scsi: pm8001: fix double free in pm8001_pci_probe

In function pm8001_pci_probe(), on errors that the control flow jumps to
label err_out_ha_free, function pm8001_free() is called. In pm8001_free(),
scsi_host_put() is called to release shost, which keeps the return value
of scsi_host_alloc(). After pm8001_free() returns, kfree() is called to
free shost again, resulting in a double free bug. This patch removes
scsi_host_put() from pm8001_free() and explicitly calls scsi_host_put()
to release Scsi_Host in need.

Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/pm8001/pm8001_init.c b/drivers/scsi/pm8001/pm8001_init.c
index 034b2f7..2908881 100644 (file)
--- a/drivers/scsi/pm8001/pm8001_init.c
+++ b/drivers/scsi/pm8001/pm8001_init.c
@@ -160,8 +160,6 @@ static void pm8001_free(struct pm8001_hba_info *pm8001_ha)
                        }
        }
        PM8001_CHIP_DISP->chip_iounmap(pm8001_ha);
-       if (pm8001_ha->shost)
-               scsi_host_put(pm8001_ha->shost);
        flush_workqueue(pm8001_wq);
        kfree(pm8001_ha->tags);
        kfree(pm8001_ha);
@@ -1073,7 +1071,7 @@ err_out_ha_free:
 err_out_free:
        kfree(SHOST_TO_SAS_HA(shost));
 err_out_free_host:
-       kfree(shost);
+       scsi_host_put(shost);
 err_out_regions:
        pci_release_regions(pdev);
 err_out_disable:
@@ -1112,6 +1110,7 @@ static void pm8001_pci_remove(struct pci_dev *pdev)
                for (j = 0; j < PM8001_MAX_MSIX_VEC; j++)
                        tasklet_kill(&pm8001_ha->tasklet[j]);
 #endif
+       scsi_host_put(pm8001_ha->shost);
        pm8001_free(pm8001_ha);
        kfree(sha->sas_phy);
        kfree(sha->sas_port);