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 X-Spam-Level: X-Spam-Status: No, score=-9.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 54FB2C4360C for ; Sun, 29 Sep 2019 20:11:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 25A0520863 for ; Sun, 29 Sep 2019 20:11:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=nbd.name header.i=@nbd.name header.b="K/erp3TO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729091AbfI2ULo (ORCPT ); Sun, 29 Sep 2019 16:11:44 -0400 Received: from nbd.name ([46.4.11.11]:49644 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725948AbfI2ULo (ORCPT ); Sun, 29 Sep 2019 16:11:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=nbd.name; s=20160729; h=Message-Id:Date:Subject:To:From:Sender:Reply-To:Cc: MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:In-Reply-To:References:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=pRTz2pw7iVLqX/8lNfiUebhUQuDRc/3/8pZtCCj4+f4=; b=K/erp3TOTxT48cQoFHr9qzV2za O437uTVS5HNTcbhaJah4yxW5YJVtjn8yhmKDa4ZtN3fFJbi6tqk1WFAA/YaDoIQr/2/Dwv7ga+MTO AkMuqXETvKazZgu4i29T9AooH9yI6gSB9a4MIpRPKzk+5LJDM2Ay8Yrl5xCy6bUN7szQ=; Received: from p5b20652d.dip0.t-ipconnect.de ([91.32.101.45] helo=maeck.local) by ds12 with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1iEfXi-000420-T4 for linux-wireless@vger.kernel.org; Sun, 29 Sep 2019 22:11:42 +0200 Received: by maeck.local (Postfix, from userid 501) id 1B0936A0074B; Sun, 29 Sep 2019 22:11:41 +0200 (CEST) From: Felix Fietkau To: linux-wireless@vger.kernel.org Subject: [PATCH] mt76: do not use devm API for led classdev Date: Sun, 29 Sep 2019 22:11:41 +0200 Message-Id: <20190929201141.50613-1-nbd@nbd.name> X-Mailer: git-send-email 2.17.0 Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org 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 --- 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 9a59a1b54c97..a962abce98f8 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, @@ -362,6 +370,7 @@ 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); } -- 2.17.0