tun: handle ubuf refcount correctly when meet errors
authorJason Wang <jasowang@redhat.com>
Wed, 30 Nov 2016 05:17:51 +0000 (13:17 +0800)
committerDavid S. Miller <davem@davemloft.net>
Wed, 30 Nov 2016 20:06:01 +0000 (15:06 -0500)
commitaf1cc7a2b86ddb8668ac38097866bedd7b849a76
tree2bf4382bcca7c8ce0e04e5395436c620cbcd0de2
parent4ccfd6383a1a4838ed034120f00d02dbdc681d6f
tun: handle ubuf refcount correctly when meet errors

We trigger uarg->callback() immediately after we decide do datacopy
even if caller want to do zerocopy. This will cause the callback
(vhost_net_zerocopy_callback) decrease the refcount. But when we meet
an error afterwards, the error handling in vhost handle_tx() will try
to decrease it again. This is wrong and fix this by delay the
uarg->callback() until we're sure there's no errors.

Reported-by: wangyunjian <wangyunjian@huawei.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/tun.c