From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:50570 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730486AbeKLFsX (ORCPT ); Mon, 12 Nov 2018 00:48:23 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Jonathan Cameron" , "Alison Schofield" , "Ben Hutchings" Date: Sun, 11 Nov 2018 19:49:05 +0000 Message-ID: Subject: [PATCH 3.16 340/366] iio: iio-trig-periodic-rtc: Free trigger resource correctly In-Reply-To: Sender: stable-owner@vger.kernel.org List-ID: 3.16.61-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Ben Hutchings This is based on upstream commit 10e840dfb0b7, which did not touch the iio-trig-periodic-rtc driver because it has been removed upstream. The following explanation comes from that commit: These stand-alone trigger drivers were using iio_trigger_put() where they should have been using iio_trigger_free(). The iio_trigger_put() adds a module_put which is bad since they never did a module_get. In the sysfs driver, module_get/put's are used as triggers are added & removed. This extra module_put() occurs on an error path in the probe routine (probably rare). In the bfin-timer & interrupt trigger drivers, the module resources are not explicitly managed, so it's doing a put on something that was never get'd. It occurs on the probe error path and on the remove path (not so rare). Tested with the sysfs trigger driver. The bfin & interrupt drivers were build tested & inspected only. This was build tested only. Cc: Alison Schofield Cc: Jonathan Cameron Signed-off-by: Ben Hutchings Signed-off-by: Ben Hutchings --- drivers/staging/iio/trigger/iio-trig-periodic-rtc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/staging/iio/trigger/iio-trig-periodic-rtc.c +++ b/drivers/staging/iio/trigger/iio-trig-periodic-rtc.c @@ -123,7 +123,7 @@ static int iio_trig_periodic_rtc_probe(s trig_info = kzalloc(sizeof(*trig_info), GFP_KERNEL); if (!trig_info) { ret = -ENOMEM; - goto error_put_trigger_and_remove_from_list; + goto error_free_trigger_and_remove_from_list; } iio_trigger_set_drvdata(trig, trig_info); trig->ops = &iio_prtc_trigger_ops; @@ -151,9 +151,9 @@ error_close_rtc: rtc_class_close(trig_info->rtc); error_free_trig_info: kfree(trig_info); -error_put_trigger_and_remove_from_list: +error_free_trigger_and_remove_from_list: list_del(&trig->alloc_list); - iio_trigger_put(trig); + iio_trigger_free(trig); error_free_completed_registrations: list_for_each_entry_safe(trig, trig2,