/data/local/tmp/test error=13, Permission denied

Question

I have native executable on device at /data/local/tmp and using java api to run the exe java.runtime.exec() method. However, I get permission denied error:13(stacktrace attached below.)

String runexec= "/data/local/tmp/test";
Process p = Runtime.getRuntime().exec(runexec);




Java.io.IOException: Cannot run program "/data/local/tmp/test": error=13, Permission denied
W/System.err:     at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)
W/System.err:     at java.lang.Runtime.exec(Runtime.java:692)
W/System.err:     at java.lang.Runtime.exec(Runtime.java:525)
W/System.err:     at java.lang.Runtime.exec(Runtime.java:422)
W/System.err:     at android.view.View.performClick(View.java:6891)
W/System.err:     at android.widget.TextView.performClick(TextView.java:12651)
W/System.err:     at android.view.View$PerformClick.run(View.java:26083)
W/System.err:     at android.os.Handler.handleCallback(Handler.java:789)
W/System.err:     at android.os.Handler.dispatchMessage(Handler.java:98)
W/System.err:     at android.os.Looper.loop(Looper.java:164)
W/System.err:     at android.app.ActivityThread.main(ActivityThread.java:6938)
W/System.err:     at java.lang.reflect.Method.invoke(Native Method)
W/System.err:     at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
W/System.err:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)
W/System.err: Caused by: java.io.IOException: error=13, Permission denied
W/System.err:     at java.lang.UNIXProcess.forkAndExec(Native Method)
W/System.err:     at java.lang.UNIXProcess.<init>(UNIXProcess.java:133)
W/System.err:     at java.lang.ProcessImpl.start(ProcessImpl.java:128)
W/System.err:     at java.lang.ProcessBuilder.start(Pro

Edit: test exe has a+x or say 777 permission and functions properly via adb shell however, fails when invoked with java.

You may have permissions on test, but do you have permissions on every other segment of your path? — MarsAtomic
yes, I have verified folder and file permissions. The test works invoked with su -c ... — user755
Verify that data, local and tmp are directories and that test is actually an exe (as opposed to a directory or some non-executable like a data file). — MarsAtomic
What OS are you using? I think it's clear now that the underlying problem is OS-related, as opposed to Java. This sounds like it's going to be something weird, like a file system mounted with noexec. I'm quickly moving out of my depth here, so I suggest trying unix.stackexchange.com. I assume when you used su you used root? — MarsAtomic

Lasse Bez Lasse Bez · Accepted Answer · 2021-02-03T13:10:30

You are using Android OS. I had a similar problem on RHEL. The secret was that SELINUX just LOVES to prevent stuff like this.

Check the log file /var/log/messages and search it for your executable name. You may find something similar to this: "SELinux is preventing pool-2-thread-1 from execute access on the file <your_exec_here>"

/data/local/tmp/test error=13, Permission denied

1 Answers