When IEEE80211_HW_SIGNAL_UNSPEC is set, mac80211 will perform a division by max_signal in ieee80211_bss_info_update. If max_signal is not properly set by the driver (for example it is zero) this leads to a divide error and crash. Thanks to Larry Finger, who pointed me to this. This patch adds in ieee80211_register_hw one more check to detect this condition and eventually returns -EINVAL, as already done for other checks already performed there. Signed-off-by: andrea merello <andrea.merello@xxxxxxxxx> --- net/mac80211/main.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/mac80211/main.c b/net/mac80211/main.c index d767cfb..913307a 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -758,6 +758,9 @@ int ieee80211_register_hw(struct ieee80211_hw *hw) local->hw.offchannel_tx_hw_queue >= local->hw.queues)) return -EINVAL; + if (hw->flags & IEEE80211_HW_SIGNAL_UNSPEC && hw->max_signal <= 0) + return -EINVAL; + #ifdef CONFIG_PM if (hw->wiphy->wowlan && (!local->ops->suspend || !local->ops->resume)) return -EINVAL; -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
