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netns xfrm: xfrm6_tunnel in netns
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I'm not sure about rcu stuff near kmem cache destruction:
* checks for non-empty hashes look bogus, they're done _before_
  rcu_berrier()
* unregistering netns ops is done before kmem_cache destoy
  (as it should), and unregistering involves rcu barriers by itself

So it looks nothing should be done.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Alexey Dobriyan authored and David S. Miller committed Jan 28, 2010
1 parent e924960 commit a166477
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Showing 3 changed files with 88 additions and 62 deletions.
6 changes: 3 additions & 3 deletions include/net/xfrm.h
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Original file line number Diff line number Diff line change
Expand Up @@ -1408,9 +1408,9 @@ extern int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
xfrm_address_t *saddr, u8 proto);
extern int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family);
extern int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler, unsigned short family);
extern __be32 xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr);
extern void xfrm6_tunnel_free_spi(xfrm_address_t *saddr);
extern __be32 xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr);
extern __be32 xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr);
extern void xfrm6_tunnel_free_spi(struct net *net, xfrm_address_t *saddr);
extern __be32 xfrm6_tunnel_spi_lookup(struct net *net, xfrm_address_t *saddr);
extern int xfrm6_extract_output(struct xfrm_state *x, struct sk_buff *skb);
extern int xfrm6_prepare_output(struct xfrm_state *x, struct sk_buff *skb);
extern int xfrm6_output(struct sk_buff *skb);
Expand Down
4 changes: 2 additions & 2 deletions net/ipv6/ipcomp6.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -81,7 +81,7 @@ static struct xfrm_state *ipcomp6_tunnel_create(struct xfrm_state *x)
goto out;

t->id.proto = IPPROTO_IPV6;
t->id.spi = xfrm6_tunnel_alloc_spi((xfrm_address_t *)&x->props.saddr);
t->id.spi = xfrm6_tunnel_alloc_spi(&init_net, (xfrm_address_t *)&x->props.saddr);
if (!t->id.spi)
goto error;

Expand Down Expand Up @@ -112,7 +112,7 @@ static int ipcomp6_tunnel_attach(struct xfrm_state *x)
struct xfrm_state *t = NULL;
__be32 spi;

spi = xfrm6_tunnel_spi_lookup((xfrm_address_t *)&x->props.saddr);
spi = xfrm6_tunnel_spi_lookup(&init_net, (xfrm_address_t *)&x->props.saddr);
if (spi)
t = xfrm_state_lookup(&init_net, (xfrm_address_t *)&x->id.daddr,
spi, IPPROTO_IPV6, AF_INET6);
Expand Down
140 changes: 83 additions & 57 deletions net/ipv6/xfrm6_tunnel.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -30,6 +30,25 @@
#include <linux/ipv6.h>
#include <linux/icmpv6.h>
#include <linux/mutex.h>
#include <net/netns/generic.h>

#define XFRM6_TUNNEL_SPI_BYADDR_HSIZE 256
#define XFRM6_TUNNEL_SPI_BYSPI_HSIZE 256

#define XFRM6_TUNNEL_SPI_MIN 1
#define XFRM6_TUNNEL_SPI_MAX 0xffffffff

struct xfrm6_tunnel_net {
struct hlist_head spi_byaddr[XFRM6_TUNNEL_SPI_BYADDR_HSIZE];
struct hlist_head spi_byspi[XFRM6_TUNNEL_SPI_BYSPI_HSIZE];
u32 spi;
};

static int xfrm6_tunnel_net_id __read_mostly;
static inline struct xfrm6_tunnel_net *xfrm6_tunnel_pernet(struct net *net)
{
return net_generic(net, xfrm6_tunnel_net_id);
}

/*
* xfrm_tunnel_spi things are for allocating unique id ("spi")
Expand All @@ -46,19 +65,8 @@ struct xfrm6_tunnel_spi {

static DEFINE_SPINLOCK(xfrm6_tunnel_spi_lock);

static u32 xfrm6_tunnel_spi;

#define XFRM6_TUNNEL_SPI_MIN 1
#define XFRM6_TUNNEL_SPI_MAX 0xffffffff

static struct kmem_cache *xfrm6_tunnel_spi_kmem __read_mostly;

#define XFRM6_TUNNEL_SPI_BYADDR_HSIZE 256
#define XFRM6_TUNNEL_SPI_BYSPI_HSIZE 256

static struct hlist_head xfrm6_tunnel_spi_byaddr[XFRM6_TUNNEL_SPI_BYADDR_HSIZE];
static struct hlist_head xfrm6_tunnel_spi_byspi[XFRM6_TUNNEL_SPI_BYSPI_HSIZE];

static inline unsigned xfrm6_tunnel_spi_hash_byaddr(xfrm_address_t *addr)
{
unsigned h;
Expand All @@ -77,49 +85,30 @@ static inline unsigned xfrm6_tunnel_spi_hash_byspi(u32 spi)
}


static int xfrm6_tunnel_spi_init(void)
static int __init xfrm6_tunnel_spi_init(void)
{
int i;

xfrm6_tunnel_spi = 0;
xfrm6_tunnel_spi_kmem = kmem_cache_create("xfrm6_tunnel_spi",
sizeof(struct xfrm6_tunnel_spi),
0, SLAB_HWCACHE_ALIGN,
NULL);
if (!xfrm6_tunnel_spi_kmem)
return -ENOMEM;

for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
INIT_HLIST_HEAD(&xfrm6_tunnel_spi_byaddr[i]);
for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
INIT_HLIST_HEAD(&xfrm6_tunnel_spi_byspi[i]);
return 0;
}

static void xfrm6_tunnel_spi_fini(void)
{
int i;

for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++) {
if (!hlist_empty(&xfrm6_tunnel_spi_byaddr[i]))
return;
}
for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++) {
if (!hlist_empty(&xfrm6_tunnel_spi_byspi[i]))
return;
}
rcu_barrier();
kmem_cache_destroy(xfrm6_tunnel_spi_kmem);
xfrm6_tunnel_spi_kmem = NULL;
}

static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr)
static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(struct net *net, xfrm_address_t *saddr)
{
struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
struct xfrm6_tunnel_spi *x6spi;
struct hlist_node *pos;

hlist_for_each_entry_rcu(x6spi, pos,
&xfrm6_tunnel_spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
&xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
list_byaddr) {
if (memcmp(&x6spi->addr, saddr, sizeof(x6spi->addr)) == 0)
return x6spi;
Expand All @@ -128,61 +117,63 @@ static struct xfrm6_tunnel_spi *__xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr)
return NULL;
}

__be32 xfrm6_tunnel_spi_lookup(xfrm_address_t *saddr)
__be32 xfrm6_tunnel_spi_lookup(struct net *net, xfrm_address_t *saddr)
{
struct xfrm6_tunnel_spi *x6spi;
u32 spi;

rcu_read_lock_bh();
x6spi = __xfrm6_tunnel_spi_lookup(saddr);
x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
spi = x6spi ? x6spi->spi : 0;
rcu_read_unlock_bh();
return htonl(spi);
}

EXPORT_SYMBOL(xfrm6_tunnel_spi_lookup);

static int __xfrm6_tunnel_spi_check(u32 spi)
static int __xfrm6_tunnel_spi_check(struct net *net, u32 spi)
{
struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
struct xfrm6_tunnel_spi *x6spi;
int index = xfrm6_tunnel_spi_hash_byspi(spi);
struct hlist_node *pos;

hlist_for_each_entry(x6spi, pos,
&xfrm6_tunnel_spi_byspi[index],
&xfrm6_tn->spi_byspi[index],
list_byspi) {
if (x6spi->spi == spi)
return -1;
}
return index;
}

static u32 __xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr)
static u32 __xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
{
struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
u32 spi;
struct xfrm6_tunnel_spi *x6spi;
int index;

if (xfrm6_tunnel_spi < XFRM6_TUNNEL_SPI_MIN ||
xfrm6_tunnel_spi >= XFRM6_TUNNEL_SPI_MAX)
xfrm6_tunnel_spi = XFRM6_TUNNEL_SPI_MIN;
if (xfrm6_tn->spi < XFRM6_TUNNEL_SPI_MIN ||
xfrm6_tn->spi >= XFRM6_TUNNEL_SPI_MAX)
xfrm6_tn->spi = XFRM6_TUNNEL_SPI_MIN;
else
xfrm6_tunnel_spi++;
xfrm6_tn->spi++;

for (spi = xfrm6_tunnel_spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) {
index = __xfrm6_tunnel_spi_check(spi);
for (spi = xfrm6_tn->spi; spi <= XFRM6_TUNNEL_SPI_MAX; spi++) {
index = __xfrm6_tunnel_spi_check(net, spi);
if (index >= 0)
goto alloc_spi;
}
for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tunnel_spi; spi++) {
index = __xfrm6_tunnel_spi_check(spi);
for (spi = XFRM6_TUNNEL_SPI_MIN; spi < xfrm6_tn->spi; spi++) {
index = __xfrm6_tunnel_spi_check(net, spi);
if (index >= 0)
goto alloc_spi;
}
spi = 0;
goto out;
alloc_spi:
xfrm6_tunnel_spi = spi;
xfrm6_tn->spi = spi;
x6spi = kmem_cache_alloc(xfrm6_tunnel_spi_kmem, GFP_ATOMIC);
if (!x6spi)
goto out;
Expand All @@ -192,26 +183,26 @@ static u32 __xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr)
x6spi->spi = spi;
atomic_set(&x6spi->refcnt, 1);

hlist_add_head_rcu(&x6spi->list_byspi, &xfrm6_tunnel_spi_byspi[index]);
hlist_add_head_rcu(&x6spi->list_byspi, &xfrm6_tn->spi_byspi[index]);

index = xfrm6_tunnel_spi_hash_byaddr(saddr);
hlist_add_head_rcu(&x6spi->list_byaddr, &xfrm6_tunnel_spi_byaddr[index]);
hlist_add_head_rcu(&x6spi->list_byaddr, &xfrm6_tn->spi_byaddr[index]);
out:
return spi;
}

__be32 xfrm6_tunnel_alloc_spi(xfrm_address_t *saddr)
__be32 xfrm6_tunnel_alloc_spi(struct net *net, xfrm_address_t *saddr)
{
struct xfrm6_tunnel_spi *x6spi;
u32 spi;

spin_lock_bh(&xfrm6_tunnel_spi_lock);
x6spi = __xfrm6_tunnel_spi_lookup(saddr);
x6spi = __xfrm6_tunnel_spi_lookup(net, saddr);
if (x6spi) {
atomic_inc(&x6spi->refcnt);
spi = x6spi->spi;
} else
spi = __xfrm6_tunnel_alloc_spi(saddr);
spi = __xfrm6_tunnel_alloc_spi(net, saddr);
spin_unlock_bh(&xfrm6_tunnel_spi_lock);

return htonl(spi);
Expand All @@ -225,15 +216,16 @@ static void x6spi_destroy_rcu(struct rcu_head *head)
container_of(head, struct xfrm6_tunnel_spi, rcu_head));
}

void xfrm6_tunnel_free_spi(xfrm_address_t *saddr)
void xfrm6_tunnel_free_spi(struct net *net, xfrm_address_t *saddr)
{
struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
struct xfrm6_tunnel_spi *x6spi;
struct hlist_node *pos, *n;

spin_lock_bh(&xfrm6_tunnel_spi_lock);

hlist_for_each_entry_safe(x6spi, pos, n,
&xfrm6_tunnel_spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
&xfrm6_tn->spi_byaddr[xfrm6_tunnel_spi_hash_byaddr(saddr)],
list_byaddr)
{
if (memcmp(&x6spi->addr, saddr, sizeof(x6spi->addr)) == 0) {
Expand Down Expand Up @@ -263,10 +255,11 @@ static int xfrm6_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)

static int xfrm6_tunnel_rcv(struct sk_buff *skb)
{
struct net *net = dev_net(skb->dev);
struct ipv6hdr *iph = ipv6_hdr(skb);
__be32 spi;

spi = xfrm6_tunnel_spi_lookup((xfrm_address_t *)&iph->saddr);
spi = xfrm6_tunnel_spi_lookup(net, (xfrm_address_t *)&iph->saddr);
return xfrm6_rcv_spi(skb, IPPROTO_IPV6, spi) > 0 ? : 0;
}

Expand Down Expand Up @@ -326,7 +319,9 @@ static int xfrm6_tunnel_init_state(struct xfrm_state *x)

static void xfrm6_tunnel_destroy(struct xfrm_state *x)
{
xfrm6_tunnel_free_spi((xfrm_address_t *)&x->props.saddr);
struct net *net = xs_net(x);

xfrm6_tunnel_free_spi(net, (xfrm_address_t *)&x->props.saddr);
}

static const struct xfrm_type xfrm6_tunnel_type = {
Expand All @@ -351,6 +346,31 @@ static struct xfrm6_tunnel xfrm46_tunnel_handler = {
.priority = 2,
};

static int __net_init xfrm6_tunnel_net_init(struct net *net)
{
struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net);
unsigned int i;

for (i = 0; i < XFRM6_TUNNEL_SPI_BYADDR_HSIZE; i++)
INIT_HLIST_HEAD(&xfrm6_tn->spi_byaddr[i]);
for (i = 0; i < XFRM6_TUNNEL_SPI_BYSPI_HSIZE; i++)
INIT_HLIST_HEAD(&xfrm6_tn->spi_byspi[i]);
xfrm6_tn->spi = 0;

return 0;
}

static void __net_exit xfrm6_tunnel_net_exit(struct net *net)
{
}

static struct pernet_operations xfrm6_tunnel_net_ops = {
.init = xfrm6_tunnel_net_init,
.exit = xfrm6_tunnel_net_exit,
.id = &xfrm6_tunnel_net_id,
.size = sizeof(struct xfrm6_tunnel_net),
};

static int __init xfrm6_tunnel_init(void)
{
int rv;
Expand All @@ -367,8 +387,13 @@ static int __init xfrm6_tunnel_init(void)
rv = xfrm6_tunnel_spi_init();
if (rv < 0)
goto dereg46;
rv = register_pernet_subsys(&xfrm6_tunnel_net_ops);
if (rv < 0)
goto deregspi;
return 0;

deregspi:
xfrm6_tunnel_spi_fini();
dereg46:
xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET);
dereg6:
Expand All @@ -381,6 +406,7 @@ static int __init xfrm6_tunnel_init(void)

static void __exit xfrm6_tunnel_fini(void)
{
unregister_pernet_subsys(&xfrm6_tunnel_net_ops);
xfrm6_tunnel_spi_fini();
xfrm6_tunnel_deregister(&xfrm46_tunnel_handler, AF_INET);
xfrm6_tunnel_deregister(&xfrm6_tunnel_handler, AF_INET6);
Expand Down

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