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[Launchpad Bug Tracker <1197133@xxxxxxxxxxxxxxxxxx>]

Jamie Strandboge (jdstrand) has assigned this bug to you for lxc-android-config in Ubuntu Saucy:

SDK applications need a bunch of hardware specific accesses to graphics
devices. Eg, the ubuntu-sdk AppArmor template has:

  # FIXME: Nexus7 (grouper)
  /dev/nvmap rw,
  /dev/nvhost-* rw,
  /sys/module/nvhost/parameters/* r,
  /sys/module/fuse/parameters/tegra* r,

  # FIXME: Galaxy Nexus specific (maguro)
  /dev/pvrsrvkm rw,

  # FIXME: Nexus 4 (mako)
  /dev/kgsl-3d0 rw,
  /dev/ion rw,

  # FIXME: Nexus 10 (manta)
  /dev/mali[0-9] rw,
  /dev/ion rw,

  # FIXME: nvidia (we could use the nvidia abstraction, but it needs ipc_lock
  # so lets avoid that for now. Note, ~/.nv/GLCache is used unless
  # __GL_SHADER_DISK_CACHE_PATH is set
  /dev/nvidia[0-9] rw,
  /dev/nvidiactl rw,

This is a maintenance nightmare because the devices don't live under a
directory (like we have with /dev/dri/ and /dev/snd) but instead in the
toplevel /dev directory (how can we possibly keep track of all the
devices?). This also makes porting very difficult because the devices
could be anything. Furthermore, the write accesses allow applications to
attack these devices directly. The current behavior weakens our
application confinement policy as well as making it hard to maintain.

The best solution would be to have the access to the devices happen via
an out of process helper (eg Mir) and use shared memory (or similar,
like on Android) to provide access. This type of architecture could also
allow for writes but not reads, which could be useful for other things
like DRM.

In the meantime, we could solve the maintenance and ports issue by simply creating all these devices under a specific directory in /dev, such as /dev/graphics, and then our apparmor policy would simply have:
  /dev/graphics/* rw,

** Affects: touch-preview-images
     Importance: Undecided
         Status: New

** Affects: apparmor-easyprof-ubuntu (Ubuntu)
     Importance: Undecided
         Status: Triaged

** Affects: lxc-android-config (Ubuntu)
     Importance: High
     Assignee: Ubuntu Phonedations bugs (ubuntu-phonedations-bugs)
         Status: Confirmed

** Affects: apparmor-easyprof-ubuntu (Ubuntu Saucy)
     Importance: Undecided
         Status: Triaged

** Affects: lxc-android-config (Ubuntu Saucy)
     Importance: High
     Assignee: Ubuntu Phonedations bugs (ubuntu-phonedations-bugs)
         Status: Confirmed


** Tags: application-confinement
-- 
SDK applications require hardware-specific direct access to graphics devices
https://bugs.launchpad.net/bugs/1197133
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