Re: [PATCH 5/6] scsi: message: fusion: struct _CONFIG_PAGE_IOC_3: Replace 1-element array with flexible array

[Gustavo A. R. Silva]

On 11/07/24 11:28, Kees Cook wrote:
> Replace the deprecated[1] use of a 1-element array in
> struct _CONFIG_PAGE_IOC_3 with a modern flexible array.
>
> Additionally add __counted_by annotation since PhysDisk is only ever
> accessed via a loops bounded by NumPhysDisks:
>
> lsi/mpi_cnfg.h:    IOC_3_PHYS_DISK             PhysDisk[] __counted_by(NumPhysDisks); /* 08h */
> mptscsih.c:	for (i = 0; i < ioc->raid_data.pIocPg3->NumPhysDisks; i++) {
> mptscsih.c:		if ((id == ioc->raid_data.pIocPg3->PhysDisk[i].PhysDiskID) &&
> mptscsih.c:		    (channel == ioc->raid_data.pIocPg3->PhysDisk[i].PhysDiskBus)) {
> mptscsih.c:	for (i = 0; i < ioc->raid_data.pIocPg3->NumPhysDisks; i++) {
> mptscsih.c:		    ioc->raid_data.pIocPg3->PhysDisk[i].PhysDiskNum);
> mptscsih.c:		    ioc->raid_data.pIocPg3->PhysDisk[i].PhysDiskNum,
> mptscsih.c:	for (i = 0; i < ioc->raid_data.pIocPg3->NumPhysDisks; i++) {
> mptscsih.c:		if ((id == ioc->raid_data.pIocPg3->PhysDisk[i].PhysDiskID) &&
> mptscsih.c:		    (channel == ioc->raid_data.pIocPg3->PhysDisk[i].PhysDiskBus)) {
> mptscsih.c:			rc = ioc->raid_data.pIocPg3->PhysDisk[i].PhysDiskNum;
> mptscsih.c:	for (i = 0; i < ioc->raid_data.pIocPg3->NumPhysDisks; i++) {
> mptscsih.c:		    ioc->raid_data.pIocPg3->PhysDisk[i].PhysDiskNum);
> mptscsih.c:		    ioc->raid_data.pIocPg3->PhysDisk[i].PhysDiskNum,
>
> 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 <sathya.prakash@xxxxxxxxxxxx>
> Cc: Sreekanth Reddy <sreekanth.reddy@xxxxxxxxxxxx>
> Cc: Suganath Prabu Subramani <suganath-prabu.subramani@xxxxxxxxxxxx>
> Cc: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx>
> Cc: MPT-FusionLinux.pdl@xxxxxxxxxxxx
> Cc: linux-scsi@xxxxxxxxxxxxxxx
> Cc: linux-hardening@xxxxxxxxxxxxxxx
> ---
>   drivers/message/fusion/lsi/mpi_cnfg.h | 10 +---------
>   1 file changed, 1 insertion(+), 9 deletions(-)
>
> diff --git a/drivers/message/fusion/lsi/mpi_cnfg.h b/drivers/message/fusion/lsi/mpi_cnfg.h
> index 7713c74e515b..bac49c162165 100644
> --- a/drivers/message/fusion/lsi/mpi_cnfg.h
> +++ b/drivers/message/fusion/lsi/mpi_cnfg.h
> @@ -1056,21 +1056,13 @@ typedef struct _IOC_3_PHYS_DISK
>   } IOC_3_PHYS_DISK, MPI_POINTER PTR_IOC_3_PHYS_DISK,
>     Ioc3PhysDisk_t, MPI_POINTER pIoc3PhysDisk_t;
>   
> -/*
> - * Host code (drivers, BIOS, utilities, etc.) should leave this define set to
> - * one and check Header.PageLength at runtime.
> - */
> -#ifndef MPI_IOC_PAGE_3_PHYSDISK_MAX
> -#define MPI_IOC_PAGE_3_PHYSDISK_MAX         (1)
> -#endif
> -
>   typedef struct _CONFIG_PAGE_IOC_3
>   {
>       CONFIG_PAGE_HEADER          Header;                                /* 00h */
>       U8                          NumPhysDisks;                          /* 04h */
>       U8                          Reserved1;                             /* 05h */
>       U16                         Reserved2;                             /* 06h */
> -    IOC_3_PHYS_DISK             PhysDisk[MPI_IOC_PAGE_3_PHYSDISK_MAX]; /* 08h */
> +    IOC_3_PHYS_DISK             PhysDisk[] __counted_by(NumPhysDisks); /* 08h */
>   } CONFIG_PAGE_IOC_3, MPI_POINTER PTR_CONFIG_PAGE_IOC_3,
>     IOCPage3_t, MPI_POINTER pIOCPage3_t;
>