4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jason Wang <jasowang@xxxxxxxxxx>
[ 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@xxxxxxxxxx>
Reported-by: Stephen Hemminger <stephen@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/vhost/vhost.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -1696,7 +1696,7 @@ static int log_used(struct vhost_virtque
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++) {
