Kees Cook <keesc...@chromium.org> writes: > On Tue, May 16, 2017 at 4:09 AM, Michael Ellerman <m...@ellerman.id.au> wrote: >> Yeah it looks like powerpc also suffers from the same bug that arm64 >> used to, ie. virt_addr_valid() will return true for some vmalloc >> addresses. >> >> virt_addr_valid() is used pretty widely, I'm not sure if we can just fix >> it without other fallout. I'll dig a bit more tomorrow if no one beats >> me to it. >> >> Kees, depending on how that turns out we may ask you to revert >> 517e1fbeb65f ("mm/usercopy: Drop extra is_vmalloc_or_module() check"). > > That's fine by me. Let me know what you think would be best.
Oh man, what a mess. I think we can do a small fix for this in powerpc code for 4.12, will post it soon for Breno to test - I still can't reproduce locally. cheers