[PATCH] net/mlx5e: TC, Fix use after free in mlx5e_clone_flow_attr_for_post_act()

[PATCH] net/mlx5e: TC, Fix use after free in mlx5e_clone_flow_attr_for_post_act()

[Dan Carpenter]

This returns freed memory leading to a use after free.  It's supposed to
return NULL.

Fixes: 8300f225268b ("net/mlx5e: Create new flow attr for multi table actions")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
This goes through Saeed's tree not the net tree.

 drivers/net/ethernet/mellanox/mlx5/core/en_tc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
index 76a015dfc5fc..c0776a4a3845 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
@@ -3398,7 +3398,7 @@ mlx5e_clone_flow_attr_for_post_act(struct mlx5_flow_attr *attr,
 	if (!attr2 || !parse_attr) {
 		kvfree(parse_attr);
 		kfree(attr2);
-		return attr2;
+		return NULL;
 	}
 
 	memcpy(attr2, attr, attr_sz);
-- 
2.20.1

Re: [PATCH] net/mlx5e: TC, Fix use after free in mlx5e_clone_flow_attr_for_post_act()

[Roi Dayan]

On 2022-02-24 4:53 PM, Dan Carpenter wrote:
> This returns freed memory leading to a use after free.  It's supposed to
> return NULL.
> 
> Fixes: 8300f225268b ("net/mlx5e: Create new flow attr for multi table actions")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> ---
> This goes through Saeed's tree not the net tree.
> 
>   drivers/net/ethernet/mellanox/mlx5/core/en_tc.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
> index 76a015dfc5fc..c0776a4a3845 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
> @@ -3398,7 +3398,7 @@ mlx5e_clone_flow_attr_for_post_act(struct mlx5_flow_attr *attr,
>   	if (!attr2 || !parse_attr) {
>   		kvfree(parse_attr);
>   		kfree(attr2);
> -		return attr2;
> +		return NULL;
>   	}
>   
>   	memcpy(attr2, attr, attr_sz);

hi, I noticed your fix now and already reviewed same fix from Colin

https://patchwork.kernel.org/project/netdevbpf/patch/20220224221525.147744-1-colin.i.king@gmail.com/

so just need to take either one.
thanks

Reviewed-by: Roi Dayan <roid@nvidia.com>

Re: [PATCH] net/mlx5e: TC, Fix use after free in mlx5e_clone_flow_attr_for_post_act()

[Saeed Mahameed]

On 25 Feb 14:18, Roi Dayan wrote:
>
>
>On 2022-02-24 4:53 PM, Dan Carpenter wrote:
>>This returns freed memory leading to a use after free.  It's supposed to
>>return NULL.
>>
>>Fixes: 8300f225268b ("net/mlx5e: Create new flow attr for multi table actions")
>>Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
>>---
>>This goes through Saeed's tree not the net tree.
>>
>>  drivers/net/ethernet/mellanox/mlx5/core/en_tc.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>>diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
>>index 76a015dfc5fc..c0776a4a3845 100644
>>--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
>>+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
>>@@ -3398,7 +3398,7 @@ mlx5e_clone_flow_attr_for_post_act(struct mlx5_flow_attr *attr,
>>  	if (!attr2 || !parse_attr) {
>>  		kvfree(parse_attr);
>>  		kfree(attr2);
>>-		return attr2;
>>+		return NULL;
>>  	}
>>  	memcpy(attr2, attr, attr_sz);
>
>hi, I noticed your fix now and already reviewed same fix from Colin
>
>https://patchwork.kernel.org/project/netdevbpf/patch/20220224221525.147744-1-colin.i.king@gmail.com/
>
>so just need to take either one.
>thanks
>

Ok this one arrived first, will take this one :).
applied to net-next-mlx5.

>Reviewed-by: Roi Dayan <roid@nvidia.com>