From: Srinivas Dasari Date: Thu, 6 Jul 2017 22:43:42 +0000 (+0300) Subject: cfg80211: Validate frequencies nested in NL80211_ATTR_SCAN_FREQUENCIES X-Git-Tag: v4.11.12~49 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=880b98c33913e23c6f97e5f838b235faa9d54abb;p=thirdparty%2Fkernel%2Fstable.git cfg80211: Validate frequencies nested in NL80211_ATTR_SCAN_FREQUENCIES commit d7f13f7450369281a5d0ea463cc69890a15923ae upstream. 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)") Signed-off-by: Srinivas Dasari Signed-off-by: Jouni Malinen Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 13050bf8fbf3e..f6d2ca413ab01 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -6422,6 +6422,10 @@ 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++; /*