我正在构建一个试图执行某些命令的应用程序,例如" top"和别的。 我正在研究android 7.0。 我在较旧的Android版本中尝试此代码,但当我在牛轧糖上尝试它时,我得到以下错误权限被拒绝:
E/AndroidRuntime: FATAL EXCEPTION: AsyncTask #1
Process: com.example.matant.cmdlineapp, PID: 7662
java.lang.RuntimeException: An error occurred while executing doInBackground()
at android.os.AsyncTask$3.done(AsyncTask.java:325)
at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:354)
at java.util.concurrent.FutureTask.setException(FutureTask.java:223)
at java.util.concurrent.FutureTask.run(FutureTask.java:242)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:243)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
at java.lang.Thread.run(Thread.java:761)
Caused by: java.lang.RuntimeException: java.io.IOException: Cannot run program "adb shell top": error=13, Permission denied
at com.example.matant.cmdlineapp.MainActivity$RunningTopCommand.doInBackground(MainActivity.java:88)
at com.example.matant.cmdlineapp.MainActivity$RunningTopCommand.doInBackground(MainActivity.java:36)
at android.os.AsyncTask$2.call(AsyncTask.java:305)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:243)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
at java.lang.Thread.run(Thread.java:761)
Caused by: java.io.IOException: Cannot run program "adb shell top": error=13, Permission denied
at java.lang.ProcessBuilder.start(ProcessBuilder.java:983)
at com.example.matant.cmdlineapp.MainActivity$RunningTopCommand.doInBackground(MainActivity.java:62)
at com.example.matant.cmdlineapp.MainActivity$RunningTopCommand.doInBackground(MainActivity.java:36)
at android.os.AsyncTask$2.call(AsyncTask.java:305)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:243)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
at java.lang.Thread.run(Thread.java:761)
Caused by: java.io.IOException: error=13, Permission denied
at java.lang.UNIXProcess.forkAndExec(Native Method)
at java.lang.UNIXProcess.<init>(UNIXProcess.java:133)
at java.lang.ProcessImpl.start(ProcessImpl.java:128)
at java.lang.ProcessBuilder.start(ProcessBuilder.java:964)
at com.example.matant.cmdlineapp.MainActivity$RunningTopCommand.doInBackground(MainActivity.java:62)
at com.example.matant.cmdlineapp.MainActivity$RunningTopCommand.doInBackground(MainActivity.java:36)
at android.os.AsyncTask$2.call(AsyncTask.java:305)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:243)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
at java.lang.Thread.run(Thread.java:761)
我正在执行的代码是:
protected Void doInBackground(String... params) {
//Execution en BackGround
Log.d("BACKGROUND", "START");
Log.d("BACK PARAM 0", params[0]);
//Log.d("BACK PARAM 1", params[1]);
try {
// Executes the command.
//Process process = Runtime.getRuntime().exec("adb version");
ProcessBuilder processBuilder = new ProcessBuilder("adb shell top");
Process process = processBuilder.start();
// Reads stdout.
// NOTE: You can write to stdin of the command using
// process.getOutputStream().
BufferedReader reader = new BufferedReader(
new InputStreamReader(process.getInputStream()));
int read;
char[] buffer = new char[4096];
StringBuffer output = new StringBuffer();
while ((read = reader.read(buffer)) > 0) {
output.append(buffer, 0, read);
Log.d("reader val: ",output.toString());
publishProgress(output.toString());
}
reader.close();
return null;
} catch (IOException e) {
throw new RuntimeException(e);
}
}
答案 0 :(得分:2)
来自this
众所周知,/ sys和/ proc泄漏了侧信道信息 关于过程,可用于推断状态的信息 过程。例如,多年来已经记录了/ proc 访问可用于监控应用程序启动,启用网络钓鱼 攻击。
因此,随着N的发布,开发团队故意限制/sys
和/proc
的访问权限。如果我没有弄错的话,adb top
命令也完全依赖于/proc
州的阅读。我认为这是因为不能在没有遇到从Android N开始的权限被拒绝错误的情况下通过top
执行ProcessBuilder
命令。