From: Trond Myklebust <trond.myklebust@primarydata.com>
Date: Mon, 19 Dec 2016 15:23:10 +0000 (-0500)
Subject: NFSv4: Retry the DELEGRETURN if the embedded GETATTR is rejected with EACCES
X-Git-Tag: v4.14-rc1~1804^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=8ac2b42238f549241a4755de40fd161fba3de438;p=platform%2Fkernel%2Flinux-rpi.git

NFSv4: Retry the DELEGRETURN if the embedded GETATTR is rejected with EACCES

If our DELEGRETURN RPC call is rejected with an EACCES call, then we should
remove the GETATTR call from the compound RPC and retry.
This could potentially happen when there is a conflict between an
ACL denying attribute reads and our use of SP4_MACH_CRED.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
---

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 4b66b0c..6dcbc5d 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -5695,6 +5695,14 @@ static void nfs4_delegreturn_done(struct rpc_task *task, void *calldata)
 	case -NFS4ERR_STALE_STATEID:
 		task->tk_status = 0;
 		break;
+	case -NFS4ERR_ACCESS:
+		if (data->args.bitmask) {
+			data->args.bitmask = NULL;
+			data->res.fattr = NULL;
+			task->tk_status = 0;
+			rpc_restart_call_prepare(task);
+			return;
+		}
 	default:
 		if (nfs4_async_handle_error(task, data->res.server,
 					    NULL, NULL) == -EAGAIN) {
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index 6f2365b..e9255cb 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -2705,7 +2705,8 @@ static void nfs4_xdr_enc_delegreturn(struct rpc_rqst *req,
 	encode_putfh(xdr, args->fhandle, &hdr);
 	if (args->lr_args)
 		encode_layoutreturn(xdr, args->lr_args, &hdr);
-	encode_getfattr(xdr, args->bitmask, &hdr);
+	if (args->bitmask)
+		encode_getfattr(xdr, args->bitmask, &hdr);
 	encode_delegreturn(xdr, args->stateid, &hdr);
 	encode_nops(&hdr);
 }
@@ -6972,9 +6973,11 @@ static int nfs4_xdr_dec_delegreturn(struct rpc_rqst *rqstp,
 		if (status)
 			goto out;
 	}
-	status = decode_getfattr(xdr, res->fattr, res->server);
-	if (status != 0)
-		goto out;
+	if (res->fattr) {
+		status = decode_getfattr(xdr, res->fattr, res->server);
+		if (status != 0)
+			goto out;
+	}
 	status = decode_delegreturn(xdr);
 out:
 	return status;