From 6f6395779765658e2a81d5b845583880efe53cb1 Mon Sep 17 00:00:00 2001
From: Matthias Kuhn <matthias@opengis.ch>
Date: Tue, 11 Dec 2018 15:49:07 +0100
Subject: [PATCH] Safety guard to prevent crashes

---
 src/providers/postgres/qgspostgresprovider.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/providers/postgres/qgspostgresprovider.cpp b/src/providers/postgres/qgspostgresprovider.cpp
index 247d53aee16d..fa0dc3fa9338 100644
--- a/src/providers/postgres/qgspostgresprovider.cpp
+++ b/src/providers/postgres/qgspostgresprovider.cpp
@@ -2700,7 +2700,9 @@ bool QgsPostgresProvider::changeAttributeValues( const QgsChangedAttributesMap &
       {
         QVariantList k = mShared->removeFid( fid );
 
-        for ( int i = 0; i < mPrimaryKeyAttrs.size(); i++ )
+        int keyCount = std::min( mPrimaryKeyAttrs.size(), k.size() );
+
+        for ( int i = 0; i < keyCount; i++ )
         {
           int idx = mPrimaryKeyAttrs.at( i );
           if ( !attrs.contains( idx ) )