xfrm: force a garbage collection after deleting a policy

In some cases after deleting a policy from the SPD the policy would
remain in the dst/flow/route cache for an extended period of time
which caused problems for SELinux as its dynamic network access
controls key off of the number of XFRM policy and state entries.
This patch corrects this problem by forcing a XFRM garbage collection
whenever a policy is sucessfully removed.

Reported-by: Ondrej Moris <omoris@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 13 insertions, 1 deletions

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index ae16531d0d35..94ce082b29dc 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -1160,6 +1160,8 @@ static inline void xfrm_sk_free_policy(struct sock *sk)
         }
 }
 
+extern void xfrm_garbage_collect(struct net *net);
+
 #else
 
 static inline void xfrm_sk_free_policy(struct sock *sk) {}
@@ -1194,6 +1196,9 @@ static inline int xfrm6_policy_check_reverse(struct sock *sk, int dir,
 {
         return 1;
 }
+static inline void xfrm_garbage_collect(struct net *net)
+{
+}
 #endif
 
 static __inline__
diff --git a/net/key/af_key.c b/net/key/af_key.c
index 5b1e5af25713..c5fbd7589681 100644
--- a/net/key/af_key.c
+++ b/net/key/af_key.c
@@ -2366,6 +2366,8 @@ static int pfkey_spddelete(struct sock *sk, struct sk_buff *skb, const struct sa
 
 out:
         xfrm_pol_put(xp);
+        if (err == 0)
+                xfrm_garbage_collect(net);
         return err;
 }
 
@@ -2615,6 +2617,8 @@ static int pfkey_spdget(struct sock *sk, struct sk_buff *skb, const struct sadb_
 
 out:
         xfrm_pol_put(xp);
+        if (delete && err == 0)
+                xfrm_garbage_collect(net);
         return err;
 }
 
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 23cea0f74336..ea970b8002a2 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2557,11 +2557,12 @@ static void __xfrm_garbage_collect(struct net *net)
         }
 }
 
-static void xfrm_garbage_collect(struct net *net)
+void xfrm_garbage_collect(struct net *net)
 {
         flow_cache_flush();
         __xfrm_garbage_collect(net);
 }
+EXPORT_SYMBOL(xfrm_garbage_collect);
 
 static void xfrm_garbage_collect_deferred(struct net *net)
 {
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index aa778748c565..3f565e495ac6 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1681,6 +1681,8 @@ static int xfrm_get_policy(struct sk_buff *skb, struct nlmsghdr *nlh,
 
 out:
         xfrm_pol_put(xp);
+        if (delete && err == 0)
+                xfrm_garbage_collect(net);
         return err;
 }