CSV: emit error when unbalanced double quotes are detected

Fixes OSGeo#11845

autotest/ogr/data/csv/unbalanced_double_quotes.csv

@@ -0,0 +1,3 @@
+id,txt
+1,"foo""
+2,bar

autotest/ogr/ogr_csv.py

@@ -3482,6 +3482,22 @@ def test_ogr_schema_override_wkt(tmp_vsimem):
         assert f.GetGeometryRef().ExportToWkt() == "POINT (1 2)"
 
 
+###############################################################################
+# Test reading CSV with unbalanced double-quotes
+
+
+@gdaltest.enable_exceptions()
+def test_ogr_csv_unbalanced_double_quotes():
+
+    with ogr.Open("data/csv/unbalanced_double_quotes.csv") as ds:
+        lyr = ds.GetLayer(0)
+        with pytest.raises(
+            Exception,
+            match="CSV file has unbalanced number of double-quotes. Corrupted data will likely be returned",
+        ):
+            lyr.GetNextFeature()
+
+
 ###############################################################################
 
 

port/cpl_csv.cpp

@@ -706,6 +706,14 @@ CSVReadParseLineGeneric(void *fp, const char *(*pfnReadLine)(void *, size_t),
     {
         CPLError(CE_Failure, CPLE_OutOfMemory, "%s", e.what());
     }
+
+    if (bInString)
+    {
+        CPLError(CE_Failure, CPLE_AppDefined,
+                 "CSV file has unbalanced number of double-quotes. Corrupted "
+                 "data will likely be returned");
+    }
+
     return nullptr;
 }