uvesafb + grsecurity?

[nmp0906]

I am running the latest hardened toolchain from hardened-development overlay, keyworded ~amd64, no-multilib, hardened-sources system with grsecurity (and pax) enabled in the kernel. Now here's my issue:

With uvesafb:off appended to the kernel line, everything boots and runs fine.
With uvesafb:1680x1050-32,mttr:3,ywrap appended to the kernel line, things break:

Code: Select all

uvesafb: Getting VBE info block failed (eax=0x4f00, err=1)
uvesafb: vbe_init() failed with -22
uvesafb: probe of uvesafb.0 failed with error -22

Are there any known issues with uvesafb/v86d and grsecurity/pax enabled hardened kernels? If so, are there any known workarounds?

Thanks!

[s_e_a_n]

I realize this is a pretty old thread, but I never did find a clear answer to this question. The kernel option preventing v86d/uvesafb from working properly with a hardened kernel is GRKERNSEC_VM86 (Security Options---> Grsecurity---> Address Space Protection---> Restrict VM86 mode) . Uvesafb worked again after disabling this option, though it may not be a good idea to disable this on a hardened system: "The purpose of the option is to prevent exploitation of emulation errors in virtualization of vm86 mode like the one discovered in VMWare in 2009."

[mattst88]

Just use Kernel Modesetting. Forget about uvesafb.