On 7/9/18 4:25 AM, Sabrina Dubroca wrote:
> This aligns the addr_gen_mode sysctl with the expected behavior of the
> "all" variant.
>
> Fixes: d35a00b8e33d ("net/ipv6: allow sysctl to change link-local address
> generation mode")
> Suggested-by: David Ahern <[email protected]>
> Signed-off-by: Sabrina Dubroca <[email protected]>
> ---
> net/ipv6/addrconf.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
> index e89bca83e0e4..1659a6b3cf42 100644
> --- a/net/ipv6/addrconf.c
> +++ b/net/ipv6/addrconf.c
> @@ -5926,6 +5926,18 @@ static int addrconf_sysctl_addr_gen_mode(struct
> ctl_table *ctl, int write,
> idev->cnf.addr_gen_mode = new_val;
> addrconf_dev_config(idev->dev);
> }
> + } else if (&net->ipv6.devconf_all->addr_gen_mode == ctl->data) {
> + struct net_device *dev;
> +
> + net->ipv6.devconf_dflt->addr_gen_mode = new_val;
> + for_each_netdev(net, dev) {
> + idev = __in6_dev_get(dev);
> + if (idev &&
> + idev->cnf.addr_gen_mode != new_val) {
> + idev->cnf.addr_gen_mode = new_val;
> + addrconf_dev_config(idev->dev);
This call is adding a new LL address without removing the previous one:
# ip -6 addr sh dev eth2
4: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 state UP qlen 1000
inet6 2001:db8:2::4/64 scope global
valid_lft forever preferred_lft forever
inet6 fe80::e0:f9ff:fe45:6480/64 scope link
valid_lft forever preferred_lft forever
# sysctl -w net.ipv6.conf.eth2.addr_gen_mode=3
net.ipv6.conf.eth2.addr_gen_mode = 3
# ip -6 addr sh dev eth2
4: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 state UP qlen 1000
inet6 2001:db8:2::4/64 scope global
valid_lft forever preferred_lft forever
inet6 fe80::bc31:8009:270d:e019/64 scope link stable-privacy
valid_lft forever preferred_lft forever
inet6 fe80::e0:f9ff:fe45:6480/64 scope link
valid_lft forever preferred_lft forever
> + }
> + }
> }
>
> *((u32 *)ctl->data) = new_val;
>
