tun: Use memdup_user() rather than duplicating its implementation

Reuse existing functionality from memdup_user() instead of keeping
duplicate source code.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Markus Elfring 2016-08-20 08:54:15 +02:00 committed by David S. Miller
parent 4825a4e42c
commit 28e8190d2f
1 changed files with 3 additions and 8 deletions

View File

@ -731,14 +731,9 @@ static int update_filter(struct tap_filter *filter, void __user *arg)
}
alen = ETH_ALEN * uf.count;
addr = kmalloc(alen, GFP_KERNEL);
if (!addr)
return -ENOMEM;
if (copy_from_user(addr, arg + sizeof(uf), alen)) {
err = -EFAULT;
goto done;
}
addr = memdup_user(arg + sizeof(uf), alen);
if (IS_ERR(addr))
return PTR_ERR(addr);
/* The filter is updated without holding any locks. Which is
* perfectly safe. We disable it first and in the worst