Re: [PATCH 01/16] vfio/display: Fix error path in call site of ramfb_setup()

[Cédric Le Goater]

On 5/15/24 10:20, Zhenzhong Duan wrote:

vfio_display_dmabuf_init() and vfio_display_region_init() calls
ramfb_setup() without checking its return value.

So we may run into a situation that vfio_display_probe() succeed
but errp is set. This is risky and may lead to assert failure in
error_setv().

Cc: Gerd Hoffmann <kra...@redhat.com>
Fixes: b290659fc3d ("hw/vfio/display: add ramfb support")
Signed-off-by: Zhenzhong Duan <zhenzhong.d...@intel.com>

Reviewed-by: Cédric Le Goater <c...@redhat.com>

Thanks,

C.

---
  hw/vfio/display.c | 6 ++++++
  1 file changed, 6 insertions(+)

diff --git a/hw/vfio/display.c b/hw/vfio/display.c
index 1aa440c663..57c5ae0b2a 100644
--- a/hw/vfio/display.c
+++ b/hw/vfio/display.c
@@ -359,6 +359,9 @@ static int vfio_display_dmabuf_init(VFIOPCIDevice *vdev, 
Error **errp)
                                            vdev);
      if (vdev->enable_ramfb) {
          vdev->dpy->ramfb = ramfb_setup(errp);
+        if (!vdev->dpy->ramfb) {
+            return -EINVAL;
+        }
      }
      vfio_display_edid_init(vdev);
      return 0;
@@ -486,6 +489,9 @@ static int vfio_display_region_init(VFIOPCIDevice *vdev, 
Error **errp)
                                            vdev);
      if (vdev->enable_ramfb) {
          vdev->dpy->ramfb = ramfb_setup(errp);
+        if (!vdev->dpy->ramfb) {
+            return -EINVAL;
+        }
      }
      return 0;
  }