[MESOS-6504] Use 'geteuid()' for the root privileges check.

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.2.0
• Component/s: containerization
• Labels: backend isolator mesosphere user
• Target Version/s: 1.2.0
• Epic Link: Unified Container
• Sprint: Mesosphere Sprint 47, Mesosphere Sprint 48, Mesosphere Sprint 50
• Story Points: 3
• Assignee: Gilbert Song
• Reporter: Gilbert Song
• Shepherd: Jie Yu
• Created: 28/Oct/16 20:40
• Updated: 26/Apr/17 16:54
• Resolved: 22/Jan/17 19:23

Description

Currently, parts of code in Mesos check the root privileges using os::user() to compare to "root", which is not sufficient, since it compares the real user. When people change the mesos binary by 'setuid root', the process may not have the right permission to execute.

We should check the effective user id instead in our code.