Guard against possible overflow bug in NetworkBinaryStream

unresolved3169 · Oct 26, 2018 · 9b820a0 · 9b820a0
1 parent b0624af
commit 9b820a0
Showing 1 changed file with 6 additions and 1 deletion.
diff --git a/src/pocketmine/network/mcpe/NetworkBinaryStream.php b/src/pocketmine/network/mcpe/NetworkBinaryStream.php
@@ -109,7 +109,12 @@ public function putSlot(Item $item) : void{
 		$this->putVarInt($auxValue);
 
 		$nbt = $item->getCompoundTag();
-		$this->putLShort(strlen($nbt));
+		$nbtLen = strlen($nbt);
+		if($nbtLen > 32767){
+			throw new \InvalidArgumentException("NBT encoded length must be < 32768, got $nbtLen bytes");
+		}
+
+		$this->putLShort($nbtLen);
 		$this->put($nbt);
 
 		$this->putVarInt(0); //CanPlaceOn entry count (TODO)