From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754852Ab2CLAxn (ORCPT ); Sun, 11 Mar 2012 20:53:43 -0400 Received: from 1wt.eu ([62.212.114.60]:63113 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754619Ab2CLAs4 (ORCPT ); Sun, 11 Mar 2012 20:48:56 -0400 Message-Id: <20120312004411.845404654@1wt.eu> User-Agent: quilt/0.48-1 Date: Mon, 12 Mar 2012 01:44:24 +0100 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Dan Carpenter , Jens Axboe , Greg Kroah-Hartman Subject: [ 13/13] cdrom: use copy_to_user() without the underscores In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.27-longterm review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter commit 822bfa51ce44f2c63c300fdb76dc99c4d5a5ca9f upstream. "nframes" comes from the user and "nframes * CD_FRAMESIZE_RAW" can wrap on 32 bit systems. That would have been ok if we used the same wrapped value for the copy, but we use a shifted value. We should just use the checked version of copy_to_user() because it's not going to make a difference to the speed. Signed-off-by: Dan Carpenter Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman --- drivers/cdrom/cdrom.c | 8 +------- 1 files changed, 1 insertions(+), 7 deletions(-) diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c index 59cccc9..a4592ec 100644 --- a/drivers/cdrom/cdrom.c +++ b/drivers/cdrom/cdrom.c @@ -2057,11 +2057,6 @@ static int cdrom_read_cdda_old(struct cdrom_device_info *cdi, __u8 __user *ubuf, if (!nr) return -ENOMEM; - if (!access_ok(VERIFY_WRITE, ubuf, nframes * CD_FRAMESIZE_RAW)) { - ret = -EFAULT; - goto out; - } - cgc.data_direction = CGC_DATA_READ; while (nframes > 0) { if (nr > nframes) @@ -2070,7 +2065,7 @@ static int cdrom_read_cdda_old(struct cdrom_device_info *cdi, __u8 __user *ubuf, ret = cdrom_read_block(cdi, &cgc, lba, nr, 1, CD_FRAMESIZE_RAW); if (ret) break; - if (__copy_to_user(ubuf, cgc.buffer, CD_FRAMESIZE_RAW * nr)) { + if (copy_to_user(ubuf, cgc.buffer, CD_FRAMESIZE_RAW * nr)) { ret = -EFAULT; break; } @@ -2078,7 +2073,6 @@ static int cdrom_read_cdda_old(struct cdrom_device_info *cdi, __u8 __user *ubuf, nframes -= nr; lba += nr; } -out: kfree(cgc.buffer); return ret; } -- 1.7.2.1.45.g54fbc