From f388a0c44d2abdbd582686e511fef36c1b96ae43 Mon Sep 17 00:00:00 2001
From: dan <Dan Kennedy>
Date: Thu, 7 Sep 2023 13:53:09 +0000
Subject: [PATCH] Fix a buffer overread in the sessions extension that could
 occur when processing a corrupt changeset.

Upstream-Status: Backport [https://sqlite.org/src/info/0e4e7a05c4204b47]
CVE: CVE-2023-7104

Signed-off-by: Peter Marko <peter.marko@siemens.com>
Signed-off-by: Vrushti Dabhi <vrushti.dabhi@einfochips.com>
---
 sqlite3.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/sqlite3.c b/sqlite3.c
index a16db27..0b979f7 100644
--- a/sqlite3.c
+++ b/sqlite3.c
@@ -213482,15 +213482,19 @@ static int sessionReadRecord(
         }
       }
       if( eType==SQLITE_INTEGER || eType==SQLITE_FLOAT ){
-        sqlite3_int64 v = sessionGetI64(aVal);
-        if( eType==SQLITE_INTEGER ){
-          sqlite3VdbeMemSetInt64(apOut[i], v);
+        if( (pIn->nData-pIn->iNext)<8 ){
+          rc = SQLITE_CORRUPT_BKPT;
         }else{
-          double d;
-          memcpy(&d, &v, 8);
-          sqlite3VdbeMemSetDouble(apOut[i], d);
+          sqlite3_int64 v = sessionGetI64(aVal);
+          if( eType==SQLITE_INTEGER ){
+            sqlite3VdbeMemSetInt64(apOut[i], v);
+          }else{
+            double d;
+            memcpy(&d, &v, 8);
+            sqlite3VdbeMemSetDouble(apOut[i], d);
+          }
+          pIn->iNext += 8;
         }
-        pIn->iNext += 8;
       }
     }
   }
