From: Suren Baghdasaryan <surenb@google.com>
Date: Tue, 15 Aug 2017 22:12:24 +0000 (-0700)
Subject: ANDROID: net: xfrm: check dir value of xfrm_userpolicy_id
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=33f17703cceb1258958fb2049fc0b18b6cc8dea6;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

ANDROID: net: xfrm: check dir value of xfrm_userpolicy_id

Check user provided dir value to prevent out-of-bound access
which may occur if dir is not less than XFRM_POLICY_MAX.

(url: http://seclists.org/bugtraq/2017/Jul/30)

Bug: 64257838
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Change-Id: I5bbdf95e14a61bdf5207977d9a5a4465bc848da0
---

diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index e44a0fed48dd..1429960cba21 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -1734,6 +1734,10 @@ static struct sk_buff *xfrm_policy_netlink(struct sk_buff *in_skb,
 	struct sk_buff *skb;
 	int err;
 
+	err = verify_policy_dir(dir);
+	if (err)
+		return ERR_PTR(err);
+
 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
 	if (!skb)
 		return ERR_PTR(-ENOMEM);
@@ -2255,6 +2259,10 @@ static int xfrm_do_migrate(struct sk_buff *skb, struct nlmsghdr *nlh,
 	struct net *net = sock_net(skb->sk);
 	struct xfrm_encap_tmpl  *encap = NULL;
 
+	err = verify_policy_dir(pi->dir);
+	if (err)
+		return err;
+
 	if (attrs[XFRMA_MIGRATE] == NULL)
 		return -EINVAL;
 
@@ -2388,6 +2396,11 @@ static int xfrm_send_migrate(const struct xfrm_selector *sel, u8 dir, u8 type,
 {
 	struct net *net = &init_net;
 	struct sk_buff *skb;
+	int err;
+
+	err = verify_policy_dir(dir);
+	if (err)
+		return err;
 
 	skb = nlmsg_new(xfrm_migrate_msgsize(num_migrate, !!k, !!encap),
 			GFP_ATOMIC);
@@ -3057,6 +3070,11 @@ out_free_skb:
 
 static int xfrm_send_policy_notify(struct xfrm_policy *xp, int dir, const struct km_event *c)
 {
+	int err;
+
+	err = verify_policy_dir(dir);
+	if (err)
+		return err;
 
 	switch (c->event) {
 	case XFRM_MSG_NEWPOLICY: