On Mon, Jan 27, 2025 at 11:39:44AM -0800, Eyal Birger wrote: > On Mon, Jan 27, 2025 at 11:33 AM Kees Cook <kees@xxxxxxxxxx> wrote: > > > > On Mon, Jan 27, 2025 at 11:24:02AM -0800, Eyal Birger wrote: > > > Hi Kees, > > > > > > On Mon, Jan 20, 2025 at 1:34 PM Kees Cook <kees@xxxxxxxxxx> wrote: > > > > > > > > On Sat, Jan 18, 2025 at 07:39:25PM -0800, Eyal Birger wrote: > > > > > Alternatively, maybe this syscall implementation should be reverted? > > > > > > > > Honestly, that seems the best choice. I don't think any thought was > > > > given to how it would interact with syscall interposers (including > > > > ptrace, strict mode seccomp, etc). > > > > > > I don't know if you noticed Andrii's and others' comments on this [1]. > > > > > > Given that: > > > - this issue requires immediate remediation > > > - there seems to be pushback for reverting the syscall implementation > > > - filtering uretprobe is not within the capabilities of seccomp without this > > > syscall (so reverting the syscall is equivalent to just passing it through > > > seccomp) > > > > > > is it possible to consider applying this current fix, with the possibility of > > > extending seccomp in the future to support filtering uretprobe if deemed > > > necessary (for example by allowing userspace to define a stricter policy)? > > > > I still think this is a Docker problem, but I agree that uretprobe > > without syscall is just as unfilterable as seccomp ignoring the syscall. > > > > Can you please update the patch to use the existing action_cache bitmaps > > instead of adding an open-coded check? We can consider adding > > syscall_restart to this as well in the future... > > I can. The main difference as far as I can tell is that it would not > apply to strict mode. Is that OK? it means that existing binaries using > strict mode would still crash if uretprobe is attached to them. Ah, good point. Please also add it to mode1_syscalls for strict. :) -- Kees Cook
