From: Patrick McHardy <redacted>
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 <redacted>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/netfilter/nf_nat_helper.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/net/netfilter/nf_nat_helper.c b/net/netfilter/nf_nat_helper.c
index 85e20a9..a7262ed 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. */
--
1.7.10.4