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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/net/wan/sdla.c | 11 +++--------
1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/drivers/net/wan/sdla.c b/drivers/net/wan/sdla.c
index 43ae6f4..258efc2 100644
--- a/drivers/net/wan/sdla.c
+++ b/drivers/net/wan/sdla.c
@@ -1211,14 +1211,9 @@ static int sdla_xfer(struct net_device *dev, struct sdla_mem __user *info, int r
}
else
{
- temp = kmalloc(mem.len, GFP_KERNEL);
- if (!temp)
- return(-ENOMEM);
- if(copy_from_user(temp, mem.data, mem.len))
- {
- kfree(temp);
- return -EFAULT;
- }
+ temp = memdup_user(mem.data, mem.len);
+ if (IS_ERR(temp))
+ return PTR_ERR(temp);
sdla_write(dev, mem.addr, temp, mem.len);
kfree(temp);
}
--
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Prev: [PATCH 18/27] drivers/message/i2o/i2o_config.c: Use memdup_user
Next: [PATCH 25/27] drivers/usb/gadget: Use memdup_user