2 files changed, 23 insertions, 4 deletions

diff --git a/lib/private/Files/Utils/PathHelper.php b/lib/private/Files/Utils/PathHelper.php
index a6ae029b957..db1294bcc10 100644
--- a/lib/private/Files/Utils/PathHelper.php
+++ b/lib/private/Files/Utils/PathHelper.php
@@ -37,6 +37,8 @@ class PathHelper {
 		if ($path === '' or $path === '/') {
 			return '/';
 		}
+		// No null bytes
+		$path = str_replace(chr(0), '', $path);
 		//no windows style slashes
 		$path = str_replace('\\', '/', $path);
 		//add leading slash
diff --git a/lib/private/Files/Utils/Scanner.php b/lib/private/Files/Utils/Scanner.php
index bcc54dea0dc..576cb66b3cf 100644
--- a/lib/private/Files/Utils/Scanner.php
+++ b/lib/private/Files/Utils/Scanner.php
@@ -23,11 +23,13 @@ use OCP\Files\Events\FileScannedEvent;
 use OCP\Files\Events\FolderScannedEvent;
 use OCP\Files\Events\NodeAddedToCache;
 use OCP\Files\Events\NodeRemovedFromCache;
+use OCP\Files\Mount\IMountPoint;
 use OCP\Files\NotFoundException;
 use OCP\Files\Storage\IStorage;
 use OCP\Files\StorageNotAvailableException;
 use OCP\IDBConnection;
 use OCP\Lock\ILockingProvider;
+use OCP\Lock\LockedException;
 use Psr\Log\LoggerInterface;
 
 /**
@@ -85,7 +87,7 @@ class Scanner extends PublicEmitter {
 	 * get all storages for $dir
 	 *
 	 * @param string $dir
-	 * @return \OC\Files\Mount\MountPoint[]
+	 * @return array<string, IMountPoint>
 	 */
 	protected function getMounts($dir) {
 		//TODO: move to the node based fileapi once that's done
@@ -96,8 +98,9 @@ class Scanner extends PublicEmitter {
 		$mounts = $mountManager->findIn($dir);
 		$mounts[] = $mountManager->find($dir);
 		$mounts = array_reverse($mounts); //start with the mount of $dir
+		$mountPoints = array_map(fn ($mount) => $mount->getMountPoint(), $mounts);
 
-		return $mounts;
+		return array_combine($mountPoints, $mounts);
 	}
 
 	/**
@@ -106,6 +109,7 @@ class Scanner extends PublicEmitter {
 	 * @param \OC\Files\Mount\MountPoint $mount
 	 */
 	protected function attachListener($mount) {
+		/** @var \OC\Files\Cache\Scanner $scanner */
 		$scanner = $mount->getStorage()->getScanner();
 		$scanner->listen('\OC\Files\Cache\Scanner', 'scanFile', function ($path) use ($mount) {
 			$this->emit('\OC\Files\Utils\Scanner', 'scanFile', [$mount->getMountPoint() . $path]);
@@ -145,6 +149,7 @@ class Scanner extends PublicEmitter {
 					continue;
 				}
 
+				/** @var \OC\Files\Cache\Scanner $scanner */
 				$scanner = $storage->getScanner();
 				$this->attachListener($mount);
 
@@ -200,7 +205,10 @@ class Scanner extends PublicEmitter {
 				foreach (['', 'files'] as $path) {
 					if (!$storage->isCreatable($path)) {
 						$fullPath = $storage->getSourcePath($path);
-						if (!$storage->is_dir($path) && $storage->getCache()->inCache($path)) {
+						if (isset($mounts[$mount->getMountPoint() . $path . '/'])) {
+							// /<user>/files is overwritten by a mountpoint, so this check is irrelevant
+							break;
+						} elseif (!$storage->is_dir($path) && $storage->getCache()->inCache($path)) {
 							throw new NotFoundException("User folder $fullPath exists in cache but not on disk");
 						} elseif ($storage->is_dir($path)) {
 							$ownerUid = fileowner($fullPath);
@@ -221,6 +229,7 @@ class Scanner extends PublicEmitter {
 				continue;
 			}
 			$relativePath = $mount->getInternalPath($dir);
+			/** @var \OC\Files\Cache\Scanner $scanner */
 			$scanner = $storage->getScanner();
 			$scanner->setUseTransactions(false);
 			$this->attachListener($mount);
@@ -252,7 +261,15 @@ class Scanner extends PublicEmitter {
 			try {
 				$propagator = $storage->getPropagator();
 				$propagator->beginBatch();
-				$scanner->scan($relativePath, $recursive, \OC\Files\Cache\Scanner::REUSE_ETAG | \OC\Files\Cache\Scanner::REUSE_SIZE);
+				try {
+					$scanner->scan($relativePath, $recursive, \OC\Files\Cache\Scanner::REUSE_ETAG | \OC\Files\Cache\Scanner::REUSE_SIZE);
+				} catch (LockedException $e) {
+					if (is_string($e->getReadablePath()) && str_starts_with($e->getReadablePath(), 'scanner::')) {
+						throw new LockedException("scanner::$dir", $e, $e->getExistingLock());
+					} else {
+						throw $e;
+					}
+				}
 				$cache = $storage->getCache();
 				if ($cache instanceof Cache) {
 					// only re-calculate for the root folder we scanned, anything below that is taken care of by the scanner