From patchwork Wed Jun 16 12:28:27 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mauro Carvalho Chehab X-Patchwork-Id: 12324979 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=-16.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 05C96C49361 for ; Wed, 16 Jun 2021 12:28:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DE534613E9 for ; Wed, 16 Jun 2021 12:28:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232971AbhFPMa5 (ORCPT ); Wed, 16 Jun 2021 08:30:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:49294 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232535AbhFPMaq (ORCPT ); Wed, 16 Jun 2021 08:30:46 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 94CE2613C7; Wed, 16 Jun 2021 12:28:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1623846520; bh=oqjheYG9h6Tj93iYGW/qpgENpt3aGXsa0799OrvQ9yI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AlcLOffiFWXL5cRggUltDdgmSWK6JreQRh0+Olh8oMZfUiMTrMymEZkeseIhwfBaU +4wOSWMtGOqYlVuXi6TIHcO5OS7ZZ88Ljk0RDP19GXhLkXPYeldowC46VDcU7cTN4x c+gklEMaGu5KuWBPOuHjQogcSzK85fqYjSC1Qj1kjW7K27PTlBeTHmiczYkQ25WR4Q 2n4xyNQFOV8+8n6rvMJkDcMOlqBmblJdt4IWXba6Hkfvq27iAPCv5B5SLzuKmeinZN LmqCGUb3AJATNlhbI4+lTaU4mNgUZmotnNWdcuLAdfj0WTmx25hMRnDmUfTKQPl6T/ kGUS7Pq7VboEw== Received: by mail.kernel.org with local (Exim 4.94.2) (envelope-from ) id 1ltUes-004oiP-7C; Wed, 16 Jun 2021 14:28:38 +0200 From: Mauro Carvalho Chehab Cc: linuxarm@huawei.com, mauro.chehab@huawei.com, Mauro Carvalho Chehab , Hans Verkuil , Mauro Carvalho Chehab , linux-kernel@vger.kernel.org, linux-media@vger.kernel.org Subject: [PATCH 01/11] media: dvb_ca_en50221: avoid speculation from CA slot Date: Wed, 16 Jun 2021 14:28:27 +0200 Message-Id: <77322db90902cd2c9d25fa3d614bf25809e9c609.1623846327.git.mchehab+huawei@kernel.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: References: MIME-Version: 1.0 Sender: Mauro Carvalho Chehab To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org As warned by smatch: drivers/media/dvb-core/dvb_ca_en50221.c:1392 dvb_ca_en50221_io_do_ioctl() warn: potential spectre issue 'ca->slot_info' [r] (local cap) There's a potential of using a CAM ioctl for speculation. The risk here is minimum, as only a small subset of DVB boards have CI, with a CAM module installed. Also, exploiting it would require an user capable of starting a DVB application. There are probably a lot of easier ways to try to exploit. Yet, it doesn't harm addressing it. Signed-off-by: Mauro Carvalho Chehab --- drivers/media/dvb-core/dvb_ca_en50221.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/media/dvb-core/dvb_ca_en50221.c b/drivers/media/dvb-core/dvb_ca_en50221.c index b7e4a3371176..15a08d8c69ef 100644 --- a/drivers/media/dvb-core/dvb_ca_en50221.c +++ b/drivers/media/dvb-core/dvb_ca_en50221.c @@ -1386,6 +1386,7 @@ static int dvb_ca_en50221_io_do_ioctl(struct file *file, err = -EINVAL; goto out_unlock; } + slot = array_index_nospec(slot, ca->slot_count); info->type = CA_CI_LINK; info->flags = 0;