On Wed, 28 Feb 2024 at 13:24, Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote: > > The dev->vqs[] array has "dev->vq_num" elements. It's allocated in > vduse_dev_init_vqs(). Thus, this > comparison needs to be >= to avoid > reading one element beyond the end of the array. > > Add an array_index_nospec() as well to prevent speculation issues. > > Fixes: 316ecd1346b0 ("vduse: Add file operation for mmap") > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > --- > v2: add array_index_nospec() > v3: I accidentally corrupted v2. Try again. > > drivers/vdpa/vdpa_user/vduse_dev.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) Reviewed-by: Stefan Hajnoczi <stefanha@xxxxxxxxxx> > diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c > index b7a1fb88c506..eb914084c650 100644 > --- a/drivers/vdpa/vdpa_user/vduse_dev.c > +++ b/drivers/vdpa/vdpa_user/vduse_dev.c > @@ -1532,9 +1532,10 @@ static int vduse_dev_mmap(struct file *file, struct vm_area_struct *vma) > if ((vma->vm_flags & VM_SHARED) == 0) > return -EINVAL; > > - if (index > dev->vq_num) > + if (index >= dev->vq_num) > return -EINVAL; > > + index = array_index_nospec(index, dev->vq_num); > vq = dev->vqs[index]; > vaddr = vq->vdpa_reconnect_vaddr; > if (vaddr == 0) > -- > 2.43.0 > >