Commit 2ea541eb authored Apr 11, 2018 by Eric Auger Committed by Greg Kroah-Hartman Apr 19, 2018

vhost: Fix vhost_copy_to_user()




[ Upstream commit 7ced6c98c7ab7a1f6743931e28671b833af79b1e ]

vhost_copy_to_user is used to copy vring used elements to userspace.
We should use VHOST_ADDR_USED instead of VHOST_ADDR_DESC.

Fixes: f8894913 ("vhost: introduce O(1) vq metadata cache")
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent e240ffd5

drivers/vhost/vhost.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -756,7 +756,7 @@ static int vhost_copy_to_user(struct vhost_virtqueue vq, void __user to,
		struct iov_iter t;
		void __user *uaddr = vhost_vq_meta_fetch(vq,
		(u64)(uintptr_t)to, size,
		VHOST_ADDR_DESC);
		VHOST_ADDR_USED);

		if (uaddr)
		return __copy_to_user(uaddr, from, size);