On Sat, Oct 08, 2022 at 09:03:28PM -0700, Kees Cook wrote: > On Sun, Oct 09, 2022 at 03:05:17PM +1300, Paulo Miguel Almeida wrote: > > On Sat, Oct 08, 2022 at 05:18:35PM -0700, Kees Cook wrote: > > > This is allocating 1 more byte than before, since the struct size didn't > > > change. But this has always allocated too much space, due to the struct > > > padding. For a "no binary changes" patch, the above "+ 1" needs to be > > > left off. > > > > That's true. I agree that leaving "+ 1" would work and produce a > > no-binary-changes patch due to the existing padding that the structure > > has. OTOH, I thought that relying on that space could bite us in the > > future if anyone tweaks the struct again...so my reaction was to ensure > > that the NUL-terminator space was always guaranteed to be there. > > Hence, the change on c693 (objdump above). > > > > What do you think? Should we keep or leave the above > > "+ 1" after the rationale above? > > I think it depends on what's expected from this allocation. Christine or > David, can you speak to this?
Hi, thanks for picking through that. Most likely the intention was to allow up to 64 (DLM_LOCKSPACE_LEN) character names, and then use the ls_name[1] for the terminating byte. I'd be happy to take the patch replacing the one-element name. Or, if you'd like to drop it, then we'll eliminate it along with a cleanup of name/namelen more broadly. Dave
