Return-path: Received: from mail.candelatech.com ([208.74.158.172]:38404 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751239AbaDQAlD (ORCPT ); Wed, 16 Apr 2014 20:41:03 -0400 From: greearb@candelatech.com To: ath9k-devel@venema.h4ckr.net Cc: linux-wireless@vger.kernel.org, Ben Greear Subject: [PATCH] ath9k: Prevent divide by zero kernel crash. Date: Wed, 16 Apr 2014 17:40:40 -0700 Message-Id: <1397695240-13710-1-git-send-email-greearb@candelatech.com> (sfid-20140417_024139_123476_132880EB) Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Ben Greear Make sure we cannot ever assign beacon interval to zero. Signed-off-by: Ben Greear --- drivers/net/wireless/ath/ath9k/beacon.c | 4 ++++ drivers/net/wireless/ath/ath9k/recv.c | 3 ++- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c index 2e8bba0..5391f01 100644 --- a/drivers/net/wireless/ath/ath9k/beacon.c +++ b/drivers/net/wireless/ath/ath9k/beacon.c @@ -443,6 +443,8 @@ static u32 ath9k_mod_tsf64_tu(u64 tsf, u32 div_tu) { u32 tsf_mod, tsf_hi, tsf_lo, mod_hi, mod_lo; + if (WARN_ON_ONCE(div_tu == 0)) + div_tu = 100; tsf_mod = tsf & (BIT(10) - 1); tsf_hi = tsf >> 32; tsf_lo = ((u32) tsf) >> 10; @@ -667,6 +669,8 @@ static void ath9k_cache_beacon_config(struct ath_softc *sc, "Caching beacon data for BSS: %pM\n", bss_conf->bssid); cur_conf->beacon_interval = bss_conf->beacon_int; + if (WARN_ON_ONCE(cur_conf->beacon_interval == 0)) + cur_conf->beacon_interval = 100; cur_conf->dtim_period = bss_conf->dtim_period; cur_conf->listen_interval = 1; cur_conf->dtim_count = 1; diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c index b97217d..79c20c7 100644 --- a/drivers/net/wireless/ath/ath9k/recv.c +++ b/drivers/net/wireless/ath/ath9k/recv.c @@ -538,7 +538,8 @@ static void ath_rx_ps_beacon(struct ath_softc *sc, struct sk_buff *skb) sc->ps_flags &= ~PS_BEACON_SYNC; ath_dbg(common, PS, "Reconfigure beacon timers based on synchronized timestamp\n"); - ath9k_set_beacon(sc); + if (!(WARN_ON_ONCE(sc->cur_beacon_conf.beacon_interval == 0))) + ath9k_set_beacon(sc); } if (ath_beacon_dtim_pending_cab(skb)) { -- 1.7.11.7