From 3a2b19d1ee5633f76ae8a88da7bc039a5d1732aa Mon Sep 17 00:00:00 2001 From: Vasily Averin Date: Thu, 2 Nov 2017 13:03:42 +0300 Subject: [PATCH] lockd: lost rollback of set_grace_period() in lockd_down_net() Commit efda760fe95ea ("lockd: fix lockd shutdown race") is incorrect, it removes lockd_manager and disarm grace_period_end for init_net only. If nfsd was started from another net namespace lockd_up_net() calls set_grace_period() that adds lockd_manager into per-netns list and queues grace_period_end delayed work. These action should be reverted in lockd_down_net(). Otherwise it can lead to double list_add on after restart nfsd in netns, and to use-after-free if non-disarmed delayed work will be executed after netns destroy. Fixes: efda760fe95e ("lockd: fix lockd shutdown race") Cc: stable@vger.kernel.org Signed-off-by: Vasily Averin Signed-off-by: J. Bruce Fields --- fs/lockd/svc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/lockd/svc.c b/fs/lockd/svc.c index cb659ef789c0..4acf0ebd9802 100644 --- a/fs/lockd/svc.c +++ b/fs/lockd/svc.c @@ -274,6 +274,8 @@ static void lockd_down_net(struct svc_serv *serv, struct net *net) if (ln->nlmsvc_users) { if (--ln->nlmsvc_users == 0) { nlm_shutdown_hosts_net(net); + cancel_delayed_work_sync(&ln->grace_period_end); + locks_end_grace(&ln->lockd_manager); svc_shutdown_net(serv, net); dprintk("%s: per-net data destroyed; net=%x\n", __func__, net->ns.inum); -- 2.30.2