2023-10-03 23:17:44

by Kees Cook

Subject: [PATCH] net/mlx5: Annotate struct mlx5_flow_handle with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct mlx5_flow_handle.

Cc: Saeed Mahameed <[email protected]>
Cc: Leon Romanovsky <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Eric Dumazet <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: Paolo Abeni <[email protected]>
Cc: [email protected]
Cc: [email protected]
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
Signed-off-by: Kees Cook <[email protected]>
---
drivers/net/ethernet/mellanox/mlx5/core/fs_core.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
index 4aed1768b85f..78eb6b7097e1 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
@@ -181,7 +181,7 @@ struct mlx5_flow_rule {

struct mlx5_flow_handle {
int num_rules;
- struct mlx5_flow_rule *rule[];
+ struct mlx5_flow_rule *rule[] __counted_by(num_rules);
};

/* Type of children is mlx5_flow_group */
--
2.34.1

2023-10-03 23:26:55

by Justin Stitt

Subject: Re: [PATCH] net/mlx5: Annotate struct mlx5_flow_handle with __counted_by

On Tue, Oct 3, 2023 at 4:17 PM Kees Cook <[email protected]> wrote:
>
> Prepare for the coming implementation by GCC and Clang of the __counted_by
> attribute. Flexible array members annotated with __counted_by can have
> their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
> array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> functions).
>
> As found with Coccinelle[1], add __counted_by for struct mlx5_flow_handle.
>
> Cc: Saeed Mahameed <[email protected]>
> Cc: Leon Romanovsky <[email protected]>
> Cc: "David S. Miller" <[email protected]>
> Cc: Eric Dumazet <[email protected]>
> Cc: Jakub Kicinski <[email protected]>
> Cc: Paolo Abeni <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> Signed-off-by: Kees Cook <[email protected]>
> ---
> drivers/net/ethernet/mellanox/mlx5/core/fs_core.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
> index 4aed1768b85f..78eb6b7097e1 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
> @@ -181,7 +181,7 @@ struct mlx5_flow_rule {
>
> struct mlx5_flow_handle {
> int num_rules;
> - struct mlx5_flow_rule *rule[];
> + struct mlx5_flow_rule *rule[] __counted_by(num_rules);
> };

Great patch!

handle->num_rules is properly assigned to before handle->rule
has any accesses.

handle = alloc_handle((dest_num) ? dest_num : 1);

then

static struct mlx5_flow_handle *alloc_handle(int num_rules) {
...
handle->num_rules = num_rules;

then

handle->rule[i] = rule;


Reviewed-by: Justin Stitt <[email protected]>
>
> /* Type of children is mlx5_flow_group */
> --
> 2.34.1
>
>
Thanks
Justin

2023-10-03 23:34:14

by Gustavo A. R. Silva

Subject: Re: [PATCH] net/mlx5: Annotate struct mlx5_flow_handle with __counted_by

On 10/4/23 01:17, Kees Cook wrote:
> Prepare for the coming implementation by GCC and Clang of the __counted_by
> attribute. Flexible array members annotated with __counted_by can have
> their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
> array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> functions).
>
> As found with Coccinelle[1], add __counted_by for struct mlx5_flow_handle.
>
> Cc: Saeed Mahameed <[email protected]>
> Cc: Leon Romanovsky <[email protected]>
> Cc: "David S. Miller" <[email protected]>
> Cc: Eric Dumazet <[email protected]>
> Cc: Jakub Kicinski <[email protected]>
> Cc: Paolo Abeni <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> Signed-off-by: Kees Cook <[email protected]>

Reviewed-by: Gustavo A. R. Silva <[email protected]>

Thanks
--
Gustavo

> ---
> drivers/net/ethernet/mellanox/mlx5/core/fs_core.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
> index 4aed1768b85f..78eb6b7097e1 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_core.h
> @@ -181,7 +181,7 @@ struct mlx5_flow_rule {
>
> struct mlx5_flow_handle {
> int num_rules;
> - struct mlx5_flow_rule *rule[];
> + struct mlx5_flow_rule *rule[] __counted_by(num_rules);
> };
>
> /* Type of children is mlx5_flow_group */

2023-10-04 18:46:43

by Leon Romanovsky

Subject: Re: [PATCH] net/mlx5: Annotate struct mlx5_flow_handle with __counted_by

On Tue, Oct 03, 2023 at 04:17:30PM -0700, Kees Cook wrote:
> Prepare for the coming implementation by GCC and Clang of the __counted_by
> attribute. Flexible array members annotated with __counted_by can have
> their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
> array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> functions).
>
> As found with Coccinelle[1], add __counted_by for struct mlx5_flow_handle.
>
> Cc: Saeed Mahameed <[email protected]>
> Cc: Leon Romanovsky <[email protected]>
> Cc: "David S. Miller" <[email protected]>
> Cc: Eric Dumazet <[email protected]>
> Cc: Jakub Kicinski <[email protected]>
> Cc: Paolo Abeni <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> Signed-off-by: Kees Cook <[email protected]>
> ---
> drivers/net/ethernet/mellanox/mlx5/core/fs_core.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>

Thanks,
Reviewed-by: Leon Romanovsky <[email protected]>

2023-10-12 19:49:48

by Saeed Mahameed

Subject: Re: [PATCH] net/mlx5: Annotate struct mlx5_flow_handle with __counted_by

On 03 Oct 16:17, Kees Cook wrote:
>Prepare for the coming implementation by GCC and Clang of the __counted_by
>attribute. Flexible array members annotated with __counted_by can have
>their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
>array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
>functions).
>
>As found with Coccinelle[1], add __counted_by for struct mlx5_flow_handle.
>
>Cc: Saeed Mahameed <[email protected]>
>Cc: Leon Romanovsky <[email protected]>
>Cc: "David S. Miller" <[email protected]>
>Cc: Eric Dumazet <[email protected]>
>Cc: Jakub Kicinski <[email protected]>
>Cc: Paolo Abeni <[email protected]>
>Cc: [email protected]
>Cc: [email protected]
>Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
>Signed-off-by: Kees Cook <[email protected]>

applied to net-next-mlx5.