HttpPostStandardRequestDecoder leaks memory when constructor throws ErrorDataDecoderException. (#9517)

Motivation:

Currently when HttpPostStandardRequestDecoder throws a ErrorDataDecoderException during construction we leak memory. We need to ensure all is released correctly.

Modifications:

- Call destroy() if parseBody() throws and rethrow the ErrorDataDecoderException
- Add unit test

Result:

Fixes https://github.com/netty/netty/issues/9513.

codec-http/src/main/java/io/netty/handler/codec/http/multipart/HttpPostStandardRequestDecoder.java

@@ -148,13 +148,18 @@ public class HttpPostStandardRequestDecoder implements InterfaceHttpPostRequestD
         this.request = checkNotNull(request, "request");
         this.charset = checkNotNull(charset, "charset");
         this.factory = checkNotNull(factory, "factory");
-        if (request instanceof HttpContent) {
-            // Offer automatically if the given request is als type of HttpContent
-            // See #1089
-            offer((HttpContent) request);
-        } else {
-            undecodedChunk = buffer();
-            parseBody();
+        try {
+            if (request instanceof HttpContent) {
+                // Offer automatically if the given request is als type of HttpContent
+                // See #1089
+                offer((HttpContent) request);
+            } else {
+                undecodedChunk = buffer();
+                parseBody();
+            }
+        } catch (HttpPostRequestDecoder.ErrorDataDecoderException e) {
+            destroy();
+            throw e;
         }
     }
 

codec-http/src/test/java/io/netty/handler/codec/http/multipart/HttpPostRequestDecoderTest.java

@@ -723,4 +723,15 @@ public class HttpPostRequestDecoderTest {
         decoder.destroy();
         assertEquals(1, req.refCnt());
     }
+
+    @Test(expected = HttpPostRequestDecoder.ErrorDataDecoderException.class)
+    public void testNotLeak() {
+        FullHttpRequest request = new DefaultFullHttpRequest(HttpVersion.HTTP_1_1, HttpMethod.POST, "/",
+                Unpooled.copiedBuffer("a=1&&b=2", CharsetUtil.US_ASCII));
+        try {
+            new HttpPostStandardRequestDecoder(request);
+        } finally {
+            assertTrue(request.release());
+        }
+    }
 }