Fix integer overflow in ChunkingPlugin

Avoids errors when the size exceeds MAX_INT because of the cast to int. Better cast it to float to avoid this.

Signed-off-by: Morris Jobke <hey@morrisjobke.de>

apps/dav/lib/Upload/ChunkingPlugin.php

@@ -97,7 +97,10 @@ class ChunkingPlugin extends ServerPlugin {
 			return;
 		}
 		$actualSize = $this->sourceNode->getSize();
-		if ((int)$expectedSize !== $actualSize) {
+
+		// casted to string because cast to float cause equality for non equal numbers
+		// and integer has the problem of limited size on 32 bit systems
+		if ((string)$expectedSize !== (string)$actualSize) {
 			throw new BadRequest("Chunks on server do not sum up to $expectedSize but to $actualSize bytes");
 		}
 	}