Fix Collada: Avoid unnecessary and even wrong check on unavailable data

The function validateConstraints() potentially causes a null pointer
exception. I changed this so that the function returns a failure as soon
as the validation fails. This avoids falling into the null pointer trap.

1 files changed, 12 insertions, 6 deletions

diff --git a/source/blender/collada/AnimationExporter.cpp b/source/blender/collada/AnimationExporter.cpp
index 97d3b6b29b8..5492fcbb625 100644
--- a/source/blender/collada/AnimationExporter.cpp
+++ b/source/blender/collada/AnimationExporter.cpp
@@ -1926,15 +1926,21 @@ void AnimationExporter::sample_animation(float *v, std::vector<float> &frames, i
 
 bool AnimationExporter::validateConstraints(bConstraint *con)
 {
-	bool valid = true;
 	const bConstraintTypeInfo *cti = BKE_constraint_typeinfo_get(con);
 	/* these we can skip completely (invalid constraints...) */
-	if (cti == NULL) valid = false;
-	if (con->flag & (CONSTRAINT_DISABLE | CONSTRAINT_OFF)) valid = false;
+	if (cti == NULL)
+		return false;
+	if (con->flag & (CONSTRAINT_DISABLE | CONSTRAINT_OFF))
+		return false;
+
 	/* these constraints can't be evaluated anyway */
-	if (cti->evaluate_constraint == NULL) valid = false;
+	if (cti->evaluate_constraint == NULL)
+		return false;
+
 	/* influence == 0 should be ignored */
-	if (con->enforce == 0.0f) valid = false;
+	if (con->enforce == 0.0f)
+		return false;
 
-	return valid;
+	/* validation passed */
+	return true;
 }