From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933671Ab1DNR5q (ORCPT ); Thu, 14 Apr 2011 13:57:46 -0400 Received: from mail.windriver.com ([147.11.1.11]:41431 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933236Ab1DNR5o (ORCPT ); Thu, 14 Apr 2011 13:57:44 -0400 From: Paul Gortmaker To: stable@kernel.org, linux-kernel@vger.kernel.org Cc: stable-review@kernel.org, Dan Rosenberg , Dan Rosenberg , Andy Walls , Mauro Carvalho Chehab , Paul Gortmaker Subject: [34-longterm 117/209] V4L/DVB: ivtvfb: prevent reading uninitialized stack memory Date: Thu, 14 Apr 2011 13:54:35 -0400 Message-Id: <1302803767-9715-4-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.7.4.4 In-Reply-To: <1302803767-9715-1-git-send-email-paul.gortmaker@windriver.com> References: <1302803039-9400-1-git-send-email-paul.gortmaker@windriver.com> <1302803767-9715-1-git-send-email-paul.gortmaker@windriver.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dan Rosenberg ===================================================================== | This is a commit scheduled for the next v2.6.34 longterm release. | | If you see a problem with using this for longterm, please comment.| ===================================================================== commit 405707985594169cfd0b1d97d29fcb4b4c6f2ac9 upstream. The FBIOGET_VBLANK device ioctl allows unprivileged users to read 16 bytes of uninitialized stack memory, because the "reserved" member of the fb_vblank struct declared on the stack is not altered or zeroed before being copied back to the user. This patch takes care of it. Signed-off-by: Dan Rosenberg Signed-off-by: Andy Walls Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Paul Gortmaker --- drivers/media/video/ivtv/ivtvfb.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/drivers/media/video/ivtv/ivtvfb.c b/drivers/media/video/ivtv/ivtvfb.c index de2ff1c..e320b7e 100644 --- a/drivers/media/video/ivtv/ivtvfb.c +++ b/drivers/media/video/ivtv/ivtvfb.c @@ -458,6 +458,8 @@ static int ivtvfb_ioctl(struct fb_info *info, unsigned int cmd, unsigned long ar struct fb_vblank vblank; u32 trace; + memset(&vblank, 0, sizeof(struct fb_vblank)); + vblank.flags = FB_VBLANK_HAVE_COUNT |FB_VBLANK_HAVE_VCOUNT | FB_VBLANK_HAVE_VSYNC; trace = read_reg(0x028c0) >> 16; -- 1.7.4.4