Zack's Kernel News
Zack's Kernel News
Chronicler Zack Brown reports on the latest news, views, dilemmas, and developments within the Linux kernel community.
Inheriting Filesystem Capabilities
Christoph Lameter posted a patch to make filesystem capabilities inheritable the way the SUID bit is. When you set the SUID bit in an executable and another user runs that executable, it runs with your permissions, rather than the permissions of that user. Any files it creates, or other programs it invokes, are likewise run as you instead of as that user.
Capabilities don't have that kind of inheritability. So, if you write a script and give it certain capabilities, such as allowing raw network access, any scripts invoked by that script will not have the capability to do raw network access. Thus, the script would not be able to rely on any other tools to help do that part of its work. Christoph said, "This is behavior that is counterintuitive to the expected behavior of processes in Unix."
Making capabilities inheritable, Christoph said, was preferable to simply running executables with the SUID bit set. The SUID bit is a very blunt tool, giving the executable *all* the permissions of its owner; whereas capabilities are more surgical, allowing you to constrain those permissions to just the set what is needed.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
Kali Linux Waxes Nostalgic with BackTrack Mode
For those who've used Kali Linux since its inception, the changes with the new release are sure to put a smile on your face.
-
Gnome 50 Smooths Out NVIDIA GPU Issues
Gamers rejoice, your favorite pastime just got better with Gnome 50 and NVIDIA GPUs.
-
System76 Retools Thelio Desktop
The new Thelio Mira has landed with improved performance, repairability, and front-facing ports alongside a high-quality tempered glass facade.
-
Some Linux Distros Skirt Age Verification Laws
After California introduced an age verification law recently, open source operating system developers have had to get creative with how they deal with it.
-
UN Creates Open Source Portal
In a quest to strengthen open source collaboration, the United Nations Office of Information and Communications Technology has created a new portal.
-
Latest Linux Kernel RC Contains Changes Galore
Linux kernel 7.0-rc3 includes more changes than have been made in a single release in recent history.
-
Nitrux 6.0 Now Ready to Rock Your World
The latest iteration of the Debian-based distribution includes all kinds of newness.
-
Linux Foundation Reports that Open Source Delivers Better ROI
In a report that may surprise no one in the Linux community, the Linux Foundation found that businesses are finding a 5X return on investment with open source software.
-
Keep Android Open
Google has announced that, soon, anyone looking to develop Android apps will have to first register centrally with Google.
-
Kernel 7.0 Now in Testing
Linus Torvalds has announced the first Release Candidate (RC) for the 7.x kernel is available for those who want to test it.