ima: use memdup_user_nul

Use memdup_user_nul() helper instead of open-coding to simplify the
code.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

1 files changed, 4 insertions, 9 deletions

diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index ca303e5d2b94..ad491c51e833 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)