Bug 298988 – app-emulation/virtualbox-guest-additions: various kernel module problems

• Product: Gentoo Linux
• Status: RESOLVED FIXED

[Description PaX Team 2009-12-30 15:28:14 UTC]

recently while playing with vbox i ran into two issues, one that manifests under PaX/KERNEXEC and another that should affect everyone.

the first one is related to some logger code in vbox modules that on i386 (but not on amd64) use some runtime generated stubs for no good reason as according to the comments in the code, that trickery was needed for non-C99 compilers but i don't think anyone's using such on gentoo these days. so the first proposed patch will simply add enforce LOG_USE_C99 when compiling the kernel modules and it works well.

the second issue appears to be a genuine vboxvfs driver bug where some (recent?) linux changes weren't followed up in the code and that results in a NULL ptr dereference when mounting shared folders in a linux guest. the patch works for me with 2.6.32.x but i didn't check which exact linux version this new code should depend on, that's something for someone else/upstream to figure out ;).

Reproducible: Always

[Comment 1 PaX Team 2009-12-30 15:29:25 UTC]

Created attachment 214628 [details, diff]
force C99 based logger code

[Comment 2 PaX Team 2009-12-30 15:30:36 UTC]

Created attachment 214629 [details, diff]
add backing_dev_info init/destroy calls to vboxvfs

[Comment 3 PaX Team 2010-01-29 12:09:20 UTC]

upstream bug with a bad fix: http://www.virtualbox.org/ticket/5891. guys, can you please take a look at these patches in a more timely manner?

[Comment 4 Jim Ramsay (lack) (RETIRED) 2010-05-11 19:02:40 UTC]

(In reply to comment #3)
> upstream bug with a bad fix: http://www.virtualbox.org/ticket/5891. guys, can
> you please take a look at these patches in a more timely manner?

So if I'm reading the upstream bug properly, their fix in 3.1.4 fixes the same issue as your 'vboxvfs-fix-bdi-init.patch' issue, but they have not fixed the 'vboxguest-log-use-c99.patch' issue.  Is this correct?

[Comment 5 PaX Team 2010-05-11 19:15:21 UTC]

(In reply to comment #4)
> So if I'm reading the upstream bug properly, their fix in 3.1.4 fixes the same
> issue as your 'vboxvfs-fix-bdi-init.patch' issue,

yes, in fact that's a better fix as mine wasn't correct for multiple vboxvfs mounts.

> but they have not fixed the
> 'vboxguest-log-use-c99.patch' issue.  Is this correct?

correct, that patch would still be nice to have in gentoo (not sure upstream cares about PaX specific issues, but at least hardened gentoo definitely does i think ;).

[Comment 6 Lars Wendler (Polynomial-C) (RETIRED) 2010-06-08 17:51:56 UTC]

+  08 Jun 2010; Lars Wendler <[e-mail]>
+  +files/vboxguest-log-use-c99.patch,
+  virtualbox-guest-additions-3.1.8-r2.ebuild,
+  virtualbox-guest-additions-3.2.2.ebuild,
+  virtualbox-guest-additions-3.2.4.ebuild,
+  -files/virtualbox-guest-additions-5.initd,
+  -files/virtualbox-guest-additions-6.initd:
+  Added a patch from PaX Team (bug #298988). Removed unused files.
+