Add a test to ensure an application does not try to create a geopoly

virtual table with too many columns.
[bugs:/info/2026-05-30T12:47:27Z|Bug 2026-05-30T12:47:27Z].

FossilOrigin-Name: 2c605bfb1562d7a3609ad6ffd7446def12f1ac7084e41b9c6723e998c156501d

ext/rtree/geopoly.c

@@ -1251,6 +1251,11 @@ static int geopolyInit(
   int ii;
   (void)pAux;
 
+  if( argc>=RTREE_MAX_AUX_COLUMN+4 ){
+    *pzErr = sqlite3_mprintf("Too many columns for a geopoly table");
+    return SQLITE_ERROR;
+  }
+
   sqlite3_vtab_config(db, SQLITE_VTAB_CONSTRAINT_SUPPORT, 1);
   sqlite3_vtab_config(db, SQLITE_VTAB_INNOCUOUS);
 

ext/rtree/rtree.c

@@ -166,7 +166,7 @@ struct Rtree {
   u8 eCoordType;              /* RTREE_COORD_REAL32 or RTREE_COORD_INT32 */
   u8 nBytesPerCell;           /* Bytes consumed per cell */
   u8 inWrTrans;               /* True if inside write transaction */
-  u8 nAux;                    /* # of auxiliary columns in %_rowid */
+  u16 nAux;                   /* # of auxiliary columns in %_rowid */
 #ifdef SQLITE_ENABLE_GEOPOLY
   u8 nAuxNotNull;             /* Number of initial not-null aux columns */
 #endif
@@ -3644,7 +3644,7 @@ static int rtreeInit(
     "Auxiliary rtree columns must be last"                /* 4 */
   };
 
-  assert( RTREE_MAX_AUX_COLUMN<256 ); /* Aux columns counted by a u8 */
+  assert( RTREE_MAX_AUX_COLUMN<256 );
   if( argc<6 || argc>RTREE_MAX_AUX_COLUMN+3 ){
     *pzErr = sqlite3_mprintf("%s", aErrMsg[2 + (argc>=6)]);
     return SQLITE_ERROR;