[PATCH v6 5/9] drm/i915/display: Handle invalid fb_modifier in intel_fb_modifier_to_tiling

[Jouni Högander]

Lookup_modifier is returning INTEL_PLANE_CAP_TILING_4 on invalid
fb_modifier value. Use lookup_modifier_or_null in
intel_fb_modifier_to_tiling and return I915_TILING_NONE in case
lookup_modifier_or_null returns null.

Signed-off-by: Jouni Högander <jouni.hogander at intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231203114840.841311-4-jouni.hogander@intel.com
(cherry picked from commit c61d8f7baabad322d53db301f7afaa2ce41493e6)
Acked-by: Jani Nikula <jani.nikula at intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_fb.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_fb.c b/drivers/gpu/drm/i915/display/intel_fb.c
index f42a693f96c1..20d58a021a42 100644
--- a/drivers/gpu/drm/i915/display/intel_fb.c
+++ b/drivers/gpu/drm/i915/display/intel_fb.c
@@ -303,7 +303,14 @@ lookup_format_info(const struct drm_format_info formats[],
 
 unsigned int intel_fb_modifier_to_tiling(u64 fb_modifier)
 {
-	u8 tiling_caps = lookup_modifier(fb_modifier)->plane_caps &
+	const struct intel_modifier_desc *md;
+	u8 tiling_caps;
+
+	md = lookup_modifier_or_null(fb_modifier);
+	if (!md)
+		return I915_TILING_NONE;
+
+	tiling_caps = lookup_modifier_or_null(fb_modifier)->plane_caps &
 			 INTEL_PLANE_CAP_TILING_MASK;
 
 	switch (tiling_caps) {
-- 
2.34.1