[PATCH v6 0/2] net/mlx5: Fix NULL dereference and memory leak in ttc_table creation

[PATCH v6 0/2] net/mlx5: Fix NULL dereference and memory leak in ttc_table creation

[Henry Martin]

This patch series addresses two issues in the
mlx5_create_inner_ttc_table() and mlx5_create_ttc_table() functions:

1. A potential NULL pointer dereference if mlx5_get_flow_namespace()
returns NULL.

2. A memory leak in the error path when ttc_type is invalid (default:
switch case).

Henry Martin (2):
  net/mlx5: Fix null-ptr-deref in mlx5_create_{inner_,}ttc_table()
  net/mlx5: Move ttc allocation after switch case to prevent leaks

 .../ethernet/mellanox/mlx5/core/lib/fs_ttc.c  | 26 +++++++++++++------
 1 file changed, 18 insertions(+), 8 deletions(-)

-- 
2.34.1

[PATCH v6 1/2] net/mlx5: Fix null-ptr-deref in mlx5_create_{inner_,}ttc_table()

[Henry Martin]

Add NULL check for mlx5_get_flow_namespace() returns in
mlx5_create_inner_ttc_table() and mlx5_create_ttc_table() to prevent
NULL pointer dereference.

Fixes: 137f3d50ad2a ("net/mlx5: Support matching on l4_type for ttc_table")
Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c
index eb3bd9c7f66e..066121fed718 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c
@@ -655,6 +655,11 @@ struct mlx5_ttc_table *mlx5_create_inner_ttc_table(struct mlx5_core_dev *dev,
 	}
 
 	ns = mlx5_get_flow_namespace(dev, params->ns_type);
+	if (!ns) {
+		kvfree(ttc);
+		return ERR_PTR(-EOPNOTSUPP);
+	}
+
 	groups = use_l4_type ? &inner_ttc_groups[TTC_GROUPS_USE_L4_TYPE] :
 			       &inner_ttc_groups[TTC_GROUPS_DEFAULT];
 
@@ -728,6 +733,11 @@ struct mlx5_ttc_table *mlx5_create_ttc_table(struct mlx5_core_dev *dev,
 	}
 
 	ns = mlx5_get_flow_namespace(dev, params->ns_type);
+	if (!ns) {
+		kvfree(ttc);
+		return ERR_PTR(-EOPNOTSUPP);
+	}
+
 	groups = use_l4_type ? &ttc_groups[TTC_GROUPS_USE_L4_TYPE] :
 			       &ttc_groups[TTC_GROUPS_DEFAULT];
 
-- 
2.34.1

[PATCH v6 2/2] net/mlx5: Move ttc allocation after switch case to prevent leaks

[Henry Martin]

Relocate the memory allocation for ttc table after the switch statement
that validates params->ns_type in both mlx5_create_inner_ttc_table() and
mlx5_create_ttc_table(). This ensures memory is only allocated after
confirming valid input, eliminating potential memory leaks when invalid
ns_type cases occur.

Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
---
 .../net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c
index 066121fed718..513dafd5ebf2 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c
@@ -637,10 +637,6 @@ struct mlx5_ttc_table *mlx5_create_inner_ttc_table(struct mlx5_core_dev *dev,
 	bool use_l4_type;
 	int err;
 
-	ttc = kvzalloc(sizeof(*ttc), GFP_KERNEL);
-	if (!ttc)
-		return ERR_PTR(-ENOMEM);
-
 	switch (params->ns_type) {
 	case MLX5_FLOW_NAMESPACE_PORT_SEL:
 		use_l4_type = MLX5_CAP_GEN_2(dev, pcc_ifa2) &&
@@ -654,6 +650,10 @@ struct mlx5_ttc_table *mlx5_create_inner_ttc_table(struct mlx5_core_dev *dev,
 		return ERR_PTR(-EINVAL);
 	}
 
+	ttc = kvzalloc(sizeof(*ttc), GFP_KERNEL);
+	if (!ttc)
+		return ERR_PTR(-ENOMEM);
+
 	ns = mlx5_get_flow_namespace(dev, params->ns_type);
 	if (!ns) {
 		kvfree(ttc);
@@ -715,10 +715,6 @@ struct mlx5_ttc_table *mlx5_create_ttc_table(struct mlx5_core_dev *dev,
 	bool use_l4_type;
 	int err;
 
-	ttc = kvzalloc(sizeof(*ttc), GFP_KERNEL);
-	if (!ttc)
-		return ERR_PTR(-ENOMEM);
-
 	switch (params->ns_type) {
 	case MLX5_FLOW_NAMESPACE_PORT_SEL:
 		use_l4_type = MLX5_CAP_GEN_2(dev, pcc_ifa2) &&
@@ -732,6 +728,10 @@ struct mlx5_ttc_table *mlx5_create_ttc_table(struct mlx5_core_dev *dev,
 		return ERR_PTR(-EINVAL);
 	}
 
+	ttc = kvzalloc(sizeof(*ttc), GFP_KERNEL);
+	if (!ttc)
+		return ERR_PTR(-ENOMEM);
+
 	ns = mlx5_get_flow_namespace(dev, params->ns_type);
 	if (!ns) {
 		kvfree(ttc);
-- 
2.34.1

Re: [PATCH v6 2/2] net/mlx5: Move ttc allocation after switch case to prevent leaks

[Michal Swiatkowski]

On Wed, Apr 16, 2025 at 05:22:43PM +0800, Henry Martin wrote:
> Relocate the memory allocation for ttc table after the switch statement
> that validates params->ns_type in both mlx5_create_inner_ttc_table() and
> mlx5_create_ttc_table(). This ensures memory is only allocated after
> confirming valid input, eliminating potential memory leaks when invalid
> ns_type cases occur.
> 
> Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
> ---
>  .../net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c | 16 ++++++++--------
>  1 file changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c
> index 066121fed718..513dafd5ebf2 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c
> @@ -637,10 +637,6 @@ struct mlx5_ttc_table *mlx5_create_inner_ttc_table(struct mlx5_core_dev *dev,
>  	bool use_l4_type;
>  	int err;
>  
> -	ttc = kvzalloc(sizeof(*ttc), GFP_KERNEL);
> -	if (!ttc)
> -		return ERR_PTR(-ENOMEM);
> -
>  	switch (params->ns_type) {
>  	case MLX5_FLOW_NAMESPACE_PORT_SEL:
>  		use_l4_type = MLX5_CAP_GEN_2(dev, pcc_ifa2) &&
> @@ -654,6 +650,10 @@ struct mlx5_ttc_table *mlx5_create_inner_ttc_table(struct mlx5_core_dev *dev,
>  		return ERR_PTR(-EINVAL);
>  	}
>  
> +	ttc = kvzalloc(sizeof(*ttc), GFP_KERNEL);
> +	if (!ttc)
> +		return ERR_PTR(-ENOMEM);
> +
>  	ns = mlx5_get_flow_namespace(dev, params->ns_type);
>  	if (!ns) {
>  		kvfree(ttc);
> @@ -715,10 +715,6 @@ struct mlx5_ttc_table *mlx5_create_ttc_table(struct mlx5_core_dev *dev,
>  	bool use_l4_type;
>  	int err;
>  
> -	ttc = kvzalloc(sizeof(*ttc), GFP_KERNEL);
> -	if (!ttc)
> -		return ERR_PTR(-ENOMEM);
> -
>  	switch (params->ns_type) {
>  	case MLX5_FLOW_NAMESPACE_PORT_SEL:
>  		use_l4_type = MLX5_CAP_GEN_2(dev, pcc_ifa2) &&
> @@ -732,6 +728,10 @@ struct mlx5_ttc_table *mlx5_create_ttc_table(struct mlx5_core_dev *dev,
>  		return ERR_PTR(-EINVAL);
>  	}
>  
> +	ttc = kvzalloc(sizeof(*ttc), GFP_KERNEL);
> +	if (!ttc)
> +		return ERR_PTR(-ENOMEM);
> +
>  	ns = mlx5_get_flow_namespace(dev, params->ns_type);
>  	if (!ns) {
>  		kvfree(ttc);

Thanks for fixing
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>

> -- 
> 2.34.1
> 

Re: [PATCH v6 2/2] net/mlx5: Move ttc allocation after switch case to prevent leaks

[Mark Bloch]

On 16/04/2025 12:22, Henry Martin wrote:
> Relocate the memory allocation for ttc table after the switch statement
> that validates params->ns_type in both mlx5_create_inner_ttc_table() and
> mlx5_create_ttc_table(). This ensures memory is only allocated after
> confirming valid input, eliminating potential memory leaks when invalid
> ns_type cases occur.
> 
> Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
> ---
>  .../net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c | 16 ++++++++--------
>  1 file changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c b/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c
> index 066121fed718..513dafd5ebf2 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/lib/fs_ttc.c
> @@ -637,10 +637,6 @@ struct mlx5_ttc_table *mlx5_create_inner_ttc_table(struct mlx5_core_dev *dev,
>  	bool use_l4_type;
>  	int err;
>  
> -	ttc = kvzalloc(sizeof(*ttc), GFP_KERNEL);
> -	if (!ttc)
> -		return ERR_PTR(-ENOMEM);
> -
>  	switch (params->ns_type) {
>  	case MLX5_FLOW_NAMESPACE_PORT_SEL:
>  		use_l4_type = MLX5_CAP_GEN_2(dev, pcc_ifa2) &&
> @@ -654,6 +650,10 @@ struct mlx5_ttc_table *mlx5_create_inner_ttc_table(struct mlx5_core_dev *dev,
>  		return ERR_PTR(-EINVAL);
>  	}
>  
> +	ttc = kvzalloc(sizeof(*ttc), GFP_KERNEL);
> +	if (!ttc)
> +		return ERR_PTR(-ENOMEM);
> +
>  	ns = mlx5_get_flow_namespace(dev, params->ns_type);
>  	if (!ns) {
>  		kvfree(ttc);
> @@ -715,10 +715,6 @@ struct mlx5_ttc_table *mlx5_create_ttc_table(struct mlx5_core_dev *dev,
>  	bool use_l4_type;
>  	int err;
>  
> -	ttc = kvzalloc(sizeof(*ttc), GFP_KERNEL);
> -	if (!ttc)
> -		return ERR_PTR(-ENOMEM);
> -
>  	switch (params->ns_type) {
>  	case MLX5_FLOW_NAMESPACE_PORT_SEL:
>  		use_l4_type = MLX5_CAP_GEN_2(dev, pcc_ifa2) &&
> @@ -732,6 +728,10 @@ struct mlx5_ttc_table *mlx5_create_ttc_table(struct mlx5_core_dev *dev,
>  		return ERR_PTR(-EINVAL);
>  	}
>  
> +	ttc = kvzalloc(sizeof(*ttc), GFP_KERNEL);
> +	if (!ttc)
> +		return ERR_PTR(-ENOMEM);
> +
>  	ns = mlx5_get_flow_namespace(dev, params->ns_type);
>  	if (!ns) {
>  		kvfree(ttc);

Reviewed-by: Mark Bloch <mbloch@nvidia.com>

Mark

Re: [PATCH v6 0/2] net/mlx5: Fix NULL dereference and memory leak in ttc_table creation

[Markus Elfring]

> This patch series addresses two issues in …

It would have been helpful to extend patch version descriptions accordingly.
https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?h=v6.15-rc2#n310

Regards,
Markus

Re: [PATCH v6 1/2] net/mlx5: Fix null-ptr-deref in mlx5_create_{inner_,}ttc_table()

[Markus Elfring]

> Add NULL check for mlx5_get_flow_namespace() returns in
> mlx5_create_inner_ttc_table() and mlx5_create_ttc_table() to prevent
> NULL pointer dereference.

* Can an other summary phrase variant become more desirable accordingly?

* Please avoid duplicate source code.


Regards,
Markus

Re: [PATCH v6 2/2] net/mlx5: Move ttc allocation after switch case to prevent leaks

[Jakub Kicinski]

On Wed, 16 Apr 2025 15:02:13 +0300 Mark Bloch wrote:
> On 16/04/2025 12:22, Henry Martin wrote:
> > Relocate the memory allocation for ttc table after the switch statement
> > that validates params->ns_type in both mlx5_create_inner_ttc_table() and
> > mlx5_create_ttc_table(). This ensures memory is only allocated after
> > confirming valid input, eliminating potential memory leaks when invalid
> > ns_type cases occur.
> 
> Reviewed-by: Mark Bloch <mbloch@nvidia.com>

A bit hard to see from the context but I'm guessing this fixes 
a memory leak? We need a Fixes tag..

reminder: please trim your replies
-- 
pw-bot: cr

Re: [PATCH v6 2/2] net/mlx5: Move ttc allocation after switch case to prevent leaks

[henry martin]

> A bit hard to see from the context but I'm guessing this fixes
> a memory leak? We need a Fixes tag..

Thanks for the reminder. I've added the Fixes tag in v7.

Regards,
Henry