vpci/msix: remove from table list on detach

Teardown of MSIX vPCI related data doesn't currently remove the MSIX
device data from the list of MSIX tables handled by the domain,
leading to a use-after-free of the data in the msix structure.

Remove the structure from the list before freeing in order to solve
it.

Reported-by: Jan Beulich <jbeulich@suse.com>
Fixes: d6281be9d0 ('vpci/msix: add MSI-X handlers')
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: c14aea137eab29eb9c30bfad745a00c65ad21066
master date: 2022-10-26 14:56:58 +0200

diff --git a/xen/drivers/vpci/vpci.c b/xen/drivers/vpci/vpci.c
index 6b90e4fa32dcb3d049470e659fc596427dc6f031..75edbbee40252750b2fcc8e1882123f7805968b3 100644 (file)
--- a/xen/drivers/vpci/vpci.c
+++ b/xen/drivers/vpci/vpci.c
@@ -51,8 +51,12 @@ void vpci_remove_device(struct pci_dev *pdev)
         xfree(r);
     }
     spin_unlock(&pdev->vpci->lock);
-    if ( pdev->vpci->msix && pdev->vpci->msix->pba )
-        iounmap(pdev->vpci->msix->pba);
+    if ( pdev->vpci->msix )
+    {
+        list_del(&pdev->vpci->msix->next);
+        if ( pdev->vpci->msix->pba )
+            iounmap(pdev->vpci->msix->pba);
+    }
     xfree(pdev->vpci->msix);
     xfree(pdev->vpci->msi);
     xfree(pdev->vpci);