netdev - [PATCH net 1/2] xfrm: add rcu grace period in xfrm_policy

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Tue,  8 Dec 2015 07:22:01 -0800
From:	Eric Dumazet <edumazet@...gle.com>
To:	"David S . Miller" <davem@...emloft.net>
Cc:	netdev <netdev@...r.kernel.org>,
	Eric Dumazet <edumazet@...gle.com>,
	Steffen Klassert <steffen.klassert@...unet.com>
Subject: [PATCH net 1/2] xfrm: add rcu grace period in xfrm_policy_destroy()

We will soon switch sk->sk_policy[] to RCU protection,
as SYNACK packets are sent while listener socket is not locked.

This patch simply adds RCU grace period before struct xfrm_policy
freeing, and the corresponding rcu_head in struct xfrm_policy.

Signed-off-by: Eric Dumazet <edumazet@...gle.com>
---
 include/net/xfrm.h     |  1 +
 net/xfrm/xfrm_policy.c | 11 +++++++++--
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 4a9c21f9b4ea..8bae1ef647cd 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -548,6 +548,7 @@ struct xfrm_policy {
 	u16			family;
 	struct xfrm_sec_ctx	*security;
 	struct xfrm_tmpl       	xfrm_vec[XFRM_MAX_DEPTH];
+	struct rcu_head		rcu;
 };
 
 static inline struct net *xp_net(const struct xfrm_policy *xp)
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 18276f0cc32b..f57a5712cedd 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -303,6 +303,14 @@ struct xfrm_policy *xfrm_policy_alloc(struct net *net, gfp_t gfp)
 }
 EXPORT_SYMBOL(xfrm_policy_alloc);
 
+static void xfrm_policy_destroy_rcu(struct rcu_head *head)
+{
+	struct xfrm_policy *policy = container_of(head, struct xfrm_policy, rcu);
+
+	security_xfrm_policy_free(policy->security);
+	kfree(policy);
+}
+
 /* Destroy xfrm_policy: descendant resources must be released to this moment. */
 
 void xfrm_policy_destroy(struct xfrm_policy *policy)
@@ -312,8 +320,7 @@ void xfrm_policy_destroy(struct xfrm_policy *policy)
 	if (del_timer(&policy->timer) || del_timer(&policy->polq.hold_timer))
 		BUG();
 
-	security_xfrm_policy_free(policy->security);
-	kfree(policy);
+	call_rcu(&policy->rcu, xfrm_policy_destroy_rcu);
 }
 EXPORT_SYMBOL(xfrm_policy_destroy);
 
-- 
2.6.0.rc2.230.g3dd15c0

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html