Subject: Re: [PATCH net-next] ip6_vti: fix memleak on netns dismantle

From: Simon Horman <[email-masked]>
Date: Tue, 16 Apr 2024 15:03:50 +0100

+ Steffen Klassert, Herbert Xu, David Ahern

On Mon, Apr 15, 2024 at 02:23:44PM +0200, Florian Westphal wrote:
> kmemleak reports net_device resources are no longer released, restore
> needs_free_netdev toggle.  Sample backtrace:
> 
> unreferenced object 0xffff88810874f000 (size 4096): [..]
>     [<00000000a2b8af8b>] __kmalloc_node+0x209/0x290
>     [<0000000040b0a1a9>] alloc_netdev_mqs+0x58/0x470
>     [<00000000b4be1e78>] vti6_init_net+0x94/0x230
>     [<000000008830c1ea>] ops_init+0x32/0xc0
>     [<000000006a26fa8f>] setup_net+0x134/0x2e0
> [..]
> 
> Cc: Breno Leitao <[email-masked]>
> Fixes: a9b2d55a8f1e ("ip6_vti: Do not use custom stat allocator")
> Signed-off-by: Florian Westphal <[email-masked]>

Reviewed-by: Simon Horman <[email-masked]>

> ---
>  net/ipv6/ip6_vti.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c
> index 4d68a0777b0c..78344cf3867e 100644
> --- a/net/ipv6/ip6_vti.c
> +++ b/net/ipv6/ip6_vti.c
> @@ -901,6 +901,7 @@ static void vti6_dev_setup(struct net_device *dev)
>  {
>  	dev->netdev_ops = &vti6_netdev_ops;
>  	dev->header_ops = &ip_tunnel_header_ops;
> +	dev->needs_free_netdev = true;
>  
>  	dev->pcpu_stat_type = NETDEV_PCPU_STAT_TSTATS;
>  	dev->type = ARPHRD_TUNNEL6;
> -- 
> 2.43.2
> 
>