[PATCH 3/9] net: add a new ndo_tunnel_ioctl method

From: Christoph Hellwig
Date: Mon May 18 2020 - 07:47:21 EST

Next message: Christoph Hellwig: "[PATCH 7/9] ipv6: stub out even more of addrconf_set_dstaddr if SIT is disabled"
Previous message: Christoph Hellwig: "[PATCH 2/9] ipv4: consolidate the VIFF_TUNNEL handling in ipmr_new_tunnel"
In reply to: Christoph Hellwig: "[PATCH 2/9] ipv4: consolidate the VIFF_TUNNEL handling in ipmr_new_tunnel"
Next in thread: Christoph Hellwig: "[PATCH 7/9] ipv6: stub out even more of addrconf_set_dstaddr if SIT is disabled"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

This method is used to properly allow kernel callers of the IPv4 route
management ioctls. The exsting ip_tunnel_ioctl helper is renamed to
ip_tunnel_ctl to better reflect that it doesn't directly implement ioctls
touching user memory, and is used for the guts of ndo_tunnel_ctl
implementations. A new ip_tunnel_ioctl helper is added that can be wired
up directly to the ndo_do_ioctl method and takes care of the copy to and
from userspace.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
include/linux/netdevice.h | 6 ++++++
include/net/ip_tunnels.h | 3 ++-
net/ipv4/ip_gre.c | 35 ++++++++++++++---------------------
net/ipv4/ip_tunnel.c | 16 +++++++++++++++-
net/ipv4/ip_vti.c | 32 +++++++++++++-------------------
net/ipv4/ipip.c | 30 +++++++++---------------------
6 files changed, 59 insertions(+), 63 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 6a8f8daef09df..a18f8fdf4260a 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -53,6 +53,7 @@ struct netpoll_info;
struct device;
struct phy_device;
struct dsa_port;
+struct ip_tunnel_parm;
struct macsec_context;
struct macsec_ops;

@@ -1274,6 +1275,9 @@ struct netdev_net_notifier {
* Get devlink port instance associated with a given netdev.
* Called with a reference on the netdevice and devlink locks only,
* rtnl_lock is not held.
+ * int (*ndo_tunnel_ctl)(struct net_device *dev, struct ip_tunnel_parm *p,
+ * int cmd);
+ * Add, change, delete or get information on an IPv4 tunnel.
*/
struct net_device_ops {
int (*ndo_init)(struct net_device *dev);
@@ -1479,6 +1483,8 @@ struct net_device_ops {
int (*ndo_xsk_wakeup)(struct net_device *dev,
u32 queue_id, u32 flags);
struct devlink_port * (*ndo_get_devlink_port)(struct net_device *dev);
+ int (*ndo_tunnel_ctl)(struct net_device *dev,
+ struct ip_tunnel_parm *p, int cmd);
};

/**
diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h
index 236503a50759a..076e5d7db7d3c 100644
--- a/include/net/ip_tunnels.h
+++ b/include/net/ip_tunnels.h
@@ -269,7 +269,8 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
const struct iphdr *tnl_params, const u8 protocol);
void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
const u8 proto, int tunnel_hlen);
-int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd);
+int ip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd);
+int ip_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);
int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict);
int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu);

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 0ce9b91ff55c0..4e31f23e4117e 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -768,45 +768,37 @@ static void ipgre_link_update(struct net_device *dev, bool set_mtu)
}
}

-static int ipgre_tunnel_ioctl(struct net_device *dev,
- struct ifreq *ifr, int cmd)
+static int ipgre_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p,
+ int cmd)
{
- struct ip_tunnel_parm p;
int err;

- if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
- return -EFAULT;
-
if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
- if (p.iph.version != 4 || p.iph.protocol != IPPROTO_GRE ||
- p.iph.ihl != 5 || (p.iph.frag_off & htons(~IP_DF)) ||
- ((p.i_flags | p.o_flags) & (GRE_VERSION | GRE_ROUTING)))
+ if (p->iph.version != 4 || p->iph.protocol != IPPROTO_GRE ||
+ p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)) ||
+ ((p->i_flags | p->o_flags) & (GRE_VERSION | GRE_ROUTING)))
return -EINVAL;
}

- p.i_flags = gre_flags_to_tnl_flags(p.i_flags);
- p.o_flags = gre_flags_to_tnl_flags(p.o_flags);
+ p->i_flags = gre_flags_to_tnl_flags(p->i_flags);
+ p->o_flags = gre_flags_to_tnl_flags(p->o_flags);

- err = ip_tunnel_ioctl(dev, &p, cmd);
+ err = ip_tunnel_ctl(dev, p, cmd);
if (err)
return err;

if (cmd == SIOCCHGTUNNEL) {
struct ip_tunnel *t = netdev_priv(dev);

- t->parms.i_flags = p.i_flags;
- t->parms.o_flags = p.o_flags;
+ t->parms.i_flags = p->i_flags;
+ t->parms.o_flags = p->o_flags;

if (strcmp(dev->rtnl_link_ops->kind, "erspan"))
ipgre_link_update(dev, true);
}

- p.i_flags = gre_tnl_flags_to_gre_flags(p.i_flags);
- p.o_flags = gre_tnl_flags_to_gre_flags(p.o_flags);
-
- if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
- return -EFAULT;
-
+ p->i_flags = gre_tnl_flags_to_gre_flags(p->i_flags);
+ p->o_flags = gre_tnl_flags_to_gre_flags(p->o_flags);
return 0;
}

@@ -924,10 +916,11 @@ static const struct net_device_ops ipgre_netdev_ops = {
.ndo_stop = ipgre_close,
#endif
.ndo_start_xmit = ipgre_xmit,
- .ndo_do_ioctl = ipgre_tunnel_ioctl,
+ .ndo_do_ioctl = ip_tunnel_ioctl,
.ndo_change_mtu = ip_tunnel_change_mtu,
.ndo_get_stats64 = ip_tunnel_get_stats64,
.ndo_get_iflink = ip_tunnel_get_iflink,
+ .ndo_tunnel_ctl = ipgre_tunnel_ctl,
};

#define GRE_FEATURES (NETIF_F_SG | \
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index cd4b84310d929..f4f1d11eab502 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -860,7 +860,7 @@ static void ip_tunnel_update(struct ip_tunnel_net *itn,
netdev_state_change(dev);
}

-int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
+int ip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
{
int err = 0;
struct ip_tunnel *t = netdev_priv(dev);
@@ -960,6 +960,20 @@ int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
done:
return err;
}
+EXPORT_SYMBOL_GPL(ip_tunnel_ctl);
+
+int ip_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+ struct ip_tunnel_parm p;
+ int err;
+
+ if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
+ return -EFAULT;
+ err = dev->netdev_ops->ndo_tunnel_ctl(dev, &p, cmd);
+ if (!err && copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
+ return -EFAULT;
+ return err;
+}
EXPORT_SYMBOL_GPL(ip_tunnel_ioctl);

int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict)
diff --git a/net/ipv4/ip_vti.c b/net/ipv4/ip_vti.c
index 1b4e6f298648d..c8974360a99f4 100644
--- a/net/ipv4/ip_vti.c
+++ b/net/ipv4/ip_vti.c
@@ -378,38 +378,31 @@ static int vti4_err(struct sk_buff *skb, u32 info)
}

static int
-vti_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+vti_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
{
int err = 0;
- struct ip_tunnel_parm p;
-
- if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
- return -EFAULT;

if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
- if (p.iph.version != 4 || p.iph.protocol != IPPROTO_IPIP ||
- p.iph.ihl != 5)
+ if (p->iph.version != 4 || p->iph.protocol != IPPROTO_IPIP ||
+ p->iph.ihl != 5)
return -EINVAL;
}

- if (!(p.i_flags & GRE_KEY))
- p.i_key = 0;
- if (!(p.o_flags & GRE_KEY))
- p.o_key = 0;
+ if (!(p->i_flags & GRE_KEY))
+ p->i_key = 0;
+ if (!(p->o_flags & GRE_KEY))
+ p->o_key = 0;

- p.i_flags = VTI_ISVTI;
+ p->i_flags = VTI_ISVTI;

- err = ip_tunnel_ioctl(dev, &p, cmd);
+ err = ip_tunnel_ctl(dev, p, cmd);
if (err)
return err;

if (cmd != SIOCDELTUNNEL) {
- p.i_flags |= GRE_KEY;
- p.o_flags |= GRE_KEY;
+ p->i_flags |= GRE_KEY;
+ p->o_flags |= GRE_KEY;
}
-
- if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
- return -EFAULT;
return 0;
}

@@ -417,10 +410,11 @@ static const struct net_device_ops vti_netdev_ops = {
.ndo_init = vti_tunnel_init,
.ndo_uninit = ip_tunnel_uninit,
.ndo_start_xmit = vti_tunnel_xmit,
- .ndo_do_ioctl = vti_tunnel_ioctl,
+ .ndo_do_ioctl = ip_tunnel_ioctl,
.ndo_change_mtu = ip_tunnel_change_mtu,
.ndo_get_stats64 = ip_tunnel_get_stats64,
.ndo_get_iflink = ip_tunnel_get_iflink,
+ .ndo_tunnel_ctl = vti_tunnel_ctl,
};

static void vti_tunnel_setup(struct net_device *dev)
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index 2f01cf6fa0def..df663baf2516a 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -327,41 +327,29 @@ static bool ipip_tunnel_ioctl_verify_protocol(u8 ipproto)
}

static int
-ipip_tunnel_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+ipip_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd)
{
- int err = 0;
- struct ip_tunnel_parm p;
-
- if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
- return -EFAULT;
-
if (cmd == SIOCADDTUNNEL || cmd == SIOCCHGTUNNEL) {
- if (p.iph.version != 4 ||
- !ipip_tunnel_ioctl_verify_protocol(p.iph.protocol) ||
- p.iph.ihl != 5 || (p.iph.frag_off&htons(~IP_DF)))
+ if (p->iph.version != 4 ||
+ !ipip_tunnel_ioctl_verify_protocol(p->iph.protocol) ||
+ p->iph.ihl != 5 || (p->iph.frag_off & htons(~IP_DF)))
return -EINVAL;
}

- p.i_key = p.o_key = 0;
- p.i_flags = p.o_flags = 0;
- err = ip_tunnel_ioctl(dev, &p, cmd);
- if (err)
- return err;
-
- if (copy_to_user(ifr->ifr_ifru.ifru_data, &p, sizeof(p)))
- return -EFAULT;
-
- return 0;
+ p->i_key = p->o_key = 0;
+ p->i_flags = p->o_flags = 0;
+ return ip_tunnel_ctl(dev, p, cmd);
}

static const struct net_device_ops ipip_netdev_ops = {
.ndo_init = ipip_tunnel_init,
.ndo_uninit = ip_tunnel_uninit,
.ndo_start_xmit = ipip_tunnel_xmit,
- .ndo_do_ioctl = ipip_tunnel_ioctl,
+ .ndo_do_ioctl = ip_tunnel_ioctl,
.ndo_change_mtu = ip_tunnel_change_mtu,
.ndo_get_stats64 = ip_tunnel_get_stats64,
.ndo_get_iflink = ip_tunnel_get_iflink,
+ .ndo_tunnel_ctl = ipip_tunnel_ctl,
};

#define IPIP_FEATURES (NETIF_F_SG | \
--
2.26.2

Next message: Christoph Hellwig: "[PATCH 7/9] ipv6: stub out even more of addrconf_set_dstaddr if SIT is disabled"
Previous message: Christoph Hellwig: "[PATCH 2/9] ipv4: consolidate the VIFF_TUNNEL handling in ipmr_new_tunnel"
In reply to: Christoph Hellwig: "[PATCH 2/9] ipv4: consolidate the VIFF_TUNNEL handling in ipmr_new_tunnel"
Next in thread: Christoph Hellwig: "[PATCH 7/9] ipv6: stub out even more of addrconf_set_dstaddr if SIT is disabled"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]