From: Thanos Makatos <[email protected]>
This isn't in practise a problem since feature->argsz is not
externally provided, it's a good hardening step nonetheless.
Fixes: e2358af5838d ("vfio-user: support VFIO_USER_DEVICE_FEATURE")
Signed-off-by: Thanos Makatos <[email protected]>
Reviewed-by: Cédric Le Goater <[email protected]>
Link:
https://lore.kernel.org/qemu-devel/[email protected]
Signed-off-by: Cédric Le Goater <[email protected]>
---
hw/vfio-user/device.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/hw/vfio-user/device.c b/hw/vfio-user/device.c
index
3d0dbe840649b7b678b79afd3dbc7f9caaeb947b..353fa5ee21e34a88bcd0eff9de40d9757387a616
100644
--- a/hw/vfio-user/device.c
+++ b/hw/vfio-user/device.c
@@ -79,9 +79,14 @@ vfio_user_device_io_device_feature(VFIODevice *vbasedev,
struct vfio_device_feature *feature)
{
g_autofree VFIOUserDeviceFeature *msgp = NULL;
- int size = sizeof(VFIOUserHdr) + feature->argsz;
VFIOUserProxy *proxy = vbasedev->proxy;
Error *local_err = NULL;
+ int size;
+
+ if (__builtin_add_overflow(feature->argsz, sizeof(VFIOUserHdr), &size)) {
+ error_printf("vfio_user_device_io_device_feature argsz too large\n");
+ return -E2BIG;
+ }
msgp = g_malloc0(size);
--
2.55.0
