tree 0c729322cbf3fa93566164482e646c5a2aad44bc
parent b5dcec693f87cb8475f2291c0075b2422addd3d6
author Jérôme Glisse <jglisse@redhat.com> 1461071271 -0400
committer Alex Deucher <alexander.deucher@amd.com> 1461283427 -0400

drm/amdgpu: forbid mapping of userptr bo through radeon device file

Allowing userptr bo which are basicly a list of page from some vma
(so either anonymous page or file backed page) would lead to serious
corruption of kernel structures and counters (because we overwrite
the page->mapping field when mapping buffer).

This will already block if the buffer was populated before anyone does
try to mmap it because then TTM_PAGE_FLAG_SG would be set in in the
ttm_tt flags. But that flag is check before ttm_tt_populate in the ttm
vm fault handler.

So to be safe just add a check to verify_access() callback.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>