[Lldb-commits] [lldb] [lldb][Android] Fix platform process list regression (PR #164333)

[Emre Kultursay via lldb-commits]

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@@ -652,75 +709,169 @@ PlatformAndroid::FindProcesses(const ProcessInstanceInfoMatch &match_info,
     return 0;
   }
 
-  // Use 'pidof' command to get PIDs for the process name.
-  // Quote the process name to handle special characters (spaces, etc.)
-  std::string pidof_output;
-  StreamString command;
-  command.Printf("pidof '%s'", process_name.c_str());
-  error = adb->Shell(command.GetData(), seconds(5), &pidof_output);
+  std::string ps_output;
+  error = adb->Shell("ps -A -o PID,ARGS", seconds(5), &ps_output);
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emrekultursay wrote:

> Agreed. It would be surprising to me if I ran `platform process list` and it applied some kind of extra filtering.

That is the Android (Linux) security model.

- Android sets `hidepid=2` https://android.googlesource.com/platform/system/core/+/c39ba5a

- Here's hidepid semantics:  https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=0499680a42141d86417a8fbaa8c8db806bea1201

On Android, when running inside a process/package, you are not **supposed to** see other processes, by design. 
- When lldb-server runs inside a package/user, it should only see the processes in the package.
- When lldb-server runs as shell or root on the Android device, it will already have access to all process on the system. 

By using this adb-based approach, you are bypassing the security model. On a non-Android Linux machine that was configured with hidepid=2, I don't think you will see processes from other users. That means this PR is actually introducing behavior that is inconsistent across Android and Linux (and goes against the security model).




https://github.com/llvm/llvm-project/pull/164333