Get it ready for constant netdev->dev_addr.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Although if_info_size is assigned, it has not been used. And the variable
should also be deleted.

The clang_analyzer complains as follows:

net/core/rtnetlink.c:3806: warning:

Although the value stored to 'if_info_size' is used in the enclosing
expression, the value is never actually read from 'if_info_size'.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: luo penghao <luo.penghao@zte.com.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Make use of netdev helper functions to improve code readability.
Replace 'dev->priv_flags & IFF_EBRIDGE' with netif_is_bridge_master(dev).

Signed-off-by: Kyungrok Chung <acadx0@gmail.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

rtnl_fill_statsinfo() is filling skb with one mandatory if_stats_msg structure.

nlmsg_put(skb, pid, seq, type, sizeof(struct if_stats_msg), flags);

But if_nlmsg_stats_size() never considered the needed storage.

This bug did not show up because alloc_skb(X) allocates skb with
extra tailroom, because of added alignments. This could very well
be changed in the future to have deterministic behavior.

Fixes: 10c9ead9f3c6 ("rtnetlink: add new RTM_GETSTATS message to dump link stats")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Roopa Prabhu <roopa@nvidia.com>
Acked-by: Roopa Prabhu <roopa@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It no need barrier when assigning a NULL value to an RCU protected
pointer. So use RCU_INIT_POINTER() instead for more fast.

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wwan/mhi_wwan_mbim.c - drop the extra arg.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Currently when device is moved between network namespaces using
RTM_NEWLINK message type and one of netns attributes (FLA_NET_NS_PID,
IFLA_NET_NS_FD, IFLA_TARGET_NETNSID) but w/o specifying IFLA_IFNAME, and
target namespace already has device with same name, userspace will get
EINVAL what is confusing and makes debugging harder.

Fix it so that userspace gets more appropriate EEXIST instead what makes
debugging much easier.

Before:

  # ./ifname.sh
  + ip netns add ns0
  + ip netns exec ns0 ip link add l0 type dummy
  + ip netns exec ns0 ip link show l0
  8: l0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether 66:90:b5:d5:78:69 brd ff:ff:ff:ff:ff:ff
  + ip link add l0 type dummy
  + ip link show l0
  10: l0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether 6e:c6:1f:15:20:8d brd ff:ff:ff:ff:ff:ff
  + ip link set l0 netns ns0
  RTNETLINK answers: Invalid argument

After:

  # ./ifname.sh
  + ip netns add ns0
  + ip netns exec ns0 ip link add l0 type dummy
  + ip netns exec ns0 ip link show l0
  8: l0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether 1e:4a:72:e3:e3:8f brd ff:ff:ff:ff:ff:ff
  + ip link add l0 type dummy
  + ip link show l0
  10: l0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
      link/ether f2:fc:fe:2b:7d:a6 brd ff:ff:ff:ff:ff:ff
  + ip link set l0 netns ns0
  RTNETLINK answers: File exists

The problem is that do_setlink() passes its `char *ifname` argument,
that it gets from a caller, to __dev_change_net_namespace() as is (as
`const char *pat`), but semantics of ifname and pat can be different.

For example, __rtnl_newlink() does this:

net/core/rtnetlink.c
    3270	char ifname[IFNAMSIZ];
     ...
    3286	if (tb[IFLA_IFNAME])
    3287		nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ);
    3288	else
    3289		ifname[0] = '\0';
     ...
    3364	if (dev) {
     ...
    3394		return do_setlink(skb, dev, ifm, extack, tb, ifname, status);
    3395	}

, i.e. do_setlink() gets ifname pointer that is always valid no matter
if user specified IFLA_IFNAME or not and then do_setlink() passes this
ifname pointer as is to __dev_change_net_namespace() as pat argument.

But the pat (pattern) in __dev_change_net_namespace() is used as:

net/core/dev.c
   11198	err = -EEXIST;
   11199	if (__dev_get_by_name(net, dev->name)) {
   11200		/* We get here if we can't use the current device name */
   11201		if (!pat)
   11202			goto out;
   11203		err = dev_get_valid_name(net, dev, pat);
   11204		if (err < 0)
   11205			goto out;
   11206	}

As the result the `goto out` path on line 11202 is neven taken and
instead of returning EEXIST defined on line 11198,
__dev_change_net_namespace() returns an error from dev_get_valid_name()
and this, in turn, will be EINVAL for ifname[0] = '\0' set earlier.

Fixes: d8a5ec672768 ("[NET]: netlink support for moving devices between network namespaces.")
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently there's support for filtering neighbours/links for interfaces
which have a specific master device (using the IFLA_MASTER/NDA_MASTER
attributes).

This patch adds support for filtering interfaces/neighbours dump for
interfaces that *don't* have a master.

Signed-off-by: Lahav Schlesinger <lschlesinger@drivenets.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20210810090658.2778960-1-lschlesinger@drivenets.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Pass extack arg to validate_linkmsg and validate_link_af callbacks.
If a netlink attribute has a reject_message, use the extended ack
mechanism to carry the message back to user space.

Signed-off-by: Rocco Yue <rocco.yue@mediatek.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>