The Sylabs team has an exciting update regarding the recent PR_SET_NO_NEW_PRIVS security issue.
In collaboration with Cray, it has been discovered that the PR_SET_NO_NEW_PRIVS prctl() option is properly supported within the SLES11SP3 and CLE5 kernel. The reason it has been unsupported within Singularity (and other containers) is because the necessary user space dependencies are non-existent. This is good news, because we can directly declare these requirements within Singularity and properly use them within the kernel!
This modification has been added into the release-2.5 branch of Singularity in GitHub and it will be part of the next released version. If you need a supported version of Singularity that includes this feature and can securely support SLES11 and Cray’s CLE5 ASAP please contact Sylabs directly.
The fact remains that it is unsafe to run containers on host kernels that do not support PR_SET_NO_NEW_PRIVS but at least the problem set just shrunk! Great news for a Friday, and on that note, have a great weekend everyone!