From patchwork Tue Sep 29 10:56:26 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 290900 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 30075C4727C for ; Tue, 29 Sep 2020 12:15:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D48492075A for ; Tue, 29 Sep 2020 12:15:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601381740; bh=JABLUdjNq2imK1wjeCunrhCzek4I+Lgbd0ewlVoivLU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Y/K7f25EFAJ+LmR3+qPsPMqFvRrpgXkf2KFIIOxArPYjKkQsZUCcrvQga68aMYffZ T6Lsy8O63pebk440g61xCuCe5zR8VHBn1ulXVBXRu9Zb93y96z21Tqi3Kyhpm9EpcA bycEe7IfgtBRiU9AeegLTD42h1qf0yGqw+zXMY9E= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732210AbgI2MPP (ORCPT ); Tue, 29 Sep 2020 08:15:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:56994 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730092AbgI2Lh2 (ORCPT ); Tue, 29 Sep 2020 07:37:28 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 662E7208FE; Tue, 29 Sep 2020 11:33:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601379212; bh=JABLUdjNq2imK1wjeCunrhCzek4I+Lgbd0ewlVoivLU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fMJFca/r44/SGlcGLi63z/n8WaSiyKj9a1Mc53hRb72ivJ+d/Fgezz9FX/9lR2V5Z 4TBWKlidpZp7u/GDPm0WTKm0ugdj7eseQ77IbFmG2m0TS69lfPUcoW1SqVv7PT6PQX Iys5DF1vj9O03mgGwq9eUTvac3J3KB3unxrL/ao4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Felix Fietkau , Sasha Levin Subject: [PATCH 5.4 055/388] mt76: do not use devm API for led classdev Date: Tue, 29 Sep 2020 12:56:26 +0200 Message-Id: <20200929110013.158835994@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200929110010.467764689@linuxfoundation.org> References: <20200929110010.467764689@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Felix Fietkau [ Upstream commit 36f7e2b2bb1de86f0072cd49ca93d82b9e8fd894 ] With the devm API, the unregister happens after the device cleanup is done, after which the struct mt76_dev which contains the led_cdev has already been freed. This leads to a use-after-free bug that can crash the system. Signed-off-by: Felix Fietkau Signed-off-by: Sasha Levin --- drivers/net/wireless/mediatek/mt76/mac80211.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/mediatek/mt76/mac80211.c b/drivers/net/wireless/mediatek/mt76/mac80211.c index 1a2c143b34d01..7be5806a1c398 100644 --- a/drivers/net/wireless/mediatek/mt76/mac80211.c +++ b/drivers/net/wireless/mediatek/mt76/mac80211.c @@ -105,7 +105,15 @@ static int mt76_led_init(struct mt76_dev *dev) dev->led_al = of_property_read_bool(np, "led-active-low"); } - return devm_led_classdev_register(dev->dev, &dev->led_cdev); + return led_classdev_register(dev->dev, &dev->led_cdev); +} + +static void mt76_led_cleanup(struct mt76_dev *dev) +{ + if (!dev->led_cdev.brightness_set && !dev->led_cdev.blink_set) + return; + + led_classdev_unregister(&dev->led_cdev); } static void mt76_init_stream_cap(struct mt76_dev *dev, @@ -360,6 +368,7 @@ void mt76_unregister_device(struct mt76_dev *dev) { struct ieee80211_hw *hw = dev->hw; + mt76_led_cleanup(dev); mt76_tx_status_check(dev, NULL, true); ieee80211_unregister_hw(hw); }