netfilter: nf_nat: change sequence number adjustments to 32 bits

Using 16 bits is too small, when many adjustments happen the offsets might
overflow and break the connection.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

4 files changed, 6 insertions, 6 deletions

diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h
index f4bbf2cd22d8..655d5d198d49 100644
--- a/include/linux/netfilter.h
+++ b/include/linux/netfilter.h
@@ -330,7 +330,7 @@ extern struct nfq_ct_hook __rcu *nfq_ct_hook;
 
 struct nfq_ct_nat_hook {
         void (*seq_adjust)(struct sk_buff *skb, struct nf_conn *ct,
-                           u32 ctinfo, int off);
+                           u32 ctinfo, s32 off);
 };
 extern struct nfq_ct_nat_hook __rcu *nfq_ct_nat_hook;
 #else
diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h
index 939aced35a02..e5eb8b62538c 100644
--- a/include/net/netfilter/nf_conntrack.h
+++ b/include/net/netfilter/nf_conntrack.h
@@ -234,7 +234,7 @@ static inline bool nf_ct_kill(struct nf_conn *ct)
 }
 
 /* These are for NAT.  Icky. */
-extern s16 (*nf_ct_nat_offset)(const struct nf_conn *ct,
+extern s32 (*nf_ct_nat_offset)(const struct nf_conn *ct,
                                enum ip_conntrack_dir dir,
                                u32 seq);
 
diff --git a/include/net/netfilter/nf_nat.h b/include/net/netfilter/nf_nat.h
index ad14a799fd2e..e2441413675c 100644
--- a/include/net/netfilter/nf_nat.h
+++ b/include/net/netfilter/nf_nat.h
@@ -19,7 +19,7 @@ struct nf_nat_seq {
         u_int32_t correction_pos;
 
         /* sequence number offset before and after last modification */
-        int16_t offset_before, offset_after;
+        int32_t offset_before, offset_after;
 };
 
 #include <linux/list.h>
diff --git a/include/net/netfilter/nf_nat_helper.h b/include/net/netfilter/nf_nat_helper.h
index b4d6bfc2af03..194c34794923 100644
--- a/include/net/netfilter/nf_nat_helper.h
+++ b/include/net/netfilter/nf_nat_helper.h
@@ -41,7 +41,7 @@ extern int nf_nat_mangle_udp_packet(struct sk_buff *skb,
 
 extern void nf_nat_set_seq_adjust(struct nf_conn *ct,
                                   enum ip_conntrack_info ctinfo,
-                                  __be32 seq, s16 off);
+                                  __be32 seq, s32 off);
 extern int nf_nat_seq_adjust(struct sk_buff *skb,
                              struct nf_conn *ct,
                              enum ip_conntrack_info ctinfo,
@@ -56,11 +56,11 @@ extern int (*nf_nat_seq_adjust_hook)(struct sk_buff *skb,
 extern void nf_nat_follow_master(struct nf_conn *ct,
                                  struct nf_conntrack_expect *this);
 
-extern s16 nf_nat_get_offset(const struct nf_conn *ct,
+extern s32 nf_nat_get_offset(const struct nf_conn *ct,
                              enum ip_conntrack_dir dir,
                              u32 seq);
 
 extern void nf_nat_tcp_seq_adjust(struct sk_buff *skb, struct nf_conn *ct,
-                                  u32 dir, int off);
+                                  u32 dir, s32 off);
 
 #endif