From 4cfecb7fc742888bf31bd49cfa16dd6eb42641e6 Mon Sep 17 00:00:00 2001 From: Jiri Pirko Date: Fri, 13 Oct 2023 14:10:23 +0200 Subject: [PATCH] net: treat possible_net_t net pointer as an RCU one and add read_pnet_rcu() [ Upstream commit 2034d90ae41ae93e30d492ebcf1f06f97a9cfba6 ] Make the net pointer stored in possible_net_t structure annotated as an RCU pointer. Change the access helpers to treat it as such. Introduce read_pnet_rcu() helper to allow caller to dereference the net pointer under RCU read lock. Signed-off-by: Jiri Pirko Reviewed-by: Simon Horman Signed-off-by: David S. Miller Stable-dep-of: 71b8471c93fa ("ipv4: use RCU protection in ipv4_default_advmss()") Signed-off-by: Sasha Levin --- include/net/net_namespace.h | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 1befad79a673..b767bdcd9e12 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -369,21 +369,30 @@ static inline void put_net_track(struct net *net, netns_tracker *tracker) typedef struct { #ifdef CONFIG_NET_NS - struct net *net; + struct net __rcu *net; #endif } possible_net_t; static inline void write_pnet(possible_net_t *pnet, struct net *net) { #ifdef CONFIG_NET_NS - pnet->net = net; + rcu_assign_pointer(pnet->net, net); #endif } static inline struct net *read_pnet(const possible_net_t *pnet) { #ifdef CONFIG_NET_NS - return pnet->net; + return rcu_dereference_protected(pnet->net, true); +#else + return &init_net; +#endif +} + +static inline struct net *read_pnet_rcu(possible_net_t *pnet) +{ +#ifdef CONFIG_NET_NS + return rcu_dereference(pnet->net); #else return &init_net; #endif