--- a/sys/vfs/isofs/cd9660/cd9660_vnops.c
+++ b/sys/vfs/isofs/cd9660/cd9660_vnops.c
@@ -471,6 +471,7 @@
 	}
 	idp->eofflag = 1;
 	idp->curroff = uio->uio_offset;
+	idp->uio_off = uio->uio_offset;
 
 	if ((entryoffsetinblock = idp->curroff & bmask) &&
 	    (error = cd9660_devblkatoff(vdp, idp->curroff, NULL, &bp))) {