[GFS2] Add nanosecond timestamp feature
[safe/jmp/linux-2.6] / net / xfrm / xfrm_state.c
index 899de9e..dfacb9c 100644 (file)
 #include <linux/module.h>
 #include <linux/cache.h>
 #include <asm/uaccess.h>
+#include <linux/audit.h>
+#include <linux/cache.h>
 
 #include "xfrm_hash.h"
 
 struct sock *xfrm_nl;
 EXPORT_SYMBOL(xfrm_nl);
 
-u32 sysctl_xfrm_aevent_etime = XFRM_AE_ETIME;
+u32 sysctl_xfrm_aevent_etime __read_mostly = XFRM_AE_ETIME;
 EXPORT_SYMBOL(sysctl_xfrm_aevent_etime);
 
-u32 sysctl_xfrm_aevent_rseqth = XFRM_AE_SEQT_SIZE;
+u32 sysctl_xfrm_aevent_rseqth __read_mostly = XFRM_AE_SEQT_SIZE;
 EXPORT_SYMBOL(sysctl_xfrm_aevent_rseqth);
 
+u32 sysctl_xfrm_acq_expires __read_mostly = 30;
+
 /* Each xfrm_state may be linked to two tables:
 
    1. Hash table by (spi,daddr,ah/esp) to find SA by SPI. (input,ctl)
@@ -115,7 +119,7 @@ static unsigned long xfrm_hash_new_size(void)
 
 static DEFINE_MUTEX(hash_resize_mutex);
 
-static void xfrm_hash_resize(void *__unused)
+static void xfrm_hash_resize(struct work_struct *__unused)
 {
        struct hlist_head *ndst, *nsrc, *nspi, *odst, *osrc, *ospi;
        unsigned long nsize, osize;
@@ -168,7 +172,7 @@ out_unlock:
        mutex_unlock(&hash_resize_mutex);
 }
 
-static DECLARE_WORK(xfrm_hash_work, xfrm_hash_resize, NULL);
+static DECLARE_WORK(xfrm_hash_work, xfrm_hash_resize);
 
 DECLARE_WAIT_QUEUE_HEAD(km_waitq);
 EXPORT_SYMBOL(km_waitq);
@@ -182,9 +186,6 @@ static DEFINE_SPINLOCK(xfrm_state_gc_lock);
 
 int __xfrm_state_delete(struct xfrm_state *x);
 
-static struct xfrm_state_afinfo *xfrm_state_get_afinfo(unsigned short family);
-static void xfrm_state_put_afinfo(struct xfrm_state_afinfo *afinfo);
-
 int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol);
 void km_state_expired(struct xfrm_state *x, int hard, u32 pid);
 
@@ -207,7 +208,7 @@ static void xfrm_state_gc_destroy(struct xfrm_state *x)
        kfree(x);
 }
 
-static void xfrm_state_gc_task(void *data)
+static void xfrm_state_gc_task(struct work_struct *data)
 {
        struct xfrm_state *x;
        struct hlist_node *entry, *tmp;
@@ -229,15 +230,16 @@ static inline unsigned long make_jiffies(long secs)
        if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
                return MAX_SCHEDULE_TIMEOUT-1;
        else
-               return secs*HZ;
+               return secs*HZ;
 }
 
 static void xfrm_timer_handler(unsigned long data)
 {
        struct xfrm_state *x = (struct xfrm_state*)data;
-       unsigned long now = (unsigned long)xtime.tv_sec;
+       unsigned long now = get_seconds();
        long next = LONG_MAX;
        int warn = 0;
+       int err = 0;
 
        spin_lock(&x->lock);
        if (x->km.state == XFRM_STATE_DEAD)
@@ -295,9 +297,14 @@ expired:
                next = 2;
                goto resched;
        }
-       if (!__xfrm_state_delete(x) && x->id.spi)
+
+       err = __xfrm_state_delete(x);
+       if (!err && x->id.spi)
                km_state_expired(x, 1, 0);
 
+       xfrm_audit_log(audit_get_loginuid(current->audit_context), 0,
+                      AUDIT_MAC_IPSEC_DELSA, err ? 0 : 1, NULL, x);
+
 out:
        spin_unlock(&x->lock);
 }
@@ -322,7 +329,7 @@ struct xfrm_state *xfrm_state_alloc(void)
                init_timer(&x->rtimer);
                x->rtimer.function = xfrm_replay_timer_handler;
                x->rtimer.data     = (unsigned long)x;
-               x->curlft.add_time = (unsigned long)xtime.tv_sec;
+               x->curlft.add_time = get_seconds();
                x->lft.soft_byte_limit = XFRM_INF;
                x->lft.soft_packet_limit = XFRM_INF;
                x->lft.hard_byte_limit = XFRM_INF;
@@ -384,11 +391,48 @@ int xfrm_state_delete(struct xfrm_state *x)
 }
 EXPORT_SYMBOL(xfrm_state_delete);
 
-void xfrm_state_flush(u8 proto)
+#ifdef CONFIG_SECURITY_NETWORK_XFRM
+static inline int
+xfrm_state_flush_secctx_check(u8 proto, struct xfrm_audit *audit_info)
 {
-       int i;
+       int i, err = 0;
+
+       for (i = 0; i <= xfrm_state_hmask; i++) {
+               struct hlist_node *entry;
+               struct xfrm_state *x;
+
+               hlist_for_each_entry(x, entry, xfrm_state_bydst+i, bydst) {
+                       if (xfrm_id_proto_match(x->id.proto, proto) &&
+                          (err = security_xfrm_state_delete(x)) != 0) {
+                               xfrm_audit_log(audit_info->loginuid,
+                                              audit_info->secid,
+                                              AUDIT_MAC_IPSEC_DELSA,
+                                               0, NULL, x);
+
+                               return err;
+                       }
+               }
+       }
+
+       return err;
+}
+#else
+static inline int
+xfrm_state_flush_secctx_check(u8 proto, struct xfrm_audit *audit_info)
+{
+       return 0;
+}
+#endif
+
+int xfrm_state_flush(u8 proto, struct xfrm_audit *audit_info)
+{
+       int i, err = 0;
 
        spin_lock_bh(&xfrm_state_lock);
+       err = xfrm_state_flush_secctx_check(proto, audit_info);
+       if (err)
+               goto out;
+
        for (i = 0; i <= xfrm_state_hmask; i++) {
                struct hlist_node *entry;
                struct xfrm_state *x;
@@ -399,7 +443,11 @@ restart:
                                xfrm_state_hold(x);
                                spin_unlock_bh(&xfrm_state_lock);
 
-                               xfrm_state_delete(x);
+                               err = xfrm_state_delete(x);
+                               xfrm_audit_log(audit_info->loginuid,
+                                              audit_info->secid,
+                                              AUDIT_MAC_IPSEC_DELSA,
+                                              err ? 0 : 1, NULL, x);
                                xfrm_state_put(x);
 
                                spin_lock_bh(&xfrm_state_lock);
@@ -407,11 +455,25 @@ restart:
                        }
                }
        }
+       err = 0;
+
+out:
        spin_unlock_bh(&xfrm_state_lock);
        wake_up(&km_waitq);
+       return err;
 }
 EXPORT_SYMBOL(xfrm_state_flush);
 
+void xfrm_sad_getinfo(struct xfrmk_sadinfo *si)
+{
+       spin_lock_bh(&xfrm_state_lock);
+       si->sadcnt = xfrm_state_num;
+       si->sadhcnt = xfrm_state_hmask;
+       si->sadhmcnt = xfrm_state_hashmax;
+       spin_unlock_bh(&xfrm_state_lock);
+}
+EXPORT_SYMBOL(xfrm_sad_getinfo);
+
 static int
 xfrm_init_tempsel(struct xfrm_state *x, struct flowi *fl,
                  struct xfrm_tmpl *tmpl,
@@ -449,7 +511,7 @@ static struct xfrm_state *__xfrm_state_lookup(xfrm_address_t *daddr, __be32 spi,
                                             x->id.daddr.a6))
                                continue;
                        break;
-               };
+               }
 
                xfrm_state_hold(x);
                return x;
@@ -484,7 +546,7 @@ static struct xfrm_state *__xfrm_state_lookup_byaddr(xfrm_address_t *daddr, xfrm
                                             x->props.saddr.a6))
                                continue;
                        break;
-               };
+               }
 
                xfrm_state_hold(x);
                return x;
@@ -514,7 +576,7 @@ static void xfrm_hash_grow_check(int have_hash_collision)
 }
 
 struct xfrm_state *
-xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr, 
+xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr,
                struct flowi *fl, struct xfrm_tmpl *tmpl,
                struct xfrm_policy *pol, int *err,
                unsigned short family)
@@ -525,7 +587,7 @@ xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr,
        int acquire_in_progress = 0;
        int error = 0;
        struct xfrm_state *best = NULL;
-       
+
        spin_lock_bh(&xfrm_state_lock);
        hlist_for_each_entry(x, entry, xfrm_state_bydst+h, bydst) {
                if (x->props.family == family &&
@@ -561,7 +623,7 @@ xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr,
                                acquire_in_progress = 1;
                        } else if (x->km.state == XFRM_STATE_ERROR ||
                                   x->km.state == XFRM_STATE_EXPIRED) {
-                               if (xfrm_selector_match(&x->sel, fl, family) &&
+                               if (xfrm_selector_match(&x->sel, fl, family) &&
                                    security_xfrm_state_pol_flow_match(x, pol, fl))
                                        error = -ESRCH;
                        }
@@ -603,8 +665,8 @@ xfrm_state_find(xfrm_address_t *daddr, xfrm_address_t *saddr,
                                h = xfrm_spi_hash(&x->id.daddr, x->id.spi, x->id.proto, family);
                                hlist_add_head(&x->byspi, xfrm_state_byspi+h);
                        }
-                       x->lft.hard_add_expires_seconds = XFRM_ACQ_EXPIRES;
-                       x->timer.expires = jiffies + XFRM_ACQ_EXPIRES*HZ;
+                       x->lft.hard_add_expires_seconds = sysctl_xfrm_acq_expires;
+                       x->timer.expires = jiffies + sysctl_xfrm_acq_expires*HZ;
                        add_timer(&x->timer);
                        xfrm_state_num++;
                        xfrm_hash_grow_check(x->bydst.next != NULL);
@@ -695,7 +757,8 @@ static struct xfrm_state *__find_acq_core(unsigned short family, u8 mode, u32 re
                    x->props.mode   != mode ||
                    x->props.family != family ||
                    x->km.state     != XFRM_STATE_ACQ ||
-                   x->id.spi       != 0)
+                   x->id.spi       != 0 ||
+                   x->id.proto     != proto)
                        continue;
 
                switch (family) {
@@ -712,7 +775,7 @@ static struct xfrm_state *__find_acq_core(unsigned short family, u8 mode, u32 re
                                             (struct in6_addr *)saddr))
                                continue;
                        break;
-               };
+               }
 
                xfrm_state_hold(x);
                return x;
@@ -745,16 +808,16 @@ static struct xfrm_state *__find_acq_core(unsigned short family, u8 mode, u32 re
                        ipv6_addr_copy((struct in6_addr *)x->id.daddr.a6,
                                       (struct in6_addr *)daddr);
                        break;
-               };
+               }
 
                x->km.state = XFRM_STATE_ACQ;
                x->id.proto = proto;
                x->props.family = family;
                x->props.mode = mode;
                x->props.reqid = reqid;
-               x->lft.hard_add_expires_seconds = XFRM_ACQ_EXPIRES;
+               x->lft.hard_add_expires_seconds = sysctl_xfrm_acq_expires;
                xfrm_state_hold(x);
-               x->timer.expires = jiffies + XFRM_ACQ_EXPIRES*HZ;
+               x->timer.expires = jiffies + sysctl_xfrm_acq_expires*HZ;
                add_timer(&x->timer);
                hlist_add_head(&x->bydst, xfrm_state_bydst+h);
                h = xfrm_src_hash(daddr, saddr, family);
@@ -792,7 +855,8 @@ int xfrm_state_add(struct xfrm_state *x)
 
        if (use_spi && x->km.seq) {
                x1 = __xfrm_find_acq_byseq(x->km.seq);
-               if (x1 && xfrm_addr_cmp(&x1->id.daddr, &x->id.daddr, family)) {
+               if (x1 && ((x1->id.proto != x->id.proto) ||
+                   xfrm_addr_cmp(&x1->id.daddr, &x->id.daddr, family))) {
                        xfrm_state_put(x1);
                        x1 = NULL;
                }
@@ -819,6 +883,160 @@ out:
 }
 EXPORT_SYMBOL(xfrm_state_add);
 
+#ifdef CONFIG_XFRM_MIGRATE
+struct xfrm_state *xfrm_state_clone(struct xfrm_state *orig, int *errp)
+{
+       int err = -ENOMEM;
+       struct xfrm_state *x = xfrm_state_alloc();
+       if (!x)
+               goto error;
+
+       memcpy(&x->id, &orig->id, sizeof(x->id));
+       memcpy(&x->sel, &orig->sel, sizeof(x->sel));
+       memcpy(&x->lft, &orig->lft, sizeof(x->lft));
+       x->props.mode = orig->props.mode;
+       x->props.replay_window = orig->props.replay_window;
+       x->props.reqid = orig->props.reqid;
+       x->props.family = orig->props.family;
+       x->props.saddr = orig->props.saddr;
+
+       if (orig->aalg) {
+               x->aalg = xfrm_algo_clone(orig->aalg);
+               if (!x->aalg)
+                       goto error;
+       }
+       x->props.aalgo = orig->props.aalgo;
+
+       if (orig->ealg) {
+               x->ealg = xfrm_algo_clone(orig->ealg);
+               if (!x->ealg)
+                       goto error;
+       }
+       x->props.ealgo = orig->props.ealgo;
+
+       if (orig->calg) {
+               x->calg = xfrm_algo_clone(orig->calg);
+               if (!x->calg)
+                       goto error;
+       }
+       x->props.calgo = orig->props.calgo;
+
+       if (orig->encap) {
+               x->encap = kmemdup(orig->encap, sizeof(*x->encap), GFP_KERNEL);
+               if (!x->encap)
+                       goto error;
+       }
+
+       if (orig->coaddr) {
+               x->coaddr = kmemdup(orig->coaddr, sizeof(*x->coaddr),
+                                   GFP_KERNEL);
+               if (!x->coaddr)
+                       goto error;
+       }
+
+       err = xfrm_init_state(x);
+       if (err)
+               goto error;
+
+       x->props.flags = orig->props.flags;
+
+       x->curlft.add_time = orig->curlft.add_time;
+       x->km.state = orig->km.state;
+       x->km.seq = orig->km.seq;
+
+       return x;
+
+ error:
+       if (errp)
+               *errp = err;
+       if (x) {
+               kfree(x->aalg);
+               kfree(x->ealg);
+               kfree(x->calg);
+               kfree(x->encap);
+               kfree(x->coaddr);
+       }
+       kfree(x);
+       return NULL;
+}
+EXPORT_SYMBOL(xfrm_state_clone);
+
+/* xfrm_state_lock is held */
+struct xfrm_state * xfrm_migrate_state_find(struct xfrm_migrate *m)
+{
+       unsigned int h;
+       struct xfrm_state *x;
+       struct hlist_node *entry;
+
+       if (m->reqid) {
+               h = xfrm_dst_hash(&m->old_daddr, &m->old_saddr,
+                                 m->reqid, m->old_family);
+               hlist_for_each_entry(x, entry, xfrm_state_bydst+h, bydst) {
+                       if (x->props.mode != m->mode ||
+                           x->id.proto != m->proto)
+                               continue;
+                       if (m->reqid && x->props.reqid != m->reqid)
+                               continue;
+                       if (xfrm_addr_cmp(&x->id.daddr, &m->old_daddr,
+                                         m->old_family) ||
+                           xfrm_addr_cmp(&x->props.saddr, &m->old_saddr,
+                                         m->old_family))
+                               continue;
+                       xfrm_state_hold(x);
+                       return x;
+               }
+       } else {
+               h = xfrm_src_hash(&m->old_daddr, &m->old_saddr,
+                                 m->old_family);
+               hlist_for_each_entry(x, entry, xfrm_state_bysrc+h, bysrc) {
+                       if (x->props.mode != m->mode ||
+                           x->id.proto != m->proto)
+                               continue;
+                       if (xfrm_addr_cmp(&x->id.daddr, &m->old_daddr,
+                                         m->old_family) ||
+                           xfrm_addr_cmp(&x->props.saddr, &m->old_saddr,
+                                         m->old_family))
+                               continue;
+                       xfrm_state_hold(x);
+                       return x;
+               }
+       }
+
+       return NULL;
+}
+EXPORT_SYMBOL(xfrm_migrate_state_find);
+
+struct xfrm_state * xfrm_state_migrate(struct xfrm_state *x,
+                                      struct xfrm_migrate *m)
+{
+       struct xfrm_state *xc;
+       int err;
+
+       xc = xfrm_state_clone(x, &err);
+       if (!xc)
+               return NULL;
+
+       memcpy(&xc->id.daddr, &m->new_daddr, sizeof(xc->id.daddr));
+       memcpy(&xc->props.saddr, &m->new_saddr, sizeof(xc->props.saddr));
+
+       /* add state */
+       if (!xfrm_addr_cmp(&x->id.daddr, &m->new_daddr, m->new_family)) {
+               /* a care is needed when the destination address of the
+                  state is to be updated as it is a part of triplet */
+               xfrm_state_insert(xc);
+       } else {
+               if ((err = xfrm_state_add(xc)) < 0)
+                       goto error;
+       }
+
+       return xc;
+error:
+       kfree(xc);
+       return NULL;
+}
+EXPORT_SYMBOL(xfrm_state_migrate);
+#endif
+
 int xfrm_state_update(struct xfrm_state *x)
 {
        struct xfrm_state *x1;
@@ -886,7 +1104,7 @@ EXPORT_SYMBOL(xfrm_state_update);
 int xfrm_state_check_expire(struct xfrm_state *x)
 {
        if (!x->curlft.use_time)
-               x->curlft.use_time = (unsigned long)xtime.tv_sec;
+               x->curlft.use_time = get_seconds();
 
        if (x->km.state != XFRM_STATE_VALID)
                return -EINVAL;
@@ -958,8 +1176,8 @@ xfrm_state_lookup_byaddr(xfrm_address_t *daddr, xfrm_address_t *saddr,
 EXPORT_SYMBOL(xfrm_state_lookup_byaddr);
 
 struct xfrm_state *
-xfrm_find_acq(u8 mode, u32 reqid, u8 proto, 
-             xfrm_address_t *daddr, xfrm_address_t *saddr, 
+xfrm_find_acq(u8 mode, u32 reqid, u8 proto,
+             xfrm_address_t *daddr, xfrm_address_t *saddr,
              int create, unsigned short family)
 {
        struct xfrm_state *x;
@@ -1099,7 +1317,7 @@ int xfrm_state_walk(u8 proto, int (*func)(struct xfrm_state *, int, void*),
                    void *data)
 {
        int i;
-       struct xfrm_state *x;
+       struct xfrm_state *x, *last = NULL;
        struct hlist_node *entry;
        int count = 0;
        int err = 0;
@@ -1107,24 +1325,22 @@ int xfrm_state_walk(u8 proto, int (*func)(struct xfrm_state *, int, void*),
        spin_lock_bh(&xfrm_state_lock);
        for (i = 0; i <= xfrm_state_hmask; i++) {
                hlist_for_each_entry(x, entry, xfrm_state_bydst+i, bydst) {
-                       if (xfrm_id_proto_match(x->id.proto, proto))
-                               count++;
+                       if (!xfrm_id_proto_match(x->id.proto, proto))
+                               continue;
+                       if (last) {
+                               err = func(last, count, data);
+                               if (err)
+                                       goto out;
+                       }
+                       last = x;
+                       count++;
                }
        }
        if (count == 0) {
                err = -ENOENT;
                goto out;
        }
-
-       for (i = 0; i <= xfrm_state_hmask; i++) {
-               hlist_for_each_entry(x, entry, xfrm_state_bydst+i, bydst) {
-                       if (!xfrm_id_proto_match(x->id.proto, proto))
-                               continue;
-                       err = func(x, --count, data);
-                       if (err)
-                               goto out;
-               }
-       }
+       err = func(last, 0, data);
 out:
        spin_unlock_bh(&xfrm_state_lock);
        return err;
@@ -1208,7 +1424,8 @@ int xfrm_replay_check(struct xfrm_state *x, __be32 net_seq)
                return 0;
 
        diff = x->replay.seq - seq;
-       if (diff >= x->props.replay_window) {
+       if (diff >= min_t(unsigned int, x->props.replay_window,
+                         sizeof(x->replay.bitmap) * 8)) {
                x->stats.replay_window++;
                return -EINVAL;
        }
@@ -1304,7 +1521,7 @@ int km_query(struct xfrm_state *x, struct xfrm_tmpl *t, struct xfrm_policy *pol)
 }
 EXPORT_SYMBOL(km_query);
 
-int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, u16 sport)
+int km_new_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr, __be16 sport)
 {
        int err = -EINVAL;
        struct xfrm_mgr *km;
@@ -1335,6 +1552,26 @@ void km_policy_expired(struct xfrm_policy *pol, int dir, int hard, u32 pid)
 }
 EXPORT_SYMBOL(km_policy_expired);
 
+int km_migrate(struct xfrm_selector *sel, u8 dir, u8 type,
+              struct xfrm_migrate *m, int num_migrate)
+{
+       int err = -EINVAL;
+       int ret;
+       struct xfrm_mgr *km;
+
+       read_lock(&xfrm_km_lock);
+       list_for_each_entry(km, &xfrm_km_list, list) {
+               if (km->migrate) {
+                       ret = km->migrate(sel, dir, type, m, num_migrate);
+                       if (!ret)
+                               err = ret;
+               }
+       }
+       read_unlock(&xfrm_km_lock);
+       return err;
+}
+EXPORT_SYMBOL(km_migrate);
+
 int km_report(u8 proto, struct xfrm_selector *sel, xfrm_address_t *addr)
 {
        int err = -EINVAL;
@@ -1448,7 +1685,7 @@ int xfrm_state_unregister_afinfo(struct xfrm_state_afinfo *afinfo)
 }
 EXPORT_SYMBOL(xfrm_state_unregister_afinfo);
 
-static struct xfrm_state_afinfo *xfrm_state_get_afinfo(unsigned short family)
+struct xfrm_state_afinfo *xfrm_state_get_afinfo(unsigned short family)
 {
        struct xfrm_state_afinfo *afinfo;
        if (unlikely(family >= NPROTO))
@@ -1460,11 +1697,14 @@ static struct xfrm_state_afinfo *xfrm_state_get_afinfo(unsigned short family)
        return afinfo;
 }
 
-static void xfrm_state_put_afinfo(struct xfrm_state_afinfo *afinfo)
+void xfrm_state_put_afinfo(struct xfrm_state_afinfo *afinfo)
 {
        read_unlock(&xfrm_state_afinfo_lock);
 }
 
+EXPORT_SYMBOL(xfrm_state_get_afinfo);
+EXPORT_SYMBOL(xfrm_state_put_afinfo);
+
 /* Temporarily located here until net/xfrm/xfrm_tunnel.c is created */
 void xfrm_state_delete_tunnel(struct xfrm_state *x)
 {
@@ -1480,37 +1720,17 @@ void xfrm_state_delete_tunnel(struct xfrm_state *x)
 }
 EXPORT_SYMBOL(xfrm_state_delete_tunnel);
 
-/*
- * This function is NOT optimal.  For example, with ESP it will give an
- * MTU that's usually two bytes short of being optimal.  However, it will
- * usually give an answer that's a multiple of 4 provided the input is
- * also a multiple of 4.
- */
 int xfrm_state_mtu(struct xfrm_state *x, int mtu)
 {
-       int res = mtu;
-
-       res -= x->props.header_len;
-
-       for (;;) {
-               int m = res;
-
-               if (m < 68)
-                       return 68;
-
-               spin_lock_bh(&x->lock);
-               if (x->km.state == XFRM_STATE_VALID &&
-                   x->type && x->type->get_max_size)
-                       m = x->type->get_max_size(x, m);
-               else
-                       m += x->props.header_len;
-               spin_unlock_bh(&x->lock);
-
-               if (m <= mtu)
-                       break;
-               res -= (m - mtu);
-       }
+       int res;
 
+       spin_lock_bh(&x->lock);
+       if (x->km.state == XFRM_STATE_VALID &&
+           x->type && x->type->get_mtu)
+               res = x->type->get_mtu(x, mtu);
+       else
+               res = mtu - x->props.header_len;
+       spin_unlock_bh(&x->lock);
        return res;
 }
 
@@ -1554,7 +1774,7 @@ error:
 }
 
 EXPORT_SYMBOL(xfrm_init_state);
+
 void __init xfrm_state_init(void)
 {
        unsigned int sz;
@@ -1568,6 +1788,6 @@ void __init xfrm_state_init(void)
                panic("XFRM: Cannot allocate bydst/bysrc/byspi hashes.");
        xfrm_state_hmask = ((sz / sizeof(struct hlist_head)) - 1);
 
-       INIT_WORK(&xfrm_state_gc_work, xfrm_state_gc_task, NULL);
+       INIT_WORK(&xfrm_state_gc_work, xfrm_state_gc_task);
 }