Add new fuzz target for async responses

build.c

@@ -9,7 +9,7 @@ int main(int argc, char **argv) {
     char *CXX = strcpy(calloc(1024, 1), or_else(getenv("CXX"), "g++"));
     char *EXEC_SUFFIX = strcpy(calloc(1024, 1), maybe(getenv("EXEC_SUFFIX")));
 
-    char *EXAMPLE_FILES[] = {"Client", "Http3Server", "Broadcast", "HelloWorld", "Crc32", "ServerName",
+    char *EXAMPLE_FILES[] = {"Http3Server", "Broadcast", "HelloWorld", "Crc32", "ServerName",
     "EchoServer", "BroadcastingEchoServer", "UpgradeSync", "UpgradeAsync"};
 
     strcat(CXXFLAGS, " -O3 -Wpedantic -Wall -Wextra -Wsign-conversion -Wconversion -std=c++20 -Isrc -IuSockets/src");

fuzzing/AsyncEpollHelloWorld.cpp

@@ -0,0 +1,60 @@
+/* We rely on wrapped syscalls */
+#include "libEpollFuzzer/epoll_fuzzer.h"
+
+#include "App.h"
+
+/* We keep this one for teardown later on */
+struct us_listen_socket_t *listen_socket;
+
+/* This test is run by libEpollFuzzer */
+void test() {
+
+    {
+        /* Keep in mind that uWS::SSLApp({options}) is the same as uWS::App() when compiled without SSL support.
+        * You may swap to using uWS:App() if you don't need SSL */
+        auto app = uWS::App({
+            /* There are example certificates in uWebSockets.js repo */
+            .key_file_name = "../misc/key.pem",
+            .cert_file_name = "../misc/cert.pem",
+            .passphrase = "1234"
+        }).get("/*", [](auto *res, auto *req) {
+            bool *aborted = new bool;
+            *aborted = false;
+            res->onAborted([aborted]() {
+                *aborted = true;
+            });
+
+            uWS::Loop::get()->defer([res, aborted]() {
+                if (!*aborted) {
+                    res->cork([res, aborted]() {
+                        // Todo: also test upgrade to websocket here
+                        res->end("Hello async!");
+                    });
+                }
+                delete aborted;
+            });
+        }).listen(9001, [](auto *listenSocket) {
+            listen_socket = listenSocket;
+        });
+
+        app.run();
+    }
+    uWS::Loop::get()->free();
+}
+
+/* Thus function should shutdown the event-loop and let the test fall through */
+void teardown() {
+	/* If we are called twice there's a bug (it potentially could if
+	 * all open sockets cannot be error-closed in one epoll_wait call).
+	 * But we only allow 1k FDs and we have a buffer of 1024 from epoll_wait */
+	if (!listen_socket) {
+		exit(-1);
+	}
+
+	/* We might have open sockets still, and these will be error-closed by epoll_wait */
+	// us_socket_context_close - close all open sockets created with this socket context
+    if (listen_socket) {
+        us_listen_socket_close(0, listen_socket);
+        listen_socket = NULL;
+    }
+}

fuzzing/AsyncEpollHelloWorld.dict

@@ -0,0 +1,12 @@
+"get"
+"post"
+"get /"
+"http/1.1"
+"upgrade: websocket"
+"\x0D\x0A"
+"sec-websocket-key: dGhlIHNhbXBsZSBub25jZQ=="
+"sec-websocket-version: 13"
+"get / http/1.1"
+"sec-websocket-extensions: permessage-deflate"
+"sec-websocket-protocol: "
+" "

fuzzing/Makefile

@@ -18,6 +18,8 @@ oss-fuzz:
 	# Link against object files
 	$(CXX) $(CXXFLAGS) $(WRAPPED_SYSCALLS) -std=c++17 -O3 -DUWS_MOCK_ZLIB -I../src -I../uSockets/src EpollHelloWorld.cpp -o $(OUT)/EpollHelloWorld $(LIB_FUZZING_ENGINE) *.o
 	rm -f EpollHelloWorld.o
+	$(CXX) $(CXXFLAGS) $(WRAPPED_SYSCALLS) -std=c++17 -O3 -DUWS_MOCK_ZLIB -I../src -I../uSockets/src AsyncEpollHelloWorld.cpp -o $(OUT)/AsyncEpollHelloWorld $(LIB_FUZZING_ENGINE) *.o
+	rm -f AsyncEpollHelloWorld.o
 	$(CXX) $(CXXFLAGS) $(WRAPPED_SYSCALLS) -std=c++17 -O3 -DUWS_MOCK_ZLIB -I../src -I../uSockets/src EpollEchoServer.cpp -o $(OUT)/EpollEchoServer $(LIB_FUZZING_ENGINE) *.o
 	rm -f EpollEchoServer.o
 	$(CXX) $(CXXFLAGS) $(WRAPPED_SYSCALLS) -std=c++17 -O3 -DUWS_MOCK_ZLIB -I../src -I../uSockets/src EpollEchoServerPubSub.cpp -o $(OUT)/EpollEchoServerPubSub $(LIB_FUZZING_ENGINE) *.o