From e223e42aac30bf81f9302c676cdf58cf2bf36950 Mon Sep 17 00:00:00 2001 From: Gregory Greenman Date: Fri, 22 Jan 2021 14:52:37 +0200 Subject: [PATCH] iwlwifi: mvm: invalidate IDs of internal stations at mvm start Having sta_id not set for aux_sta and snif_sta can potentially lead to a hard to debug issue in case remove station is called without an add. In this case sta_id 0, an unrelated regular station, will be removed. In fact, we do have a FW assert that occures rarely and from the debug data analysis it looks like sta_id 0 is removed by mistake, though it's hard to pinpoint the exact flow. The WARN_ON in this patch should help to find it. Signed-off-by: Gregory Greenman Signed-off-by: Luca Coelho Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/iwlwifi.20210122144849.5dc6dd9b22d5.I2add1b5ad24d0d0a221de79d439c09f88fcaf15d@changeid --- drivers/net/wireless/intel/iwlwifi/mvm/ops.c | 4 ++++ drivers/net/wireless/intel/iwlwifi/mvm/sta.c | 6 ++++++ 2 files changed, 10 insertions(+) diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c index 98f62d78cf9c..03b41d911338 100644 --- a/drivers/net/wireless/intel/iwlwifi/mvm/ops.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/ops.c @@ -791,6 +791,10 @@ iwl_op_mode_mvm_start(struct iwl_trans *trans, const struct iwl_cfg *cfg, if (!mvm->scan_cmd) goto out_free; + /* invalidate ids to prevent accidental removal of sta_id 0 */ + mvm->aux_sta.sta_id = IWL_MVM_INVALID_STA; + mvm->snif_sta.sta_id = IWL_MVM_INVALID_STA; + /* Set EBS as successful as long as not stated otherwise by the FW. */ mvm->last_ebs_successful = true; diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c index dc174410bf9c..578c353ae02c 100644 --- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c @@ -2057,6 +2057,9 @@ int iwl_mvm_rm_snif_sta(struct iwl_mvm *mvm, struct ieee80211_vif *vif) lockdep_assert_held(&mvm->mutex); + if (WARN_ON_ONCE(mvm->snif_sta.sta_id == IWL_MVM_INVALID_STA)) + return -EINVAL; + iwl_mvm_disable_txq(mvm, NULL, mvm->snif_queue, IWL_MAX_TID_COUNT, 0); ret = iwl_mvm_rm_sta_common(mvm, mvm->snif_sta.sta_id); if (ret) @@ -2071,6 +2074,9 @@ int iwl_mvm_rm_aux_sta(struct iwl_mvm *mvm) lockdep_assert_held(&mvm->mutex); + if (WARN_ON_ONCE(mvm->aux_sta.sta_id == IWL_MVM_INVALID_STA)) + return -EINVAL; + iwl_mvm_disable_txq(mvm, NULL, mvm->aux_queue, IWL_MAX_TID_COUNT, 0); ret = iwl_mvm_rm_sta_common(mvm, mvm->aux_sta.sta_id); if (ret) -- 2.20.1