diff --git a/libavutil/opt.c b/libavutil/opt.c
index a892e056cb..60b0c2a946 100644
--- a/libavutil/opt.c
+++ b/libavutil/opt.c
@@ -949,6 +949,8 @@ int av_opt_set_chlayout(void *obj, const char *name,
 
     if (!o || !target_obj)
         return AVERROR_OPTION_NOT_FOUND;
+    if (o->flags & AV_OPT_FLAG_READONLY)
+        return AVERROR(EINVAL);
 
     dst = (AVChannelLayout*)((uint8_t*)target_obj + o->offset);