[PATCH 2/4] ipv4: consolidate the VIFF_TUNNEL handling in ipmr_new_tunnel

From: Christoph Hellwig
Date: Thu May 14 2020 - 10:51:30 EST


Also move the dev_set_allmulti call and the error handling into the
ioctl helper. This allows reusing already looked up tunnel_dev pointer
and the set up argument structure for the deletion in the error handler.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
net/ipv4/ipmr.c | 53 ++++++++++++-------------------------------------
1 file changed, 13 insertions(+), 40 deletions(-)

diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 84541c601cfab..6bf2a88abe86e 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -419,37 +419,6 @@ static void ipmr_free_table(struct mr_table *mrt)

/* Service routines creating virtual interfaces: DVMRP tunnels and PIMREG */

-static void ipmr_del_tunnel(struct net_device *dev, struct vifctl *v)
-{
- struct net *net = dev_net(dev);
-
- dev_close(dev);
-
- dev = __dev_get_by_name(net, "tunl0");
- if (dev) {
- const struct net_device_ops *ops = dev->netdev_ops;
- struct ifreq ifr;
- struct ip_tunnel_parm p;
-
- memset(&p, 0, sizeof(p));
- p.iph.daddr = v->vifc_rmt_addr.s_addr;
- p.iph.saddr = v->vifc_lcl_addr.s_addr;
- p.iph.version = 4;
- p.iph.ihl = 5;
- p.iph.protocol = IPPROTO_IPIP;
- sprintf(p.name, "dvmrp%d", v->vifc_vifi);
- ifr.ifr_ifru.ifru_data = (__force void __user *)&p;
-
- if (ops->ndo_do_ioctl) {
- mm_segment_t oldfs = get_fs();
-
- set_fs(KERNEL_DS);
- ops->ndo_do_ioctl(dev, &ifr, SIOCDELTUNNEL);
- set_fs(oldfs);
- }
- }
-}
-
/* Initialize ipmr pimreg/tunnel in_device */
static bool ipmr_init_vif_indev(const struct net_device *dev)
{
@@ -507,12 +476,22 @@ static struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
if (dev_open(new_dev, NULL))
goto out_unregister;
dev_hold(new_dev);
+ err = dev_set_allmulti(new_dev, 1);
+ if (err) {
+ dev_close(new_dev);
+ set_fs(KERNEL_DS);
+ tunnel_dev->netdev_ops->ndo_do_ioctl(tunnel_dev, &ifr,
+ SIOCDELTUNNEL);
+ set_fs(oldfs);
+ dev_put(new_dev);
+ new_dev = ERR_PTR(err);
+ }
return new_dev;

out_unregister:
unregister_netdevice(new_dev);
out:
- return NULL;
+ return ERR_PTR(-ENOBUFS);
}

#if defined(CONFIG_IP_PIMSM_V1) || defined(CONFIG_IP_PIMSM_V2)
@@ -864,14 +843,8 @@ static int vif_add(struct net *net, struct mr_table *mrt,
break;
case VIFF_TUNNEL:
dev = ipmr_new_tunnel(net, vifc);
- if (!dev)
- return -ENOBUFS;
- err = dev_set_allmulti(dev, 1);
- if (err) {
- ipmr_del_tunnel(dev, vifc);
- dev_put(dev);
- return err;
- }
+ if (IS_ERR(dev))
+ return PTR_ERR(dev);
break;
case VIFF_USE_IFINDEX:
case 0:
--
2.26.2