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Currently, RHEL 9 has libseccomp-2.5.0 which doesn't know about system calls added to recent versions of the Linux kernel.

For example, I see these commits after 2.5.0:

  syscalls: update the syscall table to v5.12-rc7 
  https://github.com/seccomp/libseccomp/commit/c56a00fe173a7dd5

  syscalls: add close_range() syscall 
  https://github.com/seccomp/libseccomp/commit/ac849e7960547d41

  syscalls: update to Linux v5.14-rc7
  https://github.com/seccomp/libseccomp/commit/c3559610ffdcda23

I see that the CentOS Stream dist-git has Linux 5.14.0 and I see corresponding builds in Brew, so this seems relevant.

I noticed this while working on fixing CVE-2021-41133 (bug 2012245) for Flatpak, both upstream and for Fedora and RHEL.

In certain situations, Flatpak receives -EFAULT from seccomp_rule_add() if libseccomp doesn't know about the system call.  To avoid user-visible breakage, Flatpak ignores that and keeps going.  However, if the user is running a kernel that's new enough to have that system call, then this means that Flatpak doesn't block the call, leaving a gap in its sandbox.

Having a newer libseccomp will make our lives easier when evaluating the security impact and fixes for the next CVE that rolls in, by reducing the number of different kernel/libseccomp combinations.

Updating from 2.5.0 to 2.5.2 should be pretty safe, and we now have similar updates for Fedora >= 33.

Note that RHEL 8 already has libseccomp-2.5.1 (bug 1927635) since RHEL 8.4.  So, currently, RHEL 8 is shipping newer code than RHEL 9.  :)

Thanks for working on this!

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (new packages: libseccomp), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHEA-2022:3969