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 B9D52C77B7A for ; Wed, 31 May 2023 13:52:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237217AbjEaNw4 (ORCPT ); Wed, 31 May 2023 09:52:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60308 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237307AbjEaNuV (ORCPT ); Wed, 31 May 2023 09:50:21 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1DE9E1BF2; Wed, 31 May 2023 06:45:50 -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 86B3863B94; Wed, 31 May 2023 13:45:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 30360C433D2; Wed, 31 May 2023 13:45:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685540744; bh=2JLfz6tfQEPJb7CnVemWAmMS6q+Kz6PN2Zzsfl1N9Jc=; h=From:To:Cc:Subject:Date:From; b=cxX1S7ygL+wsnSq/yTRLwqmhyUhGKis9lse7fFE4zj4BB2PoNFJfmB1fGKRSAub8C PwtOA/ae/cIMwhINjyCyccGNlBpWxOqI3NxLaZYaUROrTlBE9g236rSomj7I8343vS 2I143XLzWq9sDrHVGj1OSGeC/FTHQntb/6jBbRQUwG3q8QpnS+p5jAvMQIvBsKKsV7 QzOsGfXkMt3CNU6+OnGF/mwHHkkuGtiid2tPYlodaDABoGZhapR/MwSa4fFSzpIw8L 4iNOTul502VUaDvlmyHrbPftEnO2RHoG6r4qDaVzUqmj0PZZ7/X+Zge8Ljan5yveaf IX3pfqb8wmAsw== 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 4.19 01/13] power: supply: ab8500: Fix external_power_changed race Date: Wed, 31 May 2023 09:45:29 -0400 Message-Id: <20230531134541.3385043-1-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 0fd24577112eb..0bec8b90667c8 100644 --- a/drivers/power/supply/ab8500_btemp.c +++ b/drivers/power/supply/ab8500_btemp.c @@ -919,10 +919,8 @@ 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 675f9d0e8471e..d0cbd7189a622 100644 --- a/drivers/power/supply/ab8500_fg.c +++ b/drivers/power/supply/ab8500_fg.c @@ -2380,10 +2380,8 @@ 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