From fbef9b7df6ee72bd663e50d126d4c4e99f34ac4b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Baki=20Burak=20=C3=96=C4=9F=C3=BCn?=
 <63836730+bakiburakogun@users.noreply.github.com>
Date: Sun, 23 Aug 2026 03:24:33 +0300
Subject: [PATCH] fix(files_sharing): don't crash CleanupShareTarget when mount
 info is missing
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The repair step "Cleanup share names with false conflicts" fatals with
"Call to a member function getRootId() on null" when a problem share's
old target has no entry in the recipient's cached mounts (e.g. the
recipient has not logged in since the share was created).

Guard the lookup the same way the generateUniqueTarget callback already
does and skip the mount cache refresh in that case - the share row is
already updated by moveShare() and the cache is rebuilt on the user's
next login.

Fixes #63494

Signed-off-by: Baki Burak Öğün <63836730+bakiburakogun@users.noreply.github.com>
---
 .../lib/Repair/CleanupShareTarget.php         | 22 ++++++++++---------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/apps/files_sharing/lib/Repair/CleanupShareTarget.php b/apps/files_sharing/lib/Repair/CleanupShareTarget.php
index 368dcfc74b7a3..967da564c8611 100644
--- a/apps/files_sharing/lib/Repair/CleanupShareTarget.php
+++ b/apps/files_sharing/lib/Repair/CleanupShareTarget.php
@@ -118,16 +118,18 @@ public function run(IOutput $output) {
 					$oldMountPoint = "/{$recipient->getUID()}/files$oldTarget/";
 					$newMountPoint = "/{$recipient->getUID()}/files$newTarget/";
 
-					/** @var ICachedMountInfo $mount */
-					$mount = $userMounts[$oldMountPoint];
-					$userMounts[$newMountPoint] = $mount;
-					unset($userMounts[$oldMountPoint]);
-
-					$this->userMountCache->removeMount($oldMountPoint);
-					$this->userMountCache->addMount($recipient, $newMountPoint, new CacheEntry([
-						'fileid' => $mount->getRootId(),
-						'storage' => $mount->getStorageId(),
-					]), $mount->getMountProvider(), $mount->getMountId());
+					/** @var ICachedMountInfo|null $mount */
+					$mount = $userMounts[$oldMountPoint] ?? null;
+					if ($mount !== null) {
+						$userMounts[$newMountPoint] = $mount;
+						unset($userMounts[$oldMountPoint]);
+
+						$this->userMountCache->removeMount($oldMountPoint);
+						$this->userMountCache->addMount($recipient, $newMountPoint, new CacheEntry([
+							'fileid' => $mount->getRootId(),
+							'storage' => $mount->getStorageId(),
+						]), $mount->getMountProvider(), $mount->getMountId());
+					}
 				}
 			} catch (\Exception $e) {
 				$msg = 'error cleaning up share target: ' . $e->getMessage();