From 972530f3a74a4297263f23783a13dde7a8e176a2 Mon Sep 17 00:00:00 2001
From: Exynox <exynox@old-metin2.com>
Date: Sun, 27 Nov 2022 10:46:56 +0200
Subject: [PATCH] Fixed serious issue where oversized packets would be split
 apart by libevent without proper handling by the db core. Removed Google
 Sanitizers

---
 db/CMakeLists.txt   |  3 ---
 db/src/Peer.cpp     | 20 +++++++++++++++++++-
 game/CMakeLists.txt |  1 -
 3 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/db/CMakeLists.txt b/db/CMakeLists.txt
index b41f783..f9307a2 100644
--- a/db/CMakeLists.txt
+++ b/db/CMakeLists.txt
@@ -26,6 +26,3 @@ find_package(Libevent CONFIG REQUIRED)
 target_link_libraries(${PROJECT_NAME} PRIVATE libevent::core libevent::extra libevent::pthreads)
 
 target_link_libraries(${PROJECT_NAME} PRIVATE libpoly libsql libthecore)
-
-# Memory debugging
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fsanitize=address -g")
diff --git a/db/src/Peer.cpp b/db/src/Peer.cpp
index 8b2292e..1801102 100644
--- a/db/src/Peer.cpp
+++ b/db/src/Peer.cpp
@@ -63,12 +63,19 @@ void CPeer::SetUserCount(DWORD dwCount)
 
 bool CPeer::PeekPacket(int & iBytesProceed, BYTE & header, DWORD & dwHandle, DWORD & dwLength, const char ** data)
 {
+    // Return if not enough data was received to read the header
 	if (GetRecvLength() < iBytesProceed + 9)
 		return false;
 
 	const char * buf = (const char *) GetRecvBuffer(iBytesProceed + 9);
+    if (!buf) {
+        sys_err("PeekPacket: Failed to get network buffer!");
+        return false;
+    }
+
 	buf += iBytesProceed;
 
+    // Read the header data
 	header	= *(buf++);
 
 	dwHandle	= *((DWORD *) buf);
@@ -77,7 +84,7 @@ bool CPeer::PeekPacket(int & iBytesProceed, BYTE & header, DWORD & dwHandle, DWO
 	dwLength	= *((DWORD *) buf);
 	buf		+= sizeof(DWORD);
 
-	//sys_log(0, "%d header %d handle %u length %u", GetRecvLength(), header, dwHandle, dwLength);
+    // Ensure that all the data was fully received
 	if (iBytesProceed + dwLength + 9 > (DWORD) GetRecvLength())
 	{
 		sys_log(0, "PeekPacket: not enough buffer size: len %u, recv %d", 
@@ -85,6 +92,17 @@ bool CPeer::PeekPacket(int & iBytesProceed, BYTE & header, DWORD & dwHandle, DWO
 		return false;
 	}
 
+    // Ensure that all the required data is available in a contiguous area
+    buf = (const char *) GetRecvBuffer(iBytesProceed + dwLength + 9);
+    if (!buf) {
+        sys_err("PeekPacket: Failed to get network buffer!");
+        return false;
+    }
+
+    // Skip the header
+    buf += iBytesProceed + 9;
+
+    // Set the data pointer
 	*data = buf;
 	iBytesProceed += dwLength + 9;
 	return true;
diff --git a/game/CMakeLists.txt b/game/CMakeLists.txt
index 25d8b4f..c33277e 100644
--- a/game/CMakeLists.txt
+++ b/game/CMakeLists.txt
@@ -49,4 +49,3 @@ find_package (Threads REQUIRED)
 target_link_libraries (${PROJECT_NAME} Threads::Threads)
 
 target_link_libraries(${PROJECT_NAME} libgame libpoly libsql libthecore liblua)
-