Making Linux Protection Mechanisms Egalitarian with UserFS
Name
Zeldovich_Making Linux.pdf
Size
278.38 KB
Format
Adobe PDF
Checksum (MD5)
0382224e4d7520f7b6de4f22dc82c2cc
Author(s)
Kim, Taesoo
Zeldovich, Nickolai
Date Issued
August 2010
Journal
Proceedings of the 19th USENIX Security Symposium
Publisher
USENIX Association
Citation
Kim, Taesoo and Nickolai Zeldovich. "Making Linux Protection Mechanisms Egalitarian with UserFS." in Proceedings of the 19th USENIX Security Symposium, Washington, DC, Aug. 11-13, 2010.
Version
Author's final manuscript
Abstract
UserFS provides egalitarian OS protection mechanisms in Linux. UserFS allows any user—not just the system administrator—to allocate Unix user IDs, to use chroot, and to set up firewall rules in order to confine untrusted code. One key idea in UserFS is representing user IDs as files in a /proc-like file system, thus allowing applications to manage user IDs like any other files, by setting permissions and passing file descriptors over Unix domain sockets. UserFS addresses several challenges in making user IDs egalitarian, including accountability, resource allocation, persistence, and UID reuse. We have ported several applications to take advantage of UserFS; by changing just tens to hundreds of lines of code, we prevented attackers from exploiting application-level vulnerabilities, such as code injection or missing ACL checks in a PHP-based wiki application. Implementing UserFS requires minimal changes to the Linux kernel—a single 3,000-line kernel module—and incurs no performance overhead for most operations, making it practical to deploy on real systems.
Description
URL to paper on conference site: http://www.usenix.org/events/sec10/tech/
MIT Department
Massachusetts Institute of Technology. Computer Science and Artificial Intelligence Laboratory
Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike 3.0
Persistent DSpace Link
DOI of Published Version
http://www.usenix.org/events/sec10/tech/full_papers/Kim.pdf
