From deaa0a976b829af8a7886d8e2528a675cbe4dac8 Mon Sep 17 00:00:00 2001 From: Liping Zhang Date: Sun, 4 Jun 2017 19:17:34 +0800 Subject: [PATCH] netfilter: nf_ct_dccp/sctp: fix memory leak after netns cleanup After running the following commands for a while, kmemleak reported that "1879 new suspected memory leaks" happened: # while : ; do ip netns add test ip netns delete test done unreferenced object 0xffff88006342fa38 (size 1024): comm "ip", pid 15477, jiffies 4295982857 (age 957.836s) hex dump (first 32 bytes): b8 b0 4d a0 ff ff ff ff c0 34 c3 59 00 88 ff ff ..M......4.Y.... 04 00 00 00 a4 01 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [] kmemleak_alloc+0x4a/0xa0 [] __kmalloc_track_caller+0x150/0x300 [] kmemdup+0x20/0x50 [] dccp_init_net+0x8a/0x160 [nf_conntrack] [] nf_ct_l4proto_pernet_register_one+0x25/0x90 ... unreferenced object 0xffff88006342da58 (size 1024): comm "ip", pid 15477, jiffies 4295982857 (age 957.836s) hex dump (first 32 bytes): 10 b3 4d a0 ff ff ff ff 04 35 c3 59 00 88 ff ff ..M......5.Y.... 04 00 00 00 a4 01 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [] kmemleak_alloc+0x4a/0xa0 [] __kmalloc_track_caller+0x150/0x300 [] kmemdup+0x20/0x50 [] sctp_init_net+0x5d/0x130 [nf_conntrack] [] nf_ct_l4proto_pernet_register_one+0x25/0x90 ... This is because we forgot to implement the get_net_proto for sctp and dccp, so we won't invoke the nf_ct_unregister_sysctl to free the ctl_table when do netns cleanup. Also note, we will fail to register the sysctl for dccp/sctp either due to the lack of get_net_proto. Fixes: c51d39010a1b ("netfilter: conntrack: built-in support for DCCP") Fixes: a85406afeb3e ("netfilter: conntrack: built-in support for SCTP") Cc: Davide Caratti Signed-off-by: Liping Zhang Acked-by: Davide Caratti Acked-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_proto_dccp.c | 7 +++++++ net/netfilter/nf_conntrack_proto_sctp.c | 7 +++++++ 2 files changed, 14 insertions(+) diff --git a/net/netfilter/nf_conntrack_proto_dccp.c b/net/netfilter/nf_conntrack_proto_dccp.c index b553fdd..4707d99 100644 --- a/net/netfilter/nf_conntrack_proto_dccp.c +++ b/net/netfilter/nf_conntrack_proto_dccp.c @@ -872,6 +872,11 @@ static int dccp_init_net(struct net *net, u_int16_t proto) return dccp_kmemdup_sysctl_table(net, pn, dn); } +static struct nf_proto_net *dccp_get_net_proto(struct net *net) +{ + return &net->ct.nf_ct_proto.dccp.pn; +} + struct nf_conntrack_l4proto nf_conntrack_l4proto_dccp4 __read_mostly = { .l3proto = AF_INET, .l4proto = IPPROTO_DCCP, @@ -904,6 +909,7 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_dccp4 __read_mostly = { }, #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */ .init_net = dccp_init_net, + .get_net_proto = dccp_get_net_proto, }; EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_dccp4); @@ -939,5 +945,6 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_dccp6 __read_mostly = { }, #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */ .init_net = dccp_init_net, + .get_net_proto = dccp_get_net_proto, }; EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_dccp6); diff --git a/net/netfilter/nf_conntrack_proto_sctp.c b/net/netfilter/nf_conntrack_proto_sctp.c index 1c5b14a..4ed976f 100644 --- a/net/netfilter/nf_conntrack_proto_sctp.c +++ b/net/netfilter/nf_conntrack_proto_sctp.c @@ -786,6 +786,11 @@ static int sctp_init_net(struct net *net, u_int16_t proto) return sctp_kmemdup_sysctl_table(pn, sn); } +static struct nf_proto_net *sctp_get_net_proto(struct net *net) +{ + return &net->ct.nf_ct_proto.sctp.pn; +} + struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp4 __read_mostly = { .l3proto = PF_INET, .l4proto = IPPROTO_SCTP, @@ -819,6 +824,7 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp4 __read_mostly = { }, #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */ .init_net = sctp_init_net, + .get_net_proto = sctp_get_net_proto, }; EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_sctp4); @@ -855,5 +861,6 @@ struct nf_conntrack_l4proto nf_conntrack_l4proto_sctp6 __read_mostly = { #endif /* CONFIG_NF_CT_NETLINK_TIMEOUT */ #endif .init_net = sctp_init_net, + .get_net_proto = sctp_get_net_proto, }; EXPORT_SYMBOL_GPL(nf_conntrack_l4proto_sctp6); -- 2.7.4