4.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Srinivas Dasari <dasaris@xxxxxxxxxxxxxxxx> commit 0a27844ce86d039d74221dd56cd8c0349b146b63 upstream. nla policy checks for only maximum length of the attribute data when the attribute type is NLA_BINARY. If userspace sends less data than specified, cfg80211 may access illegal memory. When type is NLA_UNSPEC, nla policy check ensures that userspace sends minimum specified length number of bytes. Remove type assignment to NLA_BINARY from nla_policy of NL80211_NAN_FUNC_SERVICE_ID to make these NLA_UNSPEC and to make sure minimum NL80211_NAN_FUNC_SERVICE_ID_LEN bytes are received from userspace with NL80211_NAN_FUNC_SERVICE_ID. Fixes: a442b761b24 ("cfg80211: add add_nan_func / del_nan_func") Signed-off-by: Srinivas Dasari <dasaris@xxxxxxxxxxxxxxxx> Signed-off-by: Jouni Malinen <jouni@xxxxxxxxxxxxxxxx> Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/wireless/nl80211.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -520,7 +520,7 @@ nl80211_bss_select_policy[NL80211_BSS_SE static const struct nla_policy nl80211_nan_func_policy[NL80211_NAN_FUNC_ATTR_MAX + 1] = { [NL80211_NAN_FUNC_TYPE] = { .type = NLA_U8 }, - [NL80211_NAN_FUNC_SERVICE_ID] = { .type = NLA_BINARY, + [NL80211_NAN_FUNC_SERVICE_ID] = { .len = NL80211_NAN_FUNC_SERVICE_ID_LEN }, [NL80211_NAN_FUNC_PUBLISH_TYPE] = { .type = NLA_U8 }, [NL80211_NAN_FUNC_PUBLISH_BCAST] = { .type = NLA_FLAG },