Fix crash on too-long theme definitions

Long file names for texture and pieces could make theme definitions
so long as to overflow the buffers used to hold them. The buffer
size is now doubled.

diff --git a/backend.c b/backend.c
index d7788cb..2e9e18d 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -11215,7 +11215,7 @@ CreateTourney (char *name)
 int
 NamesToList (char *names, char **engineList, char **engineMnemonic, char *group)
 {
-    char buf[MSG_SIZ], *p, *q;
+    char buf[2*MSG_SIZ], *p, *q;
     int i=1, header, skip, all = !strcmp(group, "all"), depth = 0;
     insert = names; // afterwards, this global will point just after last retrieved engine line or group end in the 'names'
     skip = !all && group[0]; // if group requested, we start in skip mode
@@ -19066,9 +19066,10 @@ int transparency[2];
 void
 LoadTheme ()
 {
-    char *p, *q, buf[MSG_SIZ];
+#define BUF_SIZ (2*MSG_SIZ)
+    char *p, *q, buf[BUF_SIZ];
     if(engineLine && engineLine[0]) { // a theme was selected from the listbox
-       snprintf(buf, MSG_SIZ, "-theme %s", engineLine);
+       snprintf(buf, BUF_SIZ, "-theme %s", engineLine);
        ParseArgsFromString(buf);
        ActivateTheme(TRUE); // also redo colors
        return;
@@ -19078,46 +19079,46 @@ LoadTheme ()
     {
        int len;
        q = appData.themeNames;
-       snprintf(buf, MSG_SIZ, "\"%s\"", nickName);
+       snprintf(buf, BUF_SIZ, "\"%s\"", nickName);
       if(appData.useBitmaps) {
-       snprintf(buf+strlen(buf), MSG_SIZ-strlen(buf), " -ubt true -lbtf \"%s\" -dbtf \"%s\" -lbtm %d -dbtm %d",
+       snprintf(buf+strlen(buf), BUF_SIZ-strlen(buf), " -ubt true -lbtf \"%s\" -dbtf \"%s\" -lbtm %d -dbtm %d",
                appData.liteBackTextureFile, appData.darkBackTextureFile,
                appData.liteBackTextureMode,
                appData.darkBackTextureMode );
       } else {
-       snprintf(buf+strlen(buf), MSG_SIZ-strlen(buf), " -ubt false");
+       snprintf(buf+strlen(buf), BUF_SIZ-strlen(buf), " -ubt false");
       }
       if(!appData.useBitmaps || transparency[0]) {
-       snprintf(buf+strlen(buf), MSG_SIZ-strlen(buf), " -lsc %s", Col2Text(2) ); // lightSquareColor
+       snprintf(buf+strlen(buf), BUF_SIZ-strlen(buf), " -lsc %s", Col2Text(2) ); // lightSquareColor
       }
       if(!appData.useBitmaps || transparency[1]) {
-       snprintf(buf+strlen(buf), MSG_SIZ-strlen(buf), " -dsc %s", Col2Text(3) ); // darkSquareColor
+       snprintf(buf+strlen(buf), BUF_SIZ-strlen(buf), " -dsc %s", Col2Text(3) ); // darkSquareColor
       }
       if(appData.useBorder) {
-       snprintf(buf+strlen(buf), MSG_SIZ-strlen(buf), " -ub true -border \"%s\"",
+       snprintf(buf+strlen(buf), BUF_SIZ-strlen(buf), " -ub true -border \"%s\"",
                appData.border);
       } else {
-       snprintf(buf+strlen(buf), MSG_SIZ-strlen(buf), " -ub false");
+       snprintf(buf+strlen(buf), BUF_SIZ-strlen(buf), " -ub false");
       }
       if(appData.useFont) {
-       snprintf(buf+strlen(buf), MSG_SIZ-strlen(buf), " -upf true -pf \"%s\" -fptc \"%s\" -fpfcw %s -fpbcb %s",
+       snprintf(buf+strlen(buf), BUF_SIZ-strlen(buf), " -upf true -pf \"%s\" -fptc \"%s\" -fpfcw %s -fpbcb %s",
                appData.renderPiecesWithFont,
                appData.fontToPieceTable,
                Col2Text(9),    // appData.fontBackColorWhite
                Col2Text(10) ); // appData.fontForeColorBlack
       } else {
-       snprintf(buf+strlen(buf), MSG_SIZ-strlen(buf), " -upf false");
+       snprintf(buf+strlen(buf), BUF_SIZ-strlen(buf), " -upf false");
        if(appData.pieceDirectory[0]) {
-         snprintf(buf+strlen(buf), MSG_SIZ-strlen(buf), " -pid \"%s\"", appData.pieceDirectory);
+         snprintf(buf+strlen(buf), BUF_SIZ-strlen(buf), " -pid \"%s\"", appData.pieceDirectory);
          if(appData.trueColors != 2) // 2 is a kludge to suppress this in WinBoard
-           snprintf(buf+strlen(buf), MSG_SIZ-strlen(buf), " -trueColors %s", appData.trueColors ? "true" : "false");
+           snprintf(buf+strlen(buf), BUF_SIZ-strlen(buf), " -trueColors %s", appData.trueColors ? "true" : "false");
        }
        if(!appData.pieceDirectory[0] || !appData.trueColors)
-         snprintf(buf+strlen(buf), MSG_SIZ-strlen(buf), " -wpc %s -bpc %s",
+         snprintf(buf+strlen(buf), BUF_SIZ-strlen(buf), " -wpc %s -bpc %s",
                Col2Text(0),   // whitePieceColor
                Col2Text(1) ); // blackPieceColor
       }
-      snprintf(buf+strlen(buf), MSG_SIZ-strlen(buf), " -hsc %s -phc %s\n",
+      snprintf(buf+strlen(buf), BUF_SIZ-strlen(buf), " -hsc %s -phc %s\n",
                Col2Text(4),   // highlightSquareColor
                Col2Text(5) ); // premoveHighlightColor
        appData.themeNames = malloc(len = strlen(q) + strlen(buf) + 1);