Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-qa0-f49.google.com ([209.85.216.49]:55217 "EHLO mail-qa0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756817Ab3KLVa5 (ORCPT ); Tue, 12 Nov 2013 16:30:57 -0500 Received: by mail-qa0-f49.google.com with SMTP id cm18so3233044qab.15 for ; Tue, 12 Nov 2013 13:30:57 -0800 (PST) From: Jeff Layton To: trond.myklebust@netapp.com Cc: linux-nfs@vger.kernel.org, chuck.lever@oracle.com, dros@netapp.com Subject: [PATCH] nfs: don't retry detect_trunking with RPC_AUTH_UNIX more than once Date: Tue, 12 Nov 2013 16:30:51 -0500 Message-Id: <1384291851-11154-1-git-send-email-jlayton@redhat.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: Currently, when we try to mount and get back NFS4ERR_CLID_IN_USE or NFS4ERR_WRONGSEC, we create a new rpc_clnt and then try the call again. There is no guarantee that doing so will work however, so we can end up retrying the call in an infinite loop. Worse yet, we create the new client using rpc_clone_client_set_auth, which creates the new client as a child of the old one. Thus, we can end up with a *very* long lineage of rpc_clnts. When we go to put all of the references to them, we can end up with a long call chain that can smash the stack as each rpc_free_client() call can recurse back into itself. This patch fixes this by simply ensuring that the SETCLIENTID call will only be retried in this situation if the last attempt did not use RPC_AUTH_UNIX. Cc: stable@vger.kernel.org # v3.10+ Cc: Weston Andros Adamson Cc: Chuck Lever Signed-off-by: Jeff Layton --- fs/nfs/nfs4state.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index c8e729d..4c26c01 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -2097,6 +2097,11 @@ again: break; case -NFS4ERR_CLID_INUSE: case -NFS4ERR_WRONGSEC: + /* No point in retrying if we already used RPC_AUTH_UNIX */ + if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX) { + status = -EPERM; + break; + } clnt = rpc_clone_client_set_auth(clnt, RPC_AUTH_UNIX); if (IS_ERR(clnt)) { status = PTR_ERR(clnt); -- 1.8.3.1