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

From: Gustavo A. R. Silva
Date: Thu Jul 11 2024 - 12:17:52 EST




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)