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Message-ID: <dc9bfbe3-ada2-0549-e56e-975aecfd22b8@embeddedor.com>
Date:   Wed, 4 Oct 2023 01:33:46 +0200
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Subject: Re: [PATCH] net/mlx5: Annotate struct mlx5_flow_handle with
 __counted_by
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To:     Kees Cook <keescook@chromium.org>,
        Saeed Mahameed <saeedm@nvidia.com>
Cc:     Leon Romanovsky <leon@kernel.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, netdev@vger.kernel.org,
        linux-rdma@vger.kernel.org,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Tom Rix <trix@redhat.com>, linux-kernel@vger.kernel.org,
        linux-hardening@vger.kernel.org, llvm@lists.linux.dev
References: <20231003231730.work.166-kees@kernel.org>
From:   "Gustavo A. R. Silva" <gustavo@embeddedor.com>
In-Reply-To: <20231003231730.work.166-kees@kernel.org>
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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 <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_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 */