[PATCH 6/27] drivers/net/cxgb3: Use memdup_user

From: Julia Lawall
Date: Sat May 22 2010 - 04:20:23 EST


From: Julia Lawall <julia@xxxxxxx>

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@xxxxxxx>

---
drivers/net/cxgb3/cxgb3_main.c | 12 +++---------
1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/drivers/net/cxgb3/cxgb3_main.c b/drivers/net/cxgb3/cxgb3_main.c
index e3f1b85..066fd5b 100644
--- a/drivers/net/cxgb3/cxgb3_main.c
+++ b/drivers/net/cxgb3/cxgb3_main.c
@@ -2311,15 +2311,9 @@ static int cxgb_extension_ioctl(struct net_device *dev, void __user *useraddr)
if (copy_from_user(&t, useraddr, sizeof(t)))
return -EFAULT;
/* Check t.len sanity ? */
- fw_data = kmalloc(t.len, GFP_KERNEL);
- if (!fw_data)
- return -ENOMEM;
-
- if (copy_from_user
- (fw_data, useraddr + sizeof(t), t.len)) {
- kfree(fw_data);
- return -EFAULT;
- }
+ fw_data = memdup_user(useraddr + sizeof(t), t.len);
+ if (IS_ERR(fw_data))
+ return PTR_ERR(fw_data);

ret = t3_load_fw(adapter, fw_data, t.len);
kfree(fw_data);
--
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