From 6b06abace47c8ac0afb6cac21a133b85cd296e50 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Mon, 6 Feb 2012 10:20:45 +0100 Subject: [PATCH] cdrom: use copy_to_user() without the underscores 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 file changed, 1 insertion(+), 7 deletions(-) diff --git a/drivers/cdrom/cdrom.c b/drivers/cdrom/cdrom.c index b693cbdb421f..cc6471aa9f46 100644 --- a/drivers/cdrom/cdrom.c +++ b/drivers/cdrom/cdrom.c @@ -2114,11 +2114,6 @@ 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) @@ -2127,7 +2122,7 @@ 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; } @@ -2135,7 +2130,6 @@ static int cdrom_read_cdda_old(struct cdrom_device_info *cdi, __u8 __user *ubuf, nframes -= nr; lba += nr; } -out: kfree(cgc.buffer); return ret; } -- 2.39.5