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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 35655C433B4 for ; Mon, 5 Apr 2021 09:00:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EB22D60238 for ; Mon, 5 Apr 2021 09:00:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237204AbhDEJAk (ORCPT ); Mon, 5 Apr 2021 05:00:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:41098 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236524AbhDEI7z (ORCPT ); Mon, 5 Apr 2021 04:59:55 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id C1B43613B0; Mon, 5 Apr 2021 08:59:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1617613189; bh=dB2GI0K51dN1Sl0JccgDDEk+G5HBCHCUHclBpalLCxI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XrR8b78km1Y74qoJxYqW1dAYvpZ64f6jhe9I8QbAolceEPOhGy4ll53msUqH5OWWx Q1f66jElCe6M9e2oHWlSoQv/590D5CyhR+dFlQfuNNCh98PbdrRgsKnckPSQDFnnth tyLZh/cJZ6hrosg+0jm6kP5uIbKkrnqwV4qNIczs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+b67aaae8d3a927f68d20@syzkaller.appspotmail.com, Du Cheng Subject: [PATCH 4.14 52/52] drivers: video: fbcon: fix NULL dereference in fbcon_cursor() Date: Mon, 5 Apr 2021 10:54:18 +0200 Message-Id: <20210405085023.681659437@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210405085021.996963957@linuxfoundation.org> References: <20210405085021.996963957@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Du Cheng commit 01faae5193d6190b7b3aa93dae43f514e866d652 upstream. add null-check on function pointer before dereference on ops->cursor Reported-by: syzbot+b67aaae8d3a927f68d20@syzkaller.appspotmail.com Cc: stable Signed-off-by: Du Cheng Link: https://lore.kernel.org/r/20210312081421.452405-1-ducheng2@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/video/fbdev/core/fbcon.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -1284,6 +1284,9 @@ static void fbcon_cursor(struct vc_data ops->cursor_flash = (mode == CM_ERASE) ? 0 : 1; + if (!ops->cursor) + return; + ops->cursor(vc, info, mode, get_color(vc, info, c, 1), get_color(vc, info, c, 0)); }