On Fri, 11 Oct 2019 14:00:50 -0700 Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> wrote: > On Fri, Oct 11, 2019 at 1:55 PM Steven Rostedt <rostedt@xxxxxxxxxxx> wrote: > > > > I guess I can keep it this way. Thoughts? > > That looks fine to me. I'm still not sure you actually need to do all > this, but it doesn't look _wrong_. Yep, I sent this before seeing your other email. > > That said, I still do think that if things are locked down from the > very get-go, tracefs_create_file() shouldn't even create the files. Agreed. I forgot to add in my last email: 4) Add the lockdown check to create_file() > > That's mostly an independent thing from the "what about if they exists > and things got locked down afterwards", though. Well, I'll be combining it with the tracing_disabled code, which was there originally to prevent corrupted buffers from causing harm by being read. > > I do wonder about the whole "well, if you started tracing before > locking things down, don't you want to see the end results"? > I don't think it hurts to disable it. Although, I don't think reading the trace event formats will be a issue. I'm not aware of any of them from giving too much info to the system. And if you really do care about that, do it at boot up, and with the create_file part, it wont have any files to read. -- Steve
