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 4b66b0c469cd18bc1a7f1e74bce47794b223e695..6dcbc5defb7a8dd670b63995eb553c379e47a0d4 100644 (file)
--- 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 6f2365b99fb441959ac856e10a01ba2414abcdcd..e9255cb453e664c385c9a94969f69bc3514024b1 100644 (file)
--- 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;