On Tue, Aug 13, 2024 at 01:08:29PM +0200, Andi Shyti wrote:
Commit 8bdd9ef7e9b1b2a73e394712b72b22055e0e26c3 upstream.
Calculating the size of the mapped area as the lesser value between the requested size and the actual size does not consider the partial mapping offset. This can cause page fault access.
Fix the calculation of the starting and ending addresses, the total size is now deduced from the difference between the end and start addresses.
Additionally, the calculations have been rewritten in a clearer and more understandable form.
Fixes: c58305af1835 ("drm/i915: Use remap_io_mapping() to prefault all PTE in a single pass") Reported-by: Jann Horn jannh@google.com Co-developed-by: Chris Wilson chris.p.wilson@linux.intel.com Signed-off-by: Chris Wilson chris.p.wilson@linux.intel.com Signed-off-by: Andi Shyti andi.shyti@linux.intel.com Cc: Joonas Lahtinen joonas.lahtinen@linux.intel.com Cc: Matthew Auld matthew.auld@intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: stable@vger.kernel.org # v4.9+ Reviewed-by: Jann Horn jannh@google.com Reviewed-by: Jonathan Cavitt Jonathan.cavitt@intel.com [Joonas: Add Requires: tag] Requires: 60a2066c5005 ("drm/i915/gem: Adjust vma offset for framebuffer mmap offset") Signed-off-by: Joonas Lahtinen joonas.lahtinen@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20240802083850.103694-3-andi.s... (cherry picked from commit 97b6784753da06d9d40232328efc5c5367e53417) Signed-off-by: Joonas Lahtinen joonas.lahtinen@linux.intel.com
drivers/gpu/drm/i915/gem/i915_gem_mman.c | 53 +++++++++++++++++++++--- 1 file changed, 47 insertions(+), 6 deletions(-)
Now queued up, thanks.
greg k-h