From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> stable inclusion from stable-v4.19.319 commit 48542881997e17b49dc16b93fe910e0cfcf7a9f9 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAGEN8 CVE: CVE-2024-41063 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... --------------------------- [ Upstream commit 0d151a103775dd9645c78c97f77d6e2a5298d913 ] syzbot is reporting that calling hci_release_dev() from hci_error_reset() due to hci_dev_put() from hci_error_reset() can cause deadlock at destroy_workqueue(), for hci_error_reset() is called from hdev->req_workqueue which destroy_workqueue() needs to flush. We need to make sure that hdev->{rx_work,cmd_work,tx_work} which are queued into hdev->workqueue and hdev->{power_on,error_reset} which are queued into hdev->req_workqueue are no longer running by the moment destroy_workqueue(hdev->workqueue); destroy_workqueue(hdev->req_workqueue); are called from hci_release_dev(). Call cancel_work_sync() on these work items from hci_unregister_dev() as soon as hdev->list is removed from hci_dev_list. Reported-by: syzbot <syzbot+da0a9c9721e36db712e8@syzkaller.appspotmail.com> Closes: https://syzkaller.appspot.com/bug?extid=da0a9c9721e36db712e8 Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com> --- net/bluetooth/hci_core.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index 74d5169300ff..11bf5aa6e1f9 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -3268,7 +3268,11 @@ void hci_unregister_dev(struct hci_dev *hdev) list_del(&hdev->list); write_unlock(&hci_dev_list_lock); + cancel_work_sync(&hdev->rx_work); + cancel_work_sync(&hdev->cmd_work); + cancel_work_sync(&hdev->tx_work); cancel_work_sync(&hdev->power_on); + cancel_work_sync(&hdev->error_reset); hci_dev_do_close(hdev); -- 2.34.1