The VFIO_DEVICE_SET_IRQS ioctl takes a start and count parameter, both of which are unsigned. We attempt to bounds check these, but fail to account for the case where start is a very large number, allowing start + count to wrap back into the valid range. Bounds check both start and start + count.
Reported-by: Dan Carpenter <[email protected]> Signed-off-by: Alex Williamson <[email protected]> (cherry picked from commit 904c680c7bf016a8619a045850937427f8d7368c) --- Applies correctly with fuzz back through 3.6.y. drivers/vfio/pci/vfio_pci.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index b28e66c..4a62e12 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -331,6 +331,7 @@ static long vfio_pci_ioctl(void *device_data, if (!(hdr.flags & VFIO_IRQ_SET_DATA_NONE)) { size_t size; + int max = vfio_pci_get_irq_count(vdev, hdr.index); if (hdr.flags & VFIO_IRQ_SET_DATA_BOOL) size = sizeof(uint8_t); @@ -340,7 +341,7 @@ static long vfio_pci_ioctl(void *device_data, return -EINVAL; if (hdr.argsz - minsz < hdr.count * size || - hdr.count > vfio_pci_get_irq_count(vdev, hdr.index)) + hdr.start >= max || hdr.start + hdr.count > max) return -EINVAL; data = memdup_user((void __user *)(arg + minsz), -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
