From patchwork Mon Jun 1 17:53:35 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: 224888 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, 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 64707C433DF for ; Mon, 1 Jun 2020 18:56:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3AB75206C3 for ; Mon, 1 Jun 2020 18:56:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591037799; bh=fBZvDbLjHpbUJL2gKLdLwRD4VPHSZY8vhp3Jox947ek=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xLPd/gMWUX36UmnhUXnsS/DVnnl+5xErCW+SrkS4K9W/SKhxBO+aPnEDrrZUlb5gw +G8diS9OFPYMUfyUBdzq6pVvCkqaKmvnRB9/hvwJ8AgpEOfhtKVYMdBGPnvxFgtMty MGgIjc3ZRV40Fs4xEBGwDqd7kECdpOtE7OAnf/oA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729604AbgFASAf (ORCPT ); Mon, 1 Jun 2020 14:00:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:43302 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729118AbgFASAf (ORCPT ); Mon, 1 Jun 2020 14:00:35 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 C609B2065C; Mon, 1 Jun 2020 18:00:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591034434; bh=fBZvDbLjHpbUJL2gKLdLwRD4VPHSZY8vhp3Jox947ek=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=txeKoefR3HBvGZfXS/xjSn/S1jlIeAjA34pWUcX0+yOR1z6HAW4VZOlc6j2Q1+bB9 Jf80Jj1eC3XCmR71cEGOuMU7wqlp36okopjORffULK951Do2um3JweVSZdS+PZeZVd Z7GptCi9rug3SeJfVfxzlYuPLFKuXZEKCm6JFbxM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Evan Green , Dmitry Torokhov , Sasha Levin Subject: [PATCH 4.14 30/77] Input: synaptics-rmi4 - really fix attn_data use-after-free Date: Mon, 1 Jun 2020 19:53:35 +0200 Message-Id: <20200601174022.046583793@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200601174016.396817032@linuxfoundation.org> References: <20200601174016.396817032@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Evan Green [ Upstream commit d5a5e5b5fa7b86c05bf073acc0ba98fa280174ec ] Fix a use-after-free noticed by running with KASAN enabled. If rmi_irq_fn() is run twice in a row, then rmi_f11_attention() (among others) will end up reading from drvdata->attn_data.data, which was freed and left dangling in rmi_irq_fn(). Commit 55edde9fff1a ("Input: synaptics-rmi4 - prevent UAF reported by KASAN") correctly identified and analyzed this bug. However the attempted fix only NULLed out a local variable, missing the fact that drvdata->attn_data is a struct, not a pointer. NULL out the correct pointer in the driver data to prevent the attention functions from copying from it. Fixes: 55edde9fff1a ("Input: synaptics-rmi4 - prevent UAF reported by KASAN") Fixes: b908d3cd812a ("Input: synaptics-rmi4 - allow to add attention data") Signed-off-by: Evan Green Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200427145537.1.Ic8f898e0147beeee2c005ee7b20f1aebdef1e7eb@changeid Signed-off-by: Dmitry Torokhov Signed-off-by: Sasha Levin --- drivers/input/rmi4/rmi_driver.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/input/rmi4/rmi_driver.c b/drivers/input/rmi4/rmi_driver.c index 997ccae7ee05..633fd0d660c1 100644 --- a/drivers/input/rmi4/rmi_driver.c +++ b/drivers/input/rmi4/rmi_driver.c @@ -232,7 +232,7 @@ static irqreturn_t rmi_irq_fn(int irq, void *dev_id) if (count) { kfree(attn_data.data); - attn_data.data = NULL; + drvdata->attn_data.data = NULL; } if (!kfifo_is_empty(&drvdata->attn_fifo))