From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751496AbdAMVkD (ORCPT ); Fri, 13 Jan 2017 16:40:03 -0500 Received: from mx4.wp.pl ([212.77.101.12]:51425 "EHLO mx4.wp.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751132AbdAMVkB (ORCPT ); Fri, 13 Jan 2017 16:40:01 -0500 X-Greylist: delayed 399 seconds by postgrey-1.27 at vger.kernel.org; Fri, 13 Jan 2017 16:40:01 EST Date: Fri, 13 Jan 2017 13:32:58 -0800 From: Jakub Kicinski To: Daniel Wagner Cc: "Luis R. Rodriguez" , Bjorn Andersson , linux-kernel@vger.kernel.org Subject: 4.10-rc3, firmware loading via user space helper crashes if firmware not present Message-ID: <20170113133258.1cc6bf39@laptop> X-Mailer: Claws Mail 3.14.0-49-g1cc35f (GTK+ 2.24.31; x86_64-unknown-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-WP-MailID: cc318b77a7848c948c780c28addabbc2 X-WP-AV: skaner antywirusowy Poczty Wirtualnej Polski X-WP-SPAM: NO 000000A [kVOE] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi! If one requests a FW which does not exist in the FS and the user space helper is used then fw_load_abort() will be called twice which leads to NULL-deref. It will be called once in firmware_loading_store() (handling the -1 case) and then again in _request_firmware_load() because return value from fw_state_wait_timeout() was negative. I think this is introduced in by f52cc379423d ("firmware: refactor loading status"). The simple fix would be to not "unlink" the buf by fw_load_abort() in firmware_loading_store() and always rely on firmware_loading_store(). ------->8------------------------------------ diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c index 4497d263209f..89eb9de81145 100644 --- a/drivers/base/firmware_class.c +++ b/drivers/base/firmware_class.c @@ -766,7 +770,7 @@ static ssize_t firmware_loading_store(struct device *dev, dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading); /* fallthrough */ case -1: - fw_load_abort(fw_priv); + fw_state_aborted(&fw_buf->fw_st); break; } out: -------8<------------------------------------ Or should we fix up the ret code handling in __fw_state_wait_common()? Kuba