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 2A000C77B7A for ; Wed, 31 May 2023 13:51:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237331AbjEaNvv (ORCPT ); Wed, 31 May 2023 09:51:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60724 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237097AbjEaNtq (ORCPT ); Wed, 31 May 2023 09:49:46 -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 DAC1C2711; Wed, 31 May 2023 06:45:20 -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 DF19D63B51; Wed, 31 May 2023 13:45:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 56F00C4339C; Wed, 31 May 2023 13:45:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685540706; bh=E2wiyKO3ui/unfMVksv7tVOc4UK7hs8hFdfFF7B69V4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Vhfdgxoji2hIGJFnInV1JZRAYp2yOZWcjffZf3Uqdfgc/EDp+QSmDQEe1e4GqxUpa vkLcVRV96AaZARBeFPREAzJKXkcvQyBFoTxKJZF649uCL7NtR55suzk5FttPk9MOwJ C93OxJSyXyWdRSuXjx78VmwIHkT6/GXs626PWFJqF3vNV/MbtbG8WlSUgvc9fYp1N7 xrFWa8RU1EImpVqJRoyrqH+5FskmKRxd7JtCpTSO9ElXQ96L3FQbGpNSgo4wT0oSNz gqmHYVUftDoqZbwsHMRSLyGCLwXjFSkCB1TVMYsnxTwbUXZExG3LyF0pYwLFgH/ltJ 01gmi3JJf2luA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Hans de Goede , Orson Zhai , Chunyan Zhang , Baolin Wang , Sebastian Reichel , Sasha Levin , sre@kernel.org, linux-pm@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 02/17] power: supply: sc27xx: Fix external_power_changed race Date: Wed, 31 May 2023 09:44:46 -0400 Message-Id: <20230531134502.3384828-2-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230531134502.3384828-1-sashal@kernel.org> References: <20230531134502.3384828-1-sashal@kernel.org> 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 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