fix(propagator): Lock rows also in propagateChange

Signed-off-by: Carl Schwan <carlschwan@kde.org>
(cherry picked from commit 3d031b0)

Author: CarlSchwan

lib/private/Files/Cache/Propagator.php

@@ -11,6 +11,7 @@
 
 use OC\DB\Exceptions\DbalException;
 use OC\Files\Storage\Wrapper\Encryption;
+use OCP\DB\QueryBuilder\ILiteral;
 use OCP\DB\QueryBuilder\IQueryBuilder;
 use OCP\Files\Cache\IPropagator;
 use OCP\Files\Storage\IReliableEtagStorage;
@@ -63,9 +64,7 @@ public function propagateChange($internalPath, $time, $sizeDifference = 0): void
 		$etag = uniqid(); // since we give all folders the same etag we don't ask the storage for the etag
 
 		$builder = $this->connection->getQueryBuilder();
-		$hashParams = array_map(function ($hash) use ($builder) {
-			return $builder->expr()->literal($hash);
-		}, $parentHashes);
+		$hashParams = array_map(static fn (string $hash): ILiteral => $builder->expr()->literal($hash), $parentHashes);
 
 		$builder->update('filecache')
 			->set('mtime', $builder->func()->greatest('mtime', $builder->createNamedParameter($time, IQueryBuilder::PARAM_INT)))
@@ -106,9 +105,27 @@ public function propagateChange($internalPath, $time, $sizeDifference = 0): void
 
 		for ($i = 0; $i < self::MAX_RETRIES; $i++) {
 			try {
-				$builder->executeStatement();
+				if ($this->connection->getDatabaseProvider() !== IDBConnection::PLATFORM_SQLITE) {
+					$this->connection->beginTransaction();
+					// Lock all the rows first with a SELECT FOR UPDATE ordered by path_hash
+					$forUpdate = $this->connection->getQueryBuilder();
+					$forUpdate->select('fileid')
+						->from('filecache')
+						->where($forUpdate->expr()->eq('storage', $forUpdate->createNamedParameter($storageId, IQueryBuilder::PARAM_INT)))
+						->andWhere($forUpdate->expr()->in('path_hash', $hashParams))
+						->orderBy('path_hash')
+						->forUpdate()
+						->executeQuery();
+					$builder->executeStatement();
+					$this->connection->commit();
+				} else {
+					$builder->executeStatement();
+				}
 				break;
 			} catch (DbalException $e) {
+				if ($this->connection->getDatabaseProvider() !== IDBConnection::PLATFORM_SQLITE) {
+					$this->connection->rollBack();
+				}
 				if (!$e->isRetryable()) {
 					throw $e;
 				}