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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 73006C2BBC7 for ; Sat, 11 Apr 2020 23:30:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 465422051A for ; Sat, 11 Apr 2020 23:30:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586647803; bh=NY7ZqzCJPWeys9vGU83DhxaZTUXXDJycIFv3gVHjUyI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=U4c8iKXfkb64RaXywi/rzTwOvMc+3nwYQJm3yFAkGtR9gzcui5rJqVGTXQheZXIYs x5IkRVqWsnElFlA/+RugMpYZfRych57BVj16Iq1hlTvz17llG5gPRtmi2U/0jTTzyq 7QVBmGX0sBa5uTUc1/PZrhcY4BecjGEcQJTwjzjU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729205AbgDKX36 (ORCPT ); Sat, 11 Apr 2020 19:29:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:49590 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729680AbgDKXKs (ORCPT ); Sat, 11 Apr 2020 19:10:48 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 723FA2173E; Sat, 11 Apr 2020 23:10:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586646648; bh=NY7ZqzCJPWeys9vGU83DhxaZTUXXDJycIFv3gVHjUyI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bJyci6K/QotL/BB9uFCcZRuv9qj4/9ljkevMx4iH0T3RJKFUsgX1GCLKbq0YmMme5 QAlba5h2fvGLn5/jTwKjomGPlgWEU6EPCgVRRkb6Q1AuKrsTsrB1GMms5ydHbFiRq8 aBDXzx3DbQjo9ofuuOuO02fKpbXq5R4/rPY3frvw= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: 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 , Sasha Levin , dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org Subject: [PATCH AUTOSEL 5.4 052/108] fbdev: potential information leak in do_fb_ioctl() Date: Sat, 11 Apr 2020 19:08:47 -0400 Message-Id: <20200411230943.24951-52-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200411230943.24951-1-sashal@kernel.org> References: <20200411230943.24951-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Dan Carpenter [ Upstream commit d3d19d6fc5736a798b118971935ce274f7deaa82 ] 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: Sasha Levin --- drivers/video/fbdev/core/fbmem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index e6a1c805064f0..36469943795a8 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1110,7 +1110,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd, 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); -- 2.20.1