Return-Path: Received: from mx2.suse.de ([195.135.220.15]:38523 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751012AbeBSFEf (ORCPT ); Mon, 19 Feb 2018 00:04:35 -0500 From: NeilBrown To: Trond Myklebust , Anna Schumaker Date: Mon, 19 Feb 2018 16:02:29 +1100 Subject: [PATCH 14/23] SUNRPC: add side channel to use non-generic cred for rpc call. Cc: linux-nfs@vger.kernel.org Message-ID: <151901654925.17421.8083987724119246673.stgit@noble> In-Reply-To: <151901634940.17421.7637564368419392071.stgit@noble> References: <151901634940.17421.7637564368419392071.stgit@noble> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: The credential passed in rpc_message.rpc_cred is always a generic credential except in one instance. When gss_destroying_context() calls rpc_call_null(), it passes a specific credential that it needs to destroy. In this case the RPC acts *on* the credential rather than being authorized by it. This special case deserves explicit support and providing that will mean that rpc_message.rpc_cred is *always* generic, allowing some optimizations. So add "tk_op_cred" to rpc_task and "rpc_op_cred" to the setup data. Use this to pass the cred down from rpc_call_null(), and have rpcauth_bindcred() notice it and bind it in place. Signed-off-by: NeilBrown CHANGES: add missing 'else' in rpcauth_bindcred() A subsequent patch added this before. --- include/linux/sunrpc/sched.h | 2 ++ net/sunrpc/auth.c | 6 +++++- net/sunrpc/clnt.c | 2 +- net/sunrpc/sched.c | 3 +++ 4 files changed, 11 insertions(+), 2 deletions(-) diff --git a/include/linux/sunrpc/sched.h b/include/linux/sunrpc/sched.h index 216b6a7513db..be278d92ff4f 100644 --- a/include/linux/sunrpc/sched.h +++ b/include/linux/sunrpc/sched.h @@ -71,6 +71,7 @@ struct rpc_task { struct rpc_clnt * tk_client; /* RPC client */ struct rpc_xprt * tk_xprt; /* Transport */ + struct rpc_cred * tk_op_cred; /* cred being operated on */ struct rpc_rqst * tk_rqstp; /* RPC request */ @@ -105,6 +106,7 @@ struct rpc_task_setup { struct rpc_task *task; struct rpc_clnt *rpc_client; struct rpc_xprt *rpc_xprt; + struct rpc_cred *rpc_op_cred; /* credential being operated on */ const struct rpc_message *rpc_message; const struct rpc_call_ops *callback_ops; void *callback_data; diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c index 484a850a7e00..0130d0151623 100644 --- a/net/sunrpc/auth.c +++ b/net/sunrpc/auth.c @@ -726,7 +726,11 @@ rpcauth_bindcred(struct rpc_task *task, struct rpc_cred *cred, int flags) if (flags & RPC_TASK_ASYNC) lookupflags |= RPCAUTH_LOOKUP_NEW; - if (cred != NULL && cred != &machine_cred) + if (task->tk_op_cred) + /* Task must use exactly this rpc_cred */ + new = task->tk_op_cred->cr_ops->crbind(task, task->tk_op_cred, + lookupflags); + else if (cred != NULL && cred != &machine_cred) new = cred->cr_ops->crbind(task, cred, lookupflags); else if (cred == &machine_cred) new = rpcauth_bind_machine_cred(task, lookupflags); diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c index 85db88bfb4c8..be66fec601b0 100644 --- a/net/sunrpc/clnt.c +++ b/net/sunrpc/clnt.c @@ -2516,12 +2516,12 @@ struct rpc_task *rpc_call_null_helper(struct rpc_clnt *clnt, { struct rpc_message msg = { .rpc_proc = &rpcproc_null, - .rpc_cred = cred, }; struct rpc_task_setup task_setup_data = { .rpc_client = clnt, .rpc_xprt = xprt, .rpc_message = &msg, + .rpc_op_cred = cred, .callback_ops = (ops != NULL) ? ops : &rpc_default_ops, .callback_data = data, .flags = flags, diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c index d9db2eab3a8d..d0091e5ad220 100644 --- a/net/sunrpc/sched.c +++ b/net/sunrpc/sched.c @@ -949,6 +949,8 @@ static void rpc_init_task(struct rpc_task *task, const struct rpc_task_setup *ta task->tk_xprt = xprt_get(task_setup_data->rpc_xprt); + task->tk_op_cred = get_rpccred(task_setup_data->rpc_op_cred); + if (task->tk_ops->rpc_call_prepare != NULL) task->tk_action = rpc_prepare_task; @@ -1007,6 +1009,7 @@ static void rpc_free_task(struct rpc_task *task) unsigned short tk_flags = task->tk_flags; rpc_release_calldata(task->tk_ops, task->tk_calldata); + put_rpccred(task->tk_op_cred); if (tk_flags & RPC_TASK_DYNAMIC) { dprintk("RPC: %5u freeing task\n", task->tk_pid);