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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,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 CF4ECC169C4 for ; Mon, 11 Feb 2019 14:53:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F14020700 for ; Mon, 11 Feb 2019 14:53:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549896780; bh=6OMHWJARGIz5ndA6wiiDGYEU0FmRjK0nN3O116FWQBk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=aShQZPQHwqROMp/gZbP3ouPvhSaS0E5+hNdsj6SOoveEdhMz3DGZNsrqqD1DUZkHY fqeLTeT56hUZ/ntKtuzlKZNdQoFrIq1h5C6G5B1ODfTHllmtYZZZLq12EkNONcs6De gNt9N6AWmcESratF70tqL7wh/SMCJNvS19BnXxEY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388541AbfBKOw6 (ORCPT ); Mon, 11 Feb 2019 09:52:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:39266 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388525AbfBKOwx (ORCPT ); Mon, 11 Feb 2019 09:52:53 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.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 BE0BF20855; Mon, 11 Feb 2019 14:52:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549896773; bh=6OMHWJARGIz5ndA6wiiDGYEU0FmRjK0nN3O116FWQBk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qlUhGl0qnu4HHRdpHrFFzLwuXgwhB/PuL11VSOP/lCdzb1aY0bevwdNpiDs5Vr485 v56rGYH9ky25L7UAl3bhNDXtvuDlAq5VqS1paLCxQofcpUOgWX5CvYfe/3Ct0P7qfA oVfas5SSBP9Mkvj9jtzUgdeVDIMggxCLu9V8oYmg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Okash Khawaja , Samuel Thibault , Johan Hovold Subject: [PATCH 4.19 297/313] staging: speakup: fix tty-operation NULL derefs Date: Mon, 11 Feb 2019 15:19:37 +0100 Message-Id: <20190211141912.807453080@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190211141852.749630980@linuxfoundation.org> References: <20190211141852.749630980@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit a1960e0f1639cb1f7a3d94521760fc73091f6640 upstream. The send_xchar() and tiocmset() tty operations are optional. Add the missing sanity checks to prevent user-space triggerable NULL-pointer dereferences. Fixes: 6b9ad1c742bf ("staging: speakup: add send_xchar, tiocmset and input functionality for tty") Cc: stable # 4.13 Cc: Okash Khawaja Cc: Samuel Thibault Signed-off-by: Johan Hovold Reviewed-by: Samuel Thibault Signed-off-by: Greg Kroah-Hartman --- drivers/staging/speakup/spk_ttyio.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/staging/speakup/spk_ttyio.c +++ b/drivers/staging/speakup/spk_ttyio.c @@ -265,7 +265,8 @@ static void spk_ttyio_send_xchar(char ch return; } - speakup_tty->ops->send_xchar(speakup_tty, ch); + if (speakup_tty->ops->send_xchar) + speakup_tty->ops->send_xchar(speakup_tty, ch); mutex_unlock(&speakup_tty_mutex); } @@ -277,7 +278,8 @@ static void spk_ttyio_tiocmset(unsigned return; } - speakup_tty->ops->tiocmset(speakup_tty, set, clear); + if (speakup_tty->ops->tiocmset) + speakup_tty->ops->tiocmset(speakup_tty, set, clear); mutex_unlock(&speakup_tty_mutex); }