[PATCH 4.19 34/46] xfrm_user: fix freeing of xfrm states on acquire

[Greg Kroah-Hartman]

4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Mathias Krause <mini...@googlemail.com>

commit 4a135e538962cb00a9667c82e7d2b9e4d7cd7177 upstream.

Commit 565f0fa902b6 ("xfrm: use a dedicated slab cache for struct
xfrm_state") moved xfrm state objects to use their own slab cache.
However, it missed to adapt xfrm_user to use this new cache when
freeing xfrm states.

Fix this by introducing and make use of a new helper for freeing
xfrm_state objects.

Fixes: 565f0fa902b6 ("xfrm: use a dedicated slab cache for struct xfrm_state")
Reported-by: Pan Bian <bianpan2...@163.com>
Cc: <sta...@vger.kernel.org> # v4.18+
Signed-off-by: Mathias Krause <mini...@googlemail.com>
Acked-by: Herbert Xu <herb...@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klass...@secunet.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 include/net/xfrm.h    |    1 +
 net/xfrm/xfrm_state.c |    8 +++++++-
 net/xfrm/xfrm_user.c  |    4 ++--
 3 files changed, 10 insertions(+), 3 deletions(-)

--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -1552,6 +1552,7 @@ int xfrm_state_walk(struct net *net, str
                    int (*func)(struct xfrm_state *, int, void*), void *);
 void xfrm_state_walk_done(struct xfrm_state_walk *walk, struct net *net);
 struct xfrm_state *xfrm_state_alloc(struct net *net);
+void xfrm_state_free(struct xfrm_state *x);
 struct xfrm_state *xfrm_state_find(const xfrm_address_t *daddr,
                                   const xfrm_address_t *saddr,
                                   const struct flowi *fl,
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -426,6 +426,12 @@ static void xfrm_put_mode(struct xfrm_mo
        module_put(mode->owner);
 }
 
+void xfrm_state_free(struct xfrm_state *x)
+{
+       kmem_cache_free(xfrm_state_cache, x);
+}
+EXPORT_SYMBOL(xfrm_state_free);
+
 static void xfrm_state_gc_destroy(struct xfrm_state *x)
 {
        tasklet_hrtimer_cancel(&x->mtimer);
@@ -452,7 +458,7 @@ static void xfrm_state_gc_destroy(struct
        }
        xfrm_dev_state_free(x);
        security_xfrm_state_free(x);
-       kmem_cache_free(xfrm_state_cache, x);
+       xfrm_state_free(x);
 }
 
 static void xfrm_state_gc_task(struct work_struct *work)
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -2288,13 +2288,13 @@ static int xfrm_add_acquire(struct sk_bu
 
        }
 
-       kfree(x);
+       xfrm_state_free(x);
        kfree(xp);
 
        return 0;
 
 free_state:
-       kfree(x);
+       xfrm_state_free(x);
 nomem:
        return err;
 }