[NETFILTER]: nf_conntrack: more sanity checks in protocol registration/unregistration
Add some more sanity checks when registering/unregistering l3/l4 protocols.
Signed-off-by: Martin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/include/net/netfilter/nf_conntrack_l3proto.h b/include/net/netfilter/nf_conntrack_l3proto.h
index ffe23a1..11b4b29 100644
--- a/include/net/netfilter/nf_conntrack_l3proto.h
+++ b/include/net/netfilter/nf_conntrack_l3proto.h
@@ -86,7 +86,7 @@
/* Protocol registration. */
extern int nf_conntrack_l3proto_register(struct nf_conntrack_l3proto *proto);
-extern void nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto);
+extern int nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto);
extern struct nf_conntrack_l3proto *
nf_ct_l3proto_find_get(u_int16_t l3proto);
diff --git a/include/net/netfilter/nf_conntrack_l4proto.h b/include/net/netfilter/nf_conntrack_l4proto.h
index 0c6babd..5193e48 100644
--- a/include/net/netfilter/nf_conntrack_l4proto.h
+++ b/include/net/netfilter/nf_conntrack_l4proto.h
@@ -102,7 +102,7 @@
/* Protocol registration. */
extern int nf_conntrack_l4proto_register(struct nf_conntrack_l4proto *proto);
-extern void nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *proto);
+extern int nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *proto);
/* Generic netlink helpers */
extern int nf_ct_port_tuple_to_nfattr(struct sk_buff *skb,
diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c
index 441a647..73615d3 100644
--- a/net/netfilter/nf_conntrack_core.c
+++ b/net/netfilter/nf_conntrack_core.c
@@ -1198,7 +1198,7 @@
/* Don't NEED lock here, but good form anyway. */
write_lock_bh(&nf_conntrack_lock);
- for (i = 0; i < PF_MAX; i++)
+ for (i = 0; i < AF_MAX; i++)
nf_ct_l3protos[i] = &nf_conntrack_l3proto_generic;
write_unlock_bh(&nf_conntrack_lock);
diff --git a/net/netfilter/nf_conntrack_proto.c b/net/netfilter/nf_conntrack_proto.c
index 330b9ac..a6a3b1d 100644
--- a/net/netfilter/nf_conntrack_proto.c
+++ b/net/netfilter/nf_conntrack_proto.c
@@ -28,7 +28,7 @@
#include <net/netfilter/nf_conntrack_core.h>
struct nf_conntrack_l4proto **nf_ct_protos[PF_MAX] __read_mostly;
-struct nf_conntrack_l3proto *nf_ct_l3protos[PF_MAX] __read_mostly;
+struct nf_conntrack_l3proto *nf_ct_l3protos[AF_MAX] __read_mostly;
struct nf_conntrack_l4proto *
__nf_ct_l4proto_find(u_int16_t l3proto, u_int8_t l4proto)
@@ -128,21 +128,40 @@
{
int ret = 0;
- write_lock_bh(&nf_conntrack_lock);
- if (nf_ct_l3protos[proto->l3proto] != &nf_conntrack_l3proto_generic) {
+ if (proto->l3proto >= AF_MAX) {
ret = -EBUSY;
goto out;
}
- nf_ct_l3protos[proto->l3proto] = proto;
-out:
- write_unlock_bh(&nf_conntrack_lock);
+ write_lock_bh(&nf_conntrack_lock);
+ if (nf_ct_l3protos[proto->l3proto] != &nf_conntrack_l3proto_generic) {
+ ret = -EBUSY;
+ goto out_unlock;
+ }
+ nf_ct_l3protos[proto->l3proto] = proto;
+
+out_unlock:
+ write_unlock_bh(&nf_conntrack_lock);
+out:
return ret;
}
-void nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto)
+int nf_conntrack_l3proto_unregister(struct nf_conntrack_l3proto *proto)
{
+ int ret = 0;
+
+ if (proto->l3proto >= AF_MAX) {
+ ret = -EBUSY;
+ goto out;
+ }
+
write_lock_bh(&nf_conntrack_lock);
+ if (nf_ct_l3protos[proto->l3proto] != proto) {
+ write_unlock_bh(&nf_conntrack_lock);
+ ret = -EBUSY;
+ goto out;
+ }
+
nf_ct_l3protos[proto->l3proto] = &nf_conntrack_l3proto_generic;
write_unlock_bh(&nf_conntrack_lock);
@@ -151,6 +170,9 @@
/* Remove all contrack entries for this protocol */
nf_ct_iterate_cleanup(kill_l3proto, proto);
+
+out:
+ return ret;
}
/* FIXME: Allow NULL functions and sub in pointers to generic for
@@ -159,6 +181,11 @@
{
int ret = 0;
+ if (l4proto->l3proto >= PF_MAX) {
+ ret = -EBUSY;
+ goto out;
+ }
+
retry:
write_lock_bh(&nf_conntrack_lock);
if (nf_ct_protos[l4proto->l3proto]) {
@@ -210,9 +237,22 @@
return ret;
}
-void nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *l4proto)
+int nf_conntrack_l4proto_unregister(struct nf_conntrack_l4proto *l4proto)
{
+ int ret = 0;
+
+ if (l4proto->l3proto >= PF_MAX) {
+ ret = -EBUSY;
+ goto out;
+ }
+
write_lock_bh(&nf_conntrack_lock);
+ if (nf_ct_protos[l4proto->l3proto][l4proto->l4proto]
+ != l4proto) {
+ write_unlock_bh(&nf_conntrack_lock);
+ ret = -EBUSY;
+ goto out;
+ }
nf_ct_protos[l4proto->l3proto][l4proto->l4proto]
= &nf_conntrack_l4proto_generic;
write_unlock_bh(&nf_conntrack_lock);
@@ -222,4 +262,7 @@
/* Remove all contrack entries for this protocol */
nf_ct_iterate_cleanup(kill_l4proto, l4proto);
+
+out:
+ return ret;
}