Hello, Leo Famulari <l...@famulari.name> skribis:
> On Wed, Jan 10, 2018 at 05:39:59AM +0800, Alex Vong wrote: >> I have an idea. Should we add a news entry to Guix blog[0] summarizing >> all the above? For example, we can advice users to install noscript and >> turn off javascript by default and only enable it on trusted site when >> necessary. > > I think it's a good idea to publish an advisory of some sort but I don't > know if I'll have time in the next few days to write it. It’s a good idea. I think the message you sent at the beginning of this thread would be a good start. Not much more needs to be added at this point, IMO. >> About the "Retpoline" mitigation technique[1]. Right now only GCC 7.2.0 >> is patched, but our default gcc version is 5.4.0 in master and 5.5.0 in >> core-updates. So I tried to apply the patches apply the patches to >> 5.5.0. There are totally 17 commits/patches. The first 3 patch can be >> modified to work while the 4th patch cannot be easily modified to work >> because the function ``ix86_nopic_noplt_attribute_p'' is not present on >> 5.5.0. Perhaps discarding the hunk would be fine, but we need to be >> careful about it (maybe running tests make sure the fix really works). >> >> Do you think we should modify the patch to make it work on GCC 5 or >> update core-updates to GCC 7 instead? > > So far I haven't had time to read about Retpoline, how it works, and the > degree to which other mitigations work without it. So the following > opinion is from a place of ignorance. I'm very interested to hear what > everyone else thinks about your suggestion. > > Having said that, my opinion is that it's too late in this core-updates > cycle to change the default GCC version, especially two major versions, > from 5 to 7. No doubt about it. :-) > Something we can do very easily, even on the master branch, is to build > specific packages with GCC 7, assuming the Retpoline technique would be > effective in that context. Yes, I see Alex submitted a patch already. Thanks, Ludo’.
