Re: [PATCH 1/4] scsi: mpi3mr: struct mpi3_event_data_sas_topology_change_list: Replace 1-element array with flexible array

["Gustavo A. R. Silva" <gustavo@embeddedor.com>]

On 11/07/24 09:56, Kees Cook wrote:
> Replace the deprecated[1] use of a 1-element array in
> struct mpi3_event_data_sas_topology_change_list with a modern
> flexible array.
> 
> Additionally add __counted_by annotation since phy_entry is only ever
> accessed in loops controlled by num_entries. For example:
> 
>          for (i = 0; i < event_data->num_entries; i++) {
> 		...
>                  handle = le16_to_cpu(event_data->phy_entry[i].attached_dev_handle);
> 
> No binary differences are present after this conversion.
> 
> Link: https://github.com/KSPP/linux/issues/79 [1]
> Signed-off-by: Kees Cook <kees@kernel.org>

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

Thanks
-- 
Gustavo

> ---
> Cc: Sathya Prakash Veerichetty <sathya.prakash@broadcom.com>
> Cc: Kashyap Desai <kashyap.desai@broadcom.com>
> Cc: Sumit Saxena <sumit.saxena@broadcom.com>
> Cc: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
> Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
> Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
> Cc: Ranjan Kumar <ranjan.kumar@broadcom.com>
> Cc: Stephen Rothwell <sfr@canb.auug.org.au>
> Cc: mpi3mr-linuxdrv.pdl@broadcom.com
> Cc: linux-scsi@vger.kernel.org
> Cc: linux-hardening@vger.kernel.org
> ---
>   drivers/scsi/mpi3mr/mpi/mpi30_ioc.h | 5 +----
>   1 file changed, 1 insertion(+), 4 deletions(-)
> 
> diff --git a/drivers/scsi/mpi3mr/mpi/mpi30_ioc.h b/drivers/scsi/mpi3mr/mpi/mpi30_ioc.h
> index 028784949873..ae74fccc65b8 100644
> --- a/drivers/scsi/mpi3mr/mpi/mpi30_ioc.h
> +++ b/drivers/scsi/mpi3mr/mpi/mpi30_ioc.h
> @@ -453,9 +453,6 @@ struct mpi3_event_data_sas_notify_primitive {
>   #define MPI3_EVENT_NOTIFY_PRIMITIVE_POWER_LOSS_EXPECTED   (0x02)
>   #define MPI3_EVENT_NOTIFY_PRIMITIVE_RESERVED1             (0x03)
>   #define MPI3_EVENT_NOTIFY_PRIMITIVE_RESERVED2             (0x04)
> -#ifndef MPI3_EVENT_SAS_TOPO_PHY_COUNT
> -#define MPI3_EVENT_SAS_TOPO_PHY_COUNT           (1)
> -#endif
>   struct mpi3_event_sas_topo_phy_entry {
>   	__le16             attached_dev_handle;
>   	u8                 link_rate;
> @@ -496,7 +493,7 @@ struct mpi3_event_data_sas_topology_change_list {
>   	u8                                 start_phy_num;
>   	u8                                 exp_status;
>   	u8                                 io_unit_port;
> -	struct mpi3_event_sas_topo_phy_entry   phy_entry[MPI3_EVENT_SAS_TOPO_PHY_COUNT];
> +	struct mpi3_event_sas_topo_phy_entry   phy_entry[] __counted_by(num_entries);
>   };
>   
>   #define MPI3_EVENT_SAS_TOPO_ES_NO_EXPANDER              (0x00)