ubuntu 10.10 ptrace权限的变动 | change in behavior of ptrace in ubuntu 10.10

最近有人在scanmem提交bug，说非root不能attach其他进程。当时我用的ubuntu 10.04，没能重现这个问题。最近用上10.10，发现确实有这个问题，于是考虑到是不是ubuntu的变动。简单搜了一下，在https://wiki.ubuntu.com/SecurityTeam/Roadmap/KernelHardening#ptrace%20Protection找到了原因，是10.10里故意这么设置的，目的是保护进程。

其作用的是/proc/sys/kernel/yama/ptrace_scope这个sysctl值，以前是0，ubuntu 10.10里默认是1。

于是scanmem以后需要root权限了。

而这个事情对于ubuntu是个好事情。

Recent some one has posted a bug in scanmem, that the program can no longer attach to other processes without run as root. At the moment I was still using ubuntu 10.04, where I couldn't reproduce the bug. Now I've been using 10.10 and I did confirm that bug. So I think this must be something changed in ubuntu. After a brief searching, I found the reason at https://wiki.ubuntu.com/SecurityTeam/Roadmap/KernelHardening#ptrace%20Protection, so that was changed intended, in order to protect the processes.

The key value is the sysctl value "/proc/sys/kernel/yama/ptrace_scope", which is 0 by default before, but now 1 by default.

So in the future scanmem will need to run as root.

And this is quite a good news for ubuntu.

Comments

A Rocky Migration: Moving from docker-compose to Podman and gVisor

I've been running a few containers for several years. They were all running under rootless Docker with a single user. Initially, I planned to migrate the containers to VMs , but I couldn't get a stable workflow after about two months of effort. Later, gVisor caught my attention , and I decided to migrate to Podman with gVisor instead. The new plan is to run each container with --userns=auto and use Quadlet for systemd integration. This approach provides better isolation and makes writing firewall rules easier. I'm now close to migrating all my containers. Here are a couple of rough edges I'd like to share. Network Layout I compared various networking options and spent a few hours trying the one-interface-per-group approach before giving up. I settled on a single macvlan network and decided to use static IP addresses for my containers. To prevent a randomly assigned IP address from conflicting with a predefined one, I allocated a large IP range for my ...

GameConqueror 0.09 -- Linux Game Hacking Tool

If you are a game hacker If you've been looking for a `CheatEngine for Linux` Then you can't miss this. ============================================== GameConqueror is a game hacking tool for linux, it's written in PyGTK and uses scanmem as its backend. It's supposed to be with most useful features of CheatEngine for Linux. Currently, I've implemented almost everything about scanning, involving variant data types and scan types: Data Types: int{8/16/32/64}, float{32/64}, unknown type(int or float) and unknown width(will try each of them), byte array and string Scan Types: equal, greater, less, changed, unchanged, increased(by), decreased(by) This should be enough for most cases, so I decided to release it at the current status. ============================================= Here's how you can get it PPA (for Ubuntu users) https://launchpad.net/~coolwanglu/+archive/scanmem (I've not test it in 32bit environments or Jaunty, do please inform me if it doe...

Exploring Immutable Distros and Declarative Management

My current server setup, based on Debian Stable and Docker, has served me reliably for years. It's stable, familiar, and gets the job done. However, an intriguing article I revisited recently about Fedora CoreOS, rpm-ostree, and OSTree native containers sparked my curiosity and sent me down a rabbit hole exploring alternative approaches to system management. Could there be a better way? Core Goals & Requirements Before diving into new technologies, I wanted to define what "better" means for my use case: The base operating system must update automatically and reliably. Hosted services (applications) should be updatable either automatically or manually, depending on the service. Configuration and data files need to be easy to modify, and crucially, automatically tracked and backed up. Current Setup: Debian Stable + Docker My current infrastructure consists of several servers, all running Debian Stable. System Updates are andled automatically via unattended-upgrades. Se...

WangLu's Notes

Search This Blog