Hi Kees, Thanks for your review - I will incorporate what I can into v3, or explain why not once I give it a try :). On Thu, 2020-05-21 at 14:08 -0700, Kees Cook wrote: > > <snip> > On Thu, May 21, 2020 at 09:56:38AM -0700, Kristen Carlson Accardi > wrote: > > + /* > > + * sometimes we are updating a relative offset that would > > + * normally be relative to the next instruction (such as a > > call). > > + * In this case to calculate the target, you need to add 32bits > > to > > + * the pc to get the next instruction value. However, sometimes > > + * targets are just data that was stored in a table such as > > ksymtab > > + * or cpu alternatives. In this case our target is not relative > > to > > + * the next instruction. > > + */ > > Excellent and scary comment. ;) Was this found by trial and error? > That > sounds "fun" to debug. :P This did suck to debug. Thank goodness for debugging with gdb in a VM. As you know, I had previously had a patch to use a prand to be able to retain the same layout across boots, and that came in handy here. While we decided to not submit this functionality with this initial merge attempt, I will add it on in the future as it does make debugging much easier when you can reliably duplicate failure modes.
