vhost/net: length miscalculation
commit 8b38694a2dc8b18374310df50174f1e4376d6824
vhost/net: virtio 1.0 byte swap
had this chunk:
- heads[headcount - 1].len += datalen;
+ heads[headcount - 1].len = cpu_to_vhost32(vq, len - datalen);
This adds datalen with the wrong sign, causing guest panics.
Fixes: 8b38694a2dc8b18374310df50174f1e4376d6824
Reported-by: Alex Williamson <alex.williamson@redhat.com>
Suggested-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 14419a8..d415d69 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -538,7 +538,7 @@
++headcount;
seg += in;
}
- heads[headcount - 1].len = cpu_to_vhost32(vq, len - datalen);
+ heads[headcount - 1].len = cpu_to_vhost32(vq, len + datalen);
*iovcount = seg;
if (unlikely(log))
*log_num = nlogs;
