Patch "Revert "NFSv4: Remove incorrect check in can_open_delegated()"" has been added to the 4.2-stable tree

Patch "Revert "NFSv4: Remove incorrect check in can_open_delegated()"" has been added to the 4.2-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

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

to the 4.2-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     revert-nfsv4-remove-incorrect-check-in-can_open_delegated.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 36319608e28701c07cad80ae3be8b0fdfb1ab40f Mon Sep 17 00:00:00 2001
From: Trond Myklebust <trond.myklebust@primarydata.com>
Date: Wed, 19 Aug 2015 00:14:20 -0500
Subject: Revert "NFSv4: Remove incorrect check in can_open_delegated()"

From: Trond Myklebust <trond.myklebust@primarydata.com>

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>

---
 fs/nfs/nfs4proc.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1156,6 +1156,8 @@ static int can_open_delegated(struct nfs
 		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);


Patches currently in stable-queue which might be from trond.myklebust@primarydata.com are

queue-4.2/nfs41-flexfiles-zero-out-ds-write-wcc.patch
queue-4.2/nfs-nfs_set_pgio_error-sometimes-misses-errors.patch
queue-4.2/nfs-fix-a-null-pointer-dereference-of-migration-recovery-ops-for-v4.2-client.patch
queue-4.2/sunrpc-xs_reset_transport-must-mark-the-connection-as-disconnected.patch
queue-4.2/nfs-fix-truncated-client-owner-id-without-proto-type.patch
queue-4.2/nfs-don-t-let-the-ctime-override-attribute-barriers.patch
queue-4.2/sunrpc-fix-a-thinko-in-xs_connect.patch
queue-4.2/nfsv4-don-t-set-setattr-for-o_rdonly-o_excl.patch
queue-4.2/nfs41-flexfiles-update-inode-after-write-finishes.patch
queue-4.2/nfsv4.1-pnfs-fix-borken-function-_same_data_server_addrs_locked.patch
queue-4.2/nfsv4-force-a-post-op-attribute-update-when-holding-a-delegation.patch
queue-4.2/nfsv4.1-pnfs-fix-atomicity-of-commit-list-updates.patch
queue-4.2/nfsv4.1-flexfiles-fix-a-protocol-error-in-layoutreturn.patch
queue-4.2/revert-nfsv4-remove-incorrect-check-in-can_open_delegated.patch
queue-4.2/nfsv4.1-fix-a-protocol-issue-with-close-stateids.patch