vhost: fix length for cross region descriptor

If a single descriptor crosses a region, the
second chunk length should be decremented
by size translated so far, instead it includes
the full descriptor length.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Michael S. Tsirkin 2012-11-26 05:57:27 +00:00 committed by David S. Miller
parent c3b2c25819
commit bd97120fc3

View File

@ -1076,7 +1076,7 @@ static int translate_desc(struct vhost_dev *dev, u64 addr, u32 len,
}
_iov = iov + ret;
size = reg->memory_size - addr + reg->guest_phys_addr;
_iov->iov_len = min((u64)len, size);
_iov->iov_len = min((u64)len - s, size);
_iov->iov_base = (void __user *)(unsigned long)
(reg->userspace_addr + addr - reg->guest_phys_addr);
s += size;