Return-path: Received: from alexa-out.qualcomm.com ([129.46.98.28]:2467 "EHLO alexa-out-lv-02.qualcomm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751619AbdGFWph (ORCPT ); Thu, 6 Jul 2017 18:45:37 -0400 From: Jouni Malinen To: Johannes Berg CC: , Srinivas Dasari , Jouni Malinen Subject: [PATCH 4/4] cfg80211: Validate frequencies nested in NL80211_ATTR_SCAN_FREQUENCIES Date: Fri, 7 Jul 2017 01:43:42 +0300 Message-ID: <1499381022-5389-4-git-send-email-jouni@qca.qualcomm.com> (sfid-20170707_004539_903339_684FD612) In-Reply-To: <1499381022-5389-1-git-send-email-jouni@qca.qualcomm.com> References: <1499381022-5389-1-git-send-email-jouni@qca.qualcomm.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Srinivas Dasari validate_scan_freqs() retrieves frequencies from attributes nested in the attribute NL80211_ATTR_SCAN_FREQUENCIES with nla_get_u32(), which reads 4 bytes from each attribute without validating the size of data received. Attributes nested in NL80211_ATTR_SCAN_FREQUENCIES don't have an nla policy. Validate size of each attribute before parsing to avoid potential buffer overread. Fixes: 2a519311926 ("cfg80211/nl80211: scanning (and mac80211 update to use it)") Cc: stable@vger.kernel.org Signed-off-by: Srinivas Dasari Signed-off-by: Jouni Malinen --- net/wireless/nl80211.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 0a63b95..740d3c1 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -6469,6 +6469,9 @@ static int validate_scan_freqs(struct nlattr *freqs) struct nlattr *attr1, *attr2; int n_channels = 0, tmp1, tmp2; + nla_for_each_nested(attr1, freqs, tmp1) + if (nla_len(attr1) != sizeof(u32)) + return 0; nla_for_each_nested(attr1, freqs, tmp1) { n_channels++; /* -- 2.7.4