vdpa: Fix error logic in vdpa_nl_cmd_dev_get_doit

[ Upstream commit 7a6691f1f89784f775fa0c54be57533445726068 ]

In vdpa_nl_cmd_dev_get_doit(), if the call to genlmsg_reply() fails we
must not call nlmsg_free() since this is done inside genlmsg_reply().

Fix it.

Fixes: bc0d90ee021f ("vdpa: Enable user to query vdpa device info")
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eli Cohen <elic@nvidia.com>
Message-Id: <20220518133804.1075129-2-elic@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index 12bf3d16a40ff2f7dcb3a1a3dd993a466fc74399..86571498c1c23cb0f6834ab52c1901f6912f8b3f 100644 (file)
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c
@@ -558,14 +558,19 @@ static int vdpa_nl_cmd_dev_get_doit(struct sk_buff *skb, struct genl_info *info)
                goto mdev_err;
        }
        err = vdpa_dev_fill(vdev, msg, info->snd_portid, info->snd_seq, 0, info->extack);
-       if (!err)
-               err = genlmsg_reply(msg, info);
+       if (err)
+               goto mdev_err;
+
+       err = genlmsg_reply(msg, info);
+       put_device(dev);
+       mutex_unlock(&vdpa_dev_mutex);
+       return err;
+
 mdev_err:
        put_device(dev);
 err:
        mutex_unlock(&vdpa_dev_mutex);
-       if (err)
-               nlmsg_free(msg);
+       nlmsg_free(msg);
        return err;
 }