1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
|
From c1dd346c39c2a7d3ca7b9670e9504ae19d4e927a Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Mon, 6 Feb 2012 10:20:45 +0100
Subject: [PATCH 72/73] 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 <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 cedb231..2678b6f 100644
--- a/drivers/cdrom/cdrom.c
+++ b/drivers/cdrom/cdrom.c
@@ -2120,11 +2120,6 @@ 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)
@@ -2133,7 +2128,7 @@ 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;
}
@@ -2141,7 +2136,6 @@ static int cdrom_read_cdda_old(struct cdrom_device_info *cdi, __u8 __user *ubuf,
nframes -= nr;
lba += nr;
}
-out:
kfree(cgc.buffer);
return ret;
}
--
1.7.7.4
|
