netdev - Re: [PATCH net-next v5 1/6] geneve: rely on rtnl lock in geneve_offload_rx

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <22ec7ed6-9c38-4f81-9ec4-024da12b8710@blackwall.org>
Date: Wed, 18 Jun 2025 18:14:06 +0300
From: Nikolay Aleksandrov <razor@...ckwall.org>
To: Stanislav Fomichev <stfomichev@...il.com>, netdev@...r.kernel.org
Cc: davem@...emloft.net, edumazet@...gle.com, kuba@...nel.org,
 pabeni@...hat.com, skalluru@...vell.com, manishc@...vell.com,
 andrew+netdev@...n.ch, michael.chan@...adcom.com, pavan.chebbi@...adcom.com,
 ajit.khaparde@...adcom.com, sriharsha.basavapatna@...adcom.com,
 somnath.kotur@...adcom.com, anthony.l.nguyen@...el.com,
 przemyslaw.kitszel@...el.com, tariqt@...dia.com, saeedm@...dia.com,
 louis.peens@...igine.com, shshaikh@...vell.com,
 GR-Linux-NIC-Dev@...vell.com, ecree.xilinx@...il.com, horms@...nel.org,
 dsahern@...nel.org, shuah@...nel.org, tglx@...utronix.de, mingo@...nel.org,
 ruanjinjie@...wei.com, idosch@...dia.com, petrm@...dia.com,
 kuniyu@...gle.com, sdf@...ichev.me, linux-kernel@...r.kernel.org,
 intel-wired-lan@...ts.osuosl.org, linux-rdma@...r.kernel.org,
 oss-drivers@...igine.com, linux-net-drivers@....com,
 linux-kselftest@...r.kernel.org, leon@...nel.org
Subject: Re: [PATCH net-next v5 1/6] geneve: rely on rtnl lock in
 geneve_offload_rx_ports

On 6/16/25 19:21, Stanislav Fomichev wrote:
> udp_tunnel_push_rx_port will grab mutex in the next patch so
> we can't use rcu. geneve_offload_rx_ports is called
> from geneve_netdevice_event for NETDEV_UDP_TUNNEL_PUSH_INFO and
> NETDEV_UDP_TUNNEL_DROP_INFO which both have ASSERT_RTNL.
> Entries are added to and removed from the sock_list under rtnl
> lock as well (when adding or removing a tunneling device).
> 
> Signed-off-by: Stanislav Fomichev <stfomichev@...il.com>
> ---
>  drivers/net/geneve.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
> index ffc15a432689..9efedc6758bf 100644
> --- a/drivers/net/geneve.c
> +++ b/drivers/net/geneve.c
> @@ -41,6 +41,7 @@ MODULE_PARM_DESC(log_ecn_error, "Log packets received with corrupted ECN");
>  /* per-network namespace private data for this module */
>  struct geneve_net {
>  	struct list_head	geneve_list;
> +	/* sock_list is protected by rtnl lock */
>  	struct list_head	sock_list;
>  };
>  
> @@ -1179,8 +1180,9 @@ static void geneve_offload_rx_ports(struct net_device *dev, bool push)
>  	struct geneve_net *gn = net_generic(net, geneve_net_id);
>  	struct geneve_sock *gs;
>  
> -	rcu_read_lock();
> -	list_for_each_entry_rcu(gs, &gn->sock_list, list) {
> +	ASSERT_RTNL();
> +
> +	list_for_each_entry(gs, &gn->sock_list, list) {
>  		if (push) {
>  			udp_tunnel_push_rx_port(dev, gs->sock,
>  						UDP_TUNNEL_TYPE_GENEVE);
> @@ -1189,7 +1191,6 @@ static void geneve_offload_rx_ports(struct net_device *dev, bool push)
>  						UDP_TUNNEL_TYPE_GENEVE);
>  		}
>  	}
> -	rcu_read_unlock();
>  }
>  
>  /* Initialize the device structure. */

Reviewed-by: Nikolay Aleksandrov <razor@...ckwall.org>