[ 72/72] cdrom: use copy_to_user() without the underscores
From: Greg KH <gregkh@linuxfoundation.org>
Date: 2012-02-28 01:16:04
Also in:
lkml
3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter <redacted> 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 <redacted> 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; }