vhost: correctly check the return value of translate_desc() in log_used()
[ Upstream commit 816db7663565cd23f74ed3d5c9240522e3fb0dda ]
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: cc5e71075947 ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index dc387a9..2383caf 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1696,7 +1696,7 @@
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++) {