| Message ID | 20200610085852.GB5439@mwanda (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | vhost_vdpa: Fix potential underflow in vhost_vdpa_mmap() | expand |
On Wed, Jun 10, 2020 at 11:58:52AM +0300, Dan Carpenter wrote: > The "vma->vm_pgoff" variable is an unsigned long so if it's larger than > INT_MAX then "index" can be negative leading to an underflow. Fix this > by changing the type of "index" to "unsigned long". > > Fixes: ddd89d0a059d ("vhost_vdpa: support doorbell mapping via mmap") > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Applied, thanks! > --- > drivers/vhost/vdpa.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c > index 7580e34f76c10..a54b60d6623f0 100644 > --- a/drivers/vhost/vdpa.c > +++ b/drivers/vhost/vdpa.c > @@ -818,7 +818,7 @@ static int vhost_vdpa_mmap(struct file *file, struct vm_area_struct *vma) > struct vdpa_device *vdpa = v->vdpa; > const struct vdpa_config_ops *ops = vdpa->config; > struct vdpa_notification_area notify; > - int index = vma->vm_pgoff; > + unsigned long index = vma->vm_pgoff; > > if (vma->vm_end - vma->vm_start != PAGE_SIZE) > return -EINVAL; > -- > 2.26.2
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c index 7580e34f76c10..a54b60d6623f0 100644 --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -818,7 +818,7 @@ static int vhost_vdpa_mmap(struct file *file, struct vm_area_struct *vma) struct vdpa_device *vdpa = v->vdpa; const struct vdpa_config_ops *ops = vdpa->config; struct vdpa_notification_area notify; - int index = vma->vm_pgoff; + unsigned long index = vma->vm_pgoff; if (vma->vm_end - vma->vm_start != PAGE_SIZE) return -EINVAL;
The "vma->vm_pgoff" variable is an unsigned long so if it's larger than INT_MAX then "index" can be negative leading to an underflow. Fix this by changing the type of "index" to "unsigned long". Fixes: ddd89d0a059d ("vhost_vdpa: support doorbell mapping via mmap") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> --- drivers/vhost/vdpa.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)