[PATCH net-next] netns: correctly use per-netns ipv4 sysctl_tcp_mem
From: Huang Qiang <hidden>
Date: 2012-07-19 05:38:40
Subsystem:
networking [general], networking [sockets], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Kuniyuki Iwashima, Willem de Bruijn, Linus Torvalds
From: Yang Zhenzhang <redacted> Now, kernel allows each net namespace to independently set up its levels for tcp memory pressure thresholds. But it seems there is a bug, as using the following steps: [root@host socket]# lxc-start -n test -f config /bin/bash [root@net-test socket]# ip route add default via 192.168.58.2 [root@net-test socket]# echo 0 0 0 > /proc/sys/net/ipv4/tcp_mem [root@net-test socket]# scp root@192.168.58.174:/home/tcp_mem_test . and it still can transport the "tcp_mem_test" file which we hope it would not. It's because inet_init() (net/ipv4/af_inet.c)initialize the tcp_prot.sysctl_mem: tcp_prot.sysctl_mem = init_net.ipv4.sysctl_tcp_mem; So when the protocal is TCP, sk->sk_prot->sysctl_mem(following code) always use the ipv4 sysctl_tcp_mem of init_net namespace rather than it's own net namespace. This patch simply set "prot" equal to net->ipv4.sysctl_tcp_mem when the protocol type is TCP. Signed-off-by: Yang Zhenzhang <redacted> Signed-off-by: Huang Qiang <redacted> --- include/net/sock.h | 24 ++++++++++++++++-------- 1 files changed, 16 insertions(+), 8 deletions(-)
diff --git a/include/net/sock.h b/include/net/sock.h
index 88de092..61f4363 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h@@ -59,6 +59,7 @@ #include <linux/static_key.h> #include <linux/aio.h> #include <linux/sched.h> +#include <linux/in.h> #include <linux/filter.h> #include <linux/rculist_nulls.h>
@@ -1064,14 +1065,6 @@ static inline void sk_enter_memory_pressure(struct sock *sk) sk->sk_prot->enter_memory_pressure(sk); } -static inline long sk_prot_mem_limits(const struct sock *sk, int index) -{ - long *prot = sk->sk_prot->sysctl_mem; - if (mem_cgroup_sockets_enabled && sk->sk_cgrp) - prot = sk->sk_cgrp->sysctl_mem; - return prot[index]; -} - static inline void memcg_memory_allocated_add(struct cg_proto *prot, unsigned long amt, int *parent_status)
@@ -2155,6 +2148,21 @@ static inline void sk_change_net(struct sock *sk, struct net *net) sock_net_set(sk, hold_net(net)); } +static inline long sk_prot_mem_limits(const struct sock *sk, int index) +{ + long *prot = sk->sk_prot->sysctl_mem; + + if (sk->sk_protocol == IPPROTO_TCP) { + struct net *net = sock_net(sk); + prot = net->ipv4.sysctl_tcp_mem; + } + + if (mem_cgroup_sockets_enabled && sk->sk_cgrp) + prot = sk->sk_cgrp->sysctl_mem; + + return prot[index]; +} + static inline struct sock *skb_steal_sock(struct sk_buff *skb) { if (skb->sk) {
--
1.7.1