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=-8.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT 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 1EBD0C43387 for ; Wed, 16 Jan 2019 15:00:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E0880205C9 for ; Wed, 16 Jan 2019 15:00:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b="sfYEvZdI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2393788AbfAPPAP (ORCPT ); Wed, 16 Jan 2019 10:00:15 -0500 Received: from vps0.lunn.ch ([185.16.172.187]:45309 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728675AbfAPPAP (ORCPT ); Wed, 16 Jan 2019 10:00:15 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date; bh=FAJnXUUIubJJzqURBD3F7bfBh9AUxwlewlTQHGPdEOU=; b=sfYEvZdI7qX1qFsR8i4TOxgaVXF7wF4jLvIN0nDZSbEVK0htRr8Euk7W229GW4uFSSZxhyfOlr3obdqbp8l9Z1sMlsf1AzxhV3DFGY7psSJ+m+3N9CR3XxnAlBr0u+6eOT7g4v6Nd778t2G4539dKY2sys+EML0xmrGY7RnAHyI=; Received: from andrew by vps0.lunn.ch with local (Exim 4.84_2) (envelope-from ) id 1gjmfp-0007PC-Kp; Wed, 16 Jan 2019 16:00:09 +0100 Date: Wed, 16 Jan 2019 16:00:09 +0100 From: Andrew Lunn To: Johan Hovold Cc: Hauke Mehrtens , Vivien Didelot , Florian Fainelli , "David S. Miller" , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, stable Subject: Re: [PATCH 1/3] net: dsa: lantiq_gswip: fix use-after-free on failed probe Message-ID: <20190116150009.GE25731@lunn.ch> References: <20190116102335.30433-1-johan@kernel.org> <20190116102335.30433-2-johan@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190116102335.30433-2-johan@kernel.org> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 16, 2019 at 11:23:33AM +0100, Johan Hovold wrote: > Make sure to disable and deregister the switch on late probe errors to > avoid use-after-free when the device-resource-managed switch is freed. > > Fixes: 14fceff4771e ("net: dsa: Add Lantiq / Intel DSA driver for vrx200") > Cc: stable # 4.20 > Cc: Hauke Mehrtens > Signed-off-by: Johan Hovold > --- > drivers/net/dsa/lantiq_gswip.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/dsa/lantiq_gswip.c b/drivers/net/dsa/lantiq_gswip.c > index 693a67f45bef..b06c41c98de9 100644 > --- a/drivers/net/dsa/lantiq_gswip.c > +++ b/drivers/net/dsa/lantiq_gswip.c > @@ -1099,7 +1099,7 @@ static int gswip_probe(struct platform_device *pdev) > dev_err(dev, "wrong CPU port defined, HW only supports port: %i", > priv->hw_info->cpu_port); > err = -EINVAL; > - goto mdio_bus; > + goto disable_switch; > } > > platform_set_drvdata(pdev, priv); > @@ -1109,6 +1109,9 @@ static int gswip_probe(struct platform_device *pdev) > (version & GSWIP_VERSION_MOD_MASK) >> GSWIP_VERSION_MOD_SHIFT); > return 0; > > +disable_switch: > + gswip_mdio_mask(priv, GSWIP_MDIO_GLOB_ENABLE, 0, GSWIP_MDIO_GLOB); > + dsa_unregister_switch(priv->ds); This is correct. But it would be nice if somebody in the future could move the disabling of the switch to the inverse of the gswip_setup() function to make the code symmetrical. Reviewed-by: Andrew Lunn Andrew