Re: [PATCH 6/6] scsi: mpt3sas: Replace a dynamic allocation with a local variable

Kees Cook
2023-07-28T22:29:22Z

On Tue, Jul 25, 2023 at 09:13:31AM -0700, James Seo wrote:
> This dynamic allocation can be replaced with a local variable.
>
> Signed-off-by: James Seo <james@equiv.tech>
> ---
> drivers/scsi/mpt3sas/mpt3sas_base.c | 19 +++++--------------
> 1 file changed, 5 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.c b/drivers/scsi/mpt3sas/mpt3sas_base.c
> index cd6f36094159..a32a6fa728a7 100644
> --- a/drivers/scsi/mpt3sas/mpt3sas_base.c
> +++ b/drivers/scsi/mpt3sas/mpt3sas_base.c
> @@ -5361,10 +5361,9 @@ _base_update_diag_trigger_pages(struct MPT3SAS_ADAPTER *ioc)
> static int _base_assign_fw_reported_qd(struct MPT3SAS_ADAPTER *ioc)
> {
> Mpi2ConfigReply_t mpi_reply;
> - Mpi2SasIOUnitPage1_t *sas_iounit_pg1 = NULL;
> + Mpi2SasIOUnitPage1_t sas_iounit_pg1;
> Mpi26PCIeIOUnitPage1_t pcie_iounit_pg1;
> u16 depth;
> - int sz;
> int rc = 0;
>
> ioc->max_wideport_qd = MPT3SAS_SAS_QUEUE_DEPTH;
> @@ -5374,28 +5373,21 @@ static int _base_assign_fw_reported_qd(struct MPT3SAS_ADAPTER *ioc)
> if (!ioc->is_gen35_ioc)
> goto out;
> /* sas iounit page 1 */
> - sz = offsetof(Mpi2SasIOUnitPage1_t, PhyData);
> - sas_iounit_pg1 = kzalloc(sizeof(Mpi2SasIOUnitPage1_t), GFP_KERNEL);

Hunh. So Mpi2SasIOUnitPage1_t is used without the flexarray at all?

-Kees

> - if (!sas_iounit_pg1) {
> - pr_err("%s: failure at %s:%d/%s()!\n",
> - ioc->name, __FILE__, __LINE__, __func__);
> - return rc;
> - }
> rc = mpt3sas_config_get_sas_iounit_pg1(ioc, &mpi_reply,
> - sas_iounit_pg1, sz);
> + &sas_iounit_pg1, sizeof(Mpi2SasIOUnitPage1_t));
> if (rc) {
> pr_err("%s: failure at %s:%d/%s()!\n",
> ioc->name, __FILE__, __LINE__, __func__);
> goto out;
> }
>
> - depth = le16_to_cpu(sas_iounit_pg1->SASWideMaxQueueDepth);
> + depth = le16_to_cpu(sas_iounit_pg1.SASWideMaxQueueDepth);
> ioc->max_wideport_qd = (depth ? depth : MPT3SAS_SAS_QUEUE_DEPTH);
>
> - depth = le16_to_cpu(sas_iounit_pg1->SASNarrowMaxQueueDepth);
> + depth = le16_to_cpu(sas_iounit_pg1.SASNarrowMaxQueueDepth);
> ioc->max_narrowport_qd = (depth ? depth : MPT3SAS_SAS_QUEUE_DEPTH);
>
> - depth = sas_iounit_pg1->SATAMaxQDepth;
> + depth = sas_iounit_pg1.SATAMaxQDepth;
> ioc->max_sata_qd = (depth ? depth : MPT3SAS_SATA_QUEUE_DEPTH);
>
> /* pcie iounit page 1 */
> @@ -5414,7 +5406,6 @@ static int _base_assign_fw_reported_qd(struct MPT3SAS_ADAPTER *ioc)
> "MaxWidePortQD: 0x%x MaxNarrowPortQD: 0x%x MaxSataQD: 0x%x MaxNvmeQD: 0x%x\n",
> ioc->max_wideport_qd, ioc->max_narrowport_qd,
> ioc->max_sata_qd, ioc->max_nvme_qd));
> - kfree(sas_iounit_pg1);
> return rc;
> }
>
> --
> 2.39.2
>

--
Kees Cook