Re: [PATCH v2] net/mlx4_en: Fix an error handling path in 'mlx4_en_init_netdev()'

[David Miller]

From: Christophe JAILLET 
Date: Thu, 10 May 2018 09:06:04 +0200

> If an error occurs, 'mlx4_en_destroy_netdev()' is called.
> It then calls 'mlx4_en_free_resources()' which does the needed resources
> cleanup.
> 
> So, doing some explicit kfree in the error handling path would lead to
> some double kfree.
> 
> Simplify code to avoid such a case.
> 
> Fixes: 67f8b1dcb9ee ("net/mlx4_en: Refactor the XDP forwarding rings scheme")
> Signed-off-by: Christophe JAILLET 

Applied and queued up for -stable, thanks.

Re: [PATCH v2] net/mlx4_en: Fix an error handling path in 'mlx4_en_init_netdev()'

[David Miller]

From: Christophe JAILLET 
Date: Thu, 10 May 2018 09:06:04 +0200

> If an error occurs, 'mlx4_en_destroy_netdev()' is called.
> It then calls 'mlx4_en_free_resources()' which does the needed resources
> cleanup.
> 
> So, doing some explicit kfree in the error handling path would lead to
> some double kfree.
> 
> Simplify code to avoid such a case.
> 
> Fixes: 67f8b1dcb9ee ("net/mlx4_en: Refactor the XDP forwarding rings scheme")
> Signed-off-by: Christophe JAILLET 

Applied and queued up for -stable, thanks.

Re: [PATCH v2] net/mlx4_en: Fix an error handling path in 'mlx4_en_init_netdev()'

[Tariq Toukan]

On 10/05/2018 10:06 AM, Christophe JAILLET wrote:

If an error occurs, 'mlx4_en_destroy_netdev()' is called.
It then calls 'mlx4_en_free_resources()' which does the needed resources
cleanup.

So, doing some explicit kfree in the error handling path would lead to
some double kfree.

Simplify code to avoid such a case.

Fixes: 67f8b1dcb9ee ("net/mlx4_en: Refactor the XDP forwarding rings scheme")
Signed-off-by: Christophe JAILLET 
---
v1 -> v2 : rewrite the fix as explained by Tariq Toukan
(this 2nd version may have been posted twice, once without the
v2 tag. PLease ignore the first one)
---

  drivers/net/ethernet/mellanox/mlx4/en_netdev.c | 8 +---
  1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c 
b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index e0adac4a9a19..9670b33fc9b1 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -3324,12 +3324,11 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int 
port,
   MAX_TX_RINGS, GFP_KERNEL);
if (!priv->tx_ring[t]) {
err = -ENOMEM;
-   goto err_free_tx;
+   goto out;
}
priv->tx_cq[t] = kzalloc(sizeof(struct mlx4_en_cq *) *
 MAX_TX_RINGS, GFP_KERNEL);
if (!priv->tx_cq[t]) {
-   kfree(priv->tx_ring[t]);
err = -ENOMEM;
goto out;
}
@@ -3582,11 +3581,6 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int 
port,
  
  	return 0;
  
-err_free_tx:

-   while (t--) {
-   kfree(priv->tx_ring[t]);
-   kfree(priv->tx_cq[t]);
-   }
  out:
mlx4_en_destroy_netdev(dev);
return err;



Reviewed-by: Tariq Toukan 

Thanks Christophe.

Re: [PATCH v2] net/mlx4_en: Fix an error handling path in 'mlx4_en_init_netdev()'

[Tariq Toukan]

On 10/05/2018 10:06 AM, Christophe JAILLET wrote:

If an error occurs, 'mlx4_en_destroy_netdev()' is called.
It then calls 'mlx4_en_free_resources()' which does the needed resources
cleanup.

So, doing some explicit kfree in the error handling path would lead to
some double kfree.

Simplify code to avoid such a case.

Fixes: 67f8b1dcb9ee ("net/mlx4_en: Refactor the XDP forwarding rings scheme")
Signed-off-by: Christophe JAILLET 
---
v1 -> v2 : rewrite the fix as explained by Tariq Toukan
(this 2nd version may have been posted twice, once without the
v2 tag. PLease ignore the first one)
---

  drivers/net/ethernet/mellanox/mlx4/en_netdev.c | 8 +---
  1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c 
b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index e0adac4a9a19..9670b33fc9b1 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -3324,12 +3324,11 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int 
port,
   MAX_TX_RINGS, GFP_KERNEL);
if (!priv->tx_ring[t]) {
err = -ENOMEM;
-   goto err_free_tx;
+   goto out;
}
priv->tx_cq[t] = kzalloc(sizeof(struct mlx4_en_cq *) *
 MAX_TX_RINGS, GFP_KERNEL);
if (!priv->tx_cq[t]) {
-   kfree(priv->tx_ring[t]);
err = -ENOMEM;
goto out;
}
@@ -3582,11 +3581,6 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int 
port,
  
  	return 0;
  
-err_free_tx:

-   while (t--) {
-   kfree(priv->tx_ring[t]);
-   kfree(priv->tx_cq[t]);
-   }
  out:
mlx4_en_destroy_netdev(dev);
return err;



Reviewed-by: Tariq Toukan 

Thanks Christophe.

[PATCH v2] net/mlx4_en: Fix an error handling path in 'mlx4_en_init_netdev()'

[Christophe JAILLET]

If an error occurs, 'mlx4_en_destroy_netdev()' is called.
It then calls 'mlx4_en_free_resources()' which does the needed resources
cleanup.

So, doing some explicit kfree in the error handling path would lead to
some double kfree.

Simplify code to avoid such a case.

Fixes: 67f8b1dcb9ee ("net/mlx4_en: Refactor the XDP forwarding rings scheme")
Signed-off-by: Christophe JAILLET 
---
v1 -> v2 : rewrite the fix as explained by Tariq Toukan
   (this 2nd version may have been posted twice, once without the
   v2 tag. PLease ignore the first one)
---

 drivers/net/ethernet/mellanox/mlx4/en_netdev.c | 8 +---
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c 
b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index e0adac4a9a19..9670b33fc9b1 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -3324,12 +3324,11 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int 
port,
   MAX_TX_RINGS, GFP_KERNEL);
if (!priv->tx_ring[t]) {
err = -ENOMEM;
-   goto err_free_tx;
+   goto out;
}
priv->tx_cq[t] = kzalloc(sizeof(struct mlx4_en_cq *) *
 MAX_TX_RINGS, GFP_KERNEL);
if (!priv->tx_cq[t]) {
-   kfree(priv->tx_ring[t]);
err = -ENOMEM;
goto out;
}
@@ -3582,11 +3581,6 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int 
port,
 
return 0;
 
-err_free_tx:
-   while (t--) {
-   kfree(priv->tx_ring[t]);
-   kfree(priv->tx_cq[t]);
-   }
 out:
mlx4_en_destroy_netdev(dev);
return err;
-- 
2.17.0

[PATCH v2] net/mlx4_en: Fix an error handling path in 'mlx4_en_init_netdev()'

[Christophe JAILLET]

If an error occurs, 'mlx4_en_destroy_netdev()' is called.
It then calls 'mlx4_en_free_resources()' which does the needed resources
cleanup.

So, doing some explicit kfree in the error handling path would lead to
some double kfree.

Simplify code to avoid such a case.

Fixes: 67f8b1dcb9ee ("net/mlx4_en: Refactor the XDP forwarding rings scheme")
Signed-off-by: Christophe JAILLET 
---
v1 -> v2 : rewrite the fix as explained by Tariq Toukan
   (this 2nd version may have been posted twice, once without the
   v2 tag. PLease ignore the first one)
---

 drivers/net/ethernet/mellanox/mlx4/en_netdev.c | 8 +---
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c 
b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index e0adac4a9a19..9670b33fc9b1 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -3324,12 +3324,11 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int 
port,
   MAX_TX_RINGS, GFP_KERNEL);
if (!priv->tx_ring[t]) {
err = -ENOMEM;
-   goto err_free_tx;
+   goto out;
}
priv->tx_cq[t] = kzalloc(sizeof(struct mlx4_en_cq *) *
 MAX_TX_RINGS, GFP_KERNEL);
if (!priv->tx_cq[t]) {
-   kfree(priv->tx_ring[t]);
err = -ENOMEM;
goto out;
}
@@ -3582,11 +3581,6 @@ int mlx4_en_init_netdev(struct mlx4_en_dev *mdev, int 
port,
 
return 0;
 
-err_free_tx:
-   while (t--) {
-   kfree(priv->tx_ring[t]);
-   kfree(priv->tx_cq[t]);
-   }
 out:
mlx4_en_destroy_netdev(dev);
return err;
-- 
2.17.0