re: scsi: hisi_sas: Fix some issues related to, asd_sas_port->phy_list

[Colin King (gmail)]

Hi,

Static analysis with clang-scan has found a dereference of an 
uninitialized pointer in drivers/scsi/hisi_sas/hisi_sas_main.c 
introduced by the following recent commit:

commit 29e2bac87421c613782ccb510c76c5efbecac0cf
Author: Xiang Chen <chenxiang66@xxxxxxxxxxxxx>
Date:   Mon Dec 20 19:21:28 2021 +0800

    scsi: hisi_sas: Fix some issues related to asd_sas_port->phy_list

The issue is as follows:

static void hisi_sas_send_ata_reset_each_phy(struct hisi_hba *hisi_hba,
                                             struct asd_sas_port *sas_port,
                                             struct domain_device *device)
{
        struct hisi_sas_tmf_task tmf_task = { .force_phy = 1 };
        struct ata_port *ap = device->sata_dev.ap;
        struct device *dev = hisi_hba->dev;
        int s = sizeof(struct host_to_dev_fis);
        int rc = TMF_RESP_FUNC_FAILED;
        struct asd_sas_phy *sas_phy;

sas_phy is not initialized ^

        struct ata_link *link;
        u8 fis[20] = {0};
        u32 state;
        int i;

        state = hisi_hba->hw->get_phys_state(hisi_hba);
        for (i = 0; i < hisi_hba->n_phy; i++) {
                if (!(state & BIT(sas_phy->id)))
                        continue;

sas_phy is being dereferenced

The commit referenced above removed the statement:

   list_for_each_entry(sas_phy, &sas_port->phy_list, port_phy_el)


..that set sas_phy. Now we don't have this, so sas_phy is not initialized.

Colin