Hi Alex, Reviewed-by: Eric Auger <[email protected]> Tested-by: Eric Auger <[email protected]>
Best Regards Eric On 02/02/2016 12:54 AM, Alex Williamson wrote: > Signed versus unsigned comparisons are implicitly cast to unsigned, > which result in a couple possible overflows. For instance (start + > count) might overflow and wrap, getting through our validation test. > Also when unwinding setup, -1 being compared as unsigned doesn't > produce the intended stop condition. Fix both of these and also fix > vfio_msi_set_vector_signal() to validate parameters before using the > vector index, though none of the callers should pass bad indexes > anymore. > > Reported-by: Eric Auger <[email protected]> > Signed-off-by: Alex Williamson <[email protected]> > --- > drivers/vfio/pci/vfio_pci_intrs.c | 17 +++++++++-------- > 1 file changed, 9 insertions(+), 8 deletions(-) > > diff --git a/drivers/vfio/pci/vfio_pci_intrs.c > b/drivers/vfio/pci/vfio_pci_intrs.c > index 3b3ba15..e9ea3fe 100644 > --- a/drivers/vfio/pci/vfio_pci_intrs.c > +++ b/drivers/vfio/pci/vfio_pci_intrs.c > @@ -309,14 +309,14 @@ static int vfio_msi_set_vector_signal(struct > vfio_pci_device *vdev, > int vector, int fd, bool msix) > { > struct pci_dev *pdev = vdev->pdev; > - int irq = msix ? vdev->msix[vector].vector : pdev->irq + vector; > - char *name = msix ? "vfio-msix" : "vfio-msi"; > struct eventfd_ctx *trigger; > - int ret; > + int irq, ret; > > - if (vector >= vdev->num_ctx) > + if (vector < 0 || vector >= vdev->num_ctx) > return -EINVAL; > > + irq = msix ? vdev->msix[vector].vector : pdev->irq + vector; > + > if (vdev->ctx[vector].trigger) { > free_irq(irq, vdev->ctx[vector].trigger); > irq_bypass_unregister_producer(&vdev->ctx[vector].producer); > @@ -328,8 +328,9 @@ static int vfio_msi_set_vector_signal(struct > vfio_pci_device *vdev, > if (fd < 0) > return 0; > > - vdev->ctx[vector].name = kasprintf(GFP_KERNEL, "%s[%d](%s)", > - name, vector, pci_name(pdev)); > + vdev->ctx[vector].name = kasprintf(GFP_KERNEL, "vfio-msi%s[%d](%s)", > + msix ? "x" : "", vector, > + pci_name(pdev)); > if (!vdev->ctx[vector].name) > return -ENOMEM; > > @@ -379,7 +380,7 @@ static int vfio_msi_set_block(struct vfio_pci_device > *vdev, unsigned start, > { > int i, j, ret = 0; > > - if (start + count > vdev->num_ctx) > + if (start >= vdev->num_ctx || start + count > vdev->num_ctx) > return -EINVAL; > > for (i = 0, j = start; i < count && !ret; i++, j++) { > @@ -388,7 +389,7 @@ static int vfio_msi_set_block(struct vfio_pci_device > *vdev, unsigned start, > } > > if (ret) { > - for (--j; j >= start; j--) > + for (--j; j >= (int)start; j--) > vfio_msi_set_vector_signal(vdev, j, -1, msix); > } > >
