Re: [PATCH] ima: use memdup_user_nul

From: Mimi Zohar
Date: Mon May 08 2017 - 11:45:48 EST


On Sat, 2017-05-06 at 23:40 +0800, Geliang Tang wrote:
> Use memdup_user_nul() helper instead of open-coding to simplify the
> code.
>
> Signed-off-by: Geliang Tang <geliangtang@xxxxxxxxx>

Thanks, this patch will be queued.

Mimi

> ---
> security/integrity/ima/ima_fs.c | 13 ++++---------
> 1 file changed, 4 insertions(+), 9 deletions(-)
>
> diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
> index ca303e5..ad491c5 100644
> --- a/security/integrity/ima/ima_fs.c
> +++ b/security/integrity/ima/ima_fs.c
> @@ -323,16 +323,11 @@ static ssize_t ima_write_policy(struct file *file, const char __user *buf,
> if (*ppos != 0)
> goto out;
>
> - result = -ENOMEM;
> - data = kmalloc(datalen + 1, GFP_KERNEL);
> - if (!data)
> + data = memdup_user_nul(buf, datalen);
> + if (IS_ERR(data)) {
> + result = PTR_ERR(data);
> goto out;
> -
> - *(data + datalen) = '\0';
> -
> - result = -EFAULT;
> - if (copy_from_user(data, buf, datalen))
> - goto out_free;
> + }
>
> result = mutex_lock_interruptible(&ima_write_mutex);
> if (result < 0)