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Subject[ 13/13] cdrom: use copy_to_user() without the underscores
2.6.27-longterm 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 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




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