From 64f3967c7aacbfa1f0614cdb1a23e3f7e76eb61b Mon Sep 17 00:00:00 2001 From: Liping Zhang Date: Mon, 17 Apr 2017 21:18:58 +0800 Subject: [PATCH] netfilter: ctnetlink: acquire ct->lock before operating nf_ct_seqadj We should acquire the ct->lock before accessing or modifying the nf_ct_seqadj, as another CPU may modify the nf_ct_seqadj at the same time during its packet proccessing. Signed-off-by: Liping Zhang Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_netlink.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 86deed6..78f8c9a 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -417,8 +417,7 @@ nla_put_failure: return -1; } -static int ctnetlink_dump_ct_seq_adj(struct sk_buff *skb, - const struct nf_conn *ct) +static int ctnetlink_dump_ct_seq_adj(struct sk_buff *skb, struct nf_conn *ct) { struct nf_conn_seqadj *seqadj = nfct_seqadj(ct); struct nf_ct_seqadj *seq; @@ -426,15 +425,20 @@ static int ctnetlink_dump_ct_seq_adj(struct sk_buff *skb, if (!(ct->status & IPS_SEQ_ADJUST) || !seqadj) return 0; + spin_lock_bh(&ct->lock); seq = &seqadj->seq[IP_CT_DIR_ORIGINAL]; if (dump_ct_seq_adj(skb, seq, CTA_SEQ_ADJ_ORIG) == -1) - return -1; + goto err; seq = &seqadj->seq[IP_CT_DIR_REPLY]; if (dump_ct_seq_adj(skb, seq, CTA_SEQ_ADJ_REPLY) == -1) - return -1; + goto err; + spin_unlock_bh(&ct->lock); return 0; +err: + spin_unlock_bh(&ct->lock); + return -1; } static int ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct) @@ -1637,11 +1641,12 @@ ctnetlink_change_seq_adj(struct nf_conn *ct, if (!seqadj) return 0; + spin_lock_bh(&ct->lock); if (cda[CTA_SEQ_ADJ_ORIG]) { ret = change_seq_adj(&seqadj->seq[IP_CT_DIR_ORIGINAL], cda[CTA_SEQ_ADJ_ORIG]); if (ret < 0) - return ret; + goto err; set_bit(IPS_SEQ_ADJUST_BIT, &ct->status); } @@ -1650,12 +1655,16 @@ ctnetlink_change_seq_adj(struct nf_conn *ct, ret = change_seq_adj(&seqadj->seq[IP_CT_DIR_REPLY], cda[CTA_SEQ_ADJ_REPLY]); if (ret < 0) - return ret; + goto err; set_bit(IPS_SEQ_ADJUST_BIT, &ct->status); } + spin_unlock_bh(&ct->lock); return 0; +err: + spin_unlock_bh(&ct->lock); + return ret; } static int -- 2.7.4