tcp/dccp: fix ireq->opt races

[mirror_ubuntu-artful-kernel.git] / net / ipv4 / cipso_ipv4.c

diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 2ae8f54cb32148f2499f78ecbf29259db36bd207..82178cc69c9618bae69c096290a7a96a8b8bade0 100644 (file)
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -1951,7 +1951,7 @@ int cipso_v4_req_setattr(struct request_sock *req,
        buf = NULL;
 
        req_inet = inet_rsk(req);
-       opt = xchg(&req_inet->opt, opt);
+       opt = xchg((__force struct ip_options_rcu **)&req_inet->ireq_opt, opt);
        if (opt)
                kfree_rcu(opt, rcu);
 
@@ -1973,11 +1973,13 @@ req_setattr_failure:
  * values on failure.
  *
  */
-static int cipso_v4_delopt(struct ip_options_rcu **opt_ptr)
+static int cipso_v4_delopt(struct ip_options_rcu __rcu **opt_ptr)
 {
+       struct ip_options_rcu *opt = rcu_dereference_protected(*opt_ptr, 1);
        int hdr_delta = 0;
-       struct ip_options_rcu *opt = *opt_ptr;
 
+       if (!opt || opt->opt.cipso == 0)
+               return 0;
        if (opt->opt.srr || opt->opt.rr || opt->opt.ts || opt->opt.router_alert) {
                u8 cipso_len;
                u8 cipso_off;
@@ -2039,14 +2041,10 @@ static int cipso_v4_delopt(struct ip_options_rcu **opt_ptr)
  */
 void cipso_v4_sock_delattr(struct sock *sk)
 {
-       int hdr_delta;
-       struct ip_options_rcu *opt;
        struct inet_sock *sk_inet;
+       int hdr_delta;
 
        sk_inet = inet_sk(sk);
-       opt = rcu_dereference_protected(sk_inet->inet_opt, 1);
-       if (!opt || opt->opt.cipso == 0)
-               return;
 
        hdr_delta = cipso_v4_delopt(&sk_inet->inet_opt);
        if (sk_inet->is_icsk && hdr_delta > 0) {
@@ -2066,15 +2064,7 @@ void cipso_v4_sock_delattr(struct sock *sk)
  */
 void cipso_v4_req_delattr(struct request_sock *req)
 {
-       struct ip_options_rcu *opt;
-       struct inet_request_sock *req_inet;
-
-       req_inet = inet_rsk(req);
-       opt = req_inet->opt;
-       if (!opt || opt->opt.cipso == 0)
-               return;
-
-       cipso_v4_delopt(&req_inet->opt);
+       cipso_v4_delopt(&inet_rsk(req)->ireq_opt);
 }
 
 /**