diff --git a/libavformat/avio.c b/libavformat/avio.c
index 074d3eeb86..0702aff007 100644
--- a/libavformat/avio.c
+++ b/libavformat/avio.c
@@ -289,14 +289,14 @@ static inline int retry_transfer_wrapper(URLContext *h, unsigned char *buf, int
 
 int ffurl_read(URLContext *h, unsigned char *buf, int size)
 {
-    if (h->flags & AVIO_FLAG_WRITE)
+    if (!(h->flags & AVIO_FLAG_READ))
         return AVERROR(EIO);
     return retry_transfer_wrapper(h, buf, size, 1, h->prot->url_read);
 }
 
 int ffurl_read_complete(URLContext *h, unsigned char *buf, int size)
 {
-    if (h->flags & AVIO_FLAG_WRITE)
+    if (!(h->flags & AVIO_FLAG_READ))
         return AVERROR(EIO);
     return retry_transfer_wrapper(h, buf, size, size, h->prot->url_read);
 }