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=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 EEF48C282D7 for ; Mon, 11 Feb 2019 15:52:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B1A9121855 for ; Mon, 11 Feb 2019 15:52:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549900363; bh=q1OdszwJa/2UkE+YbLygIPqEgEoN4H82mQWtPP0SXMM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=dv9gz4zqpfuiRbyXjLY4pi0eWwKk5lMYqr4dVx8PqC1+g7iB+H5VxuuKjDQ9U/AXL euVr6LeZboyhVxXJp11rVeu10tKIHjSjPDbkwZNHnPJF6p8RUwmpZiCv91Xk7ukIq4 pc3gfqNwPxU2dbiGOeaumaQ65848Xqkm0A1r1Jyg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730726AbfBKOhK (ORCPT ); Mon, 11 Feb 2019 09:37:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:46442 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731393AbfBKOhJ (ORCPT ); Mon, 11 Feb 2019 09:37:09 -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 E41D720844; Mon, 11 Feb 2019 14:37:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549895828; bh=q1OdszwJa/2UkE+YbLygIPqEgEoN4H82mQWtPP0SXMM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wdQwIVZU8tWCb7tGXMP+Co8Z8nhVZNVuIn3iY1UhGTx5Vq+6fVOhKGBrthhGcqZwf HE5GjXFg3H/mEzlyWfhHTVMnXMQL5W4VP00cAF6P4jxaLwtdMZfXZM7AhrP7m5kcH5 3fCn8M3j4YKiLhSdL4//u2RvvHtrTgNznRJw+nQI= 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 4.20 335/352] staging: speakup: fix tty-operation NULL derefs Date: Mon, 11 Feb 2019 15:19:22 +0100 Message-Id: <20190211141908.392171881@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190211141846.543045703@linuxfoundation.org> References: <20190211141846.543045703@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: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.20-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); }