[core] Use ashmem_create_region (#1304)

core/src/main/cpp/main/api/zygisk_main.cpp

@@ -19,6 +19,7 @@
 
 #include <sys/socket.h>
 #include <fcntl.h>
+#include <dlfcn.h>
 
 #include "jni/zygisk.h"
 #include "logging.h"
@@ -181,9 +182,9 @@ namespace lspd {
                 return;
             }
 
-            if (int fd; read_int(companion) == 0 && (fd = recv_fd(companion)) != -1) {
+            if (int fd = -1, size = 0; (size = read_int(companion)) > 0 &&
-                Context::GetInstance()->PreLoadDex(
+                                       (fd = recv_fd(companion)) != -1) {
-                        "/proc/self/fd/" + std::to_string(fd));
+                Context::GetInstance()->PreLoadDex(fd, size);
                 close(fd);
             } else {
                 LOGE("Failed to read dex fd");
@@ -211,19 +212,49 @@ namespace lspd {
         }
     };
 
-    bool InitCompanion() {
+    std::tuple<int, std::size_t> InitCompanion() {
-        LOGD("onModuleLoaded: welcome to LSPosed!");
+        LOGI("onModuleLoaded: welcome to LSPosed!");
-        LOGD("onModuleLoaded: version v%s (%d)", versionName, versionCode);
+        LOGI("onModuleLoaded: version v%s (%d)", versionName, versionCode);
-        return true;
+
+        int (*ashmem_create_region)(const char *name, std::size_t size) = nullptr;
+        int (*ashmem_set_prot_region)(int fd, int prot) = nullptr;
+
+        std::string path = "/data/adb/modules/"s + lspd::moduleName + "/" + kDexPath;
+        int fd = open(path.data(), O_RDONLY | O_CLOEXEC);
+        if (fd < 0) {
+            LOGE("Failed to load dex: %s", path.data());
+            return {-1, 0};
+        }
+        auto fsize = lseek(fd, 0, SEEK_END);
+        lseek(fd, 0, SEEK_SET);
+        auto *cutils = dlopen("/system/lib" LP_SELECT("", "64") "/libcutils.so", 0);
+        ashmem_create_region = cutils ? reinterpret_cast<decltype(ashmem_create_region)>(
+                dlsym(cutils, "ashmem_create_region")) : nullptr;
+        ashmem_set_prot_region = cutils ? reinterpret_cast<decltype(ashmem_set_prot_region)>(
+                dlsym(cutils, "ashmem_set_prot_region")) : nullptr;
+        int tmp_fd = -1;
+        if (void *addr = nullptr;
+                ashmem_create_region && ashmem_set_prot_region &&
+                (tmp_fd = ashmem_create_region("lspd.dex", fsize)) > 0 &&
+                (addr = mmap(nullptr, fsize, PROT_WRITE, MAP_SHARED, tmp_fd, 0)) &&
+                read(fd, addr, fsize) > 0 && munmap(addr, fsize) == 0) {
+            LOGD("using memfd");
+            ashmem_set_prot_region(tmp_fd, PROT_READ);
+            std::swap(fd, tmp_fd);
+        } else {
+            LOGD("using raw fd");
+        }
+
+        close(tmp_fd);
+        dlclose(cutils);
+        return {fd, fsize};
     }
 
     void CompanionEntry(int client) {
         using namespace std::string_literals;
-        static bool inited = InitCompanion();
+        static auto[fd, size] = InitCompanion();
-        static std::string path = "/data/adb/modules/"s + lspd::moduleName + "/" + kDexPath;
+        if (fd > 0 && size > 0) {
-        static int fd = open(path.data(), O_RDONLY | O_CLOEXEC);
+            write_int(client, size);
-        if (inited && fd > 0) {
-            write_int(client, 0);
             send_fd(client, fd);
         } else write_int(client, -1);
         close(client);

core/src/main/cpp/main/src/context.cpp

@@ -58,11 +58,8 @@ namespace lspd {
         }
     }
 
-    Context::PreloadedDex::PreloadedDex(FILE *f) {
+    Context::PreloadedDex::PreloadedDex(int fd, std::size_t size) {
-        fseek(f, 0, SEEK_END);
+        if (auto addr = mmap(nullptr, size, PROT_READ, MAP_SHARED, fd, 0); addr) {
-        auto size = ftell(f);
-        rewind(f);
-        if (auto addr = mmap(nullptr, size, PROT_READ, MAP_SHARED, fileno(f), 0); addr) {
             addr_ = addr;
             size_ = size;
         } else {
@@ -74,17 +71,25 @@ namespace lspd {
         if (*this) munmap(addr_, size_);
     }
 
+    void Context::PreLoadDex(int fd, std::size_t size) {
+        dex_ = PreloadedDex{fd, size};
+    }
+
     void Context::PreLoadDex(std::string_view dex_path) {
         if (dex_) [[unlikely]] return;
 
         std::unique_ptr<FILE, decltype(&fclose)> f{fopen(dex_path.data(), "rb"), &fclose};
 
-        if (!f || !(dex_ = PreloadedDex(f.get()))) {
+        if (!f) {
             LOGE("Fail to open dex from %s", dex_path.data());
             return;
+        } else {
+            fseek(f.get(), 0, SEEK_END);
+            auto size = ftell(f.get());
+            rewind(f.get());
+            PreLoadDex(fileno(f.get()), size);
         }
-
+        LOGD("Loaded %s with size %zu", dex_path.data(), dex_.size());
-        LOGI("Loaded %s with size %zu", dex_path.data(), dex_.size());
     }
 
     void Context::LoadDex(JNIEnv *env) {
@@ -272,4 +277,4 @@ namespace lspd {
             *allowUnload = unload ? 1 : 0;
         }
     }
-}
+}  // namespace lspd

core/src/main/cpp/main/src/context.h

@@ -61,6 +61,8 @@ namespace lspd {
 
         void PreLoadDex(std::string_view dex_paths);
 
+        void PreLoadDex(int fd, std::size_t size);
+
         void Init();
 
     private:
@@ -80,6 +82,8 @@ namespace lspd {
 
             PreloadedDex &operator=(const PreloadedDex &) = delete;
 
+            PreloadedDex(int fd, std::size_t size);
+
             PreloadedDex &operator=(PreloadedDex &&other) {
                 addr_ = other.addr_;
                 size_ = other.size_;
@@ -99,8 +103,6 @@ namespace lspd {
 
             auto data() const { return addr_; }
 
-            PreloadedDex(FILE *f);
-
             ~PreloadedDex();
 
         private:

core/src/main/java/org/lsposed/lspd/service/ConfigManager.java

@@ -927,9 +927,8 @@ public class ConfigManager {
 
     public static List<String> getDenyListPackages() {
         List<String> result = new ArrayList<>();
-        try {
+        try (final SQLiteDatabase magiskDb =
-            final SQLiteDatabase magiskDb =
+                     SQLiteDatabase.openDatabase(ConfigFileManager.magiskDbPath, new SQLiteDatabase.OpenParams.Builder().addOpenFlags(SQLiteDatabase.OPEN_READONLY).build())) {
-                    SQLiteDatabase.openDatabase(ConfigFileManager.magiskDbPath, new SQLiteDatabase.OpenParams.Builder().addOpenFlags(SQLiteDatabase.OPEN_READONLY).build());
             try (Cursor cursor = magiskDb.query(true, "denylist", new String[]{"package_name"}, null, null, null, null, null, null, null)) {
                 if (cursor == null) return result;
                 int packageNameIdx = cursor.getColumnIndex("package_name");