linux/include/net/inetpeer.h
Reshetova, Elena 1cc9a98b59 net: convert inet_peer.refcnt from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
This conversion requires overall +1 on the whole
refcounting scheme.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-01 07:39:07 -07:00

158 lines
3.4 KiB
C

/*
* INETPEER - A storage for permanent information about peers
*
* Authors: Andrey V. Savochkin <saw@msu.ru>
*/
#ifndef _NET_INETPEER_H
#define _NET_INETPEER_H
#include <linux/types.h>
#include <linux/init.h>
#include <linux/jiffies.h>
#include <linux/spinlock.h>
#include <linux/rtnetlink.h>
#include <net/ipv6.h>
#include <linux/atomic.h>
/* IPv4 address key for cache lookups */
struct ipv4_addr_key {
__be32 addr;
int vif;
};
#define INETPEER_MAXKEYSZ (sizeof(struct in6_addr) / sizeof(u32))
struct inetpeer_addr {
union {
struct ipv4_addr_key a4;
struct in6_addr a6;
u32 key[INETPEER_MAXKEYSZ];
};
__u16 family;
};
struct inet_peer {
/* group together avl_left,avl_right,v4daddr to speedup lookups */
struct inet_peer __rcu *avl_left, *avl_right;
struct inetpeer_addr daddr;
__u32 avl_height;
u32 metrics[RTAX_MAX];
u32 rate_tokens; /* rate limiting for ICMP */
unsigned long rate_last;
union {
struct list_head gc_list;
struct rcu_head gc_rcu;
};
/*
* Once inet_peer is queued for deletion (refcnt == 0), following field
* is not available: rid
* We can share memory with rcu_head to help keep inet_peer small.
*/
union {
struct {
atomic_t rid; /* Frag reception counter */
};
struct rcu_head rcu;
struct inet_peer *gc_next;
};
/* following fields might be frequently dirtied */
__u32 dtime; /* the time of last use of not referenced entries */
refcount_t refcnt;
};
struct inet_peer_base {
struct inet_peer __rcu *root;
seqlock_t lock;
int total;
};
void inet_peer_base_init(struct inet_peer_base *);
void inet_initpeers(void) __init;
#define INETPEER_METRICS_NEW (~(u32) 0)
static inline void inetpeer_set_addr_v4(struct inetpeer_addr *iaddr, __be32 ip)
{
iaddr->a4.addr = ip;
iaddr->a4.vif = 0;
iaddr->family = AF_INET;
}
static inline __be32 inetpeer_get_addr_v4(struct inetpeer_addr *iaddr)
{
return iaddr->a4.addr;
}
static inline void inetpeer_set_addr_v6(struct inetpeer_addr *iaddr,
struct in6_addr *in6)
{
iaddr->a6 = *in6;
iaddr->family = AF_INET6;
}
static inline struct in6_addr *inetpeer_get_addr_v6(struct inetpeer_addr *iaddr)
{
return &iaddr->a6;
}
/* can be called with or without local BH being disabled */
struct inet_peer *inet_getpeer(struct inet_peer_base *base,
const struct inetpeer_addr *daddr,
int create);
static inline struct inet_peer *inet_getpeer_v4(struct inet_peer_base *base,
__be32 v4daddr,
int vif, int create)
{
struct inetpeer_addr daddr;
daddr.a4.addr = v4daddr;
daddr.a4.vif = vif;
daddr.family = AF_INET;
return inet_getpeer(base, &daddr, create);
}
static inline struct inet_peer *inet_getpeer_v6(struct inet_peer_base *base,
const struct in6_addr *v6daddr,
int create)
{
struct inetpeer_addr daddr;
daddr.a6 = *v6daddr;
daddr.family = AF_INET6;
return inet_getpeer(base, &daddr, create);
}
static inline int inetpeer_addr_cmp(const struct inetpeer_addr *a,
const struct inetpeer_addr *b)
{
int i, n;
if (a->family == AF_INET)
n = sizeof(a->a4) / sizeof(u32);
else
n = sizeof(a->a6) / sizeof(u32);
for (i = 0; i < n; i++) {
if (a->key[i] == b->key[i])
continue;
if (a->key[i] < b->key[i])
return -1;
return 1;
}
return 0;
}
/* can be called from BH context or outside */
void inet_putpeer(struct inet_peer *p);
bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout);
void inetpeer_invalidate_tree(struct inet_peer_base *);
#endif /* _NET_INETPEER_H */