From: Johannes Berg Date: Fri, 11 Oct 2013 13:47:06 +0000 (+0200) Subject: mac80211: fix crash if bitrate calculation goes wrong X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d86aa4f8ca58898ec6a94c0635da20b948171ed7;p=linux-beck.git mac80211: fix crash if bitrate calculation goes wrong If a frame's timestamp is calculated, and the bitrate calculation goes wrong and returns zero, the system will attempt to divide by zero and crash. Catch this case and print the rate information that the driver reported when this happens. Cc: stable@vger.kernel.org Reported-by: Thomas Lindroth Signed-off-by: Johannes Berg --- diff --git a/net/mac80211/util.c b/net/mac80211/util.c index 9c3200bcfc02..69e4ef5348a0 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -2238,6 +2238,10 @@ u64 ieee80211_calculate_rx_timestamp(struct ieee80211_local *local, } rate = cfg80211_calculate_bitrate(&ri); + if (WARN_ONCE(!rate, + "Invalid bitrate: flags=0x%x, idx=%d, vht_nss=%d\n", + status->flag, status->rate_idx, status->vht_nss)) + return 0; /* rewind from end of MPDU */ if (status->flag & RX_FLAG_MACTIME_END)