From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Al Viro Subject: [PATCH 3.14 078/114] get rid of propagate_umount() mistakenly treating slaves as busy. Date: Mon, 15 Sep 2014 12:26:18 -0700 Message-Id: <20140915192643.878691715@linuxfoundation.org> In-Reply-To: <20140915192641.428509513@linuxfoundation.org> References: <20140915192641.428509513@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Al Viro commit 88b368f27a094277143d8ecd5a056116f6a41520 upstream. The check in __propagate_umount() ("has somebody explicitly mounted something on that slave?") is done *before* taking the already doomed victims out of the child lists. Signed-off-by: Al Viro Signed-off-by: Greg Kroah-Hartman --- fs/namespace.c | 4 +++- fs/pnode.c | 1 + 2 files changed, 4 insertions(+), 1 deletion(-) --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1253,6 +1253,9 @@ void umount_tree(struct mount *mnt, int hlist_add_head(&p->mnt_hash, &tmp_list); } + hlist_for_each_entry(p, &tmp_list, mnt_hash) + list_del_init(&p->mnt_child); + if (how) propagate_umount(&tmp_list); @@ -1263,7 +1266,6 @@ void umount_tree(struct mount *mnt, int p->mnt_ns = NULL; if (how < 2) p->mnt.mnt_flags |= MNT_SYNC_UMOUNT; - list_del_init(&p->mnt_child); if (mnt_has_parent(p)) { put_mountpoint(p->mnt_mp); /* move the reference to mountpoint into ->mnt_ex_mountpoint */ --- a/fs/pnode.c +++ b/fs/pnode.c @@ -381,6 +381,7 @@ static void __propagate_umount(struct mo * other children */ if (child && list_empty(&child->mnt_mounts)) { + list_del_init(&child->mnt_child); hlist_del_init_rcu(&child->mnt_hash); hlist_add_before_rcu(&child->mnt_hash, &mnt->mnt_hash); }