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=-6.8 required=3.0 tests=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 7C985C55189 for ; Wed, 22 Apr 2020 10:54:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4F6912076E for ; Wed, 22 Apr 2020 10:54:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587552881; bh=Zb2q7FIeXzFHGV5URxwb82rv0SspNQ/Ggeon+/n54N8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=uw8Vudx4c7hUVTBgb+gxxAahb2WOe4zn7F+Ko9SdiyuHNObZ9SB0EKIV8UoXwDDPW FMc09kBDOqePltK4es/oAihyI5eqii201wqxATYAud9Jvm/wjFyQlFEIlr36eqh6AS MuTnRoCLaHNsge0Zjhgb7SEHgU+UEQC5ywhOsdQs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729173AbgDVKyk (ORCPT ); Wed, 22 Apr 2020 06:54:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:60424 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726948AbgDVKHk (ORCPT ); Wed, 22 Apr 2020 06:07:40 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 8EE4820575; Wed, 22 Apr 2020 10:07:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587550060; bh=Zb2q7FIeXzFHGV5URxwb82rv0SspNQ/Ggeon+/n54N8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=alF0iQBTggxEjsRPbZa8n+yYKBqrksmUaef/jw8HzG4WcTm6TYH10i/TrEsUAZJnK I0rd4F8kIXIQLH+EMVpNef64slDLMpkvnIexpQpIEjO4A2wqkwlwUuwvIt+U56LD/h 3FXcwTl2zrJSMJb8TXVYpe+ONJ4BP6JbG7Z8rbW8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Andrew Morton , Arnd Bergmann , "Eric W. Biederman" , Andrea Righi , Daniel Vetter , Sam Ravnborg , Maarten Lankhorst , Daniel Thompson , Peter Rosin , Jani Nikula , Gerd Hoffmann , Bartlomiej Zolnierkiewicz Subject: [PATCH 4.9 118/125] fbdev: potential information leak in do_fb_ioctl() Date: Wed, 22 Apr 2020 11:57:15 +0200 Message-Id: <20200422095051.648271141@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200422095032.909124119@linuxfoundation.org> References: <20200422095032.909124119@linuxfoundation.org> User-Agent: quilt/0.66 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 From: Dan Carpenter commit d3d19d6fc5736a798b118971935ce274f7deaa82 upstream. The "fix" struct has a 2 byte hole after ->ywrapstep and the "fix = info->fix;" assignment doesn't necessarily clear it. It depends on the compiler. The solution is just to replace the assignment with an memcpy(). Fixes: 1f5e31d7e55a ("fbmem: don't call copy_from/to_user() with mutex held") Signed-off-by: Dan Carpenter Cc: Andrew Morton Cc: Arnd Bergmann Cc: "Eric W. Biederman" Cc: Andrea Righi Cc: Daniel Vetter Cc: Sam Ravnborg Cc: Maarten Lankhorst Cc: Daniel Thompson Cc: Peter Rosin Cc: Jani Nikula Cc: Gerd Hoffmann Signed-off-by: Bartlomiej Zolnierkiewicz Link: https://patchwork.freedesktop.org/patch/msgid/20200113100132.ixpaymordi24n3av@kili.mountain Signed-off-by: Greg Kroah-Hartman --- drivers/video/fbdev/core/fbmem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1132,7 +1132,7 @@ static long do_fb_ioctl(struct fb_info * case FBIOGET_FSCREENINFO: if (!lock_fb_info(info)) return -ENODEV; - fix = info->fix; + memcpy(&fix, &info->fix, sizeof(fix)); unlock_fb_info(info); ret = copy_to_user(argp, &fix, sizeof(fix)) ? -EFAULT : 0;