
 	}
 
 	/**
-	 * Return all mounts in a path from a specific mount provider
+	 * Return all mounts in a path from a specific mount provider, indexed by mount point
 	 *
 	 * @param string $path
 	 * @param string[] $mountProviders
-	 * @return IMountPoint[]
+	 * @return array<string, IMountPoint>
 	 */
 	public function getMountsByMountProvider(string $path, array $mountProviders) {
 		$this->getSetupManager()->setupForProvider($path, $mountProviders);
diff --git a/lib/private/Files/Node/Root.php b/lib/private/Files/Node/Root.php
index c94eadcedb3..8354f382aa3 100644
--- a/lib/private/Files/Node/Root.php
+++ b/lib/private/Files/Node/Root.php
@@ -5,6 +5,7 @@
  * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
  * SPDX-License-Identifier: AGPL-3.0-only
  */
+
 namespace OC\Files\Node;
 
 use OC\Files\FileInfo;
@@ -19,6 +20,8 @@ use OCA\Files\ConfigLexicon;
 use OCP\Cache\CappedMemoryCache;
 use OCP\EventDispatcher\IEventDispatcher;
 use OCP\Files\Cache\ICacheEntry;
+use OCP\Files\Config\ICachedMountFileInfo;
+use OCP\Files\Config\ICachedMountInfo;
 use OCP\Files\Config\IUserMountCache;
 use OCP\Files\Events\Node\FilesystemTornDownEvent;
 use OCP\Files\IRootFolder;
@@ -82,10 +85,8 @@ class Root extends Folder implements IRootFolder {
 
 	/**
 	 * Get the user for which the filesystem is setup
-	 *
-	 * @return \OC\User\User
 	 */
-	public function getUser() {
+	public function getUser(): ?IUser {
 		return $this->user;
 	}
 
@@ -411,12 +412,12 @@ class Root extends Folder implements IRootFolder {
 		} else {
 			$user = null;
 		}
-		$mountsContainingFile = $mountCache->getMountsForFileId($id, $user);
+		$mountInfosContainingFiles = $mountCache->getMountsForFileId($id, $user);
 
 		// if the mount isn't in the cache yet, perform a setup first, then try again
-		if (count($mountsContainingFile) === 0) {
+		if (count($mountInfosContainingFiles) === 0) {
 			$setupManager->setupForPath($path, true);
-			$mountsContainingFile = $mountCache->getMountsForFileId($id, $user);
+			$mountInfosContainingFiles = $mountCache->getMountsForFileId($id, $user);
 		}
 
 		// when a user has access through the same storage through multiple paths
@@ -428,16 +429,37 @@ class Root extends Folder implements IRootFolder {
 
 		$mountRootIds = array_map(function ($mount) {
 			return $mount->getRootId();
-		}, $mountsContainingFile);
+		}, $mountInfosContainingFiles);
 		$mountRootPaths = array_map(function ($mount) {
 			return $mount->getRootInternalPath();
-		}, $mountsContainingFile);
+		}, $mountInfosContainingFiles);
 		$mountProviders = array_unique(array_map(function ($mount) {
 			return $mount->getMountProvider();
-		}, $mountsContainingFile));
+		}, $mountInfosContainingFiles));
+		$mountPoints = array_map(fn (ICachedMountInfo $mountInfo) => $mountInfo->getMountPoint(), $mountInfosContainingFiles);
 		$mountRoots = array_combine($mountRootIds, $mountRootPaths);
 
-		$mountsContainingFile = array_filter(array_map($this->mountManager->getMountFromMountInfo(...), $mountsContainingFile));
+		$mounts = $this->mountManager->getMountsByMountProvider($path, $mountProviders);
+		$mountsContainingFile = array_filter($mounts, fn (IMountPoint $mount) => in_array($mount->getMountPoint(), $mountPoints));
+
+		// if we haven't found a relevant mount that is setup, but we do have relevant mount infos
+		// we try to load them from the mount info.
+		if (count($mountsContainingFile) === 0 && count($mountInfosContainingFiles) > 0) {
+			// in order to minimize the cost of this, we only use the mount infos from one user.
+			if (!$user) {
+				// if we don't have a user from the path, use the user from the current filesystem setup
+				$user = $this->getUser()?->getUID();
+			}
+			if (!$user) {
+				// if there also isn't a current filesystem user, just use the user from the first mount info
+				/** @var ICachedMountFileInfo $firstMount */
+				$firstMount = current($mountInfosContainingFiles);
+				$user = $firstMount->getUser()->getUID();
+			}
+			// get the mount infos for the user we picked, and get the mounts for it
+			$mountInfosContainingFiles = array_filter($mountInfosContainingFiles, fn (ICachedMountInfo $mountInfo) => $mountInfo->getUser()->getUID() === $user);
+			$mountsContainingFile = array_filter(array_map($this->mountManager->getMountFromMountInfo(...), $mountInfosContainingFiles));
+		}
 
 		if (count($mountsContainingFile) === 0) {
 			if ($user === $this->getAppDataDirectoryName()) {