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 41D9DC77B7C for ; Sun, 28 May 2023 19:35:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230344AbjE1TfQ (ORCPT ); Sun, 28 May 2023 15:35:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51148 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230357AbjE1TfO (ORCPT ); Sun, 28 May 2023 15:35:14 -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 A6222DC for ; Sun, 28 May 2023 12:34:57 -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 4B5AC61DF0 for ; Sun, 28 May 2023 19:34:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6847BC4339B; Sun, 28 May 2023 19:34:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1685302494; bh=MwTGrKYNPdamWbkxpMIn3/Lp1x50/ZzFv/NxFcV55yU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AvwS+Du69iKvyAt/w85iDT47ceQhUgUyagk+CpYsEIi0AZplY+p8krxQSugiEkJWw hA8WtK3iEACqPcd2J9v2mHVHMZy7Ll2oVhy9PHzQ4xeAYRMnlBpKgDlpsB8v2BrxCN QIgwfWwzu3fk6GGZI9t2mXnMx2vwrDZNPTCZjwos= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Marek Vasut , Hans de Goede , Sebastian Reichel Subject: [PATCH 6.1 026/119] power: supply: bq25890: Fix external_power_changed race Date: Sun, 28 May 2023 20:10:26 +0100 Message-Id: <20230528190836.211187629@linuxfoundation.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230528190835.386670951@linuxfoundation.org> References: <20230528190835.386670951@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 commit 029a443b9b6424170f00f6dd5b7682e682cce92e upstream. bq25890_charger_external_power_changed() dereferences bq->charger, which gets sets in bq25890_power_supply_init() like this: bq->charger = devm_power_supply_register(bq->dev, &bq->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 bq25890_charger_external_power_changed() may get called while bq->charger has not been set yet leading to a NULL pointer dereference. This race hits during boot sometimes on a Lenovo Yoga Book 1 yb1-x90f when the cht_wcove_pwrsrc (extcon) power_supply is done with detecting the connected charger-type which happens to exactly hit the small window: BUG: kernel NULL pointer dereference, address: 0000000000000018 RIP: 0010:__power_supply_is_supplied_by+0xb/0xb0 Call Trace: __power_supply_get_supplier_property+0x19/0x50 class_for_each_device+0xb1/0xe0 power_supply_get_property_from_supplier+0x2e/0x50 bq25890_charger_external_power_changed+0x38/0x1b0 [bq25890_charger] __power_supply_changed_work+0x30/0x40 class_for_each_device+0xb1/0xe0 power_supply_changed_work+0x5f/0xe0 Fixing this is easy. The external_power_changed callback gets passed the power_supply which will eventually get stored in bq->charger, so bq25890_charger_external_power_changed() can simply directly use the passed in psy argument which is always valid. Fixes: eab25b4f93aa ("power: supply: bq25890: On the bq25892 set the IINLIM based on external charger detection") Cc: stable@vger.kernel.org Cc: Marek Vasut Signed-off-by: Hans de Goede Signed-off-by: Sebastian Reichel Signed-off-by: Greg Kroah-Hartman --- drivers/power/supply/bq25890_charger.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/power/supply/bq25890_charger.c +++ b/drivers/power/supply/bq25890_charger.c @@ -650,7 +650,7 @@ static void bq25890_charger_external_pow if (bq->chip_version != BQ25892) return; - ret = power_supply_get_property_from_supplier(bq->charger, + ret = power_supply_get_property_from_supplier(psy, POWER_SUPPLY_PROP_USB_TYPE, &val); if (ret)