From patchwork Mon Nov 7 08:10:21 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yoshihiro Shimoda X-Patchwork-Id: 13034010 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D621AC433FE for ; Mon, 7 Nov 2022 08:10:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231567AbiKGIKe (ORCPT ); Mon, 7 Nov 2022 03:10:34 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59146 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231351AbiKGIKd (ORCPT ); Mon, 7 Nov 2022 03:10:33 -0500 Received: from relmlie6.idc.renesas.com (relmlor2.renesas.com [210.160.252.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id A739013F61; Mon, 7 Nov 2022 00:10:30 -0800 (PST) X-IronPort-AV: E=Sophos;i="5.96,143,1665414000"; d="scan'208";a="141750250" Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie6.idc.renesas.com with ESMTP; 07 Nov 2022 17:10:29 +0900 Received: from localhost.localdomain (unknown [10.166.15.32]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id E05C94002C03; Mon, 7 Nov 2022 17:10:29 +0900 (JST) From: Yoshihiro Shimoda To: davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com Cc: netdev@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Yoshihiro Shimoda , coverity-bot Subject: [PATCH] net: ethernet: renesas: rswitch: Fix endless loop in error paths Date: Mon, 7 Nov 2022 17:10:21 +0900 Message-Id: <20221107081021.2955122-1-yoshihiro.shimoda.uh@renesas.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org Coverity reported that the error path in rswitch_gwca_queue_alloc_skb() has an issue to cause endless loop. So, fix the issue by changing variables' types from u32 to int. After changed the types, rswitch_tx_free() should use rswitch_get_num_cur_queues() to calculate number of current queues. Reported-by: coverity-bot Addresses-Coverity-ID: 1527147 ("Control flow issues") Fixes: 3590918b5d07 ("net: ethernet: renesas: Add support for "Ethernet Switch"") Signed-off-by: Yoshihiro Shimoda --- drivers/net/ethernet/renesas/rswitch.c | 17 +++++++++-------- drivers/net/ethernet/renesas/rswitch.h | 6 +++--- 2 files changed, 12 insertions(+), 11 deletions(-) diff --git a/drivers/net/ethernet/renesas/rswitch.c b/drivers/net/ethernet/renesas/rswitch.c index f0168fedfef9..3bd5e6239855 100644 --- a/drivers/net/ethernet/renesas/rswitch.c +++ b/drivers/net/ethernet/renesas/rswitch.c @@ -219,9 +219,9 @@ static void rswitch_ack_data_irq(struct rswitch_private *priv, int index) iowrite32(BIT(index % 32), priv->addr + offs); } -static u32 rswitch_next_queue_index(struct rswitch_gwca_queue *gq, bool cur, u32 num) +static int rswitch_next_queue_index(struct rswitch_gwca_queue *gq, bool cur, int num) { - u32 index = cur ? gq->cur : gq->dirty; + int index = cur ? gq->cur : gq->dirty; if (index + num >= gq->ring_size) index = (index + num) % gq->ring_size; @@ -231,7 +231,7 @@ static u32 rswitch_next_queue_index(struct rswitch_gwca_queue *gq, bool cur, u32 return index; } -static u32 rswitch_get_num_cur_queues(struct rswitch_gwca_queue *gq) +static int rswitch_get_num_cur_queues(struct rswitch_gwca_queue *gq) { if (gq->cur >= gq->dirty) return gq->cur - gq->dirty; @@ -250,9 +250,9 @@ static bool rswitch_is_queue_rxed(struct rswitch_gwca_queue *gq) } static int rswitch_gwca_queue_alloc_skb(struct rswitch_gwca_queue *gq, - u32 start_index, u32 num) + int start_index, int num) { - u32 i, index; + int i, index; for (i = 0; i < num; i++) { index = (i + start_index) % gq->ring_size; @@ -410,12 +410,12 @@ static int rswitch_gwca_queue_format(struct net_device *ndev, static int rswitch_gwca_queue_ts_fill(struct net_device *ndev, struct rswitch_gwca_queue *gq, - u32 start_index, u32 num) + int start_index, int num) { struct rswitch_device *rdev = netdev_priv(ndev); struct rswitch_ext_ts_desc *desc; dma_addr_t dma_addr; - u32 i, index; + int i, index; for (i = 0; i < num; i++) { index = (i + start_index) % gq->ring_size; @@ -736,7 +736,8 @@ static int rswitch_tx_free(struct net_device *ndev, bool free_txed_only) int free_num = 0; int size; - for (; gq->cur - gq->dirty > 0; gq->dirty = rswitch_next_queue_index(gq, false, 1)) { + for (; rswitch_get_num_cur_queues(gq) > 0; + gq->dirty = rswitch_next_queue_index(gq, false, 1)) { desc = &gq->ring[gq->dirty]; if (free_txed_only && (desc->desc.die_dt & DT_MASK) != DT_FEMPTY) break; diff --git a/drivers/net/ethernet/renesas/rswitch.h b/drivers/net/ethernet/renesas/rswitch.h index 778177ec8d4f..edbdd1b98d3d 100644 --- a/drivers/net/ethernet/renesas/rswitch.h +++ b/drivers/net/ethernet/renesas/rswitch.h @@ -908,9 +908,9 @@ struct rswitch_gwca_queue { struct rswitch_ext_ts_desc *ts_ring; }; dma_addr_t ring_dma; - u32 ring_size; - u32 cur; - u32 dirty; + int ring_size; + int cur; + int dirty; struct sk_buff **skbs; struct net_device *ndev; /* queue to ndev for irq */