From 3a3e0fad16d40a2aa68ddf7eea4acdf48b22dd44 Mon Sep 17 00:00:00 2001 From: Jason Wang Date: Tue, 13 Apr 2021 17:15:57 +0800 Subject: vhost-vdpa: fix vm_flags for virtqueue doorbell mapping The virtqueue doorbell is usually implemented via registeres but we don't provide the necessary vma->flags like VM_PFNMAP. This may cause several issues e.g when userspace tries to map the doorbell via vhost IOTLB, kernel may panic due to the page is not backed by page structure. This patch fixes this by setting the necessary vm_flags. With this patch, try to map doorbell via IOTLB will fail with bad address. Cc: stable@vger.kernel.org Fixes: ddd89d0a059d ("vhost_vdpa: support doorbell mapping via mmap") Signed-off-by: Jason Wang Link: https://lore.kernel.org/r/20210413091557.29008-1-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vdpa.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/vhost') diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c index bfa4c6ef554e..c79d2f2387aa 100644 --- a/drivers/vhost/vdpa.c +++ b/drivers/vhost/vdpa.c @@ -993,6 +993,7 @@ static int vhost_vdpa_mmap(struct file *file, struct vm_area_struct *vma) if (vma->vm_end - vma->vm_start != notify.size) return -ENOTSUPP; + vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP; vma->vm_ops = &vhost_vdpa_vm_ops; return 0; } -- cgit