linux-kernel - [PATCH 5.4 08/72] NFSv4.1 handle ERR_DELAY error reclaiming locking state on delegation recall

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200921163122.276933879@linuxfoundation.org>
Date:   Mon, 21 Sep 2020 18:30:47 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Olga Kornievskaia <kolga@...app.com>,
        Trond Myklebust <trond.myklebust@...merspace.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.4 08/72] NFSv4.1 handle ERR_DELAY error reclaiming locking state on delegation recall

From: Olga Kornievskaia <kolga@...app.com>

[ Upstream commit 3d7a9520f0c3e6a68b6de8c5812fc8b6d7a52626 ]

A client should be able to handle getting an ERR_DELAY error
while doing a LOCK call to reclaim state due to delegation being
recalled. This is a transient error that can happen due to server
moving its volumes and invalidating its file location cache and
upon reference to it during the LOCK call needing to do an
expensive lookup (leading to an ERR_DELAY error on a PUTFH).

Signed-off-by: Olga Kornievskaia <kolga@...app.com>
Signed-off-by: Trond Myklebust <trond.myklebust@...merspace.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 fs/nfs/nfs4proc.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index d0cb827b72cfa..16414ae02c089 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -7232,7 +7232,12 @@ int nfs4_lock_delegation_recall(struct file_lock *fl, struct nfs4_state *state,
 	err = nfs4_set_lock_state(state, fl);
 	if (err != 0)
 		return err;
-	err = _nfs4_do_setlk(state, F_SETLK, fl, NFS_LOCK_NEW);
+	do {
+		err = _nfs4_do_setlk(state, F_SETLK, fl, NFS_LOCK_NEW);
+		if (err != -NFS4ERR_DELAY)
+			break;
+		ssleep(1);
+	} while (err == -NFS4ERR_DELAY);
 	return nfs4_handle_delegation_recall_error(server, state, stateid, fl, err);
 }
 
-- 
2.25.1