From 97b09648744e883f996f8ffb9b8c48315cbc1b9f Mon Sep 17 00:00:00 2001 From: Vladis Dronov Date: Wed, 13 Sep 2017 00:21:21 +0200 Subject: [PATCH] nl80211: check for the required netlink attributes presence commit e785fa0a164aa11001cba931367c7f94ffaff888 upstream. nl80211_set_rekey_data() does not check if the required attributes NL80211_REKEY_DATA_{REPLAY_CTR,KEK,KCK} are present when processing NL80211_CMD_SET_REKEY_OFFLOAD request. This request can be issued by users with CAP_NET_ADMIN privilege and may result in NULL dereference and a system crash. Add a check for the required attributes presence. This patch is based on the patch by bo Zhang. This fixes CVE-2017-12153. Change-Id: Ia6ce5dd03a88412020e47a681cb75f4e8c1aafd8 References: https://bugzilla.redhat.com/show_bug.cgi?id=1491046 Fixes: e5497d766ad ("cfg80211/nl80211: support GTK rekey offload") Reported-by: bo Zhang Signed-off-by: Vladis Dronov Signed-off-by: Johannes Berg Signed-off-by: Ben Hutchings --- net/wireless/nl80211.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 92ed089b0856..4025dd84c158 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -8305,6 +8305,9 @@ static int nl80211_set_rekey_data(struct sk_buff *skb, struct genl_info *info) if (err) return err; + if (!tb[NL80211_REKEY_DATA_REPLAY_CTR] || !tb[NL80211_REKEY_DATA_KEK] || + !tb[NL80211_REKEY_DATA_KCK]) + return -EINVAL; if (nla_len(tb[NL80211_REKEY_DATA_REPLAY_CTR]) != NL80211_REPLAY_CTR_LEN) return -ERANGE; if (nla_len(tb[NL80211_REKEY_DATA_KEK]) != NL80211_KEK_LEN)