From patchwork Mon Apr 27 21:55:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Evan Green X-Patchwork-Id: 226952 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=-9.9 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, 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 89DFFC81857 for ; Mon, 27 Apr 2020 21:55:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6900C2074F for ; Mon, 27 Apr 2020 21:55:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="LbaJb+ki" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726285AbgD0Vzz (ORCPT ); Mon, 27 Apr 2020 17:55:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48076 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726204AbgD0Vzy (ORCPT ); Mon, 27 Apr 2020 17:55:54 -0400 Received: from mail-pf1-x441.google.com (mail-pf1-x441.google.com [IPv6:2607:f8b0:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6467EC0610D5 for ; Mon, 27 Apr 2020 14:55:53 -0700 (PDT) Received: by mail-pf1-x441.google.com with SMTP id x2so5941217pfx.7 for ; Mon, 27 Apr 2020 14:55:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=QwWrKenZ8k5J4q1qBIr58HlyfL2ByZs2Ssa6TCedrSk=; b=LbaJb+ki6pK6wQO0c2DyS9Atvm8JE6MKeoBDclHbQycrzujPTZPNaK6yfuGS3UUBu/ MInl24vMoRUBTYFpBgQQbK46u9WS6P1ReSzyapOuUjnUuuNUi6RCCGHwAfTpbIGsUaQD pZuvHsXY0pF9NwVYLOImYaZhrERGyHEWxmM18= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=QwWrKenZ8k5J4q1qBIr58HlyfL2ByZs2Ssa6TCedrSk=; b=bS0S0cGMlzElZn6XMWM6ALReRYtjykhui6wOXlf59CICLCKaUw+VA9EhbP+pfZFWcG jE61MY/hABTKdZunKGGz9EsqREBH/7SmuygtUUiLDvqamPPb9R0zDR4jz0z1Zyxywt4q w/b4qyIxJW2ERo9E+w4X3dVjfSEkXU4yiIF6vwMlK0UgRfMsQC+Vk7KqRSrgJ4Y9IJ7w nUQtHSfHu/5zOOsrQ9TEpC7ePvZ7n8NvPeHjcWW6LrK+x/fEUJlkF35+6VK0Ao+gAZV8 nUltXLCnQ/fo1APQAQDE8uON40bT0qmY3GdNJUa3pzVTouo4ej3HvJoJ7j29LfkELzzQ n6UA== X-Gm-Message-State: AGi0PuaBB9guSBpgCJ3VxGlxn357TOdPDRXm4SslYrJNBgQh3Tp1RZgY eoBFWa12l+e/Jhk4kmxOhU/M5Q== X-Google-Smtp-Source: APiQypIWIg1lh3l6rgxN7SYiYVoPklma36XNRFiHNukzSWdE1PdM5v8sHQNeaE1NgWaTUlxWGHzTWw== X-Received: by 2002:a62:c1c1:: with SMTP id i184mr27417512pfg.18.1588024552819; Mon, 27 Apr 2020 14:55:52 -0700 (PDT) Received: from evgreen-glaptop.cheshire.ch ([2601:646:c780:1404:1c5a:73fa:6d5a:5a3c]) by smtp.gmail.com with ESMTPSA id f99sm244273pjg.22.2020.04.27.14.55.51 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Mon, 27 Apr 2020 14:55:52 -0700 (PDT) From: Evan Green To: Dmitry Torokhov Cc: Evan Green , stable@vger.kernel.org, Nick Desaulniers , Allison Randal , Andrew Duggan , Benjamin Tissoires , Enrico Weigelt , Thomas Gleixner , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] Input: synaptics-rmi4 - Really fix attn_data use-after-free Date: Mon, 27 Apr 2020 14:55:48 -0700 Message-Id: <20200427145537.1.Ic8f898e0147beeee2c005ee7b20f1aebdef1e7eb@changeid> X-Mailer: git-send-email 2.24.1 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 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 Cc: Nick Desaulniers --- 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 190b9974526bb..c18e1a25bca6e 100644 --- a/drivers/input/rmi4/rmi_driver.c +++ b/drivers/input/rmi4/rmi_driver.c @@ -205,7 +205,7 @@ 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))