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 94C55CCA479 for ; Mon, 20 Jun 2022 13:06:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244950AbiFTNGI (ORCPT ); Mon, 20 Jun 2022 09:06:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47366 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244819AbiFTNEC (ORCPT ); Mon, 20 Jun 2022 09:04:02 -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 15542192B2; Mon, 20 Jun 2022 05:58:45 -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 A6AE361449; Mon, 20 Jun 2022 12:58:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 95FA8C341C4; Mon, 20 Jun 2022 12:58:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1655729924; bh=7HXLfzXZPKUoSFxq2zbCBvTU5X7bq2SjOdG0EnWubOU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YSi8t9i0qB8tkZHs+DZh0eZtPwNv6myZX0RB7cLb9qmNWVMBoUDDtVjRVuGQNODB6 W3/MExqo50blkL3NVIucNkvLERFTqhuejptvlJudb772Qj0DrmvEC/b/h5ki0RTmDF EdT+LzisWx4u5HgsWEeHePfZ+k1e5B9q0SLQAQ/Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Shinichiro Kawasaki Subject: [PATCH 5.18 117/141] bus: fsl-mc-bus: fix KASAN use-after-free in fsl_mc_bus_remove() Date: Mon, 20 Jun 2022 14:50:55 +0200 Message-Id: <20220620124733.007864957@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220620124729.509745706@linuxfoundation.org> References: <20220620124729.509745706@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Shin'ichiro Kawasaki commit 928ea98252ad75118950941683893cf904541da9 upstream. In fsl_mc_bus_remove(), mc->root_mc_bus_dev->mc_io is passed to fsl_destroy_mc_io(). However, mc->root_mc_bus_dev is already freed in fsl_mc_device_remove(). Then reference to mc->root_mc_bus_dev->mc_io triggers KASAN use-after-free. To avoid the use-after-free, keep the reference to mc->root_mc_bus_dev->mc_io in a local variable and pass to fsl_destroy_mc_io(). This patch needs rework to apply to kernels older than v5.15. Fixes: f93627146f0e ("staging: fsl-mc: fix asymmetry in destroy of mc_io") Cc: stable@vger.kernel.org # v5.15+ Signed-off-by: Shin'ichiro Kawasaki Link: https://lore.kernel.org/r/20220601105159.87752-1-shinichiro.kawasaki@wdc.com Signed-off-by: Greg Kroah-Hartman --- drivers/bus/fsl-mc/fsl-mc-bus.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/bus/fsl-mc/fsl-mc-bus.c +++ b/drivers/bus/fsl-mc/fsl-mc-bus.c @@ -1236,14 +1236,14 @@ error_cleanup_mc_io: static int fsl_mc_bus_remove(struct platform_device *pdev) { struct fsl_mc *mc = platform_get_drvdata(pdev); + struct fsl_mc_io *mc_io; if (!fsl_mc_is_root_dprc(&mc->root_mc_bus_dev->dev)) return -EINVAL; + mc_io = mc->root_mc_bus_dev->mc_io; fsl_mc_device_remove(mc->root_mc_bus_dev); - - fsl_destroy_mc_io(mc->root_mc_bus_dev->mc_io); - mc->root_mc_bus_dev->mc_io = NULL; + fsl_destroy_mc_io(mc_io); bus_unregister_notifier(&fsl_mc_bus_type, &fsl_mc_nb);