net: check for refcount if pop a stacked dst_entry

xfrm triggers a warning if dst_pop() drops a refcount
on a noref dst. This patch changes dst_pop() to
skb_dst_pop(). skb_dst_pop() drops the refcnt only
on a refcounted dst. Also we don't clone the child
dst_entry, so it is not refcounted and we can use
skb_dst_set_noref() in xfrm_output_one().

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Steffen Klassert 2010-06-04 01:57:38 +00:00 committed by David S. Miller
parent 4f4aeb7fd0
commit 8764ab2ca7
2 changed files with 5 additions and 5 deletions

View file

@ -250,11 +250,11 @@ static inline void skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev)
* Linux networking. Thus, destinations are stackable.
*/
static inline struct dst_entry *dst_pop(struct dst_entry *dst)
static inline struct dst_entry *skb_dst_pop(struct sk_buff *skb)
{
struct dst_entry *child = dst_clone(dst->child);
struct dst_entry *child = skb_dst(skb)->child;
dst_release(dst);
skb_dst_drop(skb);
return child;
}

View file

@ -95,13 +95,13 @@ static int xfrm_output_one(struct sk_buff *skb, int err)
goto error_nolock;
}
dst = dst_pop(dst);
dst = skb_dst_pop(skb);
if (!dst) {
XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
err = -EHOSTUNREACH;
goto error_nolock;
}
skb_dst_set(skb, dst);
skb_dst_set_noref(skb, dst);
x = dst->xfrm;
} while (x && !(x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL));