diff --git ext/fts3/fts3.c ext/fts3/fts3.c
index 20da051..71e22ae 100644
--- ext/fts3/fts3.c
+++ ext/fts3/fts3.c
@@ -291,6 +291,7 @@
 ** deletions and duplications.  This would basically be a forced merge
 ** into a single segment.
 */
+#define CHROMIUM_FTS3_CHANGES 1
 
 #if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
 
@@ -1226,7 +1227,13 @@ static int fts3ScanInteriorNode(
     isFirstTerm = 0;
     zCsr += sqlite3Fts3GetVarint32(zCsr, &nSuffix);
     
-    if( nPrefix<0 || nSuffix<0 || &zCsr[nSuffix]>zEnd ){
+    /* NOTE(shess): Previous code checked for negative nPrefix and
+    ** nSuffix and suffix overrunning zEnd.  Additionally corrupt if
+    ** the prefix is longer than the previous term, or if the suffix
+    ** causes overflow.
+    */
+    if( nPrefix<0 || nSuffix<0 || nPrefix>nBuffer
+     || &zCsr[nSuffix]<zCsr || &zCsr[nSuffix]>zEnd ){
       rc = SQLITE_CORRUPT;
       goto finish_scan;
     }
@@ -3646,7 +3660,11 @@ int sqlite3Fts3Init(sqlite3 *db){
   ** module with sqlite.
   */
   if( SQLITE_OK==rc 
+#if CHROMIUM_FTS3_CHANGES && !SQLITE_TEST
+      /* fts3_tokenizer() disabled for security reasons. */
+#else
    && SQLITE_OK==(rc = sqlite3Fts3InitHashTable(db, pHash, "fts3_tokenizer"))
+#endif
    && SQLITE_OK==(rc = sqlite3_overload_function(db, "snippet", -1))
    && SQLITE_OK==(rc = sqlite3_overload_function(db, "offsets", 1))
    && SQLITE_OK==(rc = sqlite3_overload_function(db, "matchinfo", 1))
@@ -3656,11 +3674,15 @@ int sqlite3Fts3Init(sqlite3 *db){
     rc = sqlite3_create_module_v2(
         db, "fts3", &fts3Module, (void *)pHash, hashDestroy
     );
+#if CHROMIUM_FTS3_CHANGES && !SQLITE_TEST
+    /* Disable fts4 pending review. */
+#else
     if( rc==SQLITE_OK ){
       rc = sqlite3_create_module_v2(
           db, "fts4", &fts3Module, (void *)pHash, 0
       );
     }
+#endif
     return rc;
   }
 
diff --git ext/fts3/fts3_icu.c ext/fts3/fts3_icu.c
index 85390d3..a75b14a 100644
--- ext/fts3/fts3_icu.c
+++ ext/fts3/fts3_icu.c
@@ -198,7 +198,7 @@ static int icuNext(
 
     while( iStart<iEnd ){
       int iWhite = iStart;
-      U8_NEXT(pCsr->aChar, iWhite, pCsr->nChar, c);
+      U16_NEXT(pCsr->aChar, iWhite, pCsr->nChar, c);
       if( u_isspace(c) ){
         iStart = iWhite;
       }else{