On Fri, 2023-08-04 at 14:38 +0100, Mark Brown wrote: > On Wed, Aug 02, 2023 at 05:27:54PM +0100, Mark Brown wrote: > > On Tue, Aug 01, 2023 at 08:57:59PM +0000, Edgecombe, Rick P wrote: > > > > To make sure we are on the same page: What I'm saying is say we > > > do > > > something like add another flag SHADOW_STACK_SET_MARKER that > > > means add > > > a marker at the end (making the token off by one frame). Then you > > > can > > > just reject any flags != (SHADOW_STACK_SET_MARKER | > > > SHADOW_STACK_SET_TOKEN) value, and leave the rest of the code as > > > is. So > > > not really implementing anything new. > > > > Then x86 could use the same flag meanings if/when it implements > > > end > > > markers. If it doesn't seem worth it, it's not a big deal on my > > > end. > > > Just seemed that they were needlessly diverging. > > > Yes, my understanding of the flags is the same. I'll definitely > > implement omitting the cap since there's an actual use case for > > that > > (extending an existing stack, it's marginally safer to not have any > > opportunity to pivot into the newly allocated region). > > BTW are you planning to repost the series for this release? We're > almost at -rc5 which is pretty late and I didn't see anything yet. There were a few patches I posted on top of the last series after your comments, but I wasn't planning on reposting the whole thing. Why do you ask? Just trying to figure out the best version to base off of? > It > looks like there's a branch in tip that's getting some updates but > it's > not getting merged for -next. Hmm, not sure why it's not in -next anymore. I'll look into that. Thanks for pointing it out.