On 4/13/2017 5:02 PM, Bjorn Helgaas wrote:
> I do see that you change the deallocation in patch [5/5], but I think
> the deallocation change should be in the same patch as the allocation
> change. Otherwise I think we have a use-after-free problem in this
> sequence:
Sure, I'll reorder. As you can see here, link will be only removed if
root port is being removed.
Without this, we'll hit the use after free issue you mentioned.
if (pdev->has_secondary_link) {
link = pdev->link_state;
down_read(&pci_bus_sem);
mutex_lock(&aspm_lock);
list_del(&link->sibling);
list_del(&link->link);
/* Clock PM is for endpoint device */
free_link_state(link);
mutex_unlock(&aspm_lock);
up_read(&pci_bus_sem);
return;
}
--
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux
Foundation Collaborative Project.
