From 83619623929815a76fa7af49309d2cdfcf024fd3 Mon Sep 17 00:00:00 2001 From: Peter Oskolkov Date: Fri, 21 Sep 2018 11:17:16 -0700 Subject: [PATCH] net/ipfrag: let ip[6]frag_high_thresh in ns be higher than in init_net Currently, ip[6]frag_high_thresh sysctl values in new namespaces are hard-limited to those of the root/init ns. There are at least two use cases when it would be desirable to set the high_thresh values higher in a child namespace vs the global hard limit: - a security/ddos protection policy may lower the thresholds in the root/init ns but allow for a special exception in a child namespace - testing: a test running in a namespace may want to set these thresholds higher in its namespace than what is in the root/init ns The new behavior: # ip netns add testns # ip netns exec testns bash # sysctl -w net.ipv4.ipfrag_high_thresh=9000000 net.ipv4.ipfrag_high_thresh = 9000000 # sysctl net.ipv4.ipfrag_high_thresh net.ipv4.ipfrag_high_thresh = 9000000 # sysctl -w net.ipv6.ip6frag_high_thresh=9000000 net.ipv6.ip6frag_high_thresh = 9000000 # sysctl net.ipv6.ip6frag_high_thresh net.ipv6.ip6frag_high_thresh = 9000000 The old behavior: # ip netns add testns # ip netns exec testns bash # sysctl -w net.ipv4.ipfrag_high_thresh=9000000 net.ipv4.ipfrag_high_thresh = 9000000 # sysctl net.ipv4.ipfrag_high_thresh net.ipv4.ipfrag_high_thresh = 4194304 # sysctl -w net.ipv6.ip6frag_high_thresh=9000000 net.ipv6.ip6frag_high_thresh = 9000000 # sysctl net.ipv6.ip6frag_high_thresh net.ipv6.ip6frag_high_thresh = 4194304 Signed-off-by: Peter Oskolkov Signed-off-by: David S. Miller --- net/ieee802154/6lowpan/reassembly.c | 1 - net/ipv4/ip_fragment.c | 1 - net/ipv6/reassembly.c | 1 - 3 files changed, 3 deletions(-) diff --git a/net/ieee802154/6lowpan/reassembly.c b/net/ieee802154/6lowpan/reassembly.c index 09ffbf5ce8fa..d14226ecfde4 100644 --- a/net/ieee802154/6lowpan/reassembly.c +++ b/net/ieee802154/6lowpan/reassembly.c @@ -463,7 +463,6 @@ static int __net_init lowpan_frags_ns_sysctl_register(struct net *net) table[0].data = &ieee802154_lowpan->frags.high_thresh; table[0].extra1 = &ieee802154_lowpan->frags.low_thresh; - table[0].extra2 = &init_net.ieee802154_lowpan.frags.high_thresh; table[1].data = &ieee802154_lowpan->frags.low_thresh; table[1].extra2 = &ieee802154_lowpan->frags.high_thresh; table[2].data = &ieee802154_lowpan->frags.timeout; diff --git a/net/ipv4/ip_fragment.c b/net/ipv4/ip_fragment.c index 13f4d189e12b..9b0158fa431f 100644 --- a/net/ipv4/ip_fragment.c +++ b/net/ipv4/ip_fragment.c @@ -822,7 +822,6 @@ static int __net_init ip4_frags_ns_ctl_register(struct net *net) table[0].data = &net->ipv4.frags.high_thresh; table[0].extra1 = &net->ipv4.frags.low_thresh; - table[0].extra2 = &init_net.ipv4.frags.high_thresh; table[1].data = &net->ipv4.frags.low_thresh; table[1].extra2 = &net->ipv4.frags.high_thresh; table[2].data = &net->ipv4.frags.timeout; diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c index 536c1d172cba..5c3c92713096 100644 --- a/net/ipv6/reassembly.c +++ b/net/ipv6/reassembly.c @@ -554,7 +554,6 @@ static int __net_init ip6_frags_ns_sysctl_register(struct net *net) table[0].data = &net->ipv6.frags.high_thresh; table[0].extra1 = &net->ipv6.frags.low_thresh; - table[0].extra2 = &init_net.ipv6.frags.high_thresh; table[1].data = &net->ipv6.frags.low_thresh; table[1].extra2 = &net->ipv6.frags.high_thresh; table[2].data = &net->ipv6.frags.timeout;