Re: [PATCH 2/4] scsi: mpi3mr: struct mpi3_event_data_pcie_topology_change_list: Replace 1-element array with flexible array

[Gustavo A. R. Silva]

On 11/07/24 09:56, Kees Cook wrote:
> Replace the deprecated[1] use of a 1-element array in
> struct mpi3_event_data_pcie_topology_change_list with a modern
> flexible array.
>
> Additionally add __counted_by annotation since port_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->port_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@xxxxxxxxxx>

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

Thanks
--
Gustavo

> ---
> Cc: Sathya Prakash Veerichetty <sathya.prakash@xxxxxxxxxxxx>
> Cc: Kashyap Desai <kashyap.desai@xxxxxxxxxxxx>
> Cc: Sumit Saxena <sumit.saxena@xxxxxxxxxxxx>
> Cc: Sreekanth Reddy <sreekanth.reddy@xxxxxxxxxxxx>
> Cc: "James E.J. Bottomley" <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
> Cc: "Martin K. Petersen" <martin.petersen@xxxxxxxxxx>
> Cc: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx>
> Cc: Ranjan Kumar <ranjan.kumar@xxxxxxxxxxxx>
> Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
> Cc: mpi3mr-linuxdrv.pdl@xxxxxxxxxxxx
> Cc: linux-scsi@xxxxxxxxxxxxxxx
> Cc: linux-hardening@xxxxxxxxxxxxxxx
> ---
>   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 ae74fccc65b8..c9fa0d69b75f 100644
> --- a/drivers/scsi/mpi3mr/mpi/mpi30_ioc.h
> +++ b/drivers/scsi/mpi3mr/mpi/mpi30_ioc.h
> @@ -542,9 +542,6 @@ struct mpi3_event_data_pcie_enumeration {
>   #define MPI3_EVENT_PCIE_ENUM_ES_MAX_SWITCHES_EXCEED         (0x40000000)
>   #define MPI3_EVENT_PCIE_ENUM_ES_MAX_DEVICES_EXCEED          (0x20000000)
>   #define MPI3_EVENT_PCIE_ENUM_ES_RESOURCES_EXHAUSTED         (0x10000000)
> -#ifndef MPI3_EVENT_PCIE_TOPO_PORT_COUNT
> -#define MPI3_EVENT_PCIE_TOPO_PORT_COUNT         (1)
> -#endif
>   struct mpi3_event_pcie_topo_port_entry {
>   	__le16             attached_dev_handle;
>   	u8                 port_status;
> @@ -585,7 +582,7 @@ struct mpi3_event_data_pcie_topology_change_list {
>   	u8                                     switch_status;
>   	u8                                     io_unit_port;
>   	__le32                                 reserved0c;
> -	struct mpi3_event_pcie_topo_port_entry     port_entry[MPI3_EVENT_PCIE_TOPO_PORT_COUNT];
> +	struct mpi3_event_pcie_topo_port_entry     port_entry[] __counted_by(num_entries);
>   };
>   
>   #define MPI3_EVENT_PCIE_TOPO_SS_NO_PCIE_SWITCH          (0x00)