CODEWITHSUNDEEP
macossshremote-debugginglldbgdbserver
User 10482
User 10482

Reputation: 1012

Debugging with LLDB over SSH "error: process exited with status -1 (no such process.)" MacOS

I'm trying to debug an executable, that I manually built with clang, with lldb on MacOS host (ssh'd into) machine, through ssh. However, when I run it I get:

(lldb) error: process exited with status -1 (no such process.)

If I try the same with system executable like /bin/ls it works, perhaps because they are signed by Apple. My executable isn't signed so I tried self-signing it but no luck.

Experimenting more, I copied /bin/ls and resigned it with my own self-sign certificate which led to the same problem again! So, I believe this might be something to do with signing.

Other things that I have tried:

  1. Self-sign the executable. Followed instructions here https://developer.apple.com/library/archive/documentation/Security/Conceptual/CodeSigningGuide/Procedures/Procedures.html.
  2. Add entitlements following Xcode lldb can't attach to MacOS system program /bin/cp - "Not allowed to attach to process.".
  3. Run lldb with sudo.
  4. sudo DevToolsSecurity --enable
  5. spctl developer-mode enable-terminal

Why do the system executables work but not mine?

System details:

Darwin 23.4.0 Darwin Kernel Version 23.4.0: arm64 macOS 14: Sonoma

NOTE: I have checked other answers. This one lldb gives error "error: process exited with status -1 (Error 1)" comes close but is unresolved as seen in the follow up comments on the top answer.

EDIT 1: Dug more and generated logs. For the executable copied from /bin/ls the debugger is successful in attaching to it

[LaunchAttach] (93085) about to task_for_pid(93084)
108 +0.029169 sec [16b9d/0103]: ::task_for_pid ( target_tport = 0x0203, pid = 93084, &task ) => err = 0x00000000 (success) err = 0x00000000
[LaunchAttach] (93085) successfully task_for_pid(93084)'ed

but for my own executable it fails

[LaunchAttach] (93825) about to task_for_pid(93824)
error: [LaunchAttach] MachTask::TaskPortForProcessID task_for_pid(93824) failed: ::task_for_pid ( target_tport = 0x0203, pid = 93824, &task ) => err = 0x00000005 ((os/kern) failure)
109 +0.027093 sec [16e81/0103]: error: ::task_for_pid ( target_tport = 0x0203, pid = 93824, &task ) => err = 0x00000005 ((os/kern) failure) err = ::task_for_pid ( target_tport = 0x0203, pid = 93824, &task ) => err = 0x00000005 ((os/kern) failure) (0x00000005)

Both executables are in the same directory.

EDIT 2: More info.

I compiled a simple example (default console app examples) with Xcode and here's what I found experimenting with it.

ssh + lldb fails to get the task only when all of the following is true:

  1. executable is a x86_64 build. ARM build doesn't show the weird behavior.
  2. The executable is on a NFS filesystem mount (nfs, nodev, nosuid, automounted, nobrowse). If it's on a "normal" filesystem (apfs, NFS exported, local, journaled, nobrowse, protect, root data) somehow it works.

NOTE: If either is not true, the debugging works. For e.g. I can debug the same code on the NFS filesystem mount when compiled for ARM architecture.

#include <iostream>

int main() {
  std::cout << "Hello, World!\n";
  return 0;
}

The exe build by Xcode is signed and has the following entitlements.

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "https://www.apple.com/DTDs/PropertyList-1.0.dtd"><plist version="1.0"><dict><key>com.apple.application-identifier</key><string></string><key>com.apple.security.get-task-allow</key><true/></dict></plist>

Upvotes: 2

Views: 164

Answers (1)

Xiangyu Meng
Xiangyu Meng

Reputation: 31

You should try to enable developer mode.

Check status

DevToolsSecurity -status

Enable it

sudo DevToolsSecurity -enable

Check it again

DevToolsSecurity -status

Reference from this answer

Upvotes: 0

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