From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from aserp1040.oracle.com ([141.146.126.69]:28738 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751065AbbKZMDZ (ORCPT ); Thu, 26 Nov 2015 07:03:25 -0500 Date: Thu, 26 Nov 2015 15:03:17 +0300 From: Dan Carpenter To: johannes.berg@intel.com Cc: linux-wireless@vger.kernel.org Subject: (bug report) iwlwifi: inconsitent NULL checking Message-ID: <20151126120317.GJ10556@mwanda> (sfid-20151126_130328_960203_265EA1F6) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-wireless-owner@vger.kernel.org List-ID: [ All old wireless warnings are showing up as new because the files moved around in linux-next. - dan ] Hello Johannes Berg, The patch 8ca151b568b6: "iwlwifi: add the MVM driver" from Jan 24, 2013, leads to the following static checker warning: drivers/net/wireless/intel/iwlwifi/mvm/rs.c:2802 rs_get_rate() error: we previously assumed 'lq_sta' could be null (see line 2793) drivers/net/wireless/intel/iwlwifi/mvm/rs.c 2790 /* TODO: handle rate_idx_mask and rate_idx_mcs_mask */ 2791 2792 /* Treat uninitialized rate scaling data same as non-existing. */ 2793 if (lq_sta && !lq_sta->pers.drv) { ^^^^^^ Check. 2794 IWL_DEBUG_RATE(mvm, "Rate scaling not initialized yet.\n"); 2795 mvm_sta = NULL; 2796 } 2797 2798 /* Send management frames and NO_ACK data using lowest rate. */ 2799 if (rate_control_send_low(sta, mvm_sta, txrc)) 2800 return; 2801 2802 iwl_mvm_hwrate_to_tx_rate(lq_sta->last_rate_n_flags, ^^^^^^^^^^^^^^^^^^^^^^^^^ Uchecked dereference. 2803 info->band, &info->control.rates[0]); 2804 info->control.rates[0].count = 1; 2805 See also: drivers/net/wireless/intel/iwlwifi/dvm/rs.c:2742 rs_get_rate() error: we previously assumed 'lq_sta' could be null (see line 2733) regards, dan carpenter