From b8ab0b5de0243b7a4a849148d584b2e6199e10b3 Mon Sep 17 00:00:00 2001
From: dan <Dan Kennedy>
Date: Mon, 2 Sep 2024 18:41:59 +0000
Subject: Fix a technically undefined signed integer overflow in fts5.

FossilOrigin-Name: e6bec37ea1ca51e1d048941ce4c5211d8fc5c5e3556a1441f9c79b036843f9e3
---
 ext/fts5/fts5_index.c             |  2 +-
 ext/fts5/test/fts5integrity2.test | 56 +++++++++++++++++++++++++++++++
 2 files changed, 57 insertions(+), 1 deletion(-)
 create mode 100644 ext/fts5/test/fts5integrity2.test

diff --git a/ext/fts5/fts5_index.c b/ext/fts5/fts5_index.c
index 7eca9b1321..86d90deb69 100644
--- a/ext/fts5/fts5_index.c
+++ b/ext/fts5/fts5_index.c
@@ -1977,7 +1977,7 @@ static void fts5SegIterNext_None(
 
   if( iOff<pIter->iEndofDoclist ){
     /* Next entry is on the current page */
-    i64 iDelta;
+    u64 iDelta;
     iOff += sqlite3Fts5GetVarint(&pIter->pLeaf->p[iOff], (u64*)&iDelta);
     pIter->iLeafOffset = iOff;
     pIter->iRowid += iDelta;
diff --git a/ext/fts5/test/fts5integrity2.test b/ext/fts5/test/fts5integrity2.test
new file mode 100644
index 0000000000..968be3bddf
--- /dev/null
+++ b/ext/fts5/test/fts5integrity2.test
@@ -0,0 +1,56 @@
+# 2024 September 3
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#***********************************************************************
+#
+# This file contains tests focused on the integrity-check procedure.
+#
+
+source [file join [file dirname [info script]] fts5_common.tcl]
+set testprefix fts5integrity2
+
+# If SQLITE_ENABLE_FTS5 is not defined, omit this file.
+ifcapable !fts5 {
+  finish_test
+  return
+}
+
+do_execsql_test 2.0 {
+  CREATE VIRTUAL TABLE t2 USING fts5(a, detail='none');
+  BEGIN;
+    INSERT INTO t2(rowid, a) VALUES(-1, 'hello world');
+    INSERT INTO t2(rowid, a) VALUES(9223372036854775807, 'hello world');
+  COMMIT;
+}
+
+do_execsql_test 2.1 {
+  SELECT rowid FROM t2('hello AND world');
+} {-1 9223372036854775807}
+
+#-------------------------------------------------------------------------
+do_execsql_test 2.0 {
+  CREATE VIRTUAL TABLE t1 USING fts5(a, detail='none');
+  CREATE TABLE r1(r);
+  
+  WITH c(x) AS (VALUES(1) UNION SELECT x<<1 FROM c)
+    INSERT INTO r1(r) SELECT -1-x FROM c;
+
+  INSERT INTO t1(rowid, a) SELECT r, 'abc' FROM r1;
+}
+
+do_execsql_test 2.1 {
+  PRAGMA integrity_check;
+} {ok}
+
+do_execsql_test 2.2 {
+  SELECT rowid FROM t1('abc') ORDER BY +rowid;
+} [db eval {SELECT r FROM r1 ORDER BY r}]
+
+
+finish_test
-- 
2.30.2