[NETFILTER]: nf_conntrack_ipv4: fix module parameter compatibility

Some users do "modprobe ip_conntrack hashsize=...". Since we have the
module aliases this loads nf_conntrack_ipv4 and nf_conntrack, the
hashsize parameter is unknown for nf_conntrack_ipv4 however and makes
it fail.

Allow to specify hashsize= for both nf_conntrack and nf_conntrack_ipv4.

Note: the nf_conntrack message in the ringbuffer will display an
incorrect hashsize since nf_conntrack is first pulled in as a
dependency and calculates the size itself, then it gets changed
through a call to nf_conntrack_set_hashsize().
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/netfilter/nf_conntrack.h

@@ -249,6 +249,7 @@ static inline int nf_ct_is_untracked(const struct sk_buff *skb)
 	return (skb->nfct == &nf_conntrack_untracked.ct_general);
 }
 
+extern int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp);
 extern unsigned int nf_conntrack_htable_size;
 extern int nf_conntrack_checksum;
 extern atomic_t nf_conntrack_count;

net/ipv4/netfilter/nf_conntrack_l3proto_ipv4.c

@@ -419,6 +419,9 @@ struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv4 __read_mostly = {
 	.me		 = THIS_MODULE,
 };
 
+module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint,
+		  &nf_conntrack_htable_size, 0600);
+
 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET));
 MODULE_ALIAS("ip_conntrack");
 MODULE_LICENSE("GPL");

net/netfilter/nf_conntrack_core.c

@@ -1016,7 +1016,7 @@ struct hlist_head *nf_ct_alloc_hashtable(int *sizep, int *vmalloced)
 }
 EXPORT_SYMBOL_GPL(nf_ct_alloc_hashtable);
 
-int set_hashsize(const char *val, struct kernel_param *kp)
+int nf_conntrack_set_hashsize(const char *val, struct kernel_param *kp)
 {
 	int i, bucket, hashsize, vmalloced;
 	int old_vmalloced, old_size;
@@ -1063,8 +1063,9 @@ int set_hashsize(const char *val, struct kernel_param *kp)
 	nf_ct_free_hashtable(old_hash, old_vmalloced, old_size);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(nf_conntrack_set_hashsize);
 
-module_param_call(hashsize, set_hashsize, param_get_uint,
+module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint,
 		  &nf_conntrack_htable_size, 0600);
 
 int __init nf_conntrack_init(void)