Release 4.11 net/ipv6/ip6_flowlabel.c

/*
 *      ip6_flowlabel.c         IPv6 flowlabel manager.
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 *
 *      Authors:        Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 */

#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/in6.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/pid_namespace.h>

#include <net/net_namespace.h>
#include <net/sock.h>

#include <net/ipv6.h>
#include <net/rawv6.h>
#include <net/transp_v6.h>

#include <linux/uaccess.h>


#define FL_MIN_LINGER	6	
/* Minimal linger. It is set to 6sec specified
                                   in old IPv6 RFC. Well, it was reasonable value.
                                 */

#define FL_MAX_LINGER	150	
/* Maximal linger timeout */

/* FL hash table */


#define FL_MAX_PER_SOCK	32

#define FL_MAX_SIZE	4096

#define FL_HASH_MASK	255

#define FL_HASH(l)	(ntohl(l)&FL_HASH_MASK)


static atomic_t fl_size = ATOMIC_INIT(0);

static struct ip6_flowlabel __rcu *fl_ht[FL_HASH_MASK+1];

static void ip6_fl_gc(unsigned long dummy);
static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc, 0, 0);

/* FL hash table lock: it protects only of GC */

static DEFINE_SPINLOCK(ip6_fl_lock);

/* Big socket sock */

static DEFINE_SPINLOCK(ip6_sk_fl_lock);


#define for_each_fl_rcu(hash, fl)				\
	for (fl = rcu_dereference_bh(fl_ht[(hash)]);            \
             fl != NULL;                                        \
             fl = rcu_dereference_bh(fl->next))

#define for_each_fl_continue_rcu(fl)				\
	for (fl = rcu_dereference_bh(fl->next);                 \
             fl != NULL;                                        \
             fl = rcu_dereference_bh(fl->next))


#define for_each_sk_fl_rcu(np, sfl)				\
	for (sfl = rcu_dereference_bh(np->ipv6_fl_list);        \
             sfl != NULL;                                       \
             sfl = rcu_dereference_bh(sfl->next))



static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label)
{
	struct ip6_flowlabel *fl;

	for_each_fl_rcu(FL_HASH(label), fl) {
		if (fl->label == label && net_eq(fl->fl_net, net))
			return fl;
	}
	return NULL;
}

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Linus Torvalds (pre-git)
23
43.40%
2
40.00%
Benjamin Thery
22
41.51%
1
20.00%
Octavian Purdila
4
7.55%
1
20.00%
Hideaki Yoshifuji / 吉藤英明
4
7.55%
1
20.00%
Total
53
100.00%
5
100.00%



static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label)
{
	struct ip6_flowlabel *fl;

	rcu_read_lock_bh();
	fl = __fl_lookup(net, label);
	if (fl && !atomic_inc_not_zero(&fl->users))
		fl = NULL;
	rcu_read_unlock_bh();
	return fl;
}


Contributors
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Linus Torvalds (pre-git)
36
64.29%
2
40.00%
Hideaki Yoshifuji / 吉藤英明
11
19.64%
1
20.00%
Benjamin Thery
8
14.29%
1
20.00%
Al Viro
1
1.79%
1
20.00%
Total
56
100.00%
5
100.00%



static void fl_free(struct ip6_flowlabel *fl)
{
	if (fl) {
		if (fl->share == IPV6_FL_S_PROCESS)
			put_pid(fl->owner.pid);
		kfree(fl->opt);
		kfree_rcu(fl, rcu);
	}
}

Contributors
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Linus Torvalds (pre-git)
22
45.83%
1
25.00%
Eric W. Biedermann
14
29.17%
1
25.00%
Dan Carpenter
8
16.67%
1
25.00%
Hideaki Yoshifuji / 吉藤英明
4
8.33%
1
25.00%
Total
48
100.00%
4
100.00%



static void fl_release(struct ip6_flowlabel *fl)
{
	spin_lock_bh(&ip6_fl_lock);

	fl->lastuse = jiffies;
	if (atomic_dec_and_test(&fl->users)) {
		unsigned long ttd = fl->lastuse + fl->linger;
		if (time_after(ttd, fl->expires))
			fl->expires = ttd;
		ttd = fl->expires;
		if (fl->opt && fl->share == IPV6_FL_S_EXCL) {
			struct ipv6_txoptions *opt = fl->opt;
			fl->opt = NULL;
			kfree(opt);
		}
		if (!timer_pending(&ip6_fl_gc_timer) ||
		    time_after(ip6_fl_gc_timer.expires, ttd))
			mod_timer(&ip6_fl_gc_timer, ttd);
	}
	spin_unlock_bh(&ip6_fl_lock);
}

Contributors
Person
Tokens
Prop
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CommitProp
Linus Torvalds (pre-git)
117
86.03%
1
33.33%
Vinay K. Nallamothu
17
12.50%
1
33.33%
Hideaki Yoshifuji / 吉藤英明
2
1.47%
1
33.33%
Total
136
100.00%
3
100.00%



static void ip6_fl_gc(unsigned long dummy)
{
	int i;
	unsigned long now = jiffies;
	unsigned long sched = 0;

	spin_lock(&ip6_fl_lock);

	for (i = 0; i <= FL_HASH_MASK; i++) {
		struct ip6_flowlabel *fl;
		struct ip6_flowlabel __rcu **flp;

		flp = &fl_ht[i];
		while ((fl = rcu_dereference_protected(*flp,
						       lockdep_is_held(&ip6_fl_lock))) != NULL) {
			if (atomic_read(&fl->users) == 0) {
				unsigned long ttd = fl->lastuse + fl->linger;
				if (time_after(ttd, fl->expires))
					fl->expires = ttd;
				ttd = fl->expires;
				if (time_after_eq(now, ttd)) {
					*flp = fl->next;
					fl_free(fl);
					atomic_dec(&fl_size);
					continue;
				}
				if (!sched || time_before(ttd, sched))
					sched = ttd;
			}
			flp = &fl->next;
		}
	}
	if (!sched && atomic_read(&fl_size))
		sched = now + FL_MAX_LINGER;
	if (sched) {
		mod_timer(&ip6_fl_gc_timer, sched);
	}
	spin_unlock(&ip6_fl_lock);
}

Contributors
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Tokens
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Commits
CommitProp
Linus Torvalds (pre-git)
199
87.67%
1
20.00%
Hideaki Yoshifuji / 吉藤英明
11
4.85%
1
20.00%
Benjamin Thery
7
3.08%
1
20.00%
Vinay K. Nallamothu
6
2.64%
1
20.00%
Eric Dumazet
4
1.76%
1
20.00%
Total
227
100.00%
5
100.00%



static void __net_exit ip6_fl_purge(struct net *net)
{
	int i;

	spin_lock_bh(&ip6_fl_lock);
	for (i = 0; i <= FL_HASH_MASK; i++) {
		struct ip6_flowlabel *fl;
		struct ip6_flowlabel __rcu **flp;

		flp = &fl_ht[i];
		while ((fl = rcu_dereference_protected(*flp,
						       lockdep_is_held(&ip6_fl_lock))) != NULL) {
			if (net_eq(fl->fl_net, net) &&
			    atomic_read(&fl->users) == 0) {
				*flp = fl->next;
				fl_free(fl);
				atomic_dec(&fl_size);
				continue;
			}
			flp = &fl->next;
		}
	}
	spin_unlock_bh(&ip6_fl_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Benjamin Thery
107
80.45%
1
12.50%
Hideaki Yoshifuji / 吉藤英明
9
6.77%
1
12.50%
Linus Torvalds (pre-git)
6
4.51%
2
25.00%
Eric Dumazet
4
3.01%
1
12.50%
Octavian Purdila
4
3.01%
1
12.50%
Jan Stancek
2
1.50%
1
12.50%
Alexey Dobriyan
1
0.75%
1
12.50%
Total
133
100.00%
8
100.00%



static struct ip6_flowlabel *fl_intern(struct net *net,
				       struct ip6_flowlabel *fl, __be32 label)
{
	struct ip6_flowlabel *lfl;

	fl->label = label & IPV6_FLOWLABEL_MASK;

	spin_lock_bh(&ip6_fl_lock);
	if (label == 0) {
		for (;;) {
			fl->label = htonl(prandom_u32())&IPV6_FLOWLABEL_MASK;
			if (fl->label) {
				lfl = __fl_lookup(net, fl->label);
				if (!lfl)
					break;
			}
		}
	} else {
		/*
                 * we dropper the ip6_fl_lock, so this entry could reappear
                 * and we need to recheck with it.
                 *
                 * OTOH no need to search the active socket first, like it is
                 * done in ipv6_flowlabel_opt - sock is locked, so new entry
                 * with the same label can only appear on another sock
                 */
		lfl = __fl_lookup(net, fl->label);
		if (lfl) {
			atomic_inc(&lfl->users);
			spin_unlock_bh(&ip6_fl_lock);
			return lfl;
		}
	}

	fl->lastuse = jiffies;
	fl->next = fl_ht[FL_HASH(fl->label)];
	rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl);
	atomic_inc(&fl_size);
	spin_unlock_bh(&ip6_fl_lock);
	return NULL;
}



Contributors
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CommitProp
Linus Torvalds (pre-git)
117
65.00%
2
25.00%
Pavel Emelyanov
44
24.44%
1
12.50%
Benjamin Thery
9
5.00%
1
12.50%
Hideaki Yoshifuji / 吉藤英明
7
3.89%
1
12.50%
Al Viro
1
0.56%
1
12.50%
Aruna-Hewapathirane
1
0.56%
1
12.50%
Ian Morris
1
0.56%
1
12.50%
Total
180
100.00%
8
100.00%

/* Socket flowlabel lists */



struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label)
{
	struct ipv6_fl_socklist *sfl;
	struct ipv6_pinfo *np = inet6_sk(sk);

	label &= IPV6_FLOWLABEL_MASK;

	rcu_read_lock_bh();
	for_each_sk_fl_rcu(np, sfl) {
		struct ip6_flowlabel *fl = sfl->fl;
		if (fl->label == label) {
			fl->lastuse = jiffies;
			atomic_inc(&fl->users);
			rcu_read_unlock_bh();
			return fl;
		}
	}
	rcu_read_unlock_bh();
	return NULL;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
71
78.89%
1
16.67%
Hideaki Yoshifuji / 吉藤英明
11
12.22%
1
16.67%
Pavel Emelyanov
4
4.44%
2
33.33%
David S. Miller
3
3.33%
1
16.67%
Al Viro
1
1.11%
1
16.67%
Total
90
100.00%
6
100.00%


EXPORT_SYMBOL_GPL(fl6_sock_lookup);



void fl6_free_socklist(struct sock *sk)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct ipv6_fl_socklist *sfl;

	if (!rcu_access_pointer(np->ipv6_fl_list))
		return;

	spin_lock_bh(&ip6_sk_fl_lock);
	while ((sfl = rcu_dereference_protected(np->ipv6_fl_list,
						lockdep_is_held(&ip6_sk_fl_lock))) != NULL) {
		np->ipv6_fl_list = sfl->next;
		spin_unlock_bh(&ip6_sk_fl_lock);

		fl_release(sfl->fl);
		kfree_rcu(sfl, rcu);

		spin_lock_bh(&ip6_sk_fl_lock);
	}
	spin_unlock_bh(&ip6_sk_fl_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Hideaki Yoshifuji / 吉藤英明
58
55.24%
2
50.00%
Linus Torvalds (pre-git)
44
41.90%
1
25.00%
David S. Miller
3
2.86%
1
25.00%
Total
105
100.00%
4
100.00%

/* Service routines */


/*
   It is the only difficult place. flowlabel enforces equal headers
   before and including routing header, however user may supply options
   following rthdr.
 */



struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space,
					 struct ip6_flowlabel *fl,
					 struct ipv6_txoptions *fopt)
{
	struct ipv6_txoptions *fl_opt = fl->opt;

	if (!fopt || fopt->opt_flen == 0)
		return fl_opt;

	if (fl_opt) {
		opt_space->hopopt = fl_opt->hopopt;
		opt_space->dst0opt = fl_opt->dst0opt;
		opt_space->srcrt = fl_opt->srcrt;
		opt_space->opt_nflen = fl_opt->opt_nflen;
	} else {
		if (fopt->opt_nflen == 0)
			return fopt;
		opt_space->hopopt = NULL;
		opt_space->dst0opt = NULL;
		opt_space->srcrt = NULL;
		opt_space->opt_nflen = 0;
	}
	opt_space->dst1opt = fopt->dst1opt;
	opt_space->opt_flen = fopt->opt_flen;
	return opt_space;
}
Contributors
Person
Tokens
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CommitProp
Linus Torvalds (pre-git)
139
99.29%
1
50.00%
Ian Morris
1
0.71%
1
50.00%
Total
140
100.00%
2
100.00%


EXPORT_SYMBOL_GPL(fl6_merge_options);



static unsigned long check_linger(unsigned long ttl)
{
	if (ttl < FL_MIN_LINGER)
		return FL_MIN_LINGER*HZ;
	if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN))
		return 0;
	return ttl*HZ;
}

Contributors
Person
Tokens
Prop
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CommitProp
Linus Torvalds (pre-git)
38
90.48%
1
50.00%
David S. Miller
4
9.52%
1
50.00%
Total
42
100.00%
2
100.00%



static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires)
{
	linger = check_linger(linger);
	if (!linger)
		return -EPERM;
	expires = check_linger(expires);
	if (!expires)
		return -EPERM;

	spin_lock_bh(&ip6_fl_lock);
	fl->lastuse = jiffies;
	if (time_before(fl->linger, linger))
		fl->linger = linger;
	if (time_before(expires, fl->linger))
		expires = fl->linger;
	if (time_before(fl->expires, fl->lastuse + expires))
		fl->expires = fl->lastuse + expires;
	spin_unlock_bh(&ip6_fl_lock);

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
107
81.68%
1
25.00%
Florent Fourcot
12
9.16%
1
25.00%
Vinay K. Nallamothu
10
7.63%
1
25.00%
David S. Miller
2
1.53%
1
25.00%
Total
131
100.00%
4
100.00%


static struct ip6_flowlabel *

fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq,
	  char __user *optval, int optlen, int *err_p)
{
	struct ip6_flowlabel *fl = NULL;
	int olen;
	int addr_type;
	int err;

	olen = optlen - CMSG_ALIGN(sizeof(*freq));
	err = -EINVAL;
	if (olen > 64 * 1024)
		goto done;

	err = -ENOMEM;
	fl = kzalloc(sizeof(*fl), GFP_KERNEL);
	if (!fl)
		goto done;

	if (olen > 0) {
		struct msghdr msg;
		struct flowi6 flowi6;
		struct sockcm_cookie sockc_junk;
		struct ipcm6_cookie ipc6;

		err = -ENOMEM;
		fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL);
		if (!fl->opt)
			goto done;

		memset(fl->opt, 0, sizeof(*fl->opt));
		fl->opt->tot_len = sizeof(*fl->opt) + olen;
		err = -EFAULT;
		if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen))
			goto done;

		msg.msg_controllen = olen;
		msg.msg_control = (void *)(fl->opt+1);
		memset(&flowi6, 0, sizeof(flowi6));

		ipc6.opt = fl->opt;
		err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, &ipc6, &sockc_junk);
		if (err)
			goto done;
		err = -EINVAL;
		if (fl->opt->opt_flen)
			goto done;
		if (fl->opt->opt_nflen == 0) {
			kfree(fl->opt);
			fl->opt = NULL;
		}
	}

	fl->fl_net = net;
	fl->expires = jiffies;
	err = fl6_renew(fl, freq->flr_linger, freq->flr_expires);
	if (err)
		goto done;
	fl->share = freq->flr_share;
	addr_type = ipv6_addr_type(&freq->flr_dst);
	if ((addr_type & IPV6_ADDR_MAPPED) ||
	    addr_type == IPV6_ADDR_ANY) {
		err = -EINVAL;
		goto done;
	}
	fl->dst = freq->flr_dst;
	atomic_set(&fl->users, 1);
	switch (fl->share) {
	case IPV6_FL_S_EXCL:
	case IPV6_FL_S_ANY:
		break;
	case IPV6_FL_S_PROCESS:
		fl->owner.pid = get_task_pid(current, PIDTYPE_PID);
		break;
	case IPV6_FL_S_USER:
		fl->owner.uid = current_euid();
		break;
	default:
		err = -EINVAL;
		goto done;
	}
	return fl;

done:
	fl_free(fl);
	*err_p = err;
	return NULL;
}

Contributors
Person
Tokens
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CommitProp
Linus Torvalds (pre-git)
396
78.42%
1
5.88%
David S. Miller
45
8.91%
2
11.76%
Wei Wang
12
2.38%
1
5.88%
Benjamin Thery
11
2.18%
1
5.88%
Eric W. Biedermann
9
1.78%
1
5.88%
James Morris
7
1.39%
1
5.88%
Maciej Żenczykowski
7
1.39%
1
5.88%
Soheil Hassas Yeganeh
7
1.39%
1
5.88%
Ian Morris
2
0.40%
1
5.88%
David Howells
2
0.40%
1
5.88%
Hideaki Yoshifuji / 吉藤英明
2
0.40%
1
5.88%
Brian Haley
1
0.20%
1
5.88%
Al Viro
1
0.20%
1
5.88%
Tom Parkin
1
0.20%
1
5.88%
Alexey Dobriyan
1
0.20%
1
5.88%
Ingo Oeser
1
0.20%
1
5.88%
Total
505
100.00%
17
100.00%



static int mem_check(struct sock *sk)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct ipv6_fl_socklist *sfl;
	int room = FL_MAX_SIZE - atomic_read(&fl_size);
	int count = 0;

	if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
		return 0;

	rcu_read_lock_bh();
	for_each_sk_fl_rcu(np, sfl)
		count++;
	rcu_read_unlock_bh();

	if (room <= 0 ||
	    ((count >= FL_MAX_PER_SOCK ||
	      (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) &&
	     !capable(CAP_NET_ADMIN)))
		return -ENOBUFS;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
91
80.53%
1
25.00%
David S. Miller
10
8.85%
1
25.00%
Hannes Frederic Sowa
6
5.31%
1
25.00%
Hideaki Yoshifuji / 吉藤英明
6
5.31%
1
25.00%
Total
113
100.00%
4
100.00%



static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl,
		struct ip6_flowlabel *fl)
{
	spin_lock_bh(&ip6_sk_fl_lock);
	sfl->fl = fl;
	sfl->next = np->ipv6_fl_list;
	rcu_assign_pointer(np->ipv6_fl_list, sfl);
	spin_unlock_bh(&ip6_sk_fl_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Pavel Emelyanov
51
89.47%
1
50.00%
Hideaki Yoshifuji / 吉藤英明
6
10.53%
1
50.00%
Total
57
100.00%
2
100.00%



int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
			   int flags)
{
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct ipv6_fl_socklist *sfl;

	if (flags & IPV6_FL_F_REMOTE) {
		freq->flr_label = np->rcv_flowinfo & IPV6_FLOWLABEL_MASK;
		return 0;
	}

	if (np->repflow) {
		freq->flr_label = np->flow_label;
		return 0;
	}

	rcu_read_lock_bh();

	for_each_sk_fl_rcu(np, sfl) {
		if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) {
			spin_lock_bh(&ip6_fl_lock);
			freq->flr_label = sfl->fl->label;
			freq->flr_dst = sfl->fl->dst;
			freq->flr_share = sfl->fl->share;
			freq->flr_expires = (sfl->fl->expires - jiffies) / HZ;
			freq->flr_linger = sfl->fl->linger / HZ;

			spin_unlock_bh(&ip6_fl_lock);
			rcu_read_unlock_bh();
			return 0;
		}
	}
	rcu_read_unlock_bh();

	return -ENOENT;
}

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Florent Fourcot
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int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
{
	int uninitialized_var(err);
	struct net *net = sock_net(sk);
	struct ipv6_pinfo *np = inet6_sk(sk);
	struct in6_flowlabel_req freq;
	struct ipv6_fl_socklist *sfl1 = NULL;
	struct ipv6_fl_socklist *sfl;
	struct ipv6_fl_socklist __rcu **sflp;
	struct ip6_flowlabel *fl, *fl1 = NULL;


	if (optlen < sizeof(freq))
		return -EINVAL;

	if (copy_from_user(&freq, optval, sizeof(freq)))
		return -EFAULT;

	switch (freq.flr_action) {
	case IPV6_FL_A_PUT:
		if (freq.flr_flags & IPV6_FL_F_REFLECT) {
			if (sk->sk_protocol != IPPROTO_TCP)
				return -ENOPROTOOPT;
			if (!np->repflow)
				return -ESRCH;
			np->flow_label = 0;
			np->repflow = 0;
			return 0;
		}
		spin_lock_bh(&ip6_sk_fl_lock);
		for (sflp = &np->ipv6_fl_list;
		     (sfl = rcu_dereference_protected(*sflp,
						      lockdep_is_held(&ip6_sk_fl_lock))) != NULL;
		     sflp = &sfl->next) {
			if (sfl->fl->label == freq.flr_label) {
				if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
					np->flow_label &= ~IPV6_FLOWLABEL_MASK;
				*sflp = sfl->next;
				spin_unlock_bh(&ip6_sk_fl_lock);
				fl_release(sfl->fl);
				kfree_rcu(sfl, rcu);
				return 0;
			}
		}
		spin_unlock_bh(&ip6_sk_fl_lock);
		return -ESRCH;

	case IPV6_FL_A_RENEW:
		rcu_read_lock_bh();
		for_each_sk_fl_rcu(np, sfl) {
			if (sfl->fl->label == freq.flr_label) {
				err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
				rcu_read_unlock_bh();
				return err;
			}
		}
		rcu_read_unlock_bh();

		if (freq.flr_share == IPV6_FL_S_NONE &&
		    ns_capable(net->user_ns, CAP_NET_ADMIN)) {
			fl = fl_lookup(net, freq.flr_label);
			if (fl) {
				err = fl6_renew(fl, freq.flr_linger, freq.flr_expires);
				fl_release(fl);
				return err;
			}
		}
		return -ESRCH;

	case IPV6_FL_A_GET:
		if (freq.flr_flags & IPV6_FL_F_REFLECT) {
			struct net *net = sock_net(sk);
			if (net->ipv6.sysctl.flowlabel_consistency) {
				net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n");
				return -EPERM;
			}

			if (sk->sk_protocol != IPPROTO_TCP)
				return -ENOPROTOOPT;

			np->repflow = 1;
			return 0;
		}

		if (freq.flr_label & ~IPV6_FLOWLABEL_MASK)
			return -EINVAL;

		if (net->ipv6.sysctl.flowlabel_state_ranges &&
		    (freq.flr_label & IPV6_FLOWLABEL_STATELESS_FLAG))
			return -ERANGE;

		fl = fl_create(net, sk, &freq, optval, optlen, &err);
		if (!fl)
			return err;
		sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);

		if (freq.flr_label) {
			err = -EEXIST;
			rcu_read_lock_bh();
			for_each_sk_fl_rcu(np, sfl) {
				if (sfl->fl->label == freq.flr_label) {
					if (freq.flr_flags&IPV6_FL_F_EXCL) {
						rcu_read_unlock_bh();
						goto done;
					}
					fl1 = sfl->fl;
					atomic_inc(&fl1->users);
					break;
				}
			}
			rcu_read_unlock_bh();

			if (!fl1)
				fl1 = fl_lookup(net, freq.flr_label);
			if (fl1) {
recheck:
				err = -EEXIST;
				if (freq.flr_flags&IPV6_FL_F_EXCL)
					goto release;
				err = -EPERM;
				if (fl1->share == IPV6_FL_S_EXCL ||
				    fl1->share != fl->