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Subject[ 72/72] cdrom: use copy_to_user() without the underscores
3.2-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@oracle.com>

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 <dan.carpenter@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/cdrom/cdrom.c | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)

--- a/drivers/cdrom/cdrom.c
+++ b/drivers/cdrom/cdrom.c
@@ -2120,11 +2120,6 @@ static int cdrom_read_cdda_old(struct cd
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)
@@ -2133,7 +2128,7 @@ static int cdrom_read_cdda_old(struct cd
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;
}
@@ -2141,7 +2136,6 @@ static int cdrom_read_cdda_old(struct cd
nframes -= nr;
lba += nr;
}
-out:
kfree(cgc.buffer);
return ret;
}



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