[Qemu-devel] [PATCH] vfio-pci: Fix BAR size overflow

[Alex Williamson <alex.williamson@redhat.com>]

We use an unsigned int when working with the PCI BAR size, which can
obviously overflow if the BAR is 4GB or larger.  This needs to change
to an unsigned long.  A similar issue is possible, though even more
unlikely, when mapping the region above an MSI-X table.  The start of
the table must be below 4GB, but the end, and therefore the start of
the next mapping region, could still land at 4GB.

Suggested-by: Nishank Trivedi <nishank.trivedi@netapp.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
---

 hw/vfio/pci.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index b4e73d1..03790a8 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -2301,7 +2301,7 @@ static void vfio_unmap_bar(VFIOPCIDevice *vdev, int nr)
 static void vfio_map_bar(VFIOPCIDevice *vdev, int nr)
 {
     VFIOBAR *bar = &vdev->bars[nr];
-    unsigned size = bar->region.size;
+    unsigned long size = bar->region.size;
     char name[64];
     uint32_t pci_bar;
     uint8_t type;
@@ -2351,7 +2351,7 @@ static void vfio_map_bar(VFIOPCIDevice *vdev, int nr)
     }
 
     if (vdev->msix && vdev->msix->table_bar == nr) {
-        unsigned start;
+        unsigned long start;
 
         start = HOST_PAGE_ALIGN(vdev->msix->table_offset +
                                 (vdev->msix->entries * PCI_MSIX_ENTRY_SIZE));