> On Oct 30, 2024, at 11:56 PM, Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > On Wed, Oct 30, 2024 at 08:44:26PM +0000, Song Liu wrote: >> Given bpf kfuncs can read user.* xattrs for almost a year now, I think we >> cannot simply revert it. We already have some users using it. >> >> Instead, we can work on a plan to deprecated it. How about we add a >> WARN_ON_ONCE as part of this patchset, and then remove user.* support >> after some time? > > As Christian mentioned having bpf access to user xattrs is probably > not a big issue. OTOH anything that makes security decisions based > on it is probably pretty broken. Not sure how you want to best > handle that. Agreed that we really need security.bpf prefix for security use cases. Reading user.* xattrs could be useful for some tracing use cases. We may also introduce other prefixes for future use cases. Thanks, Song