| From 3ed21c1451a14d139e1ceb18f2fa70865ce3195a Mon Sep 17 00:00:00 2001 |
| From: Dan Carpenter <dan.carpenter@oracle.com> |
| Date: Wed, 8 Dec 2021 13:33:37 +0300 |
| Subject: vdpa: check that offsets are within bounds |
| |
| From: Dan Carpenter <dan.carpenter@oracle.com> |
| |
| commit 3ed21c1451a14d139e1ceb18f2fa70865ce3195a upstream. |
| |
| In this function "c->off" is a u32 and "size" is a long. On 64bit systems |
| if "c->off" is greater than "size" then "size - c->off" is a negative and |
| we always return -E2BIG. But on 32bit systems the subtraction is type |
| promoted to a high positive u32 value and basically any "c->len" is |
| accepted. |
| |
| Fixes: 4c8cf31885f6 ("vhost: introduce vDPA-based backend") |
| Reported-by: Xie Yongji <xieyongji@bytedance.com> |
| Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> |
| Link: https://lore.kernel.org/r/20211208103337.GA4047@kili |
| Signed-off-by: Michael S. Tsirkin <mst@redhat.com> |
| Cc: stable@vger.kernel.org |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/vhost/vdpa.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/drivers/vhost/vdpa.c |
| +++ b/drivers/vhost/vdpa.c |
| @@ -197,7 +197,7 @@ static int vhost_vdpa_config_validate(st |
| struct vdpa_device *vdpa = v->vdpa; |
| long size = vdpa->config->get_config_size(vdpa); |
| |
| - if (c->len == 0) |
| + if (c->len == 0 || c->off > size) |
| return -EINVAL; |
| |
| if (c->len > size - c->off) |
