From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 58D35C7EE2E for ; Wed, 31 May 2023 13:48:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236622AbjEaNsy (ORCPT ); Wed, 31 May 2023 09:48:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60288 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236836AbjEaNsV (ORCPT ); Wed, 31 May 2023 09:48:21 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DB9172686; Wed, 31 May 2023 06:44:35 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C6C5863B1B; Wed, 31 May 2023 13:43:23 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 52221C433D2; Wed, 31 May 2023 13:43:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685540603; bh=ll0vE8kIeS0vOprbv+35WOxuWa6YWtWpGEHFAHrLAfk=; h=From:To:Cc:Subject:Date:From; b=N8Qmne9wdYwZzjKAc4HbmvdKaGhhnSpNUrRNy0MoGf9wcOPeUGjE31fqaL79Q7ugK 8pbhyFfBInKD4iKOKRzO8wdSHXKHfnTOc7Wo2cxQVARSPYa4HPfJ343M+8jF30DR/E yeUsn3y8iRVDFPU3Z/BtzM0t4Bjf0+cWrG+RGem4BRk6Ruv1FFZ8AWd8QcpyEcw3DV +rS0Ia6K03+cE/2ZrQJOOt81a0qgduJR+Q2RhRbWKl0Lj0Tatjgs7+qrC1UdyUfBmt 2AaIotpoV47INGdhMYCwVBCalNik2KSBlp7YjjA43pm0EKRNu54NqCAt4lUMilIYBk 5GoY86TCKnb+g== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Hans de Goede , Linus Walleij , Sebastian Reichel , Sasha Levin , sre@kernel.org, linux-pm@vger.kernel.org Subject: [PATCH AUTOSEL 5.15 01/24] power: supply: ab8500: Fix external_power_changed race Date: Wed, 31 May 2023 09:42:57 -0400 Message-Id: <20230531134320.3384102-1-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Hans de Goede [ Upstream commit a5299ce4e96f3e8930e9c051b28d8093ada87b08 ] ab8500_btemp_external_power_changed() dereferences di->btemp_psy, which gets sets in ab8500_btemp_probe() like this: di->btemp_psy = devm_power_supply_register(dev, &ab8500_btemp_desc, &psy_cfg); As soon as devm_power_supply_register() has called device_add() the external_power_changed callback can get called. So there is a window where ab8500_btemp_external_power_changed() may get called while di->btemp_psy has not been set yet leading to a NULL pointer dereference. Fixing this is easy. The external_power_changed callback gets passed the power_supply which will eventually get stored in di->btemp_psy, so ab8500_btemp_external_power_changed() can simply directly use the passed in psy argument which is always valid. And the same applies to ab8500_fg_external_power_changed(). Signed-off-by: Hans de Goede Reviewed-by: Linus Walleij Signed-off-by: Sebastian Reichel Signed-off-by: Sasha Levin --- drivers/power/supply/ab8500_btemp.c | 6 ++---- drivers/power/supply/ab8500_fg.c | 6 ++---- 2 files changed, 4 insertions(+), 8 deletions(-) diff --git a/drivers/power/supply/ab8500_btemp.c b/drivers/power/supply/ab8500_btemp.c index b6c9111d77d7d..896309d3cadfe 100644 --- a/drivers/power/supply/ab8500_btemp.c +++ b/drivers/power/supply/ab8500_btemp.c @@ -902,10 +902,8 @@ static int ab8500_btemp_get_ext_psy_data(struct device *dev, void *data) */ static void ab8500_btemp_external_power_changed(struct power_supply *psy) { - struct ab8500_btemp *di = power_supply_get_drvdata(psy); - - class_for_each_device(power_supply_class, NULL, - di->btemp_psy, ab8500_btemp_get_ext_psy_data); + class_for_each_device(power_supply_class, NULL, psy, + ab8500_btemp_get_ext_psy_data); } /* ab8500 btemp driver interrupts and their respective isr */ diff --git a/drivers/power/supply/ab8500_fg.c b/drivers/power/supply/ab8500_fg.c index 57799a8079d44..eb7eac23da70f 100644 --- a/drivers/power/supply/ab8500_fg.c +++ b/drivers/power/supply/ab8500_fg.c @@ -2384,10 +2384,8 @@ static int ab8500_fg_init_hw_registers(struct ab8500_fg *di) */ static void ab8500_fg_external_power_changed(struct power_supply *psy) { - struct ab8500_fg *di = power_supply_get_drvdata(psy); - - class_for_each_device(power_supply_class, NULL, - di->fg_psy, ab8500_fg_get_ext_psy_data); + class_for_each_device(power_supply_class, NULL, psy, + ab8500_fg_get_ext_psy_data); } /** -- 2.39.2