diff --git a/net/netfilter/nf_conntrack_amanda.c b/net/netfilter/nf_conntrack_amanda.c
index d14585a..ddfac99 100644
--- a/net/netfilter/nf_conntrack_amanda.c
+++ b/net/netfilter/nf_conntrack_amanda.c
@@ -53,7 +53,7 @@
 };
 
 static struct {
-	char			*string;
+	const char		*string;
 	size_t			len;
 	struct ts_config	*ts;
 } search[] __read_mostly = {
diff --git a/net/netfilter/nf_conntrack_ftp.c b/net/netfilter/nf_conntrack_ftp.c
index 7eff876bb..87ca39b 100644
--- a/net/netfilter/nf_conntrack_ftp.c
+++ b/net/netfilter/nf_conntrack_ftp.c
@@ -350,8 +350,9 @@
 		enum ip_conntrack_info ctinfo)
 {
 	unsigned int dataoff, datalen;
-	struct tcphdr _tcph, *th;
-	char *fb_ptr;
+	const struct tcphdr *th;
+	struct tcphdr _tcph;
+	const char *fb_ptr;
 	int ret;
 	u32 seq;
 	int dir = CTINFO2DIR(ctinfo);
diff --git a/net/netfilter/nf_conntrack_helper.c b/net/netfilter/nf_conntrack_helper.c
index e350f56..7d1b117 100644
--- a/net/netfilter/nf_conntrack_helper.c
+++ b/net/netfilter/nf_conntrack_helper.c
@@ -126,7 +126,7 @@
 {
 	struct nf_conntrack_tuple_hash *h;
 	struct nf_conntrack_expect *exp;
-	struct hlist_node *n, *next;
+	const struct hlist_node *n, *next;
 	unsigned int i;
 
 	mutex_lock(&nf_ct_helper_mutex);
diff --git a/net/netfilter/nf_conntrack_irc.c b/net/netfilter/nf_conntrack_irc.c
index 02f21cb..1b1226d 100644
--- a/net/netfilter/nf_conntrack_irc.c
+++ b/net/netfilter/nf_conntrack_irc.c
@@ -50,7 +50,7 @@
 module_param(dcc_timeout, uint, 0400);
 MODULE_PARM_DESC(dcc_timeout, "timeout on for unestablished DCC channels");
 
-static const char *dccprotos[] = {
+static const char *const dccprotos[] = {
 	"SEND ", "CHAT ", "MOVE ", "TSEND ", "SCHAT "
 };
 
@@ -65,7 +65,7 @@
  *	ad_beg_p	returns pointer to first byte of addr data
  *	ad_end_p	returns pointer to last byte of addr data
  */
-static int parse_dcc(char *data, char *data_end, u_int32_t *ip,
+static int parse_dcc(char *data, const char *data_end, u_int32_t *ip,
 		     u_int16_t *port, char **ad_beg_p, char **ad_end_p)
 {
 	/* at least 12: "AAAAAAAA P\1\n" */
@@ -93,9 +93,11 @@
 		struct nf_conn *ct, enum ip_conntrack_info ctinfo)
 {
 	unsigned int dataoff;
-	struct iphdr *iph;
-	struct tcphdr _tcph, *th;
-	char *data, *data_limit, *ib_ptr;
+	const struct iphdr *iph;
+	const struct tcphdr *th;
+	struct tcphdr _tcph;
+	const char *data_limit;
+	char *data, *ib_ptr;
 	int dir = CTINFO2DIR(ctinfo);
 	struct nf_conntrack_expect *exp;
 	struct nf_conntrack_tuple *tuple;
@@ -159,7 +161,7 @@
 			/* we have at least
 			 * (19+MINMATCHLEN)-5-dccprotos[i].matchlen bytes valid
 			 * data left (== 14/13 bytes) */
-			if (parse_dcc((char *)data, data_limit, &dcc_ip,
+			if (parse_dcc(data, data_limit, &dcc_ip,
 				       &dcc_port, &addr_beg_p, &addr_end_p)) {
 				pr_debug("unable to parse dcc command\n");
 				continue;