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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 DB1D3C433DF for ; Mon, 8 Jun 2020 23:58:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B0ABB2078D for ; Mon, 8 Jun 2020 23:58:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591660734; bh=9/zpqtvcvi/aDsfbxPRxBceob0fFvjcGLgPlCn/Du6Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=xLI1Jr5m3hNyJocPQ4WYRDMc8oQNdBuC1tvGQhhCnXmI6Ox5F35A77z49K0hAGPXs 9PhPeS2lFL9uHL1GULQzLhlvixrV1ge0+iWjysNqWhuaxgxc2lEuYjOHMKAe8GGo27 uSjCRTnRJggUJT6uf/d24pRCKz33Im5DJj7blppI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731441AbgFHXXH (ORCPT ); Mon, 8 Jun 2020 19:23:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:40308 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729070AbgFHXSL (ORCPT ); Mon, 8 Jun 2020 19:18:11 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EB5052083E; Mon, 8 Jun 2020 23:18:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591658291; bh=9/zpqtvcvi/aDsfbxPRxBceob0fFvjcGLgPlCn/Du6Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ksueB7PYm8KRNguIr9Q/tkdu0AOoxKY6JLEv3vNoOJbMQ3t226RBmsVNR97BvIMJn lZxzOomoVWQfQYMiJzQ4YXK8x78tE4BGyRP/HPglS5nx/eGx96T6As0WX/z5bMvkZJ KhYXMaQGGCCSOvDTBfWmgaVr8bEPIc506OgSg7ww= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Evan Green , Dmitry Torokhov , Sasha Levin , linux-input@vger.kernel.org Subject: [PATCH AUTOSEL 5.6 295/606] Input: synaptics-rmi4 - really fix attn_data use-after-free Date: Mon, 8 Jun 2020 19:07:00 -0400 Message-Id: <20200608231211.3363633-295-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200608231211.3363633-1-sashal@kernel.org> References: <20200608231211.3363633-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 190b9974526b..c18e1a25bca6 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)) -- 2.25.1