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: v4.2.2~46
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cb54eac659b31fc9811d0e6cb50f11cb6db34a14;p=thirdparty%2Fkernel%2Fstable.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 6d134e8c2f0d5..73c8204ad4634 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1156,6 +1156,8 @@ 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);