From de536f49cb6ab313a2cd64db78bac4f58e46cf76 Mon Sep 17 00:00:00 2001 From: moneromooo-monero Date: Sat, 9 Mar 2019 09:08:53 +0000 Subject: [PATCH] cryptonote_protocol: fix another potential P2P DoS When asking for txes in a fluffy transaction, one might ask for the same (large) tx many times --- .../cryptonote_protocol_handler.inl | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/src/cryptonote_protocol/cryptonote_protocol_handler.inl b/src/cryptonote_protocol/cryptonote_protocol_handler.inl index 3e44310dd..399441b0e 100644 --- a/src/cryptonote_protocol/cryptonote_protocol_handler.inl +++ b/src/cryptonote_protocol/cryptonote_protocol_handler.inl @@ -809,12 +809,27 @@ namespace cryptonote NOTIFY_NEW_FLUFFY_BLOCK::request fluffy_response; fluffy_response.b.block = t_serializable_object_to_blob(b); fluffy_response.current_blockchain_height = arg.current_blockchain_height; + std::vector seen(b.tx_hashes.size(), false); for(auto& tx_idx: arg.missing_tx_indices) { if(tx_idx < b.tx_hashes.size()) { MDEBUG(" tx " << b.tx_hashes[tx_idx]); + if (seen[tx_idx]) + { + LOG_ERROR_CCONTEXT + ( + "Failed to handle request NOTIFY_REQUEST_FLUFFY_MISSING_TX" + << ", request is asking for duplicate tx " + << ", tx index = " << tx_idx << ", block tx count " << b.tx_hashes.size() + << ", block_height = " << arg.current_blockchain_height + << ", dropping connection" + ); + drop_connection(context, true, false); + return 1; + } txids.push_back(b.tx_hashes[tx_idx]); + seen[tx_idx] = true; } else {