Re: [PATCH] nvmet-fc: Annotate struct nvmet_fc_tgt_queue with __counted_by

[Gustavo A. R. Silva]

On 10/4/23 01:25, 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 nvmet_fc_tgt_queue.
>
> Cc: James Smart <james.smart@xxxxxxxxxxxx>
> Cc: Christoph Hellwig <hch@xxxxxx>
> Cc: Sagi Grimberg <sagi@xxxxxxxxxxx>
> Cc: Chaitanya Kulkarni <kch@xxxxxxxxxx>
> Cc: linux-nvme@xxxxxxxxxxxxxxxxxxx
> Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

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

Thanks
--
Gustavo

> ---
>   drivers/nvme/target/fc.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/nvme/target/fc.c b/drivers/nvme/target/fc.c
> index 1ab6601fdd5c..0fa2d658cdeb 100644
> --- a/drivers/nvme/target/fc.c
> +++ b/drivers/nvme/target/fc.c
> @@ -146,7 +146,7 @@ struct nvmet_fc_tgt_queue {
>   	struct workqueue_struct		*work_q;
>   	struct kref			ref;
>   	struct rcu_head			rcu;
> -	struct nvmet_fc_fcp_iod		fod[];		/* array of fcp_iods */
> +	struct nvmet_fc_fcp_iod		fod[] __counted_by(sqsize); /* array of fcp_iods */
>   } __aligned(sizeof(unsigned long long));
>   
>   struct nvmet_fc_hostport {