On Fri, Oct 04, 2019 at 10:51:31AM +0100, Will Deacon wrote:
Although this shouldn't occur in practice, it's a good idea to bounds check the length field of the SSID element prior to using it for things like allocations or memcpy operations.
Cc: stable@vger.kernel.org Cc: Johannes Berg johannes@sipsolutions.net Cc: Kees Cook keescook@chromium.org Reported-by: Nicolas Waisman nico@semmle.com Signed-off-by: Will Deacon will@kernel.org
Reviewed-by: Kees Cook keescook@chromium.org
-Kees
net/mac80211/mlme.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index 26a2f49208b6..54dd8849d1cc 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -2633,7 +2633,8 @@ struct sk_buff *ieee80211_ap_probereq_get(struct ieee80211_hw *hw, rcu_read_lock(); ssid = ieee80211_bss_get_ie(cbss, WLAN_EID_SSID);
- if (WARN_ON_ONCE(ssid == NULL))
- if (WARN_ONCE(!ssid || ssid[1] > IEEE80211_MAX_SSID_LEN,
"invalid SSID element (len=%d)", ssid ? ssid[1] : -1))@@ -5233,7 +5234,7 @@ int ieee80211_mgd_assoc(struct ieee80211_sub_if_data *sdata, rcu_read_lock(); ssidie = ieee80211_bss_get_ie(req->bss, WLAN_EID_SSID);
- if (!ssidie) {
- if (!ssidie || ssidie[1] > sizeof(assoc_data->ssid)) { rcu_read_unlock(); kfree(assoc_data); return -EINVAL;
-- 2.23.0.581.g78d2f28ef7-goog