[PATCH] net/mlx5: Annotate struct mlx5_fc_bulk with __counted_by

[PATCH] net/mlx5: Annotate struct mlx5_fc_bulk with __counted_by

[Kees Cook]

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_fc_bulk.

Cc: Saeed Mahameed <saeedm@nvidia.com>
Cc: Leon Romanovsky <leon@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: netdev@vger.kernel.org
Cc: linux-rdma@vger.kernel.org
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
Signed-off-by: Kees Cook <keescook@chromium.org>
---
 drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c b/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c
index 17fe30a4c06c..0c26d707eed2 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c
@@ -539,7 +539,7 @@ struct mlx5_fc_bulk {
 	u32 base_id;
 	int bulk_len;
 	unsigned long *bitmask;
-	struct mlx5_fc fcs[];
+	struct mlx5_fc fcs[] __counted_by(bulk_len);
 };
 
 static void mlx5_fc_init(struct mlx5_fc *counter, struct mlx5_fc_bulk *bulk,
-- 
2.34.1

Re: [PATCH] net/mlx5: Annotate struct mlx5_fc_bulk with __counted_by

[Justin Stitt]

On Tue, Oct 3, 2023 at 4:17 PM Kees Cook <keescook@chromium.org> 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_fc_bulk.
>
> Cc: Saeed Mahameed <saeedm@nvidia.com>
> Cc: Leon Romanovsky <leon@kernel.org>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Eric Dumazet <edumazet@google.com>
> Cc: Jakub Kicinski <kuba@kernel.org>
> Cc: Paolo Abeni <pabeni@redhat.com>
> Cc: netdev@vger.kernel.org
> Cc: linux-rdma@vger.kernel.org
> Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> Signed-off-by: Kees Cook <keescook@chromium.org>
> ---
>  drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c b/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c
> index 17fe30a4c06c..0c26d707eed2 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c
> @@ -539,7 +539,7 @@ struct mlx5_fc_bulk {
>         u32 base_id;
>         int bulk_len;
>         unsigned long *bitmask;
> -       struct mlx5_fc fcs[];
> +       struct mlx5_fc fcs[] __counted_by(bulk_len);
>  };

This looks good.

`bulk->bulk_len` is assigned before flexible array member `fcs` is accessed.

        bulk->bulk_len = bulk_len;
        for (i = 0; i < bulk_len; i++) {
                mlx5_fc_init(&bulk->fcs[i], bulk, base_id + i);
                set_bit(i, bulk->bitmask);
        }

Reviewed-by: Justin Stitt <justinstitt@google.com>
>
>  static void mlx5_fc_init(struct mlx5_fc *counter, struct mlx5_fc_bulk *bulk,
> --
> 2.34.1
>
>
Thanks
Justin

Re: [PATCH] net/mlx5: Annotate struct mlx5_fc_bulk with __counted_by

[Leon Romanovsky]

On Tue, Oct 03, 2023 at 04:21:05PM -0700, Justin Stitt wrote:
> On Tue, Oct 3, 2023 at 4:17 PM Kees Cook <keescook@chromium.org> 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_fc_bulk.
> >
> > Cc: Saeed Mahameed <saeedm@nvidia.com>
> > Cc: Leon Romanovsky <leon@kernel.org>
> > Cc: "David S. Miller" <davem@davemloft.net>
> > Cc: Eric Dumazet <edumazet@google.com>
> > Cc: Jakub Kicinski <kuba@kernel.org>
> > Cc: Paolo Abeni <pabeni@redhat.com>
> > Cc: netdev@vger.kernel.org
> > Cc: linux-rdma@vger.kernel.org
> > Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> > Signed-off-by: Kees Cook <keescook@chromium.org>
> > ---
> >  drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >

Thanks,
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>

Re: [PATCH] net/mlx5: Annotate struct mlx5_fc_bulk with __counted_by

[Gustavo A. R. Silva]

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_fc_bulk.
> 
> Cc: Saeed Mahameed <saeedm@nvidia.com>
> Cc: Leon Romanovsky <leon@kernel.org>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Eric Dumazet <edumazet@google.com>
> Cc: Jakub Kicinski <kuba@kernel.org>
> Cc: Paolo Abeni <pabeni@redhat.com>
> Cc: netdev@vger.kernel.org
> Cc: linux-rdma@vger.kernel.org
> Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> Signed-off-by: Kees Cook <keescook@chromium.org>

Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Thanks
--
Gustavo

> ---
>   drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c b/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c
> index 17fe30a4c06c..0c26d707eed2 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_counters.c
> @@ -539,7 +539,7 @@ struct mlx5_fc_bulk {
>   	u32 base_id;
>   	int bulk_len;
>   	unsigned long *bitmask;
> -	struct mlx5_fc fcs[];
> +	struct mlx5_fc fcs[] __counted_by(bulk_len);
>   };
>   
>   static void mlx5_fc_init(struct mlx5_fc *counter, struct mlx5_fc_bulk *bulk,

Re: [PATCH] net/mlx5: Annotate struct mlx5_fc_bulk with __counted_by

[Saeed Mahameed]

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_fc_bulk.
>
>Cc: Saeed Mahameed <saeedm@nvidia.com>
>Cc: Leon Romanovsky <leon@kernel.org>
>Cc: "David S. Miller" <davem@davemloft.net>
>Cc: Eric Dumazet <edumazet@google.com>
>Cc: Jakub Kicinski <kuba@kernel.org>
>Cc: Paolo Abeni <pabeni@redhat.com>
>Cc: netdev@vger.kernel.org
>Cc: linux-rdma@vger.kernel.org
>Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
>Signed-off-by: Kees Cook <keescook@chromium.org>

Applied to net-next-mlx5.