NFSv4.2: decode_read_plus_data() must skip padding after data segment

All XDR opaque object sizes are 32-bit aligned, and a data segment is no
exception.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

fs/nfs/nfs42xdr.c

@@ -1038,7 +1038,9 @@ static int decode_read_plus_data(struct xdr_stream *xdr, struct nfs_pgio_res *re
 
 	p = xdr_decode_hyper(p, &offset);
 	count = be32_to_cpup(p);
-	recvd = xdr_align_data(xdr, res->count, count);
+	recvd = xdr_align_data(xdr, res->count, xdr_align_size(count));
+	if (recvd > count)
+		recvd = count;
 	res->count += recvd;
 
 	if (count > recvd) {