From patchwork Tue Sep 1 15:10:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 264784 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=-10.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,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 BD5BFC433E7 for ; Tue, 1 Sep 2020 15:24:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 84BFD20FC3 for ; Tue, 1 Sep 2020 15:24:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598973895; bh=mI2ix3jDcTd6+yitBSFLtIfCRzJi7p2SJWcUmdKPOQU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ikLvuUOUGs2C0GvKYWLvvNmrL/cu6LtYqfcKGm+V9M0Iz2GRiEPvgoFcj4fiysf9G ns3meDiOLiR5oxzdl1S+1sQOkDix1bE1c+0Ki9mL/n6WL1vDoyzYk2Ge/iLzlLKAUo zqKEckWOUdIqRPHw74wKm7AZPiYyKDonTxBGhLkQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729981AbgIAPYx (ORCPT ); Tue, 1 Sep 2020 11:24:53 -0400 Received: from mail.kernel.org ([198.145.29.99]:48892 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728720AbgIAPYw (ORCPT ); Tue, 1 Sep 2020 11:24:52 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 7C5242078B; Tue, 1 Sep 2020 15:24:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598973892; bh=mI2ix3jDcTd6+yitBSFLtIfCRzJi7p2SJWcUmdKPOQU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=i+QQTq9HG5QQhQWy1cTS6Uzk8btU7GGg5PY9q4gz1X/LT9HSHQuJubjurgOJIlYj0 0vdSB+qkWmncRZWTuISR9XQcPx6Kr38uoX+8AmEh/HuAKpVKIOxN4B8RnGhEYbjqec duhty0sposNLo6fYOhMoVlG3hAOEIEQ/A1WS8dV8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, George Kennedy , syzbot+38a3699c7eaf165b97a6@syzkaller.appspotmail.com Subject: [PATCH 4.19 088/125] vt_ioctl: change VT_RESIZEX ioctl to check for error return from vc_resize() Date: Tue, 1 Sep 2020 17:10:43 +0200 Message-Id: <20200901150938.891267321@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200901150934.576210879@linuxfoundation.org> References: <20200901150934.576210879@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: George Kennedy commit bc5269ca765057a1b762e79a1cfd267cd7bf1c46 upstream. vc_resize() can return with an error after failure. Change VT_RESIZEX ioctl to save struct vc_data values that are modified and restore the original values in case of error. Signed-off-by: George Kennedy Cc: stable Reported-by: syzbot+38a3699c7eaf165b97a6@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/1596213192-6635-2-git-send-email-george.kennedy@oracle.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/vt/vt_ioctl.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) --- a/drivers/tty/vt/vt_ioctl.c +++ b/drivers/tty/vt/vt_ioctl.c @@ -893,12 +893,22 @@ int vt_ioctl(struct tty_struct *tty, console_lock(); vcp = vc_cons[i].d; if (vcp) { + int ret; + int save_scan_lines = vcp->vc_scan_lines; + int save_font_height = vcp->vc_font.height; + if (v.v_vlin) vcp->vc_scan_lines = v.v_vlin; if (v.v_clin) vcp->vc_font.height = v.v_clin; vcp->vc_resize_user = 1; - vc_resize(vcp, v.v_cols, v.v_rows); + ret = vc_resize(vcp, v.v_cols, v.v_rows); + if (ret) { + vcp->vc_scan_lines = save_scan_lines; + vcp->vc_font.height = save_font_height; + console_unlock(); + return ret; + } } console_unlock(); }