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 1C43AEB64D9 for ; Mon, 19 Jun 2023 10:52:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232267AbjFSKwt (ORCPT ); Mon, 19 Jun 2023 06:52:49 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53146 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230375AbjFSKwX (ORCPT ); Mon, 19 Jun 2023 06:52:23 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4EA9210CE for ; Mon, 19 Jun 2023 03:51:24 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 1CC6960B85 for ; Mon, 19 Jun 2023 10:51:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 30A89C433C0; Mon, 19 Jun 2023 10:51:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1687171883; bh=E2wiyKO3ui/unfMVksv7tVOc4UK7hs8hFdfFF7B69V4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=npJqv+6nFJ3C6OLBX/DGhFmiERRU50FIw9ZGnh3YaxnqsUaUt/W/XoICoYtJOrmH9 dqvbADeqixW14SR6PXygS4ntiz/b2OyQJ96edr+/Sam4BSwis7xs4Z+DQHLqTO1X79 lH9CMTFCjA0BerhvzdjCkgL2YnKIuTBPbW1WHokE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Orson Zhai , Chunyan Zhang , Hans de Goede , Baolin Wang , Sebastian Reichel , Sasha Levin Subject: [PATCH 5.4 06/64] power: supply: sc27xx: Fix external_power_changed race Date: Mon, 19 Jun 2023 12:30:02 +0200 Message-ID: <20230619102133.146653600@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230619102132.808972458@linuxfoundation.org> References: <20230619102132.808972458@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Hans de Goede [ Upstream commit 4d5c129d6c8993fe96e9ae712141eedcb9ca68c2 ] sc27xx_fgu_external_power_changed() dereferences data->battery, which gets sets in ab8500_btemp_probe() like this: data->battery = devm_power_supply_register(dev, &sc27xx_fgu_desc, &fgu_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 sc27xx_fgu_external_power_changed() may get called while data->battery 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 data->battery, so sc27xx_fgu_external_power_changed() can simply directly use the passed in psy argument which is always valid. After this change sc27xx_fgu_external_power_changed() is reduced to just "power_supply_changed(psy);" and it has the same prototype. While at it simply replace it with making the external_power_changed callback directly point to power_supply_changed. Cc: Orson Zhai Cc: Chunyan Zhang Signed-off-by: Hans de Goede Reviewed-by: Baolin Wang Signed-off-by: Sebastian Reichel Signed-off-by: Sasha Levin --- drivers/power/supply/sc27xx_fuel_gauge.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c b/drivers/power/supply/sc27xx_fuel_gauge.c index 5e5bcdbf2e695..557b02d408134 100644 --- a/drivers/power/supply/sc27xx_fuel_gauge.c +++ b/drivers/power/supply/sc27xx_fuel_gauge.c @@ -634,13 +634,6 @@ static int sc27xx_fgu_set_property(struct power_supply *psy, return ret; } -static void sc27xx_fgu_external_power_changed(struct power_supply *psy) -{ - struct sc27xx_fgu_data *data = power_supply_get_drvdata(psy); - - power_supply_changed(data->battery); -} - static int sc27xx_fgu_property_is_writeable(struct power_supply *psy, enum power_supply_property psp) { @@ -671,7 +664,7 @@ static const struct power_supply_desc sc27xx_fgu_desc = { .num_properties = ARRAY_SIZE(sc27xx_fgu_props), .get_property = sc27xx_fgu_get_property, .set_property = sc27xx_fgu_set_property, - .external_power_changed = sc27xx_fgu_external_power_changed, + .external_power_changed = power_supply_changed, .property_is_writeable = sc27xx_fgu_property_is_writeable, }; -- 2.39.2