lkml.org 
[lkml]   [2020]   [May]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3/4] ipv4: use symbol_get to access ipip symbols
Date
Instead of going through the ioctl handler from kernel space, use
symbol_get to access the ip_tunnel_ioctl directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
net/ipv4/ipmr.c | 28 ++++++++++++----------------
1 file changed, 12 insertions(+), 16 deletions(-)

diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 6bf2a88abe86e..3780ab694c574 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -438,10 +438,9 @@ static bool ipmr_init_vif_indev(const struct net_device *dev)

static struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
{
- mm_segment_t oldfs = get_fs();
+ int (*tunnel_ctl)(struct net_device *, struct ip_tunnel_parm *, int);
struct net_device *tunnel_dev, *new_dev;
struct ip_tunnel_parm p = { };
- struct ifreq ifr;
int err;

tunnel_dev = __dev_get_by_name(net, "tunl0");
@@ -454,21 +453,17 @@ static struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
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 (!tunnel_dev->netdev_ops->ndo_do_ioctl)
- goto out;
+ tunnel_ctl = symbol_get(ip_tunnel_ioctl);
+ if (!tunnel_ctl)
+ return ERR_PTR(-ENOBUFS);

- set_fs(KERNEL_DS);
- err = tunnel_dev->netdev_ops->ndo_do_ioctl(tunnel_dev, &ifr,
- SIOCADDTUNNEL);
- set_fs(oldfs);
- if (err)
- goto out;
+ if (tunnel_ctl(tunnel_dev, &p, SIOCADDTUNNEL))
+ goto out_symbol_put;

new_dev = __dev_get_by_name(net, p.name);
if (!new_dev)
- goto out;
+ goto out_symbol_put;

new_dev->flags |= IFF_MULTICAST;
if (!ipmr_init_vif_indev(new_dev))
@@ -479,17 +474,18 @@ static struct net_device *ipmr_new_tunnel(struct net *net, struct vifctl *v)
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);
+ tunnel_ctl(tunnel_dev, &p, SIOCDELTUNNEL);
dev_put(new_dev);
new_dev = ERR_PTR(err);
}
+
+ symbol_put(ip_tunnel_ioctl);
return new_dev;

out_unregister:
unregister_netdevice(new_dev);
+out_symbol_put:
+ symbol_put(ipmr_new_tunnel);
out:
return ERR_PTR(-ENOBUFS);
}
--
2.26.2
\
 
 \ /
  Last update: 2020-05-14 16:52    [W:0.111 / U:0.092 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site