Features/Syscall Filters

Syscall Filters

Summary

Syscall filtering is a security mechanism that allows applications to define which syscalls they should be allowed to execute.

Owner

• Name: Cole Robinson
• Email: crobinso@redhat.com
• Name: Paul Moore
• Email: pmoore@redhat.com

Current status

• Targeted release: Fedora 18
• Last updated: June 6 2012
• Percentage of completion: 40%

Benefit to Fedora

Improved security for applications that use syscall filtering.

Scope

• Get seccomp into upstream kernel: DONE, present in 3.5-rc1
• Package libseccomp for Fedora: IN PROGRESS (waiting on review), BZ 830992
• Get the QEMU/libseccomp patch accepted upstream: IN PROGRESS (v2 patch posted on June 13th by IBM)
• Update Fedora QEMU package to build against libseccomp: NOT DONE

How To Test

TBD

User Experience

Ideally this feature shouldn't be noticeable to the user, the syscall filtering should allow normal execution of the application. Intention is that only people trying to exploit security holes notice that the syscall they are trying to use is blocked :)

Dependencies

• Kernel updated to 3.5
• libseccomp packaged
• QEMU updated to 1.2

Any other apps that want to use this functionality need the the first two bits.

Contingency Plan

Since this is brand new functionality, if it doesn't make it in time for F18, nothing has changed. We just drop this feature page.

Documentation

• https://lwn.net/Articles/494252/ (article about syscall filtering)
• http://libseccomp.sf.net/ (helper library)
• https://lists.gnu.org/archive/html/qemu-devel/2012-05/msg00623.html (initial QEMU libseccomp patch posting)

Comments and Discussion

• See Talk:Features/Syscall_Filters