1 files changed, 36 insertions, 2 deletions

diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
index e7fb7106550f..dfa41bb4e0dc 100644
--- a/net/ipv6/ip6_flowlabel.c
+++ b/net/ipv6/ip6_flowlabel.c
@@ -210,7 +210,7 @@ static struct ip6_flowlabel *fl_intern(struct net *net,
         spin_lock_bh(&ip6_fl_lock);
         if (label == 0) {
                 for (;;) {
-                        fl->label = htonl(net_random())&IPV6_FLOWLABEL_MASK;
+                        fl->label = htonl(prandom_u32())&IPV6_FLOWLABEL_MASK;
                         if (fl->label) {
                                 lfl = __fl_lookup(net, fl->label);
                                 if (lfl == NULL)
@@ -481,11 +481,22 @@ static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl,
         spin_unlock_bh(&ip6_sk_fl_lock);
 }
 
-int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq)
+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) {
@@ -527,6 +538,15 @@ int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
 
         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(*sflp))!=NULL;
@@ -567,6 +587,20 @@ int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
                 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;