[PATCH AUTOSEL 4.4 06/18] cfg80211: nl80211_update_ft_ies() to validate NL80211_ATTR_IE

From: Sasha Levin
Date: Mon Sep 24 2018 - 10:51:31 EST

From: Arunk Khandavalli <akhandav@xxxxxxxxxxxxxx>

[ Upstream commit 4f0223bfe9c3e62d8f45a85f1ef1b18a8a263ef9 ]

nl80211_update_ft_ies() tried to validate NL80211_ATTR_IE with
is_valid_ie_attr() before dereferencing it, but that helper function
returns true in case of NULL pointer (i.e., attribute not included).
This can result to dereferencing a NULL pointer. Fix that by explicitly
checking that NL80211_ATTR_IE is included.

Fixes: 355199e02b83 ("cfg80211: Extend support for IEEE 802.11r Fast BSS Transition")
Signed-off-by: Arunk Khandavalli <akhandav@xxxxxxxxxxxxxx>
Signed-off-by: Jouni Malinen <jouni@xxxxxxxxxxxxxx>
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
net/wireless/nl80211.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index b07fd8b8b50c..642a78079ae1 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -10014,6 +10014,7 @@ static int nl80211_update_ft_ies(struct sk_buff *skb, struct genl_info *info)

if (!info->attrs[NL80211_ATTR_MDID] ||
+ !info->attrs[NL80211_ATTR_IE] ||
return -EINVAL;