Fix a uretprobe issue (eunomia-bpf#31)

* Update a new simple example to test uretprobe

* Fix uretprobe attaching

* Remove simple_uretprobe_test

example/.gitignore

@@ -0,0 +1 @@
+simple_uretprobe_test*

runtime/include/hook_entry.hpp

@@ -35,7 +35,7 @@ struct hook_entry {
 
 	// listener for uprobe
 	GumInvocationListener *listener = nullptr;
-	int uretprobe_id;
+	int uretprobe_id = -1;
 	std::set<const bpftime_prog *> ret_progs;
 };
 // get hook entry from probe context

runtime/src/attach/attach_internal.cpp

@@ -89,8 +89,6 @@ void *__frida_bpftime_filter_handler()
 		    (void *)arg4);
 }
 
-
-
 typedef struct _UprobeListener UprobeListener;
 
 struct _UprobeListener {
@@ -115,9 +113,9 @@ static void uprobe_listener_on_enter(GumInvocationListener *listener,
 	if (hook_entry->progs.size() == 0) {
 		return;
 	}
+	spdlog::trace("Handle uprobe at uprobe_listener_on_enter");
 	GumInvocationContext *ctx;
 	pt_regs regs;
-
 	ctx = gum_interceptor_get_current_invocation();
 	convert_gum_cpu_context_to_pt_regs(*ctx->cpu_context, regs);
 	for (auto &prog : hook_entry->progs) {
@@ -138,7 +136,7 @@ static void uprobe_listener_on_leave(GumInvocationListener *listener,
 	if (hook_entry->ret_progs.size() == 0) {
 		return;
 	}
-
+	spdlog::trace("Handle uretprobe at uprobe_listener_on_leave");
 	pt_regs regs;
 	GumInvocationContext *ctx;
 	ctx = gum_interceptor_get_current_invocation();
@@ -181,6 +179,8 @@ static void frida_uprobe_listener_on_enter(_GumInvocationContext *ic,
 	GumInvocationContext *ctx;
 	pt_regs regs;
 
+	spdlog::trace("Handle uprobe at frida_uprobe_listener_on_enter");
+
 	ctx = gum_interceptor_get_current_invocation();
 	convert_gum_cpu_context_to_pt_regs(*ctx->cpu_context, regs);
 	for (auto &prog : hook_entry->progs) {
@@ -201,6 +201,7 @@ static void frida_uprobe_listener_on_leave(_GumInvocationContext *ic,
 		return;
 	}
 
+	spdlog::trace("Handle uretprobe at frida_uprobe_listener_on_leave");
 	pt_regs regs;
 	GumInvocationContext *ctx;
 	ctx = gum_interceptor_get_current_invocation();

runtime/src/attach/bpf_attach_ctx.cpp

@@ -277,6 +277,9 @@ int bpf_attach_ctx::init_attach_ctx_from_handlers(
 			}
 			case bpf_perf_event_handler::bpf_event_type::
 				BPF_TYPE_UPROBE: {
+				spdlog::debug(
+					"Creating uprobe for perf event fd {}",
+					i);
 				fd = create_uprobe(function, i, false);
 				break;
 			}
@@ -466,6 +469,9 @@ int bpf_attach_ctx::attach_prog(const bpftime_prog *prog, int id)
 		break;
 	}
 	case BPFTIME_UPROBE: {
+		spdlog::trace(
+			"Insert uprobe/uretprobe program for prog id {}, entry uretprobe id {}",
+			id, entry.uretprobe_id);
 		if (entry.uretprobe_id == id) {
 			entry.ret_progs.insert(prog);
 		} else {

runtime/src/bpftime_shm_internal.cpp

@@ -112,7 +112,7 @@ int bpftime_shm::add_uprobe(int pid, const char *name, uint64_t offset,
 	int fd = open_fake_fd();
 	manager->set_handler(
 		fd,
-		bpftime::bpf_perf_event_handler{ false, offset, pid, name,
+		bpftime::bpf_perf_event_handler{ retprobe, offset, pid, name,
 						 ref_ctr_off, segment },
 		segment);
 	return fd;

runtime/syscall-server/syscall_context.cpp

@@ -223,14 +223,15 @@ int syscall_context::handle_perfevent(perf_event_attr *attr, pid_t pid, int cpu,
 	try_startup();
 	if ((int)attr->type == determine_uprobe_perf_type()) {
 		// NO legacy bpf types
-		bool retprobe = attr->config & determine_uprobe_retprobe_bit();
+		bool retprobe =
+			attr->config & (1 << determine_uprobe_retprobe_bit());
 		size_t ref_ctr_off =
 			attr->config >> PERF_UPROBE_REF_CTR_OFFSET_SHIFT;
 		const char *name = (const char *)(uintptr_t)attr->config1;
 		uint64_t offset = attr->config2;
 		spdlog::debug(
-			"Creating uprobe name {} offset {} retprove {} ref_ctr_off {}",
-			name, offset, retprobe, ref_ctr_off);
+			"Creating uprobe name {} offset {} retprobe {} ref_ctr_off {} attr->config={:x}",
+			name, offset, retprobe, ref_ctr_off, attr->config);
 		int id = bpftime_uprobe_create(pid, name, offset, retprobe,
 					       ref_ctr_off);
 		// std::cout << "Created uprobe " << id << std::endl;