Re: [PATCH] pci/hotplug: fix potential memory leak in disable_slot()

[Niklas Schnelle]

On 21/03/2021 16:51, Zhiqiang Liu wrote:

In disable_slot(), if we obtain desired PCI device
successfully by calling pci_get_slot(), we should
call pci_dev_put() to release its reference.

Thanks for the patch! This should however be fixed independently by 
commit 0b13525c20fe ("s390/pci: fix leak of PCI device structure")
which was just added to v5.12-rc4 and will be backported to stable.
There were a few similar cases that also got fixed by that commit.


Signed-off-by: Zhiqiang Liu <liuzhiqian...@huawei.com>
Signed-off-by: Feilong Lin <linfeil...@huawei.com>
---
  drivers/pci/hotplug/s390_pci_hpc.c | 6 ++++--
  1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/hotplug/s390_pci_hpc.c 
b/drivers/pci/hotplug/s390_pci_hpc.c
index c9e790c74051..999a34b6fd50 100644
--- a/drivers/pci/hotplug/s390_pci_hpc.c
+++ b/drivers/pci/hotplug/s390_pci_hpc.c
@@ -89,9 +89,11 @@ static int disable_slot(struct hotplug_slot *hotplug_slot)
                return -EIO;

        pdev = pci_get_slot(zdev->zbus->bus, zdev->devfn);
-       if (pdev && pci_num_vf(pdev)) {
+       if (pdev) {
+               rc = pci_num_vf(pdev);
                pci_dev_put(pdev);
-               return -EBUSY;
+               if (rc)
+                       return -EBUSY;
        }

        zpci_remove_device(zdev);