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, syzbot+70ce058e01259de7bb1d@syzkaller.appspotmail.com, Benjamin Beichler , Johannes Berg Subject: [PATCH 4.14 183/183] mac80211_hwsim: fix use-after-free bug in hwsim_exit_net Date: Wed, 25 Apr 2018 12:36:43 +0200 Message-Id: <20180425103249.853994921@linuxfoundation.org> In-Reply-To: <20180425103242.532713678@linuxfoundation.org> References: <20180425103242.532713678@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Benjamin Beichler commit 8cfd36a0b53aeb4ec21d81eb79706697b84dfc3d upstream. When destroying a net namespace, all hwsim interfaces, which are not created in default namespace are deleted. But the async deletion of the interfaces could last longer than the actual destruction of the namespace, which results to an use after free bug. Therefore use synchronous deletion in this case. Fixes: 100cb9ff40e0 ("mac80211_hwsim: Allow managing radios from non-initial namespaces") Reported-by: syzbot+70ce058e01259de7bb1d@syzkaller.appspotmail.com Signed-off-by: Benjamin Beichler Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/mac80211_hwsim.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/net/wireless/mac80211_hwsim.c +++ b/drivers/net/wireless/mac80211_hwsim.c @@ -3427,8 +3427,11 @@ static void __net_exit hwsim_exit_net(st continue; list_del(&data->list); - INIT_WORK(&data->destroy_work, destroy_radio); - schedule_work(&data->destroy_work); + spin_unlock_bh(&hwsim_radio_lock); + mac80211_hwsim_del_radio(data, wiphy_name(data->hw->wiphy), + NULL); + spin_lock_bh(&hwsim_radio_lock); + } spin_unlock_bh(&hwsim_radio_lock); }