Resolve /proc/self/exe before executing

topjohnwu · Jun 2, 2022 · 8ef7539 · 8ef7539
1 parent cae7a27
commit 8ef7539
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Showing 3 changed files with 35 additions and 32 deletions.
diff --git a/build.gradle.kts b/build.gradle.kts
@@ -15,7 +15,7 @@ buildscript {
     }
 
     dependencies {
-        classpath("com.android.tools.build:gradle:7.2.0")
+        classpath("com.android.tools.build:gradle:7.2.1")
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files

diff --git a/service/src/main/assets/main.jar b/service/src/main/assets/main.jar
diff --git a/service/src/main/java/com/topjohnwu/superuser/internal/RootServiceManager.java b/service/src/main/java/com/topjohnwu/superuser/internal/RootServiceManager.java
@@ -161,43 +161,46 @@ private Shell.Task startRootProcess(ComponentName name, String action) {
             context.registerReceiver(new ServiceReceiver(), filter);
         }
 
-        Context de = Utils.getDeContext(context);
-        File mainJar = new File(de.getCacheDir(), "main.jar");
+        return (stdin, stdout, stderr) -> {
+            Context ctx = Utils.getContext();
+            Context de = Utils.getDeContext(ctx);
+            File mainJar = new File(de.getCacheDir(), "main.jar");
 
-        String env = "";
-        String params = "";
+            // Dump main.jar as trampoline
+            try (InputStream in = ctx.getResources().getAssets().open("main.jar");
+                 OutputStream out = new FileOutputStream(mainJar)) {
+                Utils.pump(in, out);
+            }
 
-        if (Utils.vLog()) {
-            env = LOGGING_ENV + "=1 ";
-        }
+            String env = "";
+            String params = "";
 
-        // Only support debugging on SDK >= 27
-        if (Build.VERSION.SDK_INT >= 27 && Debug.isDebuggerConnected()) {
-            env += DEBUG_ENV + "=1 ";
-            // Reference of the params to start jdwp:
-            // https://developer.android.com/ndk/guides/wrap-script#debugging_when_using_wrapsh
-            if (Build.VERSION.SDK_INT == 27) {
-                params = API_27_DEBUG;
-            } else {
-                params = API_28_DEBUG;
+            if (Utils.vLog()) {
+                env = LOGGING_ENV + "=1 ";
             }
-        }
-
-        String cmd = String.format(Locale.ROOT,
-                "(%s CLASSPATH=%s /proc/%d/exe %s /system/bin --nice-name=%s:root " +
-                "com.topjohnwu.superuser.internal.RootServerMain %s %d %s %s >/dev/null 2>&1)&",
-                env, mainJar, Process.myPid(), params, context.getPackageName(),
-                name.flattenToString().replace("$", "\\$"), // args[0]
-                Process.myUid(),                            // args[1]
-                filterAction,                               // args[2]
-                action);                                    // args[3]
 
-        return (stdin, stdout, stderr) -> {
-            // Dump main.jar as trampoline
-            try (InputStream in = context.getResources().getAssets().open("main.jar");
-                 OutputStream out = new FileOutputStream(mainJar)) {
-                Utils.pump(in, out);
+            // Only support debugging on SDK >= 27
+            if (Build.VERSION.SDK_INT >= 27 && Debug.isDebuggerConnected()) {
+                env += DEBUG_ENV + "=1 ";
+                // Reference of the params to start jdwp:
+                // https://developer.android.com/ndk/guides/wrap-script#debugging_when_using_wrapsh
+                if (Build.VERSION.SDK_INT == 27) {
+                    params = API_27_DEBUG;
+                } else {
+                    params = API_28_DEBUG;
+                }
             }
+
+            String app_process = new File("/proc/self/exe").getCanonicalPath();
+            String cmd = String.format(Locale.ROOT,
+                    "(%s CLASSPATH=%s %s %s /system/bin --nice-name=%s:root " +
+                    "com.topjohnwu.superuser.internal.RootServerMain %s %d %s %s >/dev/null 2>&1)&",
+                    env, mainJar, app_process, params, ctx.getPackageName(),
+                    name.flattenToString().replace("$", "\\$"), // args[0]
+                    Process.myUid(),                            // args[1]
+                    filterAction,                               // args[2]
+                    action);                                    // args[3]
+
             Utils.log(TAG, cmd);
             // Write command to stdin
             byte[] bytes = cmd.getBytes(StandardCharsets.UTF_8);