From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Fri, 4 Jan 2013 00:34:22 +0000 (+0000)
Subject: rtnetlink: fix rtnl_calcit() and rtnl_dump_ifinfo()
X-Git-Tag: firefly_0821_release~7541^2~127
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=b18401af7f51cddd5d2e03c9b800ba7dd60f18a0;p=firefly-linux-kernel-4.4.55.git

rtnetlink: fix rtnl_calcit() and rtnl_dump_ifinfo()

commit a4b64fbe482c7766f7925f03067fc637716bfa3f upstream.

nlmsg_parse() might return an error, so test its return value before
potential random memory accesses.

Errors introduced in commit 115c9b81928 (rtnetlink: Fix problem with
buffer allocation)

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index e41ce2a0264a..49f281e60643 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1044,11 +1044,12 @@ static int rtnl_dump_ifinfo(struct sk_buff *skb, struct netlink_callback *cb)
 
 	rcu_read_lock();
 
-	nlmsg_parse(cb->nlh, sizeof(struct rtgenmsg), tb, IFLA_MAX,
-		    ifla_policy);
+	if (nlmsg_parse(cb->nlh, sizeof(struct rtgenmsg), tb, IFLA_MAX,
+			ifla_policy) >= 0) {
 
-	if (tb[IFLA_EXT_MASK])
-		ext_filter_mask = nla_get_u32(tb[IFLA_EXT_MASK]);
+		if (tb[IFLA_EXT_MASK])
+			ext_filter_mask = nla_get_u32(tb[IFLA_EXT_MASK]);
+	}
 
 	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
 		idx = 0;
@@ -1874,10 +1875,11 @@ static u16 rtnl_calcit(struct sk_buff *skb, struct nlmsghdr *nlh)
 	u32 ext_filter_mask = 0;
 	u16 min_ifinfo_dump_size = 0;
 
-	nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, IFLA_MAX, ifla_policy);
-
-	if (tb[IFLA_EXT_MASK])
-		ext_filter_mask = nla_get_u32(tb[IFLA_EXT_MASK]);
+	if (nlmsg_parse(nlh, sizeof(struct rtgenmsg), tb, IFLA_MAX,
+			ifla_policy) >= 0) {
+		if (tb[IFLA_EXT_MASK])
+			ext_filter_mask = nla_get_u32(tb[IFLA_EXT_MASK]);
+	}
 
 	if (!ext_filter_mask)
 		return NLMSG_GOODSIZE;