2023-10-03 23:18:00

by Kees Cook

Subject: [PATCH] net/mlx5: Annotate struct mlx5_fc_bulk 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_fc_bulk.

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_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

2023-10-03 23:21:45

by Justin Stitt

Subject: Re: [PATCH] net/mlx5: Annotate struct mlx5_fc_bulk 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_fc_bulk.
>
> 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_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 <[email protected]>
>
> static void mlx5_fc_init(struct mlx5_fc *counter, struct mlx5_fc_bulk *bulk,
> --
> 2.34.1
>
>
Thanks
Justin

2023-10-03 23:33:52

by Gustavo A. R. Silva

Subject: Re: [PATCH] net/mlx5: Annotate struct mlx5_fc_bulk 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_fc_bulk.
>
> 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_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,

2023-10-04 18:46:14

by Leon Romanovsky

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

On Tue, Oct 03, 2023 at 04:21:05PM -0700, Justin Stitt wrote:
> 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_fc_bulk.
> >
> > 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_counters.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >

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

2023-10-12 19:49:13

by Saeed Mahameed

Subject: Re: [PATCH] net/mlx5: Annotate struct mlx5_fc_bulk 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_fc_bulk.
>
>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.