From ad788b5e079484aa1d48aa90a3ebd7d954d2e7db Mon Sep 17 00:00:00 2001 From: "John W. Linville" Date: Wed, 1 Oct 2008 15:45:02 -0400 Subject: [PATCH] mac80211: avoid "Wireless Event too big" message for assoc response The association response IEs are sent to userland with an IWEVCUSTOM event, which unfortunately is limited to a little more than 100 bytes of IE information with the encoding used. Many APs send so much IE information that this message overflows. When the IWEVCUSTOM event is too large, the kernel doesn't send it to userland anyway -- better just not to send it. An attempt was made by Jouni Malinen to correct this issue by converting to use IWEVASSOCREQIE and IWEVASSOCRESPIE messages instead ("mac80211: Use IWEVASSOCREQIE instead of IWEVCUSTOM"). Unfortunately, that caused a problem due to 32-/64-bit interactions on some systems and was reverted after the 'userland ABI' rule was invoked. That leaves us with this option instead of a proper fix, at least until we move to a cfg80211-based solution. Signed-off-by: John W. Linville --- net/mac80211/mlme.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index edc339d649c4..49f86fa56bff 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -690,9 +690,11 @@ static void ieee80211_sta_send_associnfo(struct ieee80211_sub_if_data *sdata, } } - memset(&wrqu, 0, sizeof(wrqu)); - wrqu.data.length = len; - wireless_send_event(dev, IWEVCUSTOM, &wrqu, buf); + if (len <= IW_CUSTOM_MAX) { + memset(&wrqu, 0, sizeof(wrqu)); + wrqu.data.length = len; + wireless_send_event(sdata->dev, IWEVCUSTOM, &wrqu, buf); + } kfree(buf); } -- 2.20.1