From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leo Yan Subject: Re: [PATCH] ARM: cpuidle: Avoid memleak if init fail Date: Fri, 1 Sep 2017 09:33:17 +0800 Message-ID: <20170901013317.GA516@leoy-ThinkPad-T440> References: <1504211076-2331-1-git-send-email-stefan.wahren@i2se.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pf0-f178.google.com ([209.85.192.178]:33533 "EHLO mail-pf0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750955AbdIABdZ (ORCPT ); Thu, 31 Aug 2017 21:33:25 -0400 Received: by mail-pf0-f178.google.com with SMTP id n73so3852937pfj.0 for ; Thu, 31 Aug 2017 18:33:25 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1504211076-2331-1-git-send-email-stefan.wahren@i2se.com> Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: Stefan Wahren Cc: Daniel Lezcano , "Rafael J . Wysocki" , Sudeep Holla , linux-pm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Hi Stefan, On Thu, Aug 31, 2017 at 10:24:36PM +0200, Stefan Wahren wrote: > In case there are no DT idle states defined or > cpuidle_register_driver() fails, the copy of the idle driver is leaked: > > unreferenced object 0xede0dc00 (size 1024): > comm "swapper/0", pid 1, jiffies 4294937431 (age 744.510s) > hex dump (first 32 bytes): > 94 9e 0b c1 00 00 00 00 00 00 00 00 00 00 00 00 ................ > 57 46 49 00 00 00 00 00 00 00 00 00 00 00 00 00 WFI............. > backtrace: > [] arm_idle_init+0x44/0x1ac > [] do_one_initcall+0x3c/0x16c > [] kernel_init_freeable+0x110/0x1d0 > [] kernel_init+0x8/0x114 > [] ret_from_fork+0x14/0x3c > > So fix this by freeing the unregistered copy in error case. > > Signed-off-by: Stefan Wahren > Fixes: d50a7d8acd78 ("ARM: cpuidle: Support asymmetric idle definition") > --- > drivers/cpuidle/cpuidle-arm.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/cpuidle/cpuidle-arm.c b/drivers/cpuidle/cpuidle-arm.c > index 7080c38..52a7505 100644 > --- a/drivers/cpuidle/cpuidle-arm.c > +++ b/drivers/cpuidle/cpuidle-arm.c > @@ -104,13 +104,13 @@ static int __init arm_idle_init(void) > ret = dt_init_idle_driver(drv, arm_idle_state_match, 1); > if (ret <= 0) { > ret = ret ? : -ENODEV; > - goto out_fail; > + goto init_fail; > } > > ret = cpuidle_register_driver(drv); > if (ret) { > pr_err("Failed to register cpuidle driver\n"); > - goto out_fail; > + goto init_fail; > } > > /* > @@ -149,6 +149,8 @@ static int __init arm_idle_init(void) > } > > return 0; > +init_fail: > + kfree(drv); The below loop only releases resource for previous CPUs, so should check two variables 'drv' and 'dev'. If 'dev != NULL', we also need to release it. Thanks, Leo Yan > out_fail: > while (--cpu >= 0) { > dev = per_cpu(cpuidle_devices, cpu); > -- > 2.7.4 >