From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pl0-f65.google.com ([209.85.160.65]:41673 "EHLO mail-pl0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751189AbeCGRQS (ORCPT ); Wed, 7 Mar 2018 12:16:18 -0500 Subject: Re: [PATCH] ssb:: use put_device() if device_register fail To: =?UTF-8?Q?Michael_B=c3=bcsch?= References: <20180307174700.013e20ae@wiggum> Cc: linux-kernel@vger.kernel.org, linux-wireless@vger.kernel.org From: arvindY Message-ID: <5AA01E5E.8070002@gmail.com> (sfid-20180307_181637_170240_39A19BA1) Date: Wed, 7 Mar 2018 22:46:14 +0530 MIME-Version: 1.0 In-Reply-To: <20180307174700.013e20ae@wiggum> Content-Type: text/plain; charset=windows-1252; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wednesday 07 March 2018 10:17 PM, Michael Büsch wrote: > On Wed, 7 Mar 2018 15:31:30 +0530 > Arvind Yadav wrote: > >> if device_register() returned an error! Always use put_device() >> to give up the reference initialized. >> >> Signed-off-by: Arvind Yadav >> --- >> drivers/ssb/main.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/drivers/ssb/main.c b/drivers/ssb/main.c >> index 65420a9..c4449e0 100644 >> --- a/drivers/ssb/main.c >> +++ b/drivers/ssb/main.c >> @@ -521,6 +521,7 @@ static int ssb_devices_register(struct ssb_bus *bus) >> ssb_err("Could not register %s\n", dev_name(dev)); >> /* Set dev to NULL to not unregister >> * dev on error unwinding. */ >> + put_device(dev); >> sdev->dev = NULL; >> kfree(devwrap); >> goto error; > > I don't think this is correct. > The dev structure is allocated as part of devwrap, which is freed here. > > Why do you think we need put_device here? > Yes this patch is not correct, We must not use kfree() after you called device_register() (even if it was not successful!) -- see the comment for device_register(). I will delete kfree() and send updated patch. ~arvind