Prev: [PATCH 7/27] drivers/net/wan: Use memdup_user
Next: [PATCH 13/27] fs/autofs4: Use memdup_user
From: Julia Lawall on 22 May 2010 04:30
From: Julia Lawall <julia(a)diku.dk>

Use memdup_user when user data is immediately copied into the
allocated region.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression from,to,size,flag;
position p;
identifier l1,l2;
@@

- to = \(kmalloc@p\|kzalloc@p\)(size,flag);
+ to = memdup_user(from,size);
if (
- to==NULL
+ IS_ERR(to)
|| ...) {
<+... when != goto l1;
- -ENOMEM
+ PTR_ERR(to)
...+>
}
- if (copy_from_user(to, from, size) != 0) {
- <+... when != goto l2;
- -EFAULT
- ...+>
- }
// </smpl>

Signed-off-by: Julia Lawall <julia(a)diku.dk>

---
drivers/usb/gadget/inode.c | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/usb/gadget/inode.c b/drivers/usb/gadget/inode.c
index de8a838..63fc171 100644
--- a/drivers/usb/gadget/inode.c
+++ b/drivers/usb/gadget/inode.c
@@ -1867,13 +1867,9 @@ dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
buf += 4;
length -= 4;

- kbuf = kmalloc (length, GFP_KERNEL);
- if (!kbuf)
- return -ENOMEM;
- if (copy_from_user (kbuf, buf, length)) {
- kfree (kbuf);
- return -EFAULT;
- }
+ kbuf = memdup_user(buf, length);
+ if (IS_ERR(kbuf))
+ return PTR_ERR(kbuf);

spin_lock_irq (&dev->lock);
value = -EINVAL;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
 | 
Pages: 1
Prev: [PATCH 7/27] drivers/net/wan: Use memdup_user
Next: [PATCH 13/27] fs/autofs4: Use memdup_user