Return-Path: Received: from mail-db5eur01on0101.outbound.protection.outlook.com ([104.47.2.101]:11292 "EHLO EUR01-DB5-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751070AbeC0WG0 (ORCPT ); Tue, 27 Mar 2018 18:06:26 -0400 Date: Tue, 27 Mar 2018 23:06:14 +0100 (BST) From: Michael Young To: Eric Biggers , Herbert Xu cc: "J. Bruce Fields" , Jeff Layton , Trond Myklebust , Anna Schumaker , linux-nfs@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: NFS mounts failing when keytab present on client Message-ID: MIME-Version: 1.0 Content-Type: text/plain; format=flowed; charset=US-ASCII Sender: linux-nfs-owner@vger.kernel.org List-ID: NFS mounts stopped working on one of my computers after a kernel update from 4.15.3 to 4.15.4. I traced the problem to the commit [46e8d06e423c4f35eac7a8b677b713b3ec9b0684] crypto: hash - prevent using keyed hashes without setting key and a later kernel with this patch reverted works normally. The problem seems to be related to kerberos as the mount fails when the keytab is present, but works if I rename the keytab file. This is true even though the mount is with sec=sys . The mount should also work with sec=krb5 but that also fails in the same way. When the mount fails there are errors in dmesg like [ 1232.522816] gss_marshal: gss_get_mic FAILED (851968) [ 1232.522819] RPC: couldn't encode RPC header, exit EIO [ 1232.522856] gss_marshal: gss_get_mic FAILED (851968) [ 1232.522857] RPC: couldn't encode RPC header, exit EIO [ 1232.522863] NFS: nfs4_discover_server_trunking unhandled error -5. Exiting with error EIO [ 1232.525039] gss_marshal: gss_get_mic FAILED (851968) [ 1232.525042] RPC: couldn't encode RPC header, exit EIO Michael Young