Prevent any leaks when HttpPostStandardRequestDecoder constructor throws (#9837)

Motivation:

HttpPostStandardRequestDecoder may throw multiple different exceptions in the constructor which could lead to memory leaks. We need to guard against this by explicit catch all of them and rethrow after we released any allocated memory.

Modifications:

- Catch, destroy and rethrow in any case
- Ensure we correctly wrap IllegalArgumentExceptions
- Add unit tests

Result:

Fixes https://github.com/netty/netty/issues/9829

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

@@ -26,6 +26,7 @@ import io.netty.handler.codec.http.multipart.HttpPostRequestDecoder.EndOfDataDec
 import io.netty.handler.codec.http.multipart.HttpPostRequestDecoder.ErrorDataDecoderException;
 import io.netty.handler.codec.http.multipart.HttpPostRequestDecoder.MultiPartStatus;
 import io.netty.handler.codec.http.multipart.HttpPostRequestDecoder.NotEnoughDataDecoderException;
+import io.netty.util.internal.PlatformDependent;
 
 import java.io.IOException;
 import java.nio.charset.Charset;
@@ -157,9 +158,9 @@ public class HttpPostStandardRequestDecoder implements InterfaceHttpPostRequestD
                 undecodedChunk = buffer();
                 parseBody();
             }
-        } catch (HttpPostRequestDecoder.ErrorDataDecoderException e) {
+        } catch (Throwable e) {
             destroy();
-            throw e;
+            PlatformDependent.throwException(e);
         }
     }
 
@@ -486,6 +487,10 @@ public class HttpPostStandardRequestDecoder implements InterfaceHttpPostRequestD
             // error while decoding
             undecodedChunk.readerIndex(firstpos);
             throw new ErrorDataDecoderException(e);
+        } catch (IllegalArgumentException e) {
+            // error while decoding
+            undecodedChunk.readerIndex(firstpos);
+            throw new ErrorDataDecoderException(e);
         }
     }
 

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

@@ -736,6 +736,26 @@ public class HttpPostRequestDecoderTest {
         }
     }
 
+    @Test(expected = HttpPostRequestDecoder.ErrorDataDecoderException.class)
+    public void testNotLeakDirectBufferWhenWrapIllegalArgumentException() {
+        testNotLeakWhenWrapIllegalArgumentException(Unpooled.directBuffer());
+    }
+
+    @Test(expected = HttpPostRequestDecoder.ErrorDataDecoderException.class)
+    public void testNotLeakHeapBufferWhenWrapIllegalArgumentException() {
+        testNotLeakWhenWrapIllegalArgumentException(Unpooled.buffer());
+    }
+
+    private static void testNotLeakWhenWrapIllegalArgumentException(ByteBuf buf) {
+        buf.writeCharSequence("==", CharsetUtil.US_ASCII);
+        FullHttpRequest request = new DefaultFullHttpRequest(HttpVersion.HTTP_1_1, HttpMethod.POST, "/", buf);
+        try {
+            new HttpPostStandardRequestDecoder(request);
+        } finally {
+            assertTrue(request.release());
+        }
+    }
+
     @Test
     public void testMultipartFormDataContentType() {
         HttpRequest request = new DefaultHttpRequest(HttpVersion.HTTP_1_1, HttpMethod.POST, "/");