From e7d8f6cb2f8735693396872f4608bbe305e8baee Mon Sep 17 00:00:00 2001 From: Steffen Klassert Date: Tue, 8 Oct 2013 10:49:45 +0200 Subject: [PATCH] xfrm: Add refcount handling to queued policies We need to ensure that policies can't go away as long as the hold timer is armed, so take a refcont when we arm the timer and drop one if we delete it. Bug was introduced with git commit a0073fe18 ("xfrm: Add a state resolution packet queue") Signed-off-by: Steffen Klassert --- net/xfrm/xfrm_policy.c | 24 +++++++++++++++++------- 1 file changed, 17 insertions(+), 7 deletions(-) diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index ed38d5d81f9e..5f9be976770e 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -334,7 +334,8 @@ static void xfrm_policy_kill(struct xfrm_policy *policy) atomic_inc(&policy->genid); - del_timer(&policy->polq.hold_timer); + if (del_timer(&policy->polq.hold_timer)) + xfrm_pol_put(policy); xfrm_queue_purge(&policy->polq.hold_queue); if (del_timer(&policy->timer)) @@ -589,7 +590,8 @@ static void xfrm_policy_requeue(struct xfrm_policy *old, spin_lock_bh(&pq->hold_queue.lock); skb_queue_splice_init(&pq->hold_queue, &list); - del_timer(&pq->hold_timer); + if (del_timer(&pq->hold_timer)) + xfrm_pol_put(old); spin_unlock_bh(&pq->hold_queue.lock); if (skb_queue_empty(&list)) @@ -600,7 +602,8 @@ static void xfrm_policy_requeue(struct xfrm_policy *old, spin_lock_bh(&pq->hold_queue.lock); skb_queue_splice(&list, &pq->hold_queue); pq->timeout = XFRM_QUEUE_TMO_MIN; - mod_timer(&pq->hold_timer, jiffies); + if (!mod_timer(&pq->hold_timer, jiffies)) + xfrm_pol_hold(new); spin_unlock_bh(&pq->hold_queue.lock); } @@ -1787,8 +1790,9 @@ static void xfrm_policy_queue_process(unsigned long arg) goto purge_queue; pq->timeout = pq->timeout << 1; - mod_timer(&pq->hold_timer, jiffies + pq->timeout); - return; + if (!mod_timer(&pq->hold_timer, jiffies + pq->timeout)) + xfrm_pol_hold(pol); + goto out; } dst_release(dst); @@ -1819,11 +1823,14 @@ static void xfrm_policy_queue_process(unsigned long arg) err = dst_output(skb); } +out: + xfrm_pol_put(pol); return; purge_queue: pq->timeout = 0; xfrm_queue_purge(&pq->hold_queue); + xfrm_pol_put(pol); } static int xdst_queue_output(struct sk_buff *skb) @@ -1831,7 +1838,8 @@ static int xdst_queue_output(struct sk_buff *skb) unsigned long sched_next; struct dst_entry *dst = skb_dst(skb); struct xfrm_dst *xdst = (struct xfrm_dst *) dst; - struct xfrm_policy_queue *pq = &xdst->pols[0]->polq; + struct xfrm_policy *pol = xdst->pols[0]; + struct xfrm_policy_queue *pq = &pol->polq; if (pq->hold_queue.qlen > XFRM_MAX_QUEUE_LEN) { kfree_skb(skb); @@ -1850,10 +1858,12 @@ static int xdst_queue_output(struct sk_buff *skb) if (del_timer(&pq->hold_timer)) { if (time_before(pq->hold_timer.expires, sched_next)) sched_next = pq->hold_timer.expires; + xfrm_pol_put(pol); } __skb_queue_tail(&pq->hold_queue, skb); - mod_timer(&pq->hold_timer, sched_next); + if (!mod_timer(&pq->hold_timer, sched_next)) + xfrm_pol_hold(pol); spin_unlock_bh(&pq->hold_queue.lock); -- 2.34.1