Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755430AbbDIIz4 (ORCPT ); Thu, 9 Apr 2015 04:55:56 -0400 Received: from mail.kernel.org ([198.145.29.136]:42893 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755406AbbDIIzr (ORCPT ); Thu, 9 Apr 2015 04:55:47 -0400 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Ashay Jaiswal , Mark Brown , Zefan Li Subject: [PATCH 3.4 118/176] regulator: core: fix race condition in regulator_put() Date: Thu, 9 Apr 2015 16:46:06 +0800 Message-Id: <1428569224-23820-118-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1428569028-23762-1-git-send-email-lizf@kernel.org> References: <1428569028-23762-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1908 Lines: 58 From: Ashay Jaiswal 3.4.107-rc1 review patch. If anyone has any objections, please let me know. ------------------ commit 83b0302d347a49f951e904184afe57ac3723476e upstream. The regulator framework maintains a list of consumer regulators for a regulator device and protects it from concurrent access using the regulator device's mutex lock. In the case of regulator_put() the consumer is removed and regulator device's parameters are updated without holding the regulator device's mutex. This would lead to a race condition between the regulator_put() and any function which traverses the consumer list or modifies regulator device's parameters. Fix this race condition by holding the regulator device's mutex in case of regulator_put. Signed-off-by: Ashay Jaiswal Signed-off-by: Mark Brown [lizf: Backported to 3.4: - adjust context - no need to change the comment] Signed-off-by: Zefan Li --- drivers/regulator/core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index c18f0fd..0d71557 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1395,12 +1395,14 @@ void regulator_put(struct regulator *regulator) device_remove_file(regulator->dev, ®ulator->dev_attr); kfree(regulator->dev_attr.attr.name); } + mutex_lock(&rdev->mutex); kfree(regulator->supply_name); list_del(®ulator->list); kfree(regulator); rdev->open_count--; rdev->exclusive = 0; + mutex_unlock(&rdev->mutex); module_put(rdev->owner); mutex_unlock(®ulator_list_mutex); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/