summaryrefslogtreecommitdiff
path: root/net/ipv6/ip6_flowlabel.c
diff options
context:
space:
mode:
authorEric Dumazet <edumazet@google.com>2019-06-06 14:32:34 -0700
committerDavid S. Miller <davem@davemloft.net>2019-06-09 13:07:14 -0700
commit65a3c497c0e965a552008db8bc2653f62bc925a1 (patch)
treeb3123d60841736cf01855d36332b3f0410a3129b /net/ipv6/ip6_flowlabel.c
parentc3fee640bcf52c34a25b767f2b0eda82e97a1f3b (diff)
ipv6: flowlabel: fl6_sock_lookup() must use atomic_inc_not_zero
Before taking a refcount, make sure the object is not already scheduled for deletion. Same fix is needed in ipv6_flowlabel_opt() Fixes: 18367681a10b ("ipv6 flowlabel: Convert np->ipv6_fl_list to RCU.") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6/ip6_flowlabel.c')
-rw-r--r--net/ipv6/ip6_flowlabel.c7
1 files changed, 4 insertions, 3 deletions
diff --git a/net/ipv6/ip6_flowlabel.c b/net/ipv6/ip6_flowlabel.c
index 2f3eb7dc45da..545e339b8c4f 100644
--- a/net/ipv6/ip6_flowlabel.c
+++ b/net/ipv6/ip6_flowlabel.c
@@ -250,9 +250,9 @@ struct ip6_flowlabel *fl6_sock_lookup(struct sock *sk, __be32 label)
rcu_read_lock_bh();
for_each_sk_fl_rcu(np, sfl) {
struct ip6_flowlabel *fl = sfl->fl;
- if (fl->label == label) {
+
+ if (fl->label == label && atomic_inc_not_zero(&fl->users)) {
fl->lastuse = jiffies;
- atomic_inc(&fl->users);
rcu_read_unlock_bh();
return fl;
}
@@ -618,7 +618,8 @@ int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
goto done;
}
fl1 = sfl->fl;
- atomic_inc(&fl1->users);
+ if (!atomic_inc_not_zero(&fl1->users))
+ fl1 = NULL;
break;
}
}