vhost: correctly check the return value of translate_desc() in log_used()

When fail, translate_desc() returns negative value, otherwise the
number of iovs. So we should fail when the return value is negative
instead of a blindly check against zero.

Detected by CoverityScan, CID# 1442593:  Control flow issues  (DEADCODE)

Fixes: cc5e710759 ("vhost: log dirty page correctly")
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reported-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jason Wang 2019-02-19 14:53:44 +08:00 committed by David S. Miller
parent 5cd856a5ef
commit 816db76635

View File

@ -1788,7 +1788,7 @@ static int log_used(struct vhost_virtqueue *vq, u64 used_offset, u64 len)
ret = translate_desc(vq, (uintptr_t)vq->used + used_offset,
len, iov, 64, VHOST_ACCESS_WO);
if (ret)
if (ret < 0)
return ret;
for (i = 0; i < ret; i++) {