From: Trond Myklebust <trond.myklebust@primarydata.com>
Date: Wed, 19 Aug 2015 05:14:20 +0000 (-0500)
Subject: Revert "NFSv4: Remove incorrect check in can_open_delegated()"
X-Git-Tag: v4.1.9~94
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=d40d9de9d3533ef6607342ec153b426b9d2b892e;p=users%2Fjedix%2Flinux-maple.git

Revert "NFSv4: Remove incorrect check in can_open_delegated()"

commit 36319608e28701c07cad80ae3be8b0fdfb1ab40f upstream.

This reverts commit 4e379d36c050b0117b5d10048be63a44f5036115.

This commit opens up a race between the recovery code and the open code.

Reported-by: Olga Kornievskaia <aglo@umich.edu>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index d69bd6ae0ff0..c245874d7e9d 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1152,6 +1152,8 @@ static int can_open_delegated(struct nfs_delegation *delegation, fmode_t fmode)
 		return 0;
 	if ((delegation->type & fmode) != fmode)
 		return 0;
+	if (test_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags))
+		return 0;
 	if (test_bit(NFS_DELEGATION_RETURNING, &delegation->flags))
 		return 0;
 	nfs_mark_delegation_referenced(delegation);