Merge #5130

5130: Fix memory leaks in auto stat CSV output, fix stringop-overflow warnings r=def- a=Robyt3

The memory allocated in and returned by `ReplaceCommata` was never freed.

Likewise `m_pCSVstr` allocated in `FormatStats` was never freed.

This also fixes a stringop-overflow warning and that the allocated memory size was missing one byte for the zero terminator.

The `ReplaceCommata` method is now also used for the gametype and map. Although unlikely, commata can be used in gametype and map names, so this prevents invalid CSVs for those cases.

Refactoring: remove unnecessary copy of `pStr` into `aBuf`.

## Checklist

- [X] Tested the change ingame
- [ ] Provided screenshots if it is a visual change
- [ ] Tested in combination with possibly related configuration options
- [ ] Written a unit test if it works standalone, system.c especially
- [ ] Considered possible null pointers and out of bounds array indexing
- [ ] Changed no physics that affect existing maps
- [ ] Tested the change with [ASan+UBSan or valgrind's memcheck](https://github.com/ddnet/ddnet/#using-addresssanitizer--undefinedbehavioursanitizer-or-valgrinds-memcheck) (optional)


Co-authored-by: Robert Müller <robytemueller@gmail.com>

src/engine/client/client.cpp

@@ -948,7 +948,7 @@ void CClient::GetServerInfo(CServerInfo *pServerInfo) const
 	mem_copy(pServerInfo, &m_CurrentServerInfo, sizeof(m_CurrentServerInfo));
 
 	if(m_DemoPlayer.IsPlaying() && g_Config.m_ClDemoAssumeRace)
-		str_copy(pServerInfo->m_aGameType, "DDraceNetwork", 14);
+		str_copy(pServerInfo->m_aGameType, "DDraceNetwork", sizeof(pServerInfo->m_aGameType));
 }
 
 void CClient::ServerInfoRequest()

src/game/client/components/statboard.cpp

@@ -14,7 +14,6 @@ CStatboard::CStatboard()
 	m_Active = false;
 	m_ScreenshotTaken = false;
 	m_ScreenshotTime = -1;
-	m_pCSVstr = 0;
 }
 
 void CStatboard::OnReset()
@@ -404,11 +403,11 @@ void CStatboard::AutoStatCSV()
 		str_format(aFilename, sizeof(aFilename), "screenshots/auto/stats_%s.csv", aDate);
 		IOHANDLE File = Storage()->OpenFile(aFilename, IOFLAG_WRITE, IStorage::TYPE_ALL);
 
-		FormatStats();
-
 		if(File)
 		{
-			io_write(File, m_pCSVstr, str_length(m_pCSVstr));
+			char aStats[1024 * (VANILLA_MAX_CLIENTS + 1)];
+			FormatStats(aStats, sizeof(aStats));
+			io_write(File, aStats, str_length(aStats));
 			io_close(File);
 		}
 
@@ -416,42 +415,36 @@ void CStatboard::AutoStatCSV()
 	}
 }
 
-char *CStatboard::ReplaceCommata(char *pStr)
+std::string CStatboard::ReplaceCommata(char *pStr)
 {
 	if(!str_find(pStr, ","))
 		return pStr;
 
-	char aBuf[64];
-	str_format(aBuf, sizeof(aBuf), "%s", pStr);
-
 	char aOutbuf[256];
 	mem_zero(aOutbuf, sizeof(aOutbuf));
 
 	for(int i = 0, skip = 0; i < 64; i++)
 	{
-		if(aBuf[i] == ',')
+		if(pStr[i] == ',')
 		{
 			aOutbuf[i + skip++] = '%';
 			aOutbuf[i + skip++] = '2';
 			aOutbuf[i + skip] = 'C';
 		}
 		else
-			aOutbuf[i + skip] = aBuf[i];
+			aOutbuf[i + skip] = pStr[i];
 	}
 
-	unsigned int len = str_length(aOutbuf);
-	char *buf = new char[len];
-	mem_copy(buf, aOutbuf, len);
-	return buf;
+	return aOutbuf;
 }
 
-void CStatboard::FormatStats()
+void CStatboard::FormatStats(char *pDest, size_t DestSize)
 {
 	// server stats
 	CServerInfo CurrentServerInfo;
 	Client()->GetServerInfo(&CurrentServerInfo);
 	char aServerStats[1024];
-	str_format(aServerStats, sizeof(aServerStats), "Servername,Game-type,Map\n%s,%s,%s", ReplaceCommata(CurrentServerInfo.m_aName), CurrentServerInfo.m_aGameType, CurrentServerInfo.m_aMap);
+	str_format(aServerStats, sizeof(aServerStats), "Servername,Game-type,Map\n%s,%s,%s", ReplaceCommata(CurrentServerInfo.m_aName).c_str(), ReplaceCommata(CurrentServerInfo.m_aGameType).c_str(), ReplaceCommata(CurrentServerInfo.m_aMap).c_str());
 
 	// player stats
 
@@ -514,8 +507,8 @@ void CStatboard::FormatStats()
 		str_format(aBuf, sizeof(aBuf), "%d,%d,%s,%s,%d,%d,%d,%d,%.2f,%i,%.1f,%d,%d,%s,%d,%d,%d\n",
 			localPlayer ? 1 : 0, // Local player
 			m_pClient->m_aClients[pInfo->m_ClientID].m_Team, // Team
-			ReplaceCommata(m_pClient->m_aClients[pInfo->m_ClientID].m_aName), // Name
-			ReplaceCommata(m_pClient->m_aClients[pInfo->m_ClientID].m_aClan), // Clan
+			ReplaceCommata(m_pClient->m_aClients[pInfo->m_ClientID].m_aName).c_str(), // Name
+			ReplaceCommata(m_pClient->m_aClients[pInfo->m_ClientID].m_aClan).c_str(), // Clan
 			clamp(pInfo->m_Score, -999, 999), // Score
 			pStats->m_Frags, // Frags
 			pStats->m_Deaths, // Deaths
@@ -533,10 +526,5 @@ void CStatboard::FormatStats()
 		str_append(aPlayerStats, aBuf, sizeof(aPlayerStats));
 	}
 
-	char aStats[1024 * (VANILLA_MAX_CLIENTS + 1)];
-	str_format(aStats, sizeof(aStats), "%s\n\n%s", aServerStats, aPlayerStats);
-
-	unsigned int Len = str_length(aStats);
-	m_pCSVstr = (char *)malloc(Len);
-	str_copy(m_pCSVstr, aStats, Len);
+	str_format(pDest, DestSize, "%s\n\n%s", aServerStats, aPlayerStats);
 }

src/game/client/components/statboard.h

@@ -2,6 +2,7 @@
 #define GAME_CLIENT_COMPONENTS_STATBOARD_H
 
 #include <game/client/component.h>
+#include <string>
 
 class CStatboard : public CComponent
 {
@@ -14,9 +15,8 @@ private:
 	void AutoStatScreenshot();
 	void AutoStatCSV();
 
-	char *m_pCSVstr;
-	char *ReplaceCommata(char *pStr);
-	void FormatStats();
+	std::string ReplaceCommata(char *pStr);
+	void FormatStats(char *pDest, size_t DestSize);
 
 public:
 	CStatboard();