From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754080Ab1ABHXu (ORCPT ); Sun, 2 Jan 2011 02:23:50 -0500 Received: from mail.windriver.com ([147.11.1.11]:35801 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753966Ab1ABHXo (ORCPT ); Sun, 2 Jan 2011 02:23:44 -0500 From: Paul Gortmaker To: stable@kernel.org, linux-kernel@vger.kernel.org Cc: stable-review@kernel.org, Dan Rosenberg , Dan Rosenberg , Thomas Winischhofer , Andrew Morton , Linus Torvalds , Paul Gortmaker Subject: [34-longterm 133/260] drivers/video/sis/sis_main.c: prevent reading uninitialized stack memory Date: Sun, 2 Jan 2011 02:17:09 -0500 Message-Id: <1293952756-15010-134-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.7.3.3 In-Reply-To: <1293952756-15010-1-git-send-email-paul.gortmaker@windriver.com> References: <1293952756-15010-1-git-send-email-paul.gortmaker@windriver.com> X-OriginalArrivalTime: 02 Jan 2011 07:22:36.0009 (UTC) FILETIME=[D43BE590:01CBAA4D] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dan Rosenberg commit fd02db9de73faebc51240619c7c7f99bee9f65c7 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 Cc: Thomas Winischhofer Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Paul Gortmaker --- drivers/video/sis/sis_main.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/drivers/video/sis/sis_main.c b/drivers/video/sis/sis_main.c index a531a0f..900b3a0 100644 --- a/drivers/video/sis/sis_main.c +++ b/drivers/video/sis/sis_main.c @@ -1701,6 +1701,9 @@ static int sisfb_ioctl(struct fb_info *info, unsigned int cmd, break; case FBIOGET_VBLANK: + + memset(&sisvbblank, 0, sizeof(struct fb_vblank)); + sisvbblank.count = 0; sisvbblank.flags = sisfb_setupvbblankflags(ivideo, &sisvbblank.vcount, &sisvbblank.hcount); -- 1.7.3.3