Commit 5faa5df1 authored by Steffen Klassert's avatar Steffen Klassert Committed by David S. Miller
Browse files

inetpeer: Invalidate the inetpeer tree along with the routing cache 



We initialize the routing metrics with the values cached on the
inetpeer in rt_init_metrics(). So if we have the metrics cached on the
inetpeer, we ignore the user configured fib_metrics.

To fix this issue, we replace the old tree with a fresh initialized
inet_peer_base. The old tree is removed later with a delayed work queue.

Signed-off-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent dcf353b1

include/net/inetpeer.h

+3 −0
Original line number Diff line number Diff line
@@ -41,6 +41,7 @@ struct inet_peer { 
	u32			pmtu_orig;

	u32			pmtu_learned;

	struct inetpeer_addr_base redirect_learned;

	struct list_head	gc_list;

	/*

	 * Once inet_peer is queued for deletion (refcnt == -1), following fields

	 * are not available: rid, ip_id_count, tcp_ts, tcp_ts_stamp
@@ -96,6 +97,8 @@ static inline struct inet_peer *inet_getpeer_v6(const struct in6_addr *v6daddr, 
extern void inet_putpeer(struct inet_peer *p);

extern bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);



extern void inetpeer_invalidate_tree(int family);



/*

 * temporary check to make sure we dont access rid, ip_id_count, tcp_ts,

 * tcp_ts_stamp if no refcount is taken on inet_peer

net/ipv4/inetpeer.c

+79 −1
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ 
#include <linux/kernel.h>

#include <linux/mm.h>

#include <linux/net.h>

#include <linux/workqueue.h>

#include <net/ip.h>

#include <net/inetpeer.h>

#include <net/secure_seq.h>
@@ -66,6 +67,11 @@ 


static struct kmem_cache *peer_cachep __read_mostly;



static LIST_HEAD(gc_list);

static const int gc_delay = 60 * HZ;

static struct delayed_work gc_work;

static DEFINE_SPINLOCK(gc_lock);



#define node_height(x) x->avl_height



#define peer_avl_empty ((struct inet_peer *)&peer_fake_node)
@@ -102,6 +108,50 @@ int inet_peer_threshold __read_mostly = 65536 + 128; /* start to throw entries m 
int inet_peer_minttl __read_mostly = 120 * HZ;	/* TTL under high load: 120 sec */

int inet_peer_maxttl __read_mostly = 10 * 60 * HZ;	/* usual time to live: 10 min */



static void inetpeer_gc_worker(struct work_struct *work)

{

	struct inet_peer *p, *n;

	LIST_HEAD(list);



	spin_lock_bh(&gc_lock);

	list_replace_init(&gc_list, &list);

	spin_unlock_bh(&gc_lock);



	if (list_empty(&list))

		return;



	list_for_each_entry_safe(p, n, &list, gc_list) {



		if(need_resched())

			cond_resched();



		if (p->avl_left != peer_avl_empty) {

			list_add_tail(&p->avl_left->gc_list, &list);

			p->avl_left = peer_avl_empty;

		}



		if (p->avl_right != peer_avl_empty) {

			list_add_tail(&p->avl_right->gc_list, &list);

			p->avl_right = peer_avl_empty;

		}



		n = list_entry(p->gc_list.next, struct inet_peer, gc_list);



		if (!atomic_read(&p->refcnt)) {

			list_del(&p->gc_list);

			kmem_cache_free(peer_cachep, p);

		}

	}



	if (list_empty(&list))

		return;



	spin_lock_bh(&gc_lock);

	list_splice(&list, &gc_list);

	spin_unlock_bh(&gc_lock);



	schedule_delayed_work(&gc_work, gc_delay);

}



/* Called from ip_output.c:ip_init  */

void __init inet_initpeers(void)
@@ -126,6 +176,7 @@ void __init inet_initpeers(void) 
			0, SLAB_HWCACHE_ALIGN | SLAB_PANIC,

			NULL);



	INIT_DELAYED_WORK_DEFERRABLE(&gc_work, inetpeer_gc_worker);

}



static int addr_compare(const struct inetpeer_addr *a,
@@ -449,7 +500,7 @@ relookup: 
		p->pmtu_orig = 0;

		p->redirect_genid = 0;

		memset(&p->redirect_learned, 0, sizeof(p->redirect_learned));



		INIT_LIST_HEAD(&p->gc_list);



		/* Link the node. */

		link_to_pool(p, base);
@@ -509,3 +560,30 @@ bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout) 
	return rc;

}

EXPORT_SYMBOL(inet_peer_xrlim_allow);



void inetpeer_invalidate_tree(int family)

{

	struct inet_peer *old, *new, *prev;

	struct inet_peer_base *base = family_to_base(family);



	write_seqlock_bh(&base->lock);



	old = base->root;

	if (old == peer_avl_empty_rcu)

		goto out;



	new = peer_avl_empty_rcu;



	prev = cmpxchg(&base->root, old, new);

	if (prev == old) {

		base->total = 0;

		spin_lock(&gc_lock);

		list_add_tail(&prev->gc_list, &gc_list);

		spin_unlock(&gc_lock);

		schedule_delayed_work(&gc_work, gc_delay);

	}



out:

	write_sequnlock_bh(&base->lock);

}

EXPORT_SYMBOL(inetpeer_invalidate_tree);

net/ipv4/route.c

+1 −0
Original line number Diff line number Diff line
@@ -938,6 +938,7 @@ static void rt_cache_invalidate(struct net *net) 
	get_random_bytes(&shuffle, sizeof(shuffle));

	atomic_add(shuffle + 1U, &net->ipv4.rt_genid);

	redirect_genid++;

	inetpeer_invalidate_tree(AF_INET);

}



/*

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