From: Markus Elfring <elfring@users.sourceforge.net>
Date: Sat, 20 Aug 2016 05:50:09 +0000 (+0200)
Subject: mlx5/core: Use memdup_user() rather than duplicating its implementation
X-Git-Tag: v4.9-rc1~127^2~416
X-Git-Url: http://git.cascardo.info/?a=commitdiff_plain;h=6f0b826da4a33e83501d6c1dc977afa0f5f7166f;hp=b9a24bb76bf611a5268ceffe04219e6ad264559b;p=cascardo%2Flinux.git

mlx5/core: 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.

* Return directly if this copy operation failed.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c
index d6e2a1cae19a..bf682252130b 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/cmd.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/cmd.c
@@ -1015,7 +1015,6 @@ static ssize_t data_write(struct file *filp, const char __user *buf,
 	struct mlx5_core_dev *dev = filp->private_data;
 	struct mlx5_cmd_debug *dbg = &dev->cmd.dbg;
 	void *ptr;
-	int err;
 
 	if (*pos != 0)
 		return -EINVAL;
@@ -1023,25 +1022,15 @@ static ssize_t data_write(struct file *filp, const char __user *buf,
 	kfree(dbg->in_msg);
 	dbg->in_msg = NULL;
 	dbg->inlen = 0;
-
-	ptr = kzalloc(count, GFP_KERNEL);
-	if (!ptr)
-		return -ENOMEM;
-
-	if (copy_from_user(ptr, buf, count)) {
-		err = -EFAULT;
-		goto out;
-	}
+	ptr = memdup_user(buf, count);
+	if (IS_ERR(ptr))
+		return PTR_ERR(ptr);
 	dbg->in_msg = ptr;
 	dbg->inlen = count;
 
 	*pos = count;
 
 	return count;
-
-out:
-	kfree(ptr);
-	return err;
 }
 
 static ssize_t data_read(struct file *filp, char __user *buf, size_t count,