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 <k...@kernel.org>

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

Thanks
--
Gustavo

---
Cc: Sathya Prakash <sathya.prak...@broadcom.com>
Cc: Sreekanth Reddy <sreekanth.re...@broadcom.com>
Cc: Suganath Prabu Subramani <suganath-prabu.subram...@broadcom.com>
Cc: "Gustavo A. R. Silva" <gustavo...@kernel.org>
Cc: mpt-fusionlinux....@broadcom.com
Cc: linux-s...@vger.kernel.org
Cc: linux-hardening@vger.kernel.org
---
  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;