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 8E7FFC55186 for ; Wed, 22 Apr 2020 10:27:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 606342084D for ; Wed, 22 Apr 2020 10:27:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587551228; bh=7hvtoSzxmi+cP8AANifV0v8cp0KWUwU7mn9hHs/Izno=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=WKs5YkHLzakyAhQHlvLHFO5eSoGQ9+EWz0GOEOF9PCKOTxdpQ9jnxkrExFn4YITCp j+/2Ic5EJ6mZANbJs0kUYs7qOvCgOUMclcghBJrgP0++/tfxjhs5Ua5a24Z0joHl5u COt3jFiUj3Om9CK7e+U6oHlWy0Mj+7SUvG8D16qM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730830AbgDVK1H (ORCPT ); Wed, 22 Apr 2020 06:27:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:36004 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730805AbgDVK1F (ORCPT ); Wed, 22 Apr 2020 06:27:05 -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 F15AB20781; Wed, 22 Apr 2020 10:27:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1587551224; bh=7hvtoSzxmi+cP8AANifV0v8cp0KWUwU7mn9hHs/Izno=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WGbETPv9eIQCndTnPQd9JXlY+08qu93pudt46qJo6fB+1tSrccEccMI54aDjajvC7 xpctACUTTaYHLYpPmPnSqXCxyVpUsLmmFjUS7+RW0EKLT8xumLSx92VgWhqhaXZB7s MyKEpVVZ3ahrT/Dv0KPv9V62xDDskJbTc07LUPL4= 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 5.6 150/166] fbdev: potential information leak in do_fb_ioctl() Date: Wed, 22 Apr 2020 11:57:57 +0200 Message-Id: <20200422095104.660409122@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200422095047.669225321@linuxfoundation.org> References: <20200422095047.669225321@linuxfoundation.org> User-Agent: quilt/0.66 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 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 @@ -1115,7 +1115,7 @@ static long do_fb_ioctl(struct fb_info * break; case FBIOGET_FSCREENINFO: lock_fb_info(info); - fix = info->fix; + memcpy(&fix, &info->fix, sizeof(fix)); if (info->flags & FBINFO_HIDE_SMEM_START) fix.smem_start = 0; unlock_fb_info(info);