3.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Eric Dumazet <edumazet@xxxxxxxxxx>
commit c836a8ba93869d6a0290a6ae0047fbef09066871 upstream.
This patch completes the work I did in commit 45f6fad84cc3
("ipv6: add complete rcu protection around np->opt"), as I missed
sctp part.
This simply makes sure np->opt is used with proper RCU locking
and accessors.
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Amit Pundir <amit.pundir@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/sctp/ipv6.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -209,6 +209,7 @@ static int sctp_v6_xmit(struct sk_buff *
struct sock *sk = skb->sk;
struct ipv6_pinfo *np = inet6_sk(sk);
struct flowi6 *fl6 = &transport->fl.u.ip6;
+ int res;
pr_debug("%s: skb:%p, len:%d, src:%pI6 dst:%pI6\n", __func__, skb,
skb->len, &fl6->saddr, &fl6->daddr);
@@ -220,7 +221,10 @@ static int sctp_v6_xmit(struct sk_buff *
SCTP_INC_STATS(sock_net(sk), SCTP_MIB_OUTSCTPPACKS);
- return ip6_xmit(sk, skb, fl6, np->opt, np->tclass);
+ rcu_read_lock();
+ res = ip6_xmit(sk, skb, fl6, rcu_dereference(np->opt), np->tclass);
+ rcu_read_unlock();
+ return res;
}
/* Returns the dst cache entry for the given source and destination ip
@@ -262,7 +266,10 @@ static void sctp_v6_get_dst(struct sctp_
pr_debug("src=%pI6 - ", &fl6->saddr);
}
- final_p = fl6_update_dst(fl6, np->opt, &final);
+ rcu_read_lock();
+ final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
+ rcu_read_unlock();
+
dst = ip6_dst_lookup_flow(sk, fl6, final_p);
if (!asoc || saddr)
goto out;
@@ -321,7 +328,7 @@ static void sctp_v6_get_dst(struct sctp_
if (baddr) {
fl6->saddr = baddr->v6.sin6_addr;
fl6->fl6_sport = baddr->v6.sin6_port;
- final_p = fl6_update_dst(fl6, np->opt, &final);
+ final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
dst = ip6_dst_lookup_flow(sk, fl6, final_p);
}