Fix for Bug#32954396, EXECUTEQUERY HANGS WITH USECURSORFETCH=TRUE & SETFETCHSIZE.

Author: fjssilva

CHANGES

@@ -3,6 +3,8 @@
 
 Version 8.0.26
 
+  - Fix for Bug#32954396, EXECUTEQUERY HANGS WITH USECURSORFETCH=TRUE & SETFETCHSIZE.
+
   - Fix for Bug#102372 (32459408), v8.0.23 unusable in OSGi.
 
   - Fix for Bug#25554464, CONNECT FAILS WITH NPE WHEN THE SERVER STARTED WITH CUSTOM COLLATION.

src/main/protocol-impl/java/com/mysql/cj/protocol/a/BinaryResultsetReader.java

@@ -69,18 +69,20 @@ public Resultset read(int maxRows, boolean streamResults, NativePacketPayload re
             // Read in the column information
             ColumnDefinition cdef = this.protocol.read(ColumnDefinition.class, new MergingColumnDefinitionFactory(columnCount, metadata));
 
-            boolean isCursorPosible = this.protocol.getPropertySet().getBooleanProperty(PropertyKey.useCursorFetch).getValue()
+            boolean isCursorPossible = this.protocol.getPropertySet().getBooleanProperty(PropertyKey.useCursorFetch).getValue()
                     && resultSetFactory.getResultSetType() == Type.FORWARD_ONLY && resultSetFactory.getFetchSize() > 0;
 
             // There is no EOF packet after fields when CLIENT_DEPRECATE_EOF is set;
-            // if we asked to use cursor then there should be an OK packet here
-            if (isCursorPosible || !this.protocol.getServerSession().isEOFDeprecated()) {
-                this.protocol.readServerStatusForResultSets(this.protocol.readMessage(this.protocol.getReusablePacket()), true);
+            // if we asked to use cursor then there should be an OK or an ERR packet here
+            if (isCursorPossible || !this.protocol.getServerSession().isEOFDeprecated()) {
+                NativePacketPayload rowPacket = this.protocol.readMessage(this.protocol.getReusablePacket());
+                this.protocol.checkErrorMessage(rowPacket);
+                this.protocol.readServerStatusForResultSets(rowPacket, true);
             }
 
             ResultsetRows rows = null;
 
-            if (isCursorPosible && this.protocol.getServerSession().cursorExists()) {
+            if (isCursorPossible && this.protocol.getServerSession().cursorExists()) {
                 rows = new ResultsetRowsCursor(this.protocol, cdef);
 
             } else if (!streamResults) {

src/main/protocol-impl/java/com/mysql/cj/protocol/a/NativeProtocol.java

@@ -1661,7 +1661,7 @@ public final <T> T readServerStatusForResultSets(NativePacketPayload rowPacket,
         T result = null;
         if (rowPacket.isEOFPacket()) {
             // read EOF packet
-            rowPacket.readInteger(IntegerDataType.INT1); // skips the 'last packet' flag (packet signature)
+            rowPacket.setPosition(1); // skip the packet signature header
             this.warningCount = (int) rowPacket.readInteger(IntegerDataType.INT2);
             if (this.warningCount > 0) {
                 this.hadWarnings = true; // this is a 'latch', it's reset by sendCommand()

src/test/java/testsuite/regression/ResultSetRegressionTest.java

@@ -6979,6 +6979,7 @@ public Void call() throws Exception {
                 assertEquals('a', rs1.getBytes(2)[0]);
                 assertEquals('a', rs1.getByte(2));
                 assertThrows(SQLDataException.class, "Cannot determine value type from string 'a'", new Callable<Void>() {
+
                     public Void call() throws Exception {
                         rs1.getInt(2);
                         return null;
@@ -7074,6 +7075,7 @@ public Void call() throws Exception {
                 });
                 assertTrue(rs1.getString(5).startsWith("23"));
             }
+
         }
     }
 
@@ -7947,4 +7949,33 @@ public void testBug20802947() throws Exception {
         }
         rs1.close();
     }
+
+    /**
+     * Test fix for Bug#32954396, EXECUTEQUERY HANGS WITH USECURSORFETCH=TRUE & SETFETCHSIZE.
+     * 
+     * @throws Exception
+     */
+    @Test
+    public void testBug32954396() throws Exception {
+        createTable("testBug32954396", "(id INT, name VARCHAR(10))");
+
+        this.stmt.executeUpdate("INSERT INTO testBug32954396 VALUES (1, 'value1'), (2, 'value2')");
+
+        boolean useCursorFetch = false;
+        boolean setFetchSize = false;
+        do {
+            String testCase = String.format("Case: [useCursorFetch=%s, setFetchSize=%s]", useCursorFetch ? "Y" : "N", setFetchSize ? "Y" : "N");
+            Properties props = new Properties();
+            props.setProperty(PropertyKey.socketTimeout.getKeyName(), "1000");
+            props.setProperty(PropertyKey.useCursorFetch.getKeyName(), Boolean.toString(useCursorFetch));
+            Connection testConn = getConnectionWithProps(props);
+
+            this.pstmt = testConn.prepareStatement("SELECT id, name, (SELECT id FROM testBug32954396) FROM testBug32954396");
+            if (setFetchSize) {
+                this.pstmt.setFetchSize(1);
+            }
+            assertThrows(testCase, SQLException.class, "Subquery returns more than 1 row", this.pstmt::executeQuery);
+            testConn.close();
+        } while ((useCursorFetch = !useCursorFetch) || (setFetchSize = !setFetchSize));
+    }
 }