drm/amdgpu: reject ANONONLY userptrs that span multiple VMAs

For AMDGPU_GEM_USERPTR_ANONONLY, amdgpu_ttm_tt_get_user_pages() only
checks the VMA at the start of the range for a backing file, and
amdgpu_hmm_range_get_pages() then faults in the whole range, across any
other VMAs. The check used to reject ranges ending beyond the first VMA
(vma->vm_end < end), which got lost when the code moved to HMM.

An ANONONLY userptr over one page of file-backed memory is rejected
with -EPERM, but one over an anonymous page followed by the same
file-backed page is accepted.

Restore the check and reject ANONONLY userptrs that cross more than one
VMA. The second userptr is now rejected too.

v2: reject ranges spanning multiple VMAs instead of walking every VMA
    (Christian)
v3: cast num_pages to u64 to avoid an overflow (Christian)

Fixes: 6826cb3b92a3 ("drm/amdgpu: support userptr cross VMAs case with HMM")
Cc: Christian König <christian.koenig@amd.com>
Cc: Philip Yang <Philip.Yang@amd.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Jesse Zhang <Jesse.Zhang@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Acked-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 75d753ed4704d5efc72164d9e546b2a282e42ae2)
Cc: stable@vger.kernel.org

0 files changed, 0 insertions, 0 deletions