kernel_optimize_test/security/selinux/include/xfrm.h
Kirill Tkhai f0b07bb151 net: Introduce net_rwsem to protect net_namespace_list
rtnl_lock() is used everywhere, and contention is very high.
When someone wants to iterate over alive net namespaces,
he/she has no a possibility to do that without exclusive lock.
But the exclusive rtnl_lock() in such places is overkill,
and it just increases the contention. Yes, there is already
for_each_net_rcu() in kernel, but it requires rcu_read_lock(),
and this can't be sleepable. Also, sometimes it may be need
really prevent net_namespace_list growth, so for_each_net_rcu()
is not fit there.

This patch introduces new rw_semaphore, which will be used
instead of rtnl_mutex to protect net_namespace_list. It is
sleepable and allows not-exclusive iterations over net
namespaces list. It allows to stop using rtnl_lock()
in several places (what is made in next patches) and makes
less the time, we keep rtnl_mutex. Here we just add new lock,
while the explanation of we can remove rtnl_lock() there are
in next patches.

Fine grained locks generally are better, then one big lock,
so let's do that with net_namespace_list, while the situation
allows that.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-29 13:47:53 -04:00

95 lines
2.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* SELinux support for the XFRM LSM hooks
*
* Author : Trent Jaeger, <jaegert@us.ibm.com>
* Updated : Venkat Yekkirala, <vyekkirala@TrustedCS.com>
*/
#ifndef _SELINUX_XFRM_H_
#define _SELINUX_XFRM_H_
#include <net/flow.h>
int selinux_xfrm_policy_alloc(struct xfrm_sec_ctx **ctxp,
struct xfrm_user_sec_ctx *uctx,
gfp_t gfp);
int selinux_xfrm_policy_clone(struct xfrm_sec_ctx *old_ctx,
struct xfrm_sec_ctx **new_ctxp);
void selinux_xfrm_policy_free(struct xfrm_sec_ctx *ctx);
int selinux_xfrm_policy_delete(struct xfrm_sec_ctx *ctx);
int selinux_xfrm_state_alloc(struct xfrm_state *x,
struct xfrm_user_sec_ctx *uctx);
int selinux_xfrm_state_alloc_acquire(struct xfrm_state *x,
struct xfrm_sec_ctx *polsec, u32 secid);
void selinux_xfrm_state_free(struct xfrm_state *x);
int selinux_xfrm_state_delete(struct xfrm_state *x);
int selinux_xfrm_policy_lookup(struct xfrm_sec_ctx *ctx, u32 fl_secid, u8 dir);
int selinux_xfrm_state_pol_flow_match(struct xfrm_state *x,
struct xfrm_policy *xp,
const struct flowi *fl);
#ifdef CONFIG_SECURITY_NETWORK_XFRM
extern atomic_t selinux_xfrm_refcount;
static inline int selinux_xfrm_enabled(void)
{
return (atomic_read(&selinux_xfrm_refcount) > 0);
}
int selinux_xfrm_sock_rcv_skb(u32 sk_sid, struct sk_buff *skb,
struct common_audit_data *ad);
int selinux_xfrm_postroute_last(u32 sk_sid, struct sk_buff *skb,
struct common_audit_data *ad, u8 proto);
int selinux_xfrm_decode_session(struct sk_buff *skb, u32 *sid, int ckall);
int selinux_xfrm_skb_sid(struct sk_buff *skb, u32 *sid);
static inline void selinux_xfrm_notify_policyload(void)
{
struct net *net;
rtnl_lock();
down_read(&net_rwsem);
for_each_net(net)
rt_genid_bump_all(net);
up_read(&net_rwsem);
rtnl_unlock();
}
#else
static inline int selinux_xfrm_enabled(void)
{
return 0;
}
static inline int selinux_xfrm_sock_rcv_skb(u32 sk_sid, struct sk_buff *skb,
struct common_audit_data *ad)
{
return 0;
}
static inline int selinux_xfrm_postroute_last(u32 sk_sid, struct sk_buff *skb,
struct common_audit_data *ad,
u8 proto)
{
return 0;
}
static inline int selinux_xfrm_decode_session(struct sk_buff *skb, u32 *sid,
int ckall)
{
*sid = SECSID_NULL;
return 0;
}
static inline void selinux_xfrm_notify_policyload(void)
{
}
static inline int selinux_xfrm_skb_sid(struct sk_buff *skb, u32 *sid)
{
*sid = SECSID_NULL;
return 0;
}
#endif
#endif /* _SELINUX_XFRM_H_ */