From: Patrick McHardy Date: Sun, 28 Jul 2013 20:54:09 +0000 (+0200) Subject: netfilter: nf_nat: fix locking in nf_nat_seq_adjust() X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=0658cdc8f3babb4a441f5a803a0b644fafcbf9ef;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git netfilter: nf_nat: fix locking in nf_nat_seq_adjust() nf_nat_seq_adjust() needs to grab nf_nat_seqofs_lock to protect against concurrent changes to the sequence adjustment data. Signed-off-by: Patrick McHardy Signed-off-by: Pablo Neira Ayuso --- diff --git a/net/netfilter/nf_nat_helper.c b/net/netfilter/nf_nat_helper.c index 85e20a919081..a7262ed055c6 100644 --- a/net/netfilter/nf_nat_helper.c +++ b/net/netfilter/nf_nat_helper.c @@ -373,6 +373,7 @@ nf_nat_seq_adjust(struct sk_buff *skb, s16 seqoff, ackoff; struct nf_conn_nat *nat = nfct_nat(ct); struct nf_nat_seq *this_way, *other_way; + int res; dir = CTINFO2DIR(ctinfo); @@ -383,6 +384,7 @@ nf_nat_seq_adjust(struct sk_buff *skb, return 0; tcph = (void *)skb->data + protoff; + spin_lock_bh(&nf_nat_seqofs_lock); if (after(ntohl(tcph->seq), this_way->correction_pos)) seqoff = this_way->offset_after; else @@ -407,7 +409,10 @@ nf_nat_seq_adjust(struct sk_buff *skb, tcph->seq = newseq; tcph->ack_seq = newack; - return nf_nat_sack_adjust(skb, protoff, tcph, ct, ctinfo); + res = nf_nat_sack_adjust(skb, protoff, tcph, ct, ctinfo); + spin_unlock_bh(&nf_nat_seqofs_lock); + + return res; } /* Setup NAT on this expected conntrack so it follows master. */