From 2e9589ff809e9232f689acd51da73390e135146a Mon Sep 17 00:00:00 2001 From: xu xin Date: Wed, 26 Jan 2022 07:10:58 +0000 Subject: [PATCH] ipv4: Namespaceify min_adv_mss sysctl knob Different netns has different requirement on the setting of min_adv_mss sysctl which the advertised MSS will be never lower than. Enable min_adv_mss to be configured per network namespace. Signed-off-by: xu xin Signed-off-by: David S. Miller --- include/net/netns/ipv4.h | 1 + net/ipv4/route.c | 21 +++++++++++---------- 2 files changed, 12 insertions(+), 10 deletions(-) diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h index 94568e0..f068786 100644 --- a/include/net/netns/ipv4.h +++ b/include/net/netns/ipv4.h @@ -83,6 +83,7 @@ struct netns_ipv4 { u32 ip_rt_min_pmtu; int ip_rt_mtu_expires; + int ip_rt_min_advmss; struct local_ports ip_local_ports; diff --git a/net/ipv4/route.c b/net/ipv4/route.c index ff6f91c..e42e283 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -112,14 +112,13 @@ #define DEFAULT_MIN_PMTU (512 + 20 + 20) #define DEFAULT_MTU_EXPIRES (10 * 60 * HZ) - +#define DEFAULT_MIN_ADVMSS 256 static int ip_rt_max_size; static int ip_rt_redirect_number __read_mostly = 9; static int ip_rt_redirect_load __read_mostly = HZ / 50; static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1)); static int ip_rt_error_cost __read_mostly = HZ; static int ip_rt_error_burst __read_mostly = 5 * HZ; -static int ip_rt_min_advmss __read_mostly = 256; static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT; @@ -1298,9 +1297,10 @@ static void set_class_tag(struct rtable *rt, u32 tag) static unsigned int ipv4_default_advmss(const struct dst_entry *dst) { + struct net *net = dev_net(dst->dev); unsigned int header_size = sizeof(struct tcphdr) + sizeof(struct iphdr); unsigned int advmss = max_t(unsigned int, ipv4_mtu(dst) - header_size, - ip_rt_min_advmss); + net->ipv4.ip_rt_min_advmss); return min(advmss, IPV4_MAX_PMTU - header_size); } @@ -3535,13 +3535,6 @@ static struct ctl_table ipv4_route_table[] = { .mode = 0644, .proc_handler = proc_dointvec, }, - { - .procname = "min_adv_mss", - .data = &ip_rt_min_advmss, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, { } }; @@ -3569,6 +3562,13 @@ static struct ctl_table ipv4_route_netns_table[] = { .mode = 0644, .proc_handler = proc_dointvec_jiffies, }, + { + .procname = "min_adv_mss", + .data = &init_net.ipv4.ip_rt_min_advmss, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, { }, }; @@ -3631,6 +3631,7 @@ static __net_init int netns_ip_rt_init(struct net *net) /* Set default value for namespaceified sysctls */ net->ipv4.ip_rt_min_pmtu = DEFAULT_MIN_PMTU; net->ipv4.ip_rt_mtu_expires = DEFAULT_MTU_EXPIRES; + net->ipv4.ip_rt_min_advmss = DEFAULT_MIN_ADVMSS; return 0; } -- 2.7.4