From: Dan Carpenter Date: Mon, 6 Feb 2012 09:20:45 +0000 (+0100) Subject: cdrom: use copy_to_user() without the underscores X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=822bfa51ce44f2c63c300fdb76dc99c4d5a5ca9f;p=linux-beck.git cdrom: use copy_to_user() without the underscores "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. Cc: stable@vger.kernel.com Signed-off-by: Dan Carpenter Signed-off-by: Jens Axboe --- diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c index 55eaf474d32c..8fefe59f52a7 100644 --- a/drivers/cdrom/cdrom.c +++ b/drivers/cdrom/cdrom.c @@ -2119,11 +2119,6 @@ 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) @@ -2132,7 +2127,7 @@ 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; } @@ -2140,7 +2135,6 @@ static int cdrom_read_cdda_old(struct cdrom_device_info *cdi, __u8 __user *ubuf, nframes -= nr; lba += nr; } -out: kfree(cgc.buffer); return ret; }