On Thu, Feb 9, 2023 at 7:15 PM Jens Axboe <axboe@xxxxxxxxx> wrote: > On 2/9/23 3:54 PM, Steve Grubb wrote: > > On Thursday, February 9, 2023 5:37:22 PM EST Paul Moore wrote: > >> On Thu, Feb 9, 2023 at 4:53 PM Richard Guy Briggs <rgb@xxxxxxxxxx> wrote: > >>> On 2023-02-01 16:18, Paul Moore wrote: > >>>> On Wed, Feb 1, 2023 at 3:34 PM Richard Guy Briggs <rgb@xxxxxxxxxx> > > wrote: > >>>>> fadvise and madvise both provide hints for caching or access pattern > >>>>> for file and memory respectively. Skip them. > >>>> > >>>> You forgot to update the first sentence in the commit description :/ > >>> > >>> I didn't forget. I updated that sentence to reflect the fact that the > >>> two should be treated similarly rather than differently. > >> > >> Ooookay. Can we at least agree that the commit description should be > >> rephrased to make it clear that the patch only adjusts madvise? Right > >> now I read the commit description and it sounds like you are adjusting > >> the behavior for both fadvise and madvise in this patch, which is not > >> true. > >> > >>>> I'm still looking for some type of statement that you've done some > >>>> homework on the IORING_OP_MADVISE case to ensure that it doesn't end > >>>> up calling into the LSM, see my previous emails on this. I need more > >>>> than "Steve told me to do this". > >>>> > >>>> I basically just want to see that some care and thought has gone into > >>>> this patch to verify it is correct and good. > >>> > >>> Steve suggested I look into a number of iouring ops. I looked at the > >>> description code and agreed that it wasn't necessary to audit madvise. > >>> The rationale for fadvise was detemined to have been conflated with > >>> fallocate and subsequently dropped. Steve also suggested a number of > >>> others and after investigation I decided that their current state was > >>> correct. *getxattr you've advised against, so it was dropped. It > >>> appears fewer modifications were necessary than originally suspected. > >> > >> My concern is that three of the four changes you initially proposed > >> were rejected, which gives me pause about the fourth. You mention > >> that based on your reading of madvise's description you feel auditing > >> isn't necessary - and you may be right - but based on our experience > >> so far with this patchset I would like to hear that you have properly > >> investigated all of the madvise code paths, and I would like that in > >> the commit description. > > > > I think you're being unnecessarily hard on this. Yes, the commit message > > might be touched up. But madvise is advisory in nature. It is not security > > relevant. And a grep through the security directory doesn't turn up any > > hooks. > > Agree, it's getting a bit anal... FWIW, patch looks fine to me. Call it whatever you want, but the details are often important at this level of code, and when I see a patch author pushing back on verifying that their patch is correct it makes me very skeptical. I really would have preferred that you held off from merging this until this was resolved and ACK'd ... oh well. -- paul-moore.com
