From patchwork Fri Jan 15 11:05:53 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Coelho X-Patchwork-Id: 12022273 X-Patchwork-Delegate: kvalo@adurom.com Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1E605C433E9 for ; Fri, 15 Jan 2021 11:06:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EE56B223C8 for ; Fri, 15 Jan 2021 11:06:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726993AbhAOLG4 (ORCPT ); Fri, 15 Jan 2021 06:06:56 -0500 Received: from paleale.coelho.fi ([176.9.41.70]:40322 "EHLO farmhouse.coelho.fi" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726278AbhAOLGz (ORCPT ); Fri, 15 Jan 2021 06:06:55 -0500 Received: from 91-156-6-193.elisa-laajakaista.fi ([91.156.6.193] helo=redipa.ger.corp.intel.com) by farmhouse.coelho.fi with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1l0Mvg-003hBK-IX; Fri, 15 Jan 2021 13:06:08 +0200 From: Luca Coelho To: kvalo@codeaurora.org Cc: linux-wireless@vger.kernel.org Date: Fri, 15 Jan 2021 13:05:53 +0200 Message-Id: X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210115110558.1248847-1-luca@coelho.fi> References: <20210115110558.1248847-1-luca@coelho.fi> MIME-Version: 1.0 Subject: [PATCH for v5.11 07/12] iwlwifi: queue: don't crash if txq->entries is NULL Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org From: Emmanuel Grumbach The code was really awkward, we would first dereference txq->entries when calling iwl_txq_genX_tfd_unmap and then we would check that txq->entries is non-NULL. Fix that by exiting if txq->entries is NULL. Signed-off-by: Emmanuel Grumbach Signed-off-by: Luca Coelho --- drivers/net/wireless/intel/iwlwifi/queue/tx.c | 49 +++++++++---------- 1 file changed, 24 insertions(+), 25 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/queue/tx.c b/drivers/net/wireless/intel/iwlwifi/queue/tx.c index 27eea909e32d..62c0c4cbe481 100644 --- a/drivers/net/wireless/intel/iwlwifi/queue/tx.c +++ b/drivers/net/wireless/intel/iwlwifi/queue/tx.c @@ -142,26 +142,25 @@ void iwl_txq_gen2_free_tfd(struct iwl_trans *trans, struct iwl_txq *txq) * idx is bounded by n_window */ int idx = iwl_txq_get_cmd_index(txq, txq->read_ptr); + struct sk_buff *skb; lockdep_assert_held(&txq->lock); + if (!txq->entries) + return; + iwl_txq_gen2_tfd_unmap(trans, &txq->entries[idx].meta, iwl_txq_get_tfd(trans, txq, idx)); - /* free SKB */ - if (txq->entries) { - struct sk_buff *skb; - - skb = txq->entries[idx].skb; + skb = txq->entries[idx].skb; - /* Can be called from irqs-disabled context - * If skb is not NULL, it means that the whole queue is being - * freed and that the queue is not empty - free the skb - */ - if (skb) { - iwl_op_mode_free_skb(trans->op_mode, skb); - txq->entries[idx].skb = NULL; - } + /* Can be called from irqs-disabled context + * If skb is not NULL, it means that the whole queue is being + * freed and that the queue is not empty - free the skb + */ + if (skb) { + iwl_op_mode_free_skb(trans->op_mode, skb); + txq->entries[idx].skb = NULL; } } @@ -1494,28 +1493,28 @@ void iwl_txq_free_tfd(struct iwl_trans *trans, struct iwl_txq *txq) */ int rd_ptr = txq->read_ptr; int idx = iwl_txq_get_cmd_index(txq, rd_ptr); + struct sk_buff *skb; lockdep_assert_held(&txq->lock); + if (!txq->entries) + return; + /* We have only q->n_window txq->entries, but we use * TFD_QUEUE_SIZE_MAX tfds */ iwl_txq_gen1_tfd_unmap(trans, &txq->entries[idx].meta, txq, rd_ptr); /* free SKB */ - if (txq->entries) { - struct sk_buff *skb; - - skb = txq->entries[idx].skb; + skb = txq->entries[idx].skb; - /* Can be called from irqs-disabled context - * If skb is not NULL, it means that the whole queue is being - * freed and that the queue is not empty - free the skb - */ - if (skb) { - iwl_op_mode_free_skb(trans->op_mode, skb); - txq->entries[idx].skb = NULL; - } + /* Can be called from irqs-disabled context + * If skb is not NULL, it means that the whole queue is being + * freed and that the queue is not empty - free the skb + */ + if (skb) { + iwl_op_mode_free_skb(trans->op_mode, skb); + txq->entries[idx].skb = NULL; } }