[linux-yocto] [yocto-4.12][PATCH] ipv4: net namespace does not inherit network configurations

[Liwei Song]

Hi Bruce,

Could you help merge this patch to yocto-4.12?

Thanks,
Liwei.


On 11/28/2017 09:33 AM, Liwei Song wrote:
> From: yzhu1 <yanjun.zhu at windriver.com>
> 
> patch from https://lkml.org/lkml/2014/7/29/119
> 
> Ipv4 net namespace requires a similar logic change as commit a79ca223e029
> [ipv6: fix bad free of addrconf_init_net] introduces for newer kernels.
> 
> Since a net namespace is independent to another. That is, there
> is no any relationship between the net namespaces. So a new net
> namespace should not inherit network configurations from another
> net namespace including the host.
> 
> CC: Hong Zhiguo <honkiko at gmail.com>
> CC: David S. Miller <davem at davemloft.net>
> Signed-off-by: Zhu Yanjun <zyjzyj2000 at gmail.com>
> Signed-off-by: yzhu1 <yanjun.zhu at windriver.com>
> Signed-off-by: Liwei Song <liwei.song at windriver.com>
> ---
>  net/ipv4/devinet.c | 29 ++++++++++++-----------------
>  1 file changed, 12 insertions(+), 17 deletions(-)
> 
> diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
> index df14815a3b8c..a558a4c5004d 100644
> --- a/net/ipv4/devinet.c
> +++ b/net/ipv4/devinet.c
> @@ -2349,28 +2349,23 @@ static __net_init int devinet_init_net(struct net *net)
>  #endif
>  
>  	err = -ENOMEM;
> -	all = &ipv4_devconf;
> -	dflt = &ipv4_devconf_dflt;
> +	all = kmemdup(&ipv4_devconf, sizeof(ipv4_devconf), GFP_KERNEL);
> +	if (all == NULL)
> +		goto err_alloc_all;
>  
> -	if (!net_eq(net, &init_net)) {
> -		all = kmemdup(all, sizeof(ipv4_devconf), GFP_KERNEL);
> -		if (!all)
> -			goto err_alloc_all;
> -
> -		dflt = kmemdup(dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
> -		if (!dflt)
> -			goto err_alloc_dflt;
> +	dflt = kmemdup(&ipv4_devconf_dflt, sizeof(ipv4_devconf_dflt), GFP_KERNEL);
> +	if (dflt == NULL)
> +		goto err_alloc_dflt;
>  
>  #ifdef CONFIG_SYSCTL
> -		tbl = kmemdup(tbl, sizeof(ctl_forward_entry), GFP_KERNEL);
> -		if (!tbl)
> -			goto err_alloc_ctl;
> +	tbl = kmemdup(tbl, sizeof(ctl_forward_entry), GFP_KERNEL);
> +	if (tbl == NULL)
> +		goto err_alloc_ctl;
>  
> -		tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1];
> -		tbl[0].extra1 = all;
> -		tbl[0].extra2 = net;
> +	tbl[0].data = &all->data[IPV4_DEVCONF_FORWARDING - 1];
> +	tbl[0].extra1 = all;
> +	tbl[0].extra2 = net;
>  #endif
> -	}
>  
>  #ifdef CONFIG_SYSCTL
>  	err = __devinet_sysctl_register(net, "all", NETCONFA_IFINDEX_ALL, all);
>