Commit b82df420 authored Apr 09, 2019 by Jason Wang Committed by Greg Kroah-Hartman Apr 27, 2019

vhost: reject zero size iova range



[ Upstream commit 813dbeb656d6c90266f251d8bd2b02d445afa63f ]

We used to accept zero size iova range which will lead a infinite loop
in translate_desc(). Fixing this by failing the request in this case.

Reported-by:  <syzbot+d21e6e297322a900c128@syzkaller.appspotmail.com>
Fixes: 6b1e6cc7 ("vhost: new device IOTLB API")
Signed-off-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 242e5746

drivers/vhost/vhost.c

+5 −1

Original line number	Diff line number	Diff line
		@@ -911,8 +911,12 @@ static int vhost_new_umem_range(struct vhost_umem *umem,
		u64 start, u64 size, u64 end,
		u64 userspace_addr, int perm)
		{
		struct vhost_umem_node tmp, node = kmalloc(sizeof(*node), GFP_ATOMIC);
		struct vhost_umem_node tmp, node;

		if (!size)
		return -EFAULT;

		node = kmalloc(sizeof(*node), GFP_ATOMIC);
		if (!node)
		return -ENOMEM;