GPL licensing on Linux has no effect on these sanctions.

Linux is a piece of software, owned by its individual authors and contributors, but published by Linus. Linus makes every decision about what is and is not in Linux.

Here’s how the “sanctions” usually work: the Office of Foreign Asset Control (OFAC) publishes a list called the Specially Designated Nationals (SDN) List. This list contains named individuals, businesses, and organizations that are not American (foreigners only. US Citizens are not supposed to be on the list). It is illegal for any US citizen or US business to transact business with anyone named on SDN. There are severe civil and criminal penalties for the US person if they’re not doing due diligence to check their international contacts against the list.

Now how does this affect Linux? It doesn’t affect Linux the project or any of the code. But it does mean that Linus the person can’t accept contributions from SDN persons. Linus’s lawyers have advised him that that would be a “business transaction” within the terms of the law.

Could Linus go in court make an argument that this sanctions regime violates his first amendment rights? Maybe. But I guarantee that would be a big hassle for him and Linux Foundation lawyers.

Could Linux the project restructure itself so that Linus the American is not making every decision on every contribution? Yes. But that would be a major change in organization.

And the records on the LKML seem to indicate that Linus and Linux leadership are at least politically indifferent to the sanctions in the first place, and possibly mildly supportive. So I doubt they’ll go to any major effort to change things up.

Edit: And finally I want to be clear on this point… Nothing is stopping sanctioned SDN entities from downloading a tarball off of kernel.org and making their own sanctions-busting GPL kernel with blackjack and hookers. That all seems perfectly legal to me.