From 6cd9ecd59521d89c087c561680ae272dcc3a5059 Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@redhat.com>
Date: Tue, 28 Jan 2014 16:01:04 -0500
Subject: [PATCH] nfsd4: session needs room for following op to error out

commit 4c69d5855a16f7378648c5733632628fa10431db upstream.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 fs/nfsd/nfs4proc.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 82189b208af3..b9048e5e349e 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1359,6 +1359,12 @@ nfsd4_proc_compound(struct svc_rqst *rqstp,
 		/* If op is non-idempotent */
 		if (opdesc->op_flags & OP_MODIFIES_SOMETHING) {
 			plen = opdesc->op_rsize_bop(rqstp, op);
+			/*
+			 * If there's still another operation, make sure
+			 * we'll have space to at least encode an error:
+			 */
+			if (resp->opcnt < args->opcnt)
+				plen += COMPOUND_ERR_SLACK_SPACE;
 			op->status = nfsd4_check_resp_size(resp, plen);
 		}