drm/i915/opregion: check port number bounds for SWSCI display power state
commit 24a644eb upstream. The mapping from enum port to whatever port numbering scheme is used by the SWSCI Display Power State Notification is odd, and the memory of it has faded. In any case, the parameter only has space for ports numbered [0..4], and UBSAN reports bit shift beyond it when the platform has port F or more. Since the SWSCI functionality is supposed to be obsolete for new platforms (i.e. ones that might have port F or more), just bail out early if the mapped and mangled port number is beyond what the Display Power State Notification can support. Fixes: 9c4b0a68 ("drm/i915: add opregion function to notify bios of encoder enable/disable") Cc: <stable@vger.kernel.org> # v3.13+ Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Lucas De Marchi <lucas.demarchi@intel.com> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/4800 Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/cc363f42d6b5a5932b6d218fefcc8bdfb15dbbe5.1644489329.git.jani.nikula@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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